THE INTRODUCTION AND USE OF OAT (AVENA SATIVA) CULTIVARS IN PAKISTAN

 

 

 

 

 

by

Dr. Muhammad Dost

Aga Khan Rural Support Programme (AKRSP), Gilgit, Pakistan

 

 

CONTENTS

SUMMARY

1. INTRODUCTION

2. FARMING SYSTEMS AND CROPPING PATTERNS

3. FODDER OAT INTRODUCTIONS

4. THE ROLE OF OATS

5. ROLE OF FORAGE OATS IN THE NORTHERN AREAS

6. INFORMATION ON FODDER OATS (MAINLY) FROM OTHER COUNTRIES

7. OAT RESEARCH AND INVESTIGATIONS IN PAKISTAN

8. OAT SEED PRODUCTION

9. CONCLUSIONS

10. REFERENCES

SUMMARY

This article describes how the introduction of improved, multi-cut, high yielding cultivars of forage oats (Avena sativa L.) has changed the crop’s status in Pakistan from one limited to a few stations and large farms to one of the most important cool-season fodders in the space of less than twenty years. Livestock, especially cattle and buffaloes, mainly stall-fed, are very important in Pakistan’s agricultural economy. Crop residues, sown fodder, and sometimes a little rough grazing form the basis of the ration with concentrates for commercial dairy stock.. There is a strong and increasing demand for meat and dairy products. Agricultural land is limited so the main way to increase forage availability is through increasing yield per unit area. Much of the agricultural areas have a suitable climate for year-round cropping so green feed, from a range of cold and hot season crops is the main forage supply. Urban dairying is very important and they depend on forage which is grown as a cash-crop for town sale. The introduction of the new oats coincided with a great expansion of the dairy industry which gave an added impetus to commercial forage growing in the irrigated tracts. The main winter fodder had been berseem (Trifolium alexandrinum) which is still grown on a vast scale; it is an excellent forage and yields well in autumn, if sown early and in spring but performs poorly in the coldest weeks of winter which is a major period of forage scarcity; unlike oats, berseem cannot readily be conserved as hay. Berseem is another case of astonishingly successful introduction and uptake by the farming community: it was introduced to Sind from Egypt between eighty and ninety years ago and in twenty years was the main winter forage throughout lowland Pakistan and the northern irrigated tracts of India, displacing the former winter legumes Trifolium resupinatum and Melilotus indica almost totally. The methodology of introduction, screening, selection, field testing and extension are described; along with the very necessary seed bulking and distribution. Special attention is given to the great success of fodder oats in the smallholder areas of the Northern Areas at altitudes from 1,000 m to 2,300 m, where forage is part of the subsistence system, to help over winter stocks which graze alpine pastures when they are free of snow.

World literature on fodder oat cultivation is reviewed, along with national work, in a second section and there is a comprehensive bibliography.

  1. INTRODUCTION

Resolving forage and livestock feed constraints through year round forage availability, as well as the supply of sufficient quantities of milk and milk products, have dominated Pakistan’s agricultural development strategies for almost thirty years.

A chronic fodder shortage, most serious in winter, is a major limiting factor for livestock production. There are two traditional fodder deficit periods, December-January (when the traditional winter fodder crops, especially berseem, the major winter fodder (Trifolium alexandrinum), oats (Avena sativa), shaftal (Trifolium resupinatum), and lucerne (Medicago sativa) are dormant) and May-June (when the main summer season fodder crops such as maize (Zea mays), pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor), Sorghum-Sudan grass hybrids (Sorghum vulgare var. sudanense) have just begun growth and the winter fodder season is over). Until recently seed of improved fodder cultivars, especially multicut oats have not been available, so there has been a scarcity of fodder both in terms of quantity and quality.

Oats (Avena sativa L. and Avena byzantina C. Koch) rank fifth (Dost, 1997) in terms of world production of cereals. They are also widely used as a companion crop for under-seeding of forage legumes. Oats are mainly grown in temperate and cool sub-tropical environments. In Pakistan, although not used as human food, they are an important winter fodder, in both irrigated and rain fed areas as green feed, hay, silage or grazed.

The average green yield of local cultivars (tall with very narrow leaves and thin stems, hence, not responsive to nitrogenous fertilizers due to lodging) under rain fed conditions is 20 tons/ha (Bhatti et. al., 1992), which is very low and insufficient to provide even maintenance rations for the numbers of livestock kept. In winter farmers have only dried summer grass or dry stalks of summer cereals to supplement the small amount of forage grown and have to purchase costly fodder transported in large quantities from distant, irrigated tracts.

In contrast to local landraces, improved oats grow very fast, can be cut earlier and have considerable potential to provide feed during deficit periods and low temperatures. In Balochistan province, wheat was traditionally used as fodder; however, with the introduction of improved forage oats, use of wheat for fodder has been reduced. Generally, farmers harvest these fodders at 50 percent flowering, or at a later stage to get maximum green yield with a consequent loss in quality (Dost, 1997).

The ideal fodder oat should be high in crude protein (12.42 per cent) and digestibility (in vitro dry matter digestibility - 67.42 percent), and low in crude fibre - acid detergent fibre (33.13 percent). Fodder yield and quality is greatly influenced by plant age, the crude protein content and in-vitro dry matter digestibility decreasing as the forage crop matures. Of course dry matter yield increases with advancing maturity (Dost et al., 1994).

Appreciating the importance of improved oats as a promising source of early, nutritious fodder, and to overcome the winter feed problem, the Government decided to import oat cultivars from countries thought to be the best potential sources of germplasm.

2. FARMING SYSTEMS AND CROPPING PATTERNS

In Pakistan, most of the crop production is in four major agro-ecological regions. With variations in climatic conditions, dependence on irrigation or rainfall, temperatures, soil fertility, land holding size etc., four major farming systems are prevalent:

(i) Medium to high altitude - the mountain/hilly regions such as the northern parts of North West Frontier Province (NWFP), Northern Areas and parts of Balochistan. Those near the Himalaya get reasonable rain; the Gilgit and Northern Area lands are in a rain shadow and rely on irrigation, often spate irrigation deriving from snow or glacier melt. Land holdings are very small and arable areas limited to scattered irrigable alluvial fans. Crops are often undersown in orchards. Agriculture is purely subsistence. Livestock comprise both cattle and small ruminants. Dry stock and small stock may go on transhumance. These areas are 1,000 to 2,300 m above the plains and have cold to extremely cold winters. At medium elevations, maize, rice, potato, wheat, barley, and shaftal are grown; at higher elevations (2000 m), seed potatoes, wheat, buckwheat, foxtail millet, barley, oats, and alfalfa are grown.

(ii) Medium altitude - the rain fed tracts, mainly the Pothowar plateau, Rawalpindi-Islamabad, Chakwal, Jehlum, Attok, Mianwali, D. G. Khan (Punjab), Bannu, Karak, Kohat, parts of D.I. Khan (NWFP), and most of Balochistan have conditions similar to the irrigated areas, but mainly depend on rain for cropping. Large ruminants are important, and forage production is very seasonal; there may be some rough grazing. Major crops are mustard, wheat, barley, oats, and lentils in winter; maize, sorghum, millet, guar, and groundnut in summer. Maize is an important dual purpose crop in high rainfall regions, but it is replaced by groundnut in drier areas.

(iii) The vast irrigated tracts of the plains - Central and Northern Punjab, parts of NWFP, Sindh and Balochistan are where the bulk of Pakistan’s agriculture is, with intensive commercial farming over very large areas. Large ruminants especially dairy buffaloes are important, stall-fed on crop residues and fodder. With warm temperatures and plentiful irrigation, conditions are optimal for luxuriant crop growth for ten months of the year, so year-round forage production is possible. At low altitude, in a monsoon climate, these areas are sub-tropical with searingly hot summers. Wheat, cotton, sugar cane, maize, rice, lucerne, berseem, and oats are other main crops. These areas meet almost all the grain and forage requirements of the urban dairies, including those in rain fed regions.

(iv) Coastal areas - with sub-tropical conditions, such as south Sindh and parts of Balochistan. Pearl millet, sorghum, maize, sugarcane, barley, and oats are common. The rainfall is scattered and erratic and irrigation is a factor of extreme importance, allowing cultivation in difficult areas. Amongst climatic factors, temperature and water availability are the major ones. Soils with regards to both their physical and chemical properties, which influence water holding capacity and fertility, affect production systems. These factors also influence pH and salinity levels of the soils. The major winter forages are oats (Avena sativa), berseem (Trifolium alexandrinium), lucerne (Medicago sativa), vetch (Vicia villosa var. varia), barley (Hordeum vulgare), mustard (Brassica spp.); the summer forage crops are maize (Zea mays), sorghum (Sorghum bicolor), sorghum sudan grass hybrid (Sorghum vulgare x. sudanense), pearl millet (Pennisetum glaucum), cowpeas (Vigna unguiculata), and guar (Cymopsis tetragonoloba).

In most rain fed regions, farmers grow local landraces of traditional forages such as sorghum, millet, mustard, and barley with inherent low yield potential and poor nutritive value. Livestock are fed on dried maize-sorghum-millet stalks and graze wild grass of extremely low nutritive value. In winter, wheat is cut and fed. Poor nutrition results in poor health and production. In prolonged droughts, even productive animals are sold to get cash for domestic needs. In the rain fed tracts, forage availability is the major criterion in deciding which kind of stock to keep.

Wheat and maize in rain fed areas are subsistence crops; groundnut and melons are cash crops. Sorghum with maize, and mustard intercropped in wheat, are the major green forages, supplemented by maize thinning and weeds. Barley and oats are special forages generally grown for sale near big cities and urban areas, mainly under tubewell irrigation. Several thousand tons of oat forage are transported to urban dairies daily in season. Forage fetches reasonable prices in winter for the needy farmers. Thousands of urban dairies, generally without land for forage production, rely on daily purchase. In dry seasons, these peri-urban commercial farms cannot meet the forage requirements of city dairies. Due to the large gap between forage supply and demand, it is transported from irrigated areas hundreds of kilometres from some big cities. In rain fed areas wheat straw and sorghum/maize/ millet dry stalks are the bulk of feed. In addition to green and dry forages concentrates are fed to animals in milk.

Livestock rearing has evolved specialized crop management practices e.g. intercropping of companion crops, maize thinning and fallowing of land help to feed animals. Farmers in rain fed areas have developed cropping patterns in response to rainfall, moisture, manure availability, soil fertility, and forage requirements. Of all these factors rainfall is the most important. There are therefore, three very different fodder situations:

(i) First, in rain fed areas agriculture is for subsistence and crops depend on rainfall. Forage requirements are partly met through forage crops and partly by grazing fallows;

(ii) Second, in the irrigated tracts peri-urban forage production is mainly for commercial purposes, and

(iii) Thirdly, in high altitude mountain regions both forage production and stock rearing are for subsistence and forage requirements are partly met through cultivated forage on very small holdings where irrigation is available and partly through using alpine grazing to the maximum extent.

On the plains there are two very different types of stock rearing: subsistence and commercial; the latter in the peri-urban or "milk shed" areas of towns, with some even in town. There are also two levels of fodder production; some farmers grow for their own stock (again sub-divided for subsistence and commercial) while others grow fodder as a cash crop and may not have livestock. Commercial forage farmers practice very intensive cultivation and usually produce four crops per year from the same piece of land due to optimum temperatures, availability of irrigation, proper planting time and management, with application of balanced doses of fertilizers with different times of application to sustain soil fertility for maximum/early crop growth and productivity.

Commercial dairies are rare in the rural tracts but very important around big cities such as Karachi, Hyderabad, Lahore, Sheikhupura, Gujrat, Gujranwala, Rawalpindi-Islamabad, Faisalabad, Peshawar, Charsada, Nowshera, Quetta, and Mirpur, AJK. Feed for these dairies is transported by truck, tractor trailer, and camel/bull/donkey carts for forage produced nearby, but some is produced and transported from over 300-400 km away e.g., from Hyderabad/ Sukkar/Nawab Shah to Karachi; from Kasur, Sheikhupura, Gujranwala, Faisalabad, and Renala Khurd to Mirpur (AJK) and Rawalpindi-Islamabad, and from Nowshera, Charsada, Mardan, and Malakand to Peshawar. Cities in irrigated regions have relatively close forage sources, but Karachi, Islamabad-Rawalpindi, and Mirpur (AJK) must purchase feed from distances of 300-400 km. Buffaloes predominate in town dairies of Punjab, NWFP, and Sindh, as their milk is preferred to cow milk and fetches a higher price, essentially because of its higher fat content (8.5 vs. 4.5%). In Quetta, Balochistan, less than half of the urban herd is buffalo, due to several factors including lack of irrigation, scarcity of green and dry forage and because buffaloes require nearly twice as much forage and feed as cows. Afghan refugees brought their pure and cross Friesian cattle to Quetta with them and their excellent condition and performance has attracted local dairymen to cattle.

Rising transport costs have increased the making of oat hay. Data are not available, but huge quantities of oats are now regularly made into excellent hay, baled and transported over long distances. In the 1950s and 1960s, oats were grown for fodder, but mainly to make hay for horses, then the main transport animal in rural and urban areas.

The rapid rise in the popularity of oats over the last fifteen years has been due to the introduction of high yielding cultivars that provided several cuts, such as cvs Scott, S-81, Tibour, Cuscade, Swan, and PD2-LV65. In the late 1980s the dairy industry began to expand and more and more milk marketing outlets became available. A large number of milk processing units have been installed. The expanding urban population has provided a lucrative milk market and dairy farming is now better managed.

Forage production is an important business especially near big cities; a range of crops are grown to maintain a year-round supply. Improved, multi-cut oats are very popular in urban irrigated areas such as Kasur, Sheikhupura, Gujranwala, Faisalabad, and Renala Khurd (Punjab); Nowshera, Charsada, Mardan, and Peshawar (NWFP); and Hyderabad, Sukkar, and Nawabshah in Sindh. Oats have almost replaced the poor quality wheat and rice straw that was the basis of winter feed; berseem provides very high-quality cool season forage and is marketed in vast quantities, but production tends to peak in spring and is poor in the coldest months – it cannot easily be made into hay. Improved oats provide forage in cold weather when other green feed is scarce and are replacing the forage brassica which were formerly used in the winter gap (Suttie, 2000).

Nevertheless, forage yields are low compared to their potential. Improved cultivars and technology have been slow to reach the small scale farms which account for the bulk of forage production. Also seed production has lagged behind plant breeding and introductions. Recent medium scale on-farm work has indicated that yields can be raised two to three times with the use of available improved varieties and appropriate agronomic techniques. In an area where land and irrigation are the major limiting factors to enhancing fodder production, intensification is the only way to meet the country’s needs for livestock products and hence, forage.

3. FODDER OAT INTRODUCTIONS

Fodder oats were introduced during the early British era, but it was only in the 1970s that 400 oats cultivars were acquired from Australia, Canada, Europe, New Zealand and USA. These included materials donated by NZ DSIR/NZ CFRI in 1979 and form the basis of Pakistan’s fodder oat improvement programme. Further commercial importations were made under the World Bank (Hill Farming Project) for Azad Kashmir in the 1980s. Some cultivars from this material still play an important role in the provision of green-feed or hay across a wide range of ecologies. The Fodder Research Programme, National Agricultural Research Centre (NARC), which has the national mandate in fodder improvement, also introduced several improved oat cultivars from Western countries in the mid 1980s. During the late 1980s, the FAO Afghan Programme arranged for fodder oat material to be multiplied with private seed companies in Pakistan, and under Government supervision at research centres.

[See the Annual Report of the Pakistan Agricultural Research Council (PARC) which includes the work of the National Agricultural Research Centre (NARC), Islamabad.]

The Fodder Research Institute, Sargodha , is the only research institute in the country to handle the need for seeds of improved or promising forages. It used to be a small station and Military Farm in the suburbs of Sargodha producing fodder for horses, mules, and milking animals for military needs. The Research Institute has 200 hectares of irrigated land for breeding, evaluation, screening, management, selection, and recommendation of forages suited to various agro-ecological conditions in general and especially for the vast irrigated areas of the country. Since the Institute has a relatively large area of irrigated land, seeds of almost all the improved or promising forage cultivars are multiplied.

The Institute has sub-stations in Faisalabad and Bahawalpur for screening under different climatic conditions. Due to easy availability and access of the farming communities to seeds of improved forages, especially oats in Sargodha and Faisalabad, both cities have now become a major source of fodder as a cash crop which is transported and traded in large quantities and hauled over great distances throughout Punjab. The forage cultivars (oats and others) released by the Fodder Research Institute, Sargodha and other research stations are listed below:

Forage crops cultivars released by various Institutes in Pakistan

Crop/cultvar Institute/Station Year of Release

(i) Oats

(ii) Barley

(iii) Berseem

(iv) Maize

(MaizexTeosinte)

(v) Millet

(vi) Sorghum

(vii) Sorghum-Sudan grass Hybrid

______________________________________________________________________

The Fodder Research Institute(FRI) Sargodha CCRI which works under the Ayyub Agricultural Research Institute, Pirsabak, NWFP (Cereal Crops Research Institute, Pirsabak, NWFP), AARI, Faisalabad (Ayyub Agricultural Research Institute, Faisalabad) MMRI, Sahiwal (Maize & Millet Research Institute, Sahiwal), RARI, Bahawalpur (Rainfed Areas Research Institute, Sahiwal).

Improved oats from Sargodha, other research centres and private seed companies have been grown and used routinely by farmers, usually around big cities (from where fodder is transported daily for sale to private and government commercial dairy units and army dairy farms) in lowland rain fed areas, as well as in mountain areas with extremely limited land holdings and irrigation facilities, for some 20 years. In October-November the summer fodders are finished and most winter forages are not yet ready for harvest so there is an acute shortage of fodder. Oats provide assured feed early in the winter if sown at the end of August or beginning of September to be cut at the end of November - beginning of December.

Oat Seed Multiplication and Extension:

The Fodder Research Programme, National Agricultural Research Centre (NARC), Islamabad is responsible for introducing the seed of almost all the new varieties of various forage crops in Pakistan. All the introduced forage crop varieties are evaluated for forage and grain yield traits at NARC, Islamabad.

In the meanwhile, seed is multiplied for further evaluation. Based on the initial yield evaluation and performance data, some promising introductions are selected for evaluation and multiplication in different agro-ecological zones. The Fodder Programme NARC has forage evaluation and multiplication cooperative substations in the four provinces of the country. The selected cultivars are further evaluated in national uniform evaluation trials at all substations under the supervision of scientists from the NARC, Islamabad. As most of the forage research substations have sufficient area for seed multiplication, those cultivars suited to their agro-ecological region are initially multiplied at these stations. Also, the Fodder Programme, NARC, Islamabad and Fodder Research Institute Sargodha have larger areas for seed bulking; therefore, the maximum quantities of all the selected oats are multiplied by both programmes. The seed thus bulked is sold to small farmers, commercial growers, both Government and private dairy farms and other agencies/organizations interested in improved oat fodder production and development.

In Pakistan, most of the seed of improved forage and grain crops is usually multiplied by private seed companies, Government Research and Extension Centres and to a limited extent by commercial growers. The seed thus multiplied is sold to the interested growers throughout the country. The bulk of the improved seed is mainly purchased for seed multiplication in the irrigated regions and the surplus quantities of seed is sold to the private dealers who transport the seed for sale in rural areas. These private local seed dealers are the main source of supply of improved oat seeds to the small as well as big commercial farmers.

In the near past, no small farmer knew about the potential of forage oats cultivars for livestock and never grew oats. Under the Productivity Enhancement Project in 1997-98, large scale demonstrations and seed multiplication of improved oats was done on farmers’ fields throughout the country. Village seed producers were linked with the private seed companies and private seed dealers in all cities for sale and purchase of improved oats seed. The seed companies and seed dealers became a major source of future oats seed bulking and so improved its availability to the small farmers and seed producers. The seed procured by the seed and private dealers in almost all the big towns is now regularly bought and sold in local markets in the rural areas. Most farmers save a lot of their own seed from the initial supply from the seed merchants.

Also, the non government organizations such as National Rural Support programme (NRSP), Sarhad Rural Support Programme (SRSP), Punjab Rural Support Programme (PRSP), and Balochistan Rural Support Programme (BRSP) are working at grass root level in rural areas over almost 70 % of the country. These rural support programmes played a very important role in demonstrating improved forage crops, especially oats. Interested communities indicate their needs for seeds of oats and other improved crops. The representatives of rural support programmes arrange procurement from reputable sources and deliver it to the farmers homes. In this way seed of improved oats became accessible to the small farmers at the village level. This has helped in the quick dissemination of improved oats seeds, even in the remote areas throughout the country.

For the last several years, the Fodder Programme NARC, and private seed companies have been actively involved in the seed multiplication of improved oats for the FAO Afghan Programme for use in Afghanistan.

4. THE ROLE OF OATS

Forage oats (Avena sativa L.) are grown throughout Pakistan in winter under a wide variety of soil and climatic conditions. Improved oats cultivars are now the main source of winter and spring forage in the plain irrigated / rain fed and high altitude (1000-2300 m asl), colder regions, especially in the Northern Areas. They are grown on more than 35 percent of the available arable land under forage crops throughout Pakistan. Grain yields vary from 2.4 to 3.2 tons/ha in the better environments, but less at higher altitudes (2,300 m). In Northern Areas at an altitude of 2,000-2,300 m, the highest recorded green fodder yield ranged from 80-120 tons /ha.

It is an especially important crop in the plains during the cooler autumn, winter and spring months and in the mountains during autumn, spring and early summer. Reported green fodder and dry matter yields are generally higher in some parts of the North West Frontier Province (NWFP) and Balochistan provinces than in the lowlands and mid hills (up to three times higher through the use of locally bred or selected cultivars of western origin), due mainly to better inherent soil fertility combined with the widespread use of chemical fertilizers, farm yard manure and higher incoming radiation (less fog and cloud cover). In the Northern Areas, oats have proved to be invaluable for feeding milking animals especially the stall-fed cattle near or around villages and the bigger cities (such as Gilgit and Chilas, Skardu to meet domestic milk needs), and hence, not able to use traditional grazing lands.

Temperate and cool sub-tropical conditions are congenial for the growth of oats. A well distributed rainfall of 400 mm and an optimum temperature range of 16-320 C from September to April are sufficient to meet its requirement as a fodder crop. Oats can provide green fodder after 60-70 days in an emergency to tide over the scarcity period, but in 90-100 days after germination, large quantities of fodder are produced. Oats are mostly fed green, but any surplus is made into hay. It is a favourite feed of all animals and the straw is soft and much superior to wheat and barley. It is high in total digestible nutrients (TDN), digestible crude protein, fat, vitamin B1 and minerals such as phosphorus and iron. The oat grain is a particularly valuable feed for horses, dairy cows, poultry and young breeding animals of all kinds.

Improved oats have been especially successful for stall-feeding across a wide range of altitudes, climates and ecologies from 400 m to higher than 2,300 m. In the plains fodder oats are grown for dairy cows and buffaloes kept in and near big cities to meet the considerable milk demand; so much of the area under fodder oats is near large cities, and on military and private dairy farms. Forage (including crops other than oats) is transported daily to the cities and sold to feed milch cattle and horses kept for urban haulage.

5. FORAGE OATS IN THE NORTHERN AREAS

New oat cultivars were first introduced to the Northern Areas by the fodder component of FAO Project PAK/86/027, Gilgit. They have proved to be valuable in the Northern Areas, since they grow much earlier and more vigorously than the traditional winter cereals. Green oats is cut in Gilgit and Chilas when no other green feed is available. Higher yields (up to three times) are produced in the 1,000 to 2,300 m band compared to lower altitude zones, possibly reflecting better agro-ecological adaptation. Many cultivars have been positively evaluated at different altitudes in winter in lowland areas through to high alpine areas around 2,300 m.

Feeding of green oats to cows in winter increased milk yields from 1 to 4 litres per day. Not all milk is sold; additional production increases family dietary quality over traditional practices, especially important for the young and aged. (Milk and dairy products are valued constituents in Pakistani diets). Fodder oats, vetch, lucerne, shaftal, and berseem seed are produced for further cultivation, barter and sale to earn extra cash for household requirements.

6. INFORMATION ON FODDER OATS (MAINLY) FROM OTHER COUNTRIES

6.1. Characterization of a dual-purpose crop:

Hadjichristodoulou (1983) described a dual-purpose crop as one suited to use as "grazing plus hay" or "grazing plus grain", Yau and Mekni (1985) classified dual purpose barley cultivars (see Figure 1) as having high forage yield at grazing time and high grain yield after grazing. This was considered a "narrow-sense" definition; in the "broad sense", dual purpose barley should perform well whether grazed or not. Therefore both forage and grain material should be used as resource material in breeding dual-purpose cultivars. In Cyprus, Hadjichristodoulou (1983) concluded that high-grain-yielding lines could be used as basic material for selecting dual-purpose varieties. By contrast, Yau and Mekni (1985) reported that improved high grain yielding barley genotypes generally did not perform well when subjected to grazing. Anderson (1985), however, found no clear differences between dual purpose and forage cultivars in their response to grazing over years as reflected in dry matter and grain yield.

Grain yield after clipping grain type

 

dual-purpose type

 

forage type

Dry matter yield at tillering

Figure 1. Classification of barley genotypes according to their dry matter-yield at the tillering stage and grain yield after clipping (after Yau and Mekni, 1985).

6.2. Desirable features in a dual – purpose cereal crop:

A successful dual-purpose crop should provide a substantial amount of forage and recover quickly from defoliation so that a good yield of grain can be obtained. From the literature, it would appear that such a crop for southern Australia should have the following features:

- Semi-prostrate or prostrate growth habit

- Long pre-jointing phase

- Free-tillering habit

- Leaf canopy of relatively prostrate foliage in the early, pre-jointing phase, becoming more erect as stem elongation occurs and new leaves are higher in the canopy.

- Late flowering time i.e. long vegetative phase, flowering time controlled by a relatively strong response to vernalization. A photoperiod response may also be necessary with early sowing of even a strongly vernalizing type to ensure flowering after risk is passed.

These characteristics would allow early sowing, as soon as moisture is available, to take advantage of favourable conditions for photosynthesis in the autumn. Substantial herbage production should be achieved in the early stages of growth and could be safely grazed before flower initiation and stem elongation. If defoliation is not too severe, the type of plant envisaged should retain some leaf after grazing, and should be able to rebuild a canopy and re-tiller as necessary, so that when stem elongation occurs, an adequate number of fertile tillers should be present to ensure a good yield of grain. Because of late flower initiation due to the vernalization requirement, frost damage should be avoided, whilst with only a relatively weak response to photoperiod, flowering and grain production should not be delayed sufficiently for summer moisture stress to be a problem. Whether more than one grazing would be possible would depend on the degree to which various characteristics were expressed in particular cultivars and on environmental conditions and grazing management.

6.3 Forage Quality:

Cattle can be maintained in good condition on oats at a time of the year when the supply of other feed is scare and costly. Many cultivars provide good forage if cut at flowering or soon after. Broad-leaved cultivars produce a higher forage yield, but narrow leaved ones are preferred by horses and cattle. The demand for meat and dairy products is increasing due to the rapid population growth in Pakistan, so improvement of livestock production is urgently needed and quality forage plays a pivotal role. Although 16-19 % of the total cropped area in Pakistan is planted to fodder, animals are generally underfed. To operate an efficient and economical livestock industry, high yielding, nutritious and multi-cut fodder oats are needed to feed more animals (Dost, 1997).

Hussain et al., (1993) reported that ‘Fatua’ oats harvested at various intervals produced more fodder and less crude protein with plant age/advance in crop maturity. The crop should be harvested at a stage that provides an optimum compromise between forage yield and quality. Maximum green fodder and dry matter yields and crude protein contents were recorded when oats was harvested at 50 percent flowering. Hussain et al. (1994) also reported that the highest green and of course dry matter yields of five oat cultivars were at 50 percent heading.

Dost et al. (1994) concluded that forage yield, dry matter yield, and crude fibre increased while seed yield and crude protein declined with advancing maturity. Harvest at 50 percent flowering resulted in superior forage and dry matter yields with inferior nutritive forage value as determined by lower crude protein and higher crude fibre contents, compared to harvesting at the vegetative stage at 70 and 85 days after planting. Minimum forage and dry matter yields with maximum forage quality resulted from harvesting at the mid vegetative stage at 70 and 85 days after planting.Young cereal plants provide excellent quality herbage which is highly nutritious for lactating ewes and young growing lambs. Their digestibility, crude protein content, carotene, mineral and vitamin contents have been reported to decline with plant age, whereas crude fibre and nitrogen free extract increase (Skorda, 1977; Eagles et al., 1979; McDonald and Wilson, 1980). However, yield per unit area of both crude protein and digestible dry matter increase with advancing maturity until the milky stage (Hadjichristodoulou, 1976a & b; Hughes and Haslemore, 1984; Droushiotis and Wilman, 1987).

High quality feed, suitable for growth and lactation, should exceed values of about 67 percent in digestibility and 13 –15 percent in crude protein; less than 65 percent digestibility indicates feed suitable for maintenance only (Raymond, 1969; Hughes and Haslemore, 1984). Whilst Hughes and Haslemore (1984) concluded that if the digestibility of a forage is satisfactory (above 67.5 percent), the protein content will generally also be satisfactory (above 12-15 percent), Raymond (1969) and Eagles et al. (1979) found that decline in digestibility of forage crops (including cereals) led to a reduction in voluntary intake by animals.

Several workers (Lassiter et al. 1958; Zogg et al. 1961) report comparisons of maize and oat silage for milking cows. Both concluded that maize silage was superior to oat silage for milk production. However, in each study the silages were not fed alone and a considerable portion of the dry matter intake was from hay.

Mowat and Slumskie (1971) indicated that maize silage contained more digestible energy than barley silage when fed to finishing steers. The low digestible energy content of barley silage was also demonstrated by Fisher et al. (1972) in a study with dairy cows. Neither report assessed the suitability of the crops in terms of both field yields and feeding value.

Under Tasmanian conditions, Abdul-Rahman et al. (1985) found that very early-sown (4 January) oats still had a digestibility of 60 percent and crude protein content of 14 percent in June, when the crop was close to flowering. It is noteworthy that under the long growing season of high rainfall areas, crops always produce high dry matter digestibility (75-85 percent) in winter (Dann et al., 1977; Eagles et al., 1979). The relationship between digestibility, radiation and temperature has not yet been shown experimentally, but sunny days followed by cool or cold nights should give high levels of soluble carbohydrates (Wheeler, 1981). Whilst lower digestibility values were reported in low rainfall areas, crude protein content at later stages of crop development, by contrast, was higher (Skorda, 1977; Droushiotis and Wilman, 1987). This was attributed to less leaching of soil nitrogen in low rainfall areas (Hadjichristodoulou, 1976).

6.4 Maturity period:

Although grazing and cutting contribute to delay in flowering, a late flowering characteristic is important in dual-purpose cereals, in many places in high rainfall areas, to avoid the risk of frost damage . Through the findings of many researchers, time from sowing to heading or maturity is a good indicator for the selection of dual-purpose crops. In the high rainfall areas of Punjab, the recommended dual-purpose oat cultivar S-81 was the earliest to mature after heavy grazing/cutting. It was, however, the latest when ungrazed and grown for grain (Dost, 1994). This trait of late maturity in a dual-purpose crop was confirmed by McLeod et al, (1985) with a cutting height in oats of 2 cm. Hadjichristodoulou (1983) and Yau et al., (1987) concluded that dual-purpose lines tended to be later heading than the usual grain types. Furthermore, the time to heading or maturity appeared to be the main factor affecting yields, while tiller number, head number and plant height were less important (Yau et al., 1987). But these authors warned that, although late lines had better recovery to produce high grain and straw yields after simulated grazing, they were not good dual-purpose types since they gave little at the time of defoliation.

6.5 Factors affecting the response to date of sowing:

The response to early sowing is apparently a valuable criterion of a dual-purpose crop. This advantage in high rainfall areas in Australia may be associated with a response to vernalization (Anon, 1986; Dann et al., 1977; Davidson et al., 1985a), which gives flexibility in sowing time with stability in flowering time. Varieties responding to long days (Davidson et al., 1985b), may show a similar delay in flowering and hence escape damage by water logging and frost.

Johnson and Dann (1984) suggested that further improvement for dual purpose use could come from breeding cultivars with a higher vernalization requirement, permitting flexibility in sowing dates from late summer to mid autumn without risk of frost damage.and it is very important in areas with prolonged freezing temperature especially in the high altitude regions. For many cereal growing areas, however, these cultivars should also be able to flower early in spring (little requirement for long photoperiod), so that grain is produced before the onset of early summer moisture stress.

Stern and Kirby (1979) stated that vernalization, photoperiod and temperature are the most important environmental stimuli on phenological events as they influence tillering, spikelet initiation and development of cereals. It is difficult to separate the effect of these factors on phenological events in cereals.

6.6. Effect of nitrogen fertilization on dry matter yield:

Many workers in Australia have found that nitrogen fertilization at various levels (ranging from 67 to 180 kg N/ha) increased the forage yield of oats and that this was a good method of overcoming winter feed shortages (Archer, 1969; Blunt and Fisher, 1976; Crofts, 1966a; Wheeler, 1968). A better response to nitrogen was achieved in spring when the temperature rose (Cook and Lovett, 1974).

Leaf area index (L), total living dry weight, stem dry weight and number of tillers were all significantly increased by nitrogen fertilizing of defoliated and non-defoliated oats (Cook, 1971). Mehra et al. (1971) found that fodder yield was positively correlated with plant height, leaf length and leaf width, tiller number, and stem girth.

The number of tillers at the end of stem elongation and the final number of tillers with ears in cereals were reported to be increased by the addition of nitrogen, especially when applied early, thereby increasing yield (Needham and Boyd, 1976; Graham et al., 1983; Garcia del Moral et al., 1984). A nitrogen deficit reduces tillering due to:

- Retarded appearance of lateral buds (Hewitt, 1963, cited by Garcia del Moral et al., 1984).

- Limited root growth (Briggs, 1978; Cook, 1971).

- Small weak shoots whose leaves contain reduced levels of chlorophyll and carotenoids (Briggs, 1978).

By contrast, however, some workers have demonstrated that nitrogen fertilizer neither increased dry matter yield significantly nor compensated for the deleterious effect of clipping on the grain yield of oats and barley. This might be due to one or both of the following reasons:

- Available soil nitrogen was already high (Dann, 1971), where the site had previously been under leguminous pasture (Spurway, et al., 1976), or a heavily manured crop (Gardner and Wiggans, 1960) or fallow (Brown, 1975).

- Nitrogen fertilizer was applied in early winter when the temperature was very low (Archer, 1969). Cook and Lovett (1974) suggested that the ambient temperature rather than nitrogen supply is the limiting factor in growth of oats during winter.

7. OAT RESEARCH AND INVESTIGATIONS IN PAKISTAN

The Co-ordinated Fodder Research Programme NARC, Islamabad vigorously evaluated 400 introduced cultivars (1970s introductions) throughout Pakistan and selected 20 promising ones based on maximum forage yield, dry matter yield, maturity etc. The 20 selected cultivars were further evaluated in all four provinces in the autumn (rabi) season under a wide variety of soil and climatic conditions to select and recommend the most promising and suitable ones for different areas within diverse agro-ecological regions. The variation in environmental conditions in different agro-ecological regions is well known to plant breeders. Fluctuations in rainfall and temperature are neither consistent nor predictable from year to year or from place to place. Fertility status and soil types also vary throughout the country. Serious losses in forage yields due to drought, disease, and insects are common in many areas.

Pakistan has a long history of selecting and using local oat landraces, and in modern times, especially the last twenty years, breeding and testing of improved cultivars incorporating material from western sources into local fodder programmes has been a continuous process. Year-round fodder production is the most important component in the farming systems and a great deal of research is being carried out in the four provinces of Pakistan as part of a national coordinated fodder research programme. The details are presented below.

7.1 Genotype x Environment Interaction and Screening Methods:

Considerable genotype by environment interaction has been noted across latitude, altitude, seasonal sequence, with some cultivars producing significantly better forage yields than others in certain environments and management regimes. So far, this is poorly documented and has only been modestly exploited in Pakistan due to limited local resources. Effectiveness of varietal testing programme is influenced by several factors. These include experimental design, the number of locations, and the number of years used to average variety means. Information is required as to whether forage oat varieties respond differently when planted under diverse environment interactions, and if so, how important such genotype x environment interactions might be in an oat variety evaluation and selection programme.

Horner and Frey (1957) report that dividing the Iowa State into 2, 3, 4 and 5 sub-areas would reduce variety x location interaction effects by 11, 21, 30 and 40 percent respectively and hence increase the efficiencies of the state wide oat performance trials.

Liang et al. (1966) studied genotype x environment interaction in wheat, barley, and oats and recommended dividing Kansas into 3 and 4 areas, for barley and wheat testing, respectively. It was concluded that it was not necessary to divide the state into smaller areas for oat testing.

Dost et. al. (1993) studied the optimum allocation of resources in varietal evaluation for 13 oat genotypes for forage yield at 4 locations for 4 years and suggested that the three provinces under study should be divided into sub-areas on the basis of variation in rainfall, temperature, soil type, and soil fertility in order to minimize genotype x environment interaction for an efficient forage oat evaluation programme (Table 1).

Table 1. Expected Variance of a Variety Means (Vx) for various assumed Numbers of Replicates and Locations per Test.

No. of replicates

No. of years

2

4

No. of Locations

No. of Locations

2 4 6 8 10 12 2 4 6 8 10 12
2 2.25 1.29 0.97 0.81 0.71 0.65 1.18 0.67 0.50 0.42 0.37 0.34
3 2.22 1.27 0.96 0.80 0.70 0.64 1.16 0.67 0.50 0.42 0.37 0.34
4 2.20 1.26 0.96 0.79 0.70 0.64 1.16 0.66 0.50 0.42 0.37 0.33
5 2.19 1.26 0.95 0.79 0.70 0.64 1.15 0.66 0.50 0.42 0.36 0.33
6 2.18 1.26 0.95 0.79 0.70 0.64 1.15 0.66 0.50 0.41 0.36 0.33

Dost et al. (1993)

To evaluate the importance of genotype x environment interactions, De Pauw et al. (1981) compared three cultivars of wheat, three of oats, and three of barley for four years at five locations in north-western Canada. They concluded that cultivars showed differential responses in specific environments, which can be used to determine areas of cultivar adaptation.

In a study on genotype x environment interaction at twenty-seven locations for five years, in Alberta, Canada, Kibite et al. (1988) suggested the need to divide Alberta into six rainfed and two irrigated areas.

7.2 Oats as a multi-cut crop:

Compared with wheat and barley, the traditional sources of arable green winter fodder in Pakistan, oats provide multiple cuts, tiller profusely and yield more, and are of higher nutritional value. A major reason for this is that the standing oat crop can be harvested progressively, releasing land earlier than normal for follow-up crops or relay cropping. Late in the season, any remaining crop can be cut at the farmer’s discretion and dried as hay. This coincides with optimum soil moisture for land cultivation and planting of the following crop. This also allows small areas or peripheral lines on terraces to be saved for seed production. In many, but not all instances, more recently bred cultivars out-yield older ones (Dost et al. 1994).

Although the utilization of oats as a multi-cut crop is a common practice in Pakistan, relatively little research data are available to aid the farmer in the selection of the best forage harvest schedule for the dual utilization of oats to allow one to obtain high forage yield, grain yield, and good forage quality.

Bhatti et al. (1992) evaluated 13 oat cultivars under a two cut system at NARC, Islamabad during 1985-86 and 1986-87. The results of the study revealed that the cultivars PD2LV65 and S-81 produced 28.05 percent and 26.24 percent more green forage yield and 26.30 percent and 21.93 percent more dry matter yield respectively in two cuttings compared with the control variety. Thus oat cultivars PD2LV65 and S-81 were found suitable for multi-cut systems both under irrigated and rainfed conditions (Table 2).

Table 2. Green and dry matter yield of various oat cultivars at the National Agricultural

Research Centre, Islamabad during 1985-87 (average of two years)

Cultivar First Cutting Green fodder yield 2nd cutting Total Percentage increase (+) decrease (-) over control First cutting Dry Matter yield 2nd cutting Total Percentage increase (+) or decrease (-) over control
‘DN-8’ 27.15 ab 45.99c 73.14 + 7.22 5.185 17.936 23.121 + 6.31
‘Algerian’ (control) 25.46 ab 42.75cd 68.21 - 4.862 16.886 21.848 -
‘W. No. 11’ 23.30b 42.28cd 65.68 - 3.85 3.984 16.892 20.876 - 4.01
‘Avon’ 23.76b 45.21cd 68.97 + 1.11 3.944 17.632 21.576 - 0.79
‘Fulgrain’ 27.47ab 44.75cd 72.22 + 5.88 5.246 17.452 22.698 + 4.37
‘Sargodha-81’ 29.32a 56.78a 86.10 + 26.24 5.893 21.576 27.469 + 26.30
‘Golden rein’ 29.16a 43.67cd 72.83 + 6.78 5.103 15.502 20.605 - 5.25
‘Swan’ 26.85ab 49.84b 76.69 + 12.43 5.235 17.792 23.024 + 5.86
‘PD2-LV65’ 29.32a 58.02a 87.34 + 28.05 5.805 20.713 26.518 + 21.93
‘Kent’ 28.40a 45.37cd 73.77 + 8.15 4.629 16.424 21.053 - 3.19
‘Java Lahori’ 27.77ab 41.51d 69.28 + 1.56 4.804 15.151 19.955 - 8.24
‘A. fatua’ 26.85ab 45.37cd 72.22 + 5.88 4.994 16.877 21.871 + 0.56
‘Ealge No. 1 25.00ab 44.14cd 69.14 + 1.36 4.550 16.552 21.102 - 2.97

Means followed by the same letters do not differ significantly at 5 % level of probability.

Bhatti et al. (1992)

7.3. Oats as an intercrop/companion crop:

In order to obtain early and good yields under small land holdings and severe winter conditions, compatible fodder crops of different types might be planted in mixture to produce high fodder yields and forage quality per unit area per season (Table 3). The leguminous dwarf fodders like berseem/vetch can be mixed with tall growing fodder like oats, rye grass, brassica etc.

Oat + vetch and barley + vetch combinations produced on average 110 and 70 tons/ha of green material compared with 100 and 56 tons/ha pure oat and barley stands respectively within the 1400 to 2000 m altitude band (Table 3).

Table 3. Green and dry matter yields (tons/ha) of

oats, barley and vetch during 1994-1997

Cultivars

Sites

Gilgit Chilas
Green yield Dry yield Green yield Dry yield
Oats 100 21 105 23
Oats + vetch 110 24 102 22
Barley 56 12 59 14
Barley + vetch 70 16 76 18

Also a deep-rooted crop like Lucerne can be mixed with shallow rooted crops like oats, rye, barley or brassica. The annual fodder is usually planted in the space between the rows of perennial odder. This technology has been practically demonstrated to the farmers of the Northern Areas. There are many advantages of mixed planting over sole planting:

- More than one crop per season per unit area

- Weed control is easier

- More fodder yield and better quality of fodder

- Maintains and improves soil fertility.

Oats were inter-cropped in winter active Lucerne and red clover planted in rows spaced at 30 cm apart at a number of locations. The mixture of Lucerne + oats, red clover +oats, and berseem + oats produced maximum green and dry matter yields as compared to the sole crops of either legume. The results are presented in Table 4.

Using oat + berseem mixtures provided early and more fodder yields, increased milk production by 20 litres per animal per month on average, compared with traditional practices. At the same time, the demand for purchased concentrates was reduced by 20 kg/month per animal and milk production was extended by an extra two months (Table 4).

Table 4. Green and dry matter yields (tons/ha) of various legumes

and oats cultivars at Gilgit during 1993-1994

Treatments Forage yields Dry matter yields
Lucerne alone 70 18
Lucerne + Oats 115 30
Berseem 80 17
Berseem + oats 135 30
Red clover 63 16
Red clover + oats 94 26

To overcome the problems of fodder shortages due to limited land holdings and also to obtain maximum fodder per unit area per season, multiple cropping/ mixed planting techniques were tried. The details are presented below.

Non-winter-dormant Lucerne cultivars (Sundar being the main one), introduced by the FAO project PAK/86/027, Gilgit, have been very successful (Table 5). In some cases they may suffer some frost damage at high altitudes, but they grow throughout the year and yield more than twice as much as the landraces in the low altitude double crop areas 2000 m and below. The new cultivars also provided maximum green feed in the critical December-January period when traditional crops are usually dormant and the area experiences a fodder deficit period.

Table 5. Effect of mixed planting on green and dry matter yields (tons/ha) of lucerne, red clover, and oats in 1996-97

Treatments

Sites

Sultandabad

Rahimabad

Saling

Green yield Dry yield Green yield Dry yield Green yield Dry yield
Lucerne Sundar

110

30

105

26

68

20

Red clover

60

16

62

18

50

13

Oats

100

32

95

30

80

26

Average

90

26

87.33

24.66

66

19.67

Lucerne + oats

140

39

136

37

102

30

Red clover + Lucerne

115

32

108

26

70

22

Red clover + oats

90

26

93

28

75

23

Average

115

32.33

112.33

30.33

82.33

25

Pendleton (1957) reported that oats seeded at a low rate in 32 inch rows as a sole crop returned 190 bushels for each bushel seeded, compared to the 42 bushel return from a regular seeded 8 inch row spacing inter-seeded with clover. Also red clover inter-seeding reduced spring oat grain yields but increased the test weight. Reductions in oat yields due to the presence of clover increased as oat row width increased. The yields were reduced 7, 10, 14, and 18 percent respectively for the 8, 16, 24, and 32 inch row spacing. Reduced yields of oats were attributable to the companion clover and were 17 percent in 1954, 7 percent in 1955, and 12 percent in 1956.

7.4 Effect of Harvesting Stages on Forage Yield and Quality:

In feeding ruminants the nutritive value of the roughage is important from the economical production viewpoint of meat and milk, the formulation of rations, the feeding and management of animals on pasture or on other forage systems for maximum meat and milk production, and accurate interpretation of performance records of animals fed rations containing large amounts of forage. The use of roughage as a feed for ruminants depends on the age of the animal and the purpose for which it is fed, the amount of roughage consumed, and its chemical composition, digestibility, balance of nutrients, and economy.

It has long been recognised that the stage of maturity at which a plant is harvested is one of the most important factors influencing its chemical composition and nutritive value.

Extensive reviews on the importance of roughage quality in ruminant rations have been made by Huffman (1939, 1953), Reid et al. (1959), Van Riper and Smith (1959), Sullivan and Garber (1947) and Stallcup et al. (1956) have reviewed the literature on the influences of the stage of maturity on the nutritive value of certain plants.

Newman (1894) studied the influence of stage of maturity of rye on the chemical composition of the plant under Arkansas conditions. In the period from the boot to the blossom stage, crude protein decreased and crude fibre increased. Rosen et al. (1953) studied the crude protein of oat forage from November through March. Early growth in the autumn was much higher in protein than were later clippings.

Thurman et al. (1957) have reported on the chemical composition of the oat plant from April through June. In general, crude fibre increased with advancing maturity and protein was reduced. Digestion trials were conducted on silages harvested at the boot, milk, and hard dough stages of maturity. The total digestible nutrients decreased from 71.3 to 58.8 percent from the boot to hard dough stages. Stallcup (1958) published a preliminary report on the change in composition of some forage plants at different stages of maturity.

The apparent influence of ash and the buffering capacity of plants on rumen pH has been reviewed by Cason et al. (1954). The influence of lignin on digestibility has been reviewed and data on some forages have been published by Stallcup et al. (1956). The composition of crude fibre in several forage plants has been shown to vary widely by Stallcup (1958). Meyer et al. (1957) made detailed studies of the changes in composition and nutritional value of oat forage with stage of maturity under California conditions. Austenson and Law (1958) undertook an extensive review of literature pertaining to the effect of fertilizer on chemical composition of pasture herbage.

Little information is available in Pakistan on forage yield and quality in oats, barley, and wheat crops harvested at various stages of maturity. Studies were thus carried out to determine an ideal maturity/harvesting stage to obtain a compromise between maximum forage yield and a reasonably good forage quality.

Hussain et al. (1998) evaluated oats, barley, and wheat for forage yield and quality at nine maturity stages at NARC, Islamabad during 1990 –1992. It was observed that oats harvested at head emergence stage, and barley and wheat at 100 percent flowering stage produced maximum green forage yields. In all three crops the highest dry matter yield was recorded at early dough stage. The maximum crude protein content was recorded at 4-leaf harvesting stage repeatedly, whereas the minimum protein contents were recorded in the early dough stage. Oats, barley, and wheat harvested at boot stage provided a good compromise of green fodder yield, dry matter yield, and forage quality. At this stage a sufficient quantity of fodder with moderate forage quality was obtained (Table 6). Recent work on oats is reported by Hussain et al. (2001).

Table 6. Green fodder yield, dry matter yield and crude protein contents of oats,

barley and wheat under various cutting stages

Cutting stages Green fodder yield (t/ha) Dry matter yield (t/ha) Crude Protein percent
Oats Barley Wheat Mean Oats Barley Wheat Mean Oats barley Wheat Mean
CS 1 37.66 33.15 21.73 30.84 5.81 4.80 3.93 4.85 14.93 13.47 12.56 13.65
CS 2 40.43 35.74 26.26 24.15 7.13 5.75 4.78 5.89 14.07 12.78 11.97 12.34
CS 3 56.45 44.77 24.49 41.90 10.68 7.49 4.67 7.61 12.65 11.70 11.53 11.36
CS 4 67.16 51.30 28.80 49.09 12.41 9.21 6.52 9.39 10.80 9.85 10.21 10.28
CS 5 69.44 48.45 31.78 49.89 12.15 8.05 7.41 9.21 8.75 8.42 8.15 8.44
CS 6 64.60 56.39 30.66 50.55 11.43 10.26 7.08 9.59 8.10 7.72 7.50 7.77
CS 7 68.21 58.42 40.51 55.71 13.35 11.17 9.83 11.44 7.63 7.54 7.32 7.50
CS 8 64.27 53.93 33.95 50.72 13.99 13.40 10.83 12.74 7.50 7.02 6.96 7.16
CS 9 51.21 42.52 33.72 42.52 17.17 14.67 12.23 14.69 7.15 6.85 6.75 6.92
Mean                 10.17 9.22 9.48  

Hussain et al 1998.

CS 1 = Repeated cuttings at 4-leaf, CS 2 = Repeated cuttings at tillering

CS 3 = Repeated cuttings at jointing, CS 4 = Repeated cuttings at boot

CS 5 = Harvesting once at head emergence, CS 6 = Harvesting once at 50 percent flowering

CS 7 = Harvesting once at 100 percent flowering, CS 8 = Harvesting once at early milk

CS 9 = Harvesting once at early dough

Hussain et al (1995) conducted trials during 1990 and 1991 to evaluate yield and quality of fodder at different harvesting stages on oats and barley (Table 7). It was concluded that oats harvested at booting stage and barley at 100 percent flowering stage produced maximum forage yield (79.45 and 63.10 tons/ha respectively). In oat and barley crops, the highest dry matter yield (15.54 and 13.75 tons/ha) respectively was recorded at early dough stage. In both the crops crude protein contents decreased with the advance in crop maturity. The maximum crude protein content (14.93 and 14.37 percent) in oats and barley respectively was observed when the crops were harvested repeatedly at the 4-leaf stages, whereas the minimum was at the early dough stage in both crops. Oats and barley harvested at booting stage proved better for reasonable forage yield (67.32 tons / ha), dry matter yields (11.66 tons/ha) and forage quality (crude protein 10.33 percent). At this stage a sufficient quantity of forage yield with moderate quality was obtained in both crops (Table 7).

 

Table 7. Green fodder and dry matter yields and crude protein of oat and barely as affected by cutting at different stages

Cutting stage Green-fodder yield (tons/ha) Dry-matter yield (tons/ha) Crude protein ( percent)*
Oats Barley Mean Oats Barley Mean Oats Barley Mean
CS 1 46.02 39.63 42.82 7.40 5.58 6.49 14.93 13.47 14.20
CS 2 51.39 42.04 46.71 9.23 6.91 8.07 14.07 12.78 13.43
CS 3 69.35 48.68 59.02 12.63 8.26 10.45 12.65 11.70 12.18
CS 4 79.45 55.19 67.32 13.96 9.37 11.66 10.80 9.85 10.33
CS 5 72.69 51.16 61.92 12.66 7.39 10.02 8.75 8.42 8.59
CS 6 70.98 54.95 62.96 11.48 10.00 10.74 8.10 7.72 7.91
CS 7 77.78 63.10 70.44 14.18 11.12 12.65 7.63 7.54 7.59
CS 8 73.26 58.22 65.74 14.09 11.70 12.90 7.50 7.02 7.26
CS 9 51.97 45.72 48.84 15.54 13.75 14.64 7.15 6.85 7.00
LSD(P=0.05) 10.47 7.40   2.94 2.08        

* Data for one year

Hussain et al 1995

CS1= Repeated cutting at 4-leaf; CS2= Tillering;

CS3= Jointing CS4= Booting stage;

CS5= Harvest once at ear emergence; CS6= 50 percent flowering;

CS7= 100 percent flowering; CS8= Early milk

CS9= Early dough stage.

Lawes and Jones (1970) investigated the ensiling characteristics of barley, wheat, and oats crops cut at two different dates and reported that dry matter yields increased until the end of July. Digestibility and crude protein content declined until mid July when values of 56-60 and 6-7 percent for the barley and wheat and 53-55 and 5-6 percent for the oats respectively were maintained. Crops of all varieties were suitable for ensiling at maximum yield.

Brundage and Sweetman (1967) have recommended that oat/pea forage be harvested in the late milk stages of oat maturity to take advantage of higher yields of lower moisture silage. Bolsen et al. (1976) and Polan et al. (1968) recommended harvesting small grain forages at the dough stages of maturity. Comparing oat forage ensiled at the boot, early milk, and soft dough stages of maturity, Martz et al. (1959) recommended harvesting at the boot stage or soon thereafter.

7.5 Oats as a dual-purpose crop:

Seed production is a major problem with the majority of forage crops as most of them are harvested and fed to livestock well before seed formation, unless intentionally kept for seed. Therefore, development and cultivation of dual purpose forage crops varieties could be one of the best options/solutions for seed production and availability. The most common cereal grown as a dual-purpose (harvesting/grazing plus grain) crop in Pakistan is oats.

Dost et al. (1994) evaluated oat cultivar S-81 under different maturity/ harvesting treatments during 1991-92 at NARC, Islamabad (Table 8). It was reported that forage yield, dry matter yield, and crude fibre increased while seed yield and crude protein declined by harvesting the crop with advances in maturity. Maximum forage and dry matter yields with considerably inferior quality forage (as determined by lower crude protein and higher crude fibre values) were observed at 50 percent flowering stage. Minimum forage and dry matter yields with superior quality forage were recorded in the crop harvested at 70 and 85 days after planting. The results of this research also indicated that it is possible to have a satisfactory forage yield, forage quality and grain yield from oats crop that has already been harvested once for forage at 115 days after planting.

Table 8. Average Plant Height (PH), Tillers/Plant (TL), Leaves/Tiller (LV), Green Fodder Yield (GY), Dry matter Yield (DY), Seed Yield (SY), Crude Protein Contents (CP), and Crude Fibre Contents of Oats cultivar S-81

Cutting treatments PH TL LV GY DY SY CP CF
CT 1 63.63 d 6.18 c 4.89 c 13.59 d 2.07 d 0.85 b 12.29. a 22.32 d
CT 2 83.70 c 6.80 ab 5.89 b 16.92 d 2.57 d 0.54 c 12.25 a 22.94 c
CT 3 90.06 bc 6.89 ab 6.26 ab 23.46 c 4.08 c 0.48 8.68 b 24.50 b
CT 4 94.74 b 7.07 a 6.59 a 33.33 b 6.60 b 0.46 8.46 25.58 a
CT 5 134.78 a 6.46 bc 6.56 a 54.99 a 12.99 a - 7.94 25.60 a
CT 6 - - - - - 1.34 a - -
LSD (0.01) 10.70 0.54 0.63 4.73 1.24 0.24 0.34 0.36
Means followed by the same letters do not differ significantly at 1 % probability level.Dost et al. (1994)

CT1= Cutting for fodder after 70 days of planting and then for seed,

CT2= Cutting for fodder after 85 days of planting and then for seed,

CT3= Cutting for fodder after 100 days of planting and then for seed,

CT4= Cutting for fodder after 115 days of harvesting and then for seed,

CT5= Cutting at 50 percent flowering for fodder only,

CT6= No cutting for fodder but for seed only.

Tilt (1965) reported that skilled grazing management of dual-purpose oats has a big effect on ultimate grain yield. Early sown oats can be grazed from the end of April through to August when they are either ploughed under or "shut up for grain". The later the grazing continues, the more the grain yield is likely to be depressed. In 1964, a plant breeding programme to develop a dual-purpose variety adapted to Tasmanian conditions was initiated by the Department of Agriculture and resulted in the release of "Esk" in 1975 for all Tasmanian areas (Vertigan 1975). "Esk" is now the most common oat variety in Tasmania, and is normally sown between February and April. It is used for winter grazing by sheep and, depending on the farmer’s requirement for stored (conserved) feed, may be harvested for hay or grain. It is late maturing, resistant to most diseases and to grain shedding (Vertigan, 1975).

Smith (1960) found that the analysis of oat forage indicated that the percentages of protein, fat, ash, P, Ca, K, and nitrate declined from early growth to maturity while the percentage of fibre increased until the heads were emerging from the boot, and then decreased. The yields per acre of dry matter and of protein, ash, P, and Ca, constituents important to animal nutrition, increased steadily to a stage of growth when the seeds were nearly ripe and then decreased. However, a high proportion of the total yield per acre of protein, ash, P, and Ca was produced at early dough, the stage of growth often indicated as the best stage to harvest for hay or silage.

Forage stand losses resulting principally from lodging of oats and volunteer growths from shattered seed have promoted widespread interest in the harvesting of oats at immature stages of growth as pasture, silage, or hay. Chemical analyses (Berry 1920, Fagan and Watkin 1931, Keitt and Tarbox. 1912, Meyer et al. 1957, Nicholson 1957, Smith and Ross 1943, Sotola 1937, Thurman et al. 1957, Underwood and Moir 1944) and limited feeding trials (Meyer et al. 1957, Sotola 1937) have shown that oats at immature stages of growth can provide nutritious and high quality forage. The most complete studies of the changes in composition of oats from early to late stages of growth have been made by Berry (1920) in Scotland and by Sotola (1937) in the state of Washington, USA. However, many of the analytical studies have been made at only the more advanced stages of growth (Fagan and Watkin 1931, Keitt and Tarbox 1912, Nicholson 1957, Thurman et al. 1957, Underwood and Moir 1944) or have been made for only a few chemical constituents (Henderson and Davis 1955, Meyer et al. 1957, Smith and Ross 1943).

Several investigations have shown that grazing or clipping of small grain stands can provide, in addition to grain, high quality forage and reduced lodging. However, clipping frequently decreased subsequent grain yields (Gardner and Wiggins, 1960, Crowder 1953, Cutler et al. 1949, Thakur and Shands 1954, Washko 1947, Welton and Morris 1931, Westrate and Grafius 1958). The effects obtained have varied with the soil and climatic conditions (Cutler et al. 1949, Sprague 1954), nitrogen fertilization (Morris and Gardner 1958), and with the date of clipping.

In Saudi Arabia, Farnworth and Williams (1977) planted oats, barley, and wheat crops for two cuts for forage followed by grain. The first cut for forage was obtained at a stubble length above ground of 2.5 cm and 12.5 cm. Oats produced the highest forage yields but lowest grain yields while wheat produced highest grain yields. Similarly oats produced higher yields of straw. It was also found that oats had higher protein, fibre, and ash levels than barley or wheat but lower carbohydrate levels. Barley had the lowest protein level and wheat the lowest fibre and ash levels.

7.6 Fertilization of winter forages :

Application of different doses of nitrogenous and phosphatic fertilizer produced substantially higher yields (at the five locations in Pakistan indicated in Table 9) than using no fertilizer or farm yard manure alone, especially on seriously depleted soils, which had been mono-cropped for many years with wheat/maize/ barley etc. Maximum forage yields were obtained through application of 150-75 N P kg/ha. at most of the locations under trial and was followed by 150-25 N P kg/ha (Table 9). However, increased usage of chemical fertilizer could not realistically be justified in many instances for economic and environmental reasons (Table 9).

Table 9. Green fodder yield of oats cultivar Scot (tons/ha) under different

fertilizer doses at various locations during 1999-2000

Fertilizer

N P kg / ha

Green Fodder Yield (tons/ha)
1

NARC Islamabad

2

ARI

Tandojam

3

ARI, Tarnab

4

ARI, Sariab

5

AARI Faisalabad

100-25 74.69 59.56 30.78 46.00 96.29
50-50 61.11 52.16 28.01 42.33 79.32
50-25 56.79 57.40 25.23 40.33 70.37
50-75 61.11 55.24 28.94 47.33 101.23
150-25 80.86 74.99 29.40 45.33 98.45
150-75 87.04 74.09 30.78 56.66 112.04
100-50 74.69 62.34 31.95 50.00 99.38
00-00 37.65 44.13 27.78 32.00 52.16
National Agricultural Research Centre, Islamabad

Agricultural Research Institute, Tandojam

Agricultural Research Institute, Tarnab, Peshawar

Agricultural Research Institute, Sariab, Quetta

Ayyub Agricultural Research Institute, Faisalabad

In India, Taneja et al. (1981) found that with the application of 120 kg N/ha to the oats and barley crops, the green fodder and dry matter yields increased significantly. For seed yields, however, the significant response was observed up to 80 kg N/ha. Also the application of 80 kg N/ha provided the maximum net profit of Rs. 4022.30/ha.

Available nitrogen is usually the limiting factor in dry matter production of winter forage (Crofts, 1966b), and oats and other small grain cereals have shown considerable increase in forage and grain yield due to nitrogen fertilization after grazing. The response will vary according to the temperature, soil type, soil fertility level, rotation system, irrigation, cultivar, date of sowing, time of nitrogen application and other environmental factors.

In USA, Ohm (1976) recommended that more extensive testing of potential new cultivars be undertaken to determine specific fertility x cultivar interactions. It was found that application of nitrogen resulted in significant increases in plant height, lodging score, percent protein, and yield in oat cultivars; it did not affect heading date or seed weight; and it reduced test weight. Short-strawed types increased in plant height more with nitrogen application than several taller cultivars although plant height increases were greatest for other tall types. Lodging scores of weaker-strawed cultivars did not always increase more with nitrogen application than those of stronger-strawed cultivars. Percent protein in certain low protein cultivars increased more than that of some high protein cultivars with fertilizer nitrogen. A given cultivar may not respond similarly to nitrogen in terms of percent protein and/or yield. More extensive testing of potential new cultivars to determine specific fertility x cultivar interactions was recommended.

In Australia, autumn sown oats has shown a large response in forage yield to nitrogen fertilization and irrigation, with economic benefits in reducing the winter-feed shortage (Crofts, 1966a, 1966b; Brown, 1975). Blackman (1936) showed that nitrogen can increase the growth rate of grasses when soil temperature at 10 cm is in the range of 5 -8 0C, as the slow release by bacteria of inorganic nitrogen from soil organic matter is limiting plant growth. Therefore, an application of nitrogen fertilizer after grazing a forage crop in winter should boost herbage production, make a second grazing possible or produce a substantial grain yield (Cook, 1971). Gill et al (1977) also found that application of nitrogen fertilizer up to 120 kg/ha increased fodder and crude protein contents.

Oat crops can use the available nitrogen very effectively. In other circumstances, it helps in weed control and reduces the incidence of the fungal disease take-all in wheat a major root disease of wheat, caused by Gaeumannomyces graminis var. tritici. (Brown, 1975; Anon, 1984)

Time of nitrogen application is also very important. Studies have revealed that the later the vegetative stage at which nitrogen is foliar-applied up to the bloom stage, the less is its effect on vegetative growth and the greater is its effect on grain protein. Foliar-applied nitrogen at or near heading has increased yield and percent protein (DeDatta et al., 1972, Sadaphal and Das, 1966, Seetanun and DeDatta 1973). Split application of nitrogen increased grain yield over single basal application in some cultivars by minimizing lodging (Seetanun and DeDatta 1973). Spratt (1974) suggested that NH4+N applied at the boot stage increased percent grain protein in wheat.

Cultivars adequately or amply supplied with moisture have been shown to respond differently to nitrogen (N) application. Some cultivars (Gardner and Rathjen, 1975) produced maximum yield at natural fertility, others showed a typical parabolic response to increased nitrogen, and still others gave increased yields up to 275 kg N/ha. Additionally, cultivars with optima at 0, 70, and 275 Kg applied nitrogen/ha had similar yields (Gardner and Rathjen, 1975). Larger yield increases and smaller grain nitrogen concentration increases were obtained with a high yielding, low nitrogen (low protein) cultivar than with a low yielding, high nitrogen cultivar (MacLeod and MacLeod 1975). However, under dry-land conditions in semi-arid regions, wheat (Triticum spp.) cultivars of different heights did not respond differently for yield to nitrogen application (Bauer et al. 1965, McNeal et al. 1971).

7.7. Effect of harvesting/grazing on forage and grain yield:

As little information was available on the economics of oat production in Pakistan, a study was undertaken on the economic aspects of oats harvested for fodder and fodder + seed at different harvesting intervals. Generally, farmers cut oats for fodder or grain alone but there is good scope to obtain both fodder and seed from the same crop.

Hussain et al. (1994) evaluated five cultivars of oats for fodder yield, seed yield, and gross income at different harvesting intervals during 1987-89 at NARC, Islamabad (Table 10a). The cultivars ’PD2LV65’, ‘S-81’, and ‘Swan’ produced maximum forage yield (58.59, 54.99, and 54.58 tonnes/ha) and gross income (Rs. 14750, 13800, and 13720 when harvested only for fodder at 50 percent flowering stage. The highest seed yield (2.19 tonnes/ha) and gross income (Rs. 12380/ha) were obtained from PD2LV65 harvested only for seed (see Table 10b). Swan cut for fodder after 70 and 85 days of planting and then left for seed produced respectively 2.04 and 2.07 tonnes /ha seed yield and Rs. 11520 and 11590/ha gross income. The maximum cash income from fodder + seed was obtained from Swan harvested for fodder after 85 and 100 days (Rs. 18600 and 18980/ha) and PD2LV65 harvested 115 days after planting (Rs 18380/ha). Thus, It was also concluded that it was more economical to cut oats for fodder, 85-15 days after planting and then leave the regrowth for seed at maturity (Table 10b).

Table 10a. Green-fodder yield (tons/ha) and gross income (Rs/ha) from oat cultivars at different cutting stages
Cutting stage ‘Fatua’ ‘S 81’ ‘PD 2 LV 65’ ‘Avon’ ‘Swan’ Mean
Green

Fodder yield

Gross

Income

Green fodder yield Gross income Green fodder yield Gross income Green fodder yield Gross

Income

Green fodder yield Gross income Green fodder yield Gross income
T1 13.61 6600 13.59 6410 13.79 6480 10.66 5190 10.30 4890 12.39 5910
T2 17.02 6980 16.92 6870 20.16 8220 14.35 58.90 16.93 7000 17.08 6990
T3 22.32 7600 23.46 7910 2948 9810 22.22 7330 26.75 9120 24.85 8350
T4 31.38 8640 33.38 9050 37.76 10300 30.35 8170 36.52 9980 33.88 9240
T5 39.51 10120 54.99 13800 58.90 14750 42.23 10680 54.58 13720 50.24 12610
T6 -                      
Mean 20.64 6660 23.73 7340 26.68 8260 19.97 6210 24.18 7450    
LSD (P=0.01) green fodder yield Gross income

Varieties (V) 1.96 0.72

Cutting stages (CS) 1.75 0.62

V x CS interaction 4.81 1.77

Hussain et al (1994)

T1= Cutting for fodder 70 days after planting and then harvested for seed at maturity,

T2= Cutting for fodder 85 days after planting and then harvested for seed at maturity,

T3= Cutting for fodder 100 days after planting and then harvested for seed at maturity,

T4= Cutting for fodder 115 days after planting and then harvested for seed at maturity,

T5= Cutting for fodder at 50 percent flowering stage for fodder.

T6= Cutting for seed at maturity.

 

Table-10b. Seed yield (tonnes/ha), gross income from seed (Rs/ha), and gross income from fodder (F) + Seed (S) (Rs/ha) from oat cultivars under different cutting stages

Cutting stage Fatua S-81 PD2LV65 Avon Swan Mean
Seed yield Gross Incomefrom seed Gross Income from F+S Seed yield Gross Incomefrom seed Gross Income from F+S Seed yield Gross Incomefrom seed Gross Income from F+S Seed yield Gross Income from seed Gross Income from F+S Seed yield Gross Incomefrom seed Gross Income from F+S Seed yield Gross Income Gross Income from F+S
T1 1.18 6740 13340 0.85 4900 11300 1.86 10470 16950 1.71 9710 14900 2.04 11520 16440 1.53 8670 14580
T2 1.43 8050 15020 0.54 3080 9950 1.77 9880 18100 1.52 8580 14470 2.07 11590 18600 1.46 8230 15230
T3 1.47 8380 15970 0.48 2740 10650 1.48 8200 18010 1.24 6950 14290 1.73 9850 18980 1.28 8220 15580
T4 1.16 6700 15360 0.46 2620 11670 1.41 8050 18380 1.01 5690 13870 1.28 7460 17450 1.06 6100 15340
T5     10120     13800     14750     10680     13720     12610
T6 1.37 7880 7880 1.26 7210 7210 2.19 12380 12380 1.32 7660 7660 1.82 10150 11150 1.59 9060 9060
Mean 1.10 6290 12950 0.60 3420 10760 1.45 8010 16430 1.13 6430 12650 1.49 8430 15880      

 

LSD(P=0.01) Seed yield Gross income Gross income

From F+S

Cultivars(C) 0.206 1.18 1.31

Cutting stages(CS) 0.216 1.25 1.31

C x CS interaction 0.500 2.89 3.21

In India, Taneja et al. (1981) found that oats and barley when planted early at the end of October provided one cut for green fodder without much reduction in seed yields from the same crop. The straw yields decreased significantly when one cut was obtained for forage while the seed yields remained unaffected. However, the straw yields of oats in general were higher compared to barley. Net income was invariably higher when the crop was harvested once for fodder.

On the N.S.W. Tablelands, Dann et al. (1977) suggested that the most biologically profitable combination of herbage and grain production would be obtained by delaying grazing until about 4.0 tons of crop dry matter per hectare was available in winter. Subsequently, Dann et al. (1983) recommended that August (rather than earlier) was the best time for grazing oats. Wheeler (1981) suggested that further research was needed to quantify the effects of grazing on grain yield; in particular, if dual-purpose crops are to be used efficiently, farmers need in particular a means of estimating grain yield reductions in relation to duration and time of grazing.

The effect of grazing a winter cereal crop on its subsequent grain yield has been investigated by numerous workers and depends on many factors. Grazing usually incurs a penalty by reducing grain yields, and typically a 20 percent reduction in grain yield can be expected if the crop is grazed once before stem elongation (Anon, 1984). However, experimental results have varied widely, as indicated below.

Within a wide range of different climatic, environmental and agronomic conditions, some investigators have reported that "early" or "moderate" grazing or clipping of oats or other small grain cereals brought about an increase in grain yield or had no significant effect on it (Hubbard and Harper, 1949; Sprague, 1954; Holliday, 1956; Day et al., 1968; Mengersen, 1972; Dann et al., 1977; Skorda, 1977; Cannon et al. 1978; Fitzsimmons, 1978; Bishnoi, 1980; Craig and Potter, 1983; Davidson et al., 1985b; Sharrow and Motazedian, 1987; Winter and Thompson, 1987).

By contrast, grain yields usually decrease in proportion to the lateness, number and severity of the grazing or clipping imposed on the crop (Hubbard and Harper, 1949; Holliday, 1956; Morris and Gardner, 1958; Pumphrey, 1970; Dann, 1971, Dann et al., 1983; Brown, 1975; Skorda, 1977; Fitzsimmons, 1978: Bishnoi, 1980; Dunphy et al., 1982, 1984; Winter and Thompson, 1987).

Removing vegetation by either grazing or clipping has also reduced plant height, number of heads per m2 and straw production (Day et al., 1968, Pumphrey, 1970). Also delaying the time of clipping until late joint stage (Dunphy et al., 1982) gave reduced fertile tiller survival and fewer seeds per head, but had little effect on the average weight per seed. The higher grain yields following a single light to moderate winter grazing may have occurred as a consequence of some or all of the following:

On the other hand, the reduction in grain yield resulting from late spring and/or more severe grazing or cutting in different conditions might presumably be due to one or more of the following:

- Removal of the main stem and primary tiller apices leaving grain yield to be carried on secondary, weaker tillers.

- Reduction in the amount of growth made before flowering during unfavourable climatic

Conditions such as high temperatures and long day lengths, leading to shorter maturity period, and possibly drought stress caused by increasing evapotranspiration rates (Hadjichristodoulou, 1983).

- Reduction in top growth with a consequent adverse effect on root growth (Hadjichristodoulou, 1983; Cook, 1971) and increased incidence of root rot (Winter and Thompson, 1987).

- Increased risk of frost injury if low temperatures prevail immediately after defoliation (Skorda, 1977).

- Reduction in the supply of assimilates from the leaves caused by defoliation which may bring about a severe reduction of growth in the upper spike lets, increasing the proportion of shrivelled grain (Scott and Biscoe, 1980, unpublished report).

In addition, the type of season may affect the grazing-grain relationship. Grazing has been reported to reduce grain yield more seriously in a dry cold season than a wet mild one (Dann, 1981).

Sprague (1953) reported in a 4-year study with dairy cows that rye, wheat, and oats yielded forage in approximately a 3, 2, 1, relationship. Autumn and spring pasture production from rye was about 75 percent that from a Kentucky bluegrass white clover pasture on the same land from May to October. Grain production increased by autumn grazing and decreased by spring grazing. This increase was much more pronounced in seasons of cool temperature and adequate rainfall than during seasons which were hot and dry. Straw yields were much less after spring grazing but were unaffected by autumn grazing. No lodging occurred following spring grazing and less than 5 percent of the grains were lodged on plots autumn-grazed.

There are many reports in the literature on the influence of temperature and management on yield of forage plants including small grains. Holt (1961) found that frequent clipping resulted in reduced plant development and reduced forage yields. A period of at least 4 to 6 weeks between clippings is necessary for recovery and regrowth. Height of clipping influences total plant development and rapidity of recovery following clipping, but not total yield of harvested forage. Weight losses in the crown area following mild defoliation generally are greater than with more severe defoliation, but recovery is more rapid.

Klebesadel and Smith (1960) harvested oats at four stages of maturity and reported greater dry matter yields from a single harvest in the late milk to mature stages than from 2 to 3 harvests made earlier. Crowder et al. (1955) showed that winter forage yield of oats, ryegrass, and crimson clover was significantly related to the number of hours per growth period with temperatures above 450 F; and yields increased as the interval between clippings increased.

Hadjichristodoulou (1976) reported that under moisture stress conditions, before and during the harvesting period, dry matter yields did not increase significantly with age. Protein content of cereals under low rainfall conditions was higher than that of cereals grown in the U.K. under higher N fertilization levels. Rainfall conditions affected drastically the performance of both cereals and legumes. However average yields were satisfactory.

7.8. Forage /hay yield:

Evaluation and selection of high fodder yielding, good quality and disease resistant oats varieties is important to meet the fodder requirements of livestock. Keeping in view the importance of oats as a fodder crop and the need of farmers, research work on the evaluation and selection of multi-cut, and high fodder yielding cultivars was conducted on farmers’ fields in the Northern Areas during 1996-97. The results are presented in Table 11.

 

Table 11. Green and dry matter yields (tons/ha) of oats and barley cultivars in 1996-97
Cultivars

Sites

Gilgit

Chilas

Ghizer

Skardu

Forage yield Dry yield Forage yield Dry yield Forage yield Dry yield Forage yield Dry yield
S-81

90

24

100

27

86

21

79

19

Scot

82

20

85

21

74

18

70

17

Cuscade

74

18

78

19

65

16

58

14

Swan

68

16

72

17

60

14

55

13

PD2LV65

60

13

63

15

55

12

44

10

Average

74.8

18.2

79.6

19.8

68

16.2

61.2

14.6

Barley

55

11

56

9

40

7

36

6

Dost (1997)

A dual-purpose crop may offer an even more economically attractive option, to harvest fodder in the first cutting or have grazing and then grain also from the same crop. Some results achieved in N.S.W. (Anon. 1984) suggest that cutting oats for hay could be more profitable than harvesting the grain. In all three years of the experiments, considerably more hay than grain was available (in 1979 the crop produced seven times as much hay as grain), yet the grain commonly has only about twice the value of hay. On this basis, nitrogen application after grazing, while perhaps giving an uneconomic boost to grain yield, is economical for hay production – in effect, doubling the herbage yield at flowering. In Cyprus, Skorda (1977) showed that the combined dry matter production from winter grazing and hay at the milk stage was similar to that of hay alone from unclipped cereals. However, Hadjichristodoulou (1983), also in Cyprus, indicated a significant reduction in hay production of different barley varieties following one clipping at the tillering stage.

Dhumale and Mishra (1979) concluded that fresh fodder yields were positively correlated with plant height, flag leaf and tillers/plant. Plant height had a direct effect on yield and all characters except tillers/plant contributed to yield via the plant height. Granier and Razafindrasita (1970) recorded higher fodder yields in Madagascar where oats was tried as a catch crop after rice. On fertile soil early sown oats yielded up to 52 tons fresh herbage/ha. Chaudhary and Mukhtar (1985) concluded that high green fodder yields in oats were attributed to plant characters, viz., more plant height, leaf area and stem thickness, etc. Gill et al. (1977) demonstrated that cultivar ‘EC 13594’ out-yielded the standard cultivar ‘Kent’. Toxler et al. (1980) reported that oats (cultivar ‘Borrus’) when grown as a fodder catch crop yielded 26 percent and 60 percent more dry matter than all the cultivars in the trial, when grown alone and in a mixture, respectively. Solanki (1977) reported that the new cultivar ‘HFO-114’ significantly outperformed, both in green fodder and dry matter yields and in single as well as multi-cut trials, the control cultivars ‘Weston -11’ and ‘Fos-1/29’.

Hussain et al. (1993) evaluated 15 oat cultivars for forage yield, dry matter yield, crude protein, and crude fibre contents at NARC, Islamabad during 1985 -1986 (Table 12). It was observed that cultivar No. 725 produced taller plants, a greater number of tillers per plant, more leaves/leaf area, highest forage yield, dry matter tonnage, and superior forage quality as compared to all other cultivars included in the trial.

Table 12. Green fodder yield (GY), dry matter yield (DY), crude protein contents (CP), crude fibre contents (CF) of different oat cultivars.
Cultivars GY DY CP CF
S 81 75.06 abed 8.98 ed 10.94 def 22.85 e
PD2-LV65 82.83 a 12.08 a 10.06 ghi 23.21 cd
Avon 68.67 cde 9.26 cd 9.65 I 22.48 f
PD2-LV65 x Fulgrain 72.84 bcde 11.01 abc 11.06 cd 23.14 d
Avon x Early Miller 64.82 e 8.40 d 10.40 efgh 22.85 e
No. 707 67.44 de 9.67 cd 10.09 ghi 22.59 f
No. 616 66,98 de 9.77 cd 10.99 de 23.29 bc
No. 656 70.97 cde 9.53 cd 12.44 a 23.33 abc
No. 632 71.98 cde 9.44 cd 10.57 defg 22.79 e
No. 725 81.32 ab 11.84 ab 11.66 bc 22.32 g
No. 677 77.02 abc 10.83 abc 10.09 ghi 23.37ab
No. 668 71.76 cde 10.36 abcd 9.80 hi 22.31 g
No. 681 71.45 cde 9.41 cd 12.24 ab 23.42 a
SS-1 71.30 cde 9.83 bcd 10.21 ghi 22.57 f
S-141 71.14 cde 10.68 abc 10.33 fgh 22.81 e
LSD (0.01) 8.55 2.05 0.62 0.13
Means followed by the same letters do not differ significantly at 1% probability level.

Hussain et al (1993)

7.9. National uniform oats forage yield trials:

Based on the forage yield evaluation and performance data of 400 oats cultivars from USA, Canada, Australia, and New Zealand, the 20 promising cultivars were simultaneously multiplied and evaluated across a range of altitudes/ ecologies during the 1980s, from the sea level to above 2,000m under a series of on-farm, farmer-managed and research station trials, plots and socio-economic surveys. Forage scientists from the National Agricultural Research Centre (NARC), Islamabad, and Fodder Research Institute Sargodha supervised these trials. Representative examples of data generated from these trials-dairy pockets are given below (data were obtained from the National Fodder Research Programme, NARC, Islamabad, "National Uniform Fodder Yield Trials" on oats cultivars at various locations during 1989-2000). The performance of the cultivars included in the trials is given in Tables 13, 14, 15, and 16.

The green fodder and dry matter (hay) produced from these cultivars were usually chopped by manual choppers and fed mixed with other crop residues such as dried sorghum, maize, and millet stover or wheat straw. Resulting animal wastes mixed with bedding were returned to the land as farmyard manure according to established farmer practices/customs. The chemical fertilizer treatment was 40-60-0 N PK kg/ha. There were large differences between the overall performances of cultivars at all the locations under trial suggesting significant differences in agro-ecological adaptation. It also clearly indicated the importance of National Uniform Yield Trials conducted throughout Pakistan to evaluate all the newly introduced oats varieties for selection of promising ones suited to different areas with diverse agro-ecological conditions. All the newly introduced oats varieties were evaluated along with the standard control varieties (Tables 13, 14, 15 and 16). It was interesting to note that due to genotype x environment interaction, all the oat varieties performed differently at various locations of the trials and it was not possible to recommend any single variety across the locations. It should also be noted that the National Uniform Yield Trials is a continuous on-farm evaluation programme carried out by the National Coordinated Fodder Programme NARC, Islamabad and every year all the new introductions are included in these trials. Through this process promising varieties are evaluated and selected that are suitable for various regions with diverse agro-ecological conditions throughout Pakistan.

Table 13. Green fodder yield of oat cultivars at various locations
C.No. Cultivars NARC Islamabad Green Fodder Yield (t/ha)
ARI

Tarnab

ARI

Sariab

ARI Tandojam AARI Faisalabad
1 Coolabah

42.56

29.19

47.30

20.18

88.26

2 Murray

36.94

27.78

51.50

22.22

89.50

3 Nile

33.51

30.09

45.32

17.22

90.44

4 Avon

40.41

27.32

46.35

22.58

94.44

5 Marloo

34.65

31.48

46.45

20.46

96.91

6 Hay

34.24

25.93

54.60

18.88

89.81

7 Wallaroo

31.22

33.33

44.29

23.51

79.01

8 PD2LV65

35.56

35.18

76.22

20.46

79.19

Table 14. Average green forage yield of oats cultivars at various locations in 1998- 99
C.No. Cultivar NARC, Islamabad ARI, Tarnab AARI, Faisalabad ARI, Sariab ARI, Tandojam
1 Wallaroo 74.13 97.6 57.40 17.68 30.81
2 Avon 76.91 103.2 57.86 13.88 28.07
3 Jasper 90.84 122.6 82.86 30.09 24.40
4 Valley 84.95 111.9 64.80 28.24 26.54
5 Marloo 68.57 105.9 74.06 12.96 31.42
6 No. 646 84.32 132.7 82.86 18.51 29.90
7 Reil 91.86 122.1 56.01 20.83 32.95
8 Coolabaah 90.94 120.3 66.19 14.81 21.96
9 Nile 80.62 108.7 60.18 17.12 28.07
10 Ozark 85.12 111.5 66.19 12.96 22.57
11 Murrey 72.90 44.8 57.85 12.96 26.85
12 Foot Hill 80.51 88.3 60.63 17.59 38.44
13 No. 97081 91.50 125.8 77.30 21.29 30.21
14 Saia 88.12 101.3 56.47 24.07 20.44
15 Scott 80.60 101.8 68.05 21.30 31.73
16 Steel 81.33 99.0 72.68 23.12 1966
17 Hay 88.13 116.6 68.51 27.31 21.66
18 Hakae 75.60 100.8 62.02 18.51 25.32
19 Hakae 78.90 110.5 70.36 19.90 33.56
20 PD2–LV 65 75.96 120.3 81.74 22.22 32.03

 

 

Table 15 . Average green forage yield of oats cultivars at various locations during 1999-2000
C.No. Cultivar 1 2 3 4 5
1 Saia 37.04 66.36 36.43 98.00 39.81
2 No.646 38.89 69.45 34.77 103.00 41.66
3 Valley 33.33 61.11 36.34 100.00 41.66
4 Nile 38.42 69.45 52.99 110.00 46.29
5 Steel 34.26 73.46 00.00 98.00 46.29
6 Foot Hill 38.42 70.68 62.83 109.00 50.92
7 Jasper 38.89 71.61 59.61 97.00 46.29
8 Marloo 35.18 52.78 42.04 94.00 50.92
9 Murray 36.11 66.05 39.74 98.00 46.29
10 Hakae 42.13 54.01 49.68 93.00 60.18
11 No 663 60.18 78.40 46.27 91.00 48.14
12 Sargodha 99 52.77 63.00 43.05 104.00 49.07
13 Winjarde 36.57 67.90 77.87 75.00 51.85
14 Superlate 47.22 68.83 49.68 105.00 49.99
15 Local Sargodha 49.09 68.21 57.96 101.00 46.29
16 Local Sheikhupura 45.83 71.00 51.33 80.00 41.66
17 PD2LV65 48.61 62.00 79.48 86.00 44.44
1. National Agricultural Research Centre, Islamabad

2. Fodder Research Institute, Sargodha

3. Agricultural Research Institute, Tarnab, Peshawar

4. NWFP Agricultural University, Peshawar

5. Agricultural Research Institute, Tandojam

Table 16. Green fodder yield of oats cultivars at various locations during 1999
Cultivar Green Fodder Yield (t/ha)
NARC, Islamabad ARI, Tandojam ARI, Tarnab AARI Faisalabad ARI Sariab
Swan 71.77 39.62 20.18 43.00 43.00
Super late 88.42 37.77 22.70 47.00 47.00
Jasper 80.65 37.77 17.03 42.33 42.33
OA330-60 95.46 35.92 19.62 48.67 48.67
Scot 96.19 38.88 24.44 54.33 54.33
Cuscade 93.24 32.22 23.51 51.33 51.33
Tibor 89.91 38.70 22.59 41.00 41.00
PD2-LV65 85.09 37.96 24.40 48.33 48.33

Berdahl and Harvey (1980) evaluated twenty five barley (Hordeum vulgare and Hordeum distichum L.) and twenty five oat (Avena sativa L.) genotypes with a wide range of genetic diversity on summer fallowed and stubble land for 3 years. It was concluded that genotype x cropping practice interaction for yield was not significant for either barley or oats. Exclusive use of summer fallow land in performance testing of barley and oats would not preclude identification of high yielding genotypes for stubble cropping. Barley genotypes that were not high yielding on both cropping practices were found not to have been consistently high yielding across environments in regional cooperative tests.

7.10. Date of sowing:

Supply of fodder mainly depends on the time of planting. The majority of farmers usually try to cultivate forage crops as early as possible to ensure early fodder availability for livestock. In underdeveloped countries where fodder is very scarce, the time of fodder availability during deficit or lean periods is more important than the total quantity of fodder available. The recommended planting season for forage oats in the plains areas of Pakistan is from October 15 to November 15. However, variations in planting dates depend on particular needs of the farmers for their livestock, size and composition of herd, size of land holdings, time of rainfall, availability of fallow land and irrigation water. In order to assess suitable time for maximum forage yields and time of forage availability, sowing date trials on high fodder yielding oats cultivar Scot were conducted at different research institutes throughout the country under various environments. The results obtained are presented in Table 17.

 

Table 17. Green fodder yield of oats cv. Scot under various sowing dates at different locations during 1999

Sowing date

Green Fodder Yield (t/ha)

NARC, Islamabad

ARI, Tandojam

ARI, Sariab

20-9-1995

78.08

55.35

26.66

05-10-1995

76.85

53.39

27.33

20-10-1995

87.34

66.97

35.33

05-11-1995

54.32

54.93

36.66

20-11-1995

49.38

43.51

38.33

05-12-1995

41.66

57.09

32.00

Both at NARC, Islamabad and ARI, Tandojam, Sind, the October 20 planting date, and at ARI, Sariab, November 20 planting date, provided maximum forage yields during December-January, the fodder deficit periods throughout Pakistan. The September planted crop also provided acceptable yields during the month of November at all the trial sites. Although at this time, late planted maize, millet, and sorghum crops produce surplus quantities of fodder, it is very fibrous and low in quality as compared to the green oat forage. The sowing date trials clearly indicated that time of fodder availability is directly correlated with the planting time and some management factors like holding size, moisture availability, genetic potential of crop etc.

Smith (1975) found that high herbage concentrations of in vitro digestible dry matter (IVDDM) and total non-structural carbohydrates (TNC) generally resulted when cool temperature (21/150 C) prevailed after initial panicle emergence, whereas high crude protein (CP) and elemental concentrations generally resulted when hot temperatures (32/260 C) prevailed after initial panicle emergence. In general, yields (g/pot) of dry matter (DM), in vitro digestible dry matter (IVDDM), total non-structural carbohydrates (TNC), crude protein (CP), and fat and ash were influenced more by temperature before than after initial panicle emergence. However, yields of DM, IVDDM, and TNC were reduced markedly by the change from cool temperature (21/150 C) to warm temperature (27/210 C) to hot temperature (32/260 C) and were increased by the change from hot temperature to cool temperature.

Several investigators (Wiggans 1956; Stoskopf et al. 1966) have shown that the herbage and grain yields of spring oats (Avena sativa L.) are reduced when late planting delays the later growth stages to the higher temperatures of summer. The temperature has been shown to influence dry matter yields and growth rates (Wiggans 1956; Stoskopf et al. 1966; Fulton and Findlay; 1966; Fulton 1968; Smith 1975). Fulton and Findlay (1966) found that N, P, and K percentages in oat straw and grain generally were increased by growth at increased air temperatures.

Spring oat (Avena sativa L.) is a cool season crop that can be severely damaged by high temperatures during grain filling (Wiggans 1956; Coffman and Frey, 1961). Colville and Frey (1987) observed that genotypic differences occurred for plant height, grain yield, and test weight for most genotypes but the differences were not associated with maturity differences. Significant variation occurred across sowing dates for plant height, grain yield, and test weight for most genotypes.

Coffman (1954) stated that oats are very responsive to temperature during plant development. Taylor (1967) defined five stages of oat development as being germination, initiation of tillers, initiation of floral primordia, anthesis, and grain fill. He found that anthesis was generally the stage most affected by high temperature. Taylor (1967) and Taylor and Frey (1972) found that duration from germination to any other stage of development depended primarily on temperature effects on growth rate. However, interactions between temperature, genotype, and growth stage occurred.

Heat unit summation studies on oats (Coffman and Frey, 1961) have shown that associations occur between growing season temperature and grain yield, and between temperature and optimal time for sowing. Wiggans (1956) observed that oats planted after early May in Iowa required fewer heat units to reach maturity than did that sown earlier.

The problem of providing feed to livestock in winter, because of the low temperatures that limit pasture growth in temperate areas, has been the focus and main interest of many investigators. Studies reported in the literature include:

Farmers in high rainfall areas in Australia plant dual-purpose cereals as early in autumn as rainfall permits, so that plants are able to grow through a greater part of the vegetative phase in moderate temperature before winter reduces the growth rate. This will build up some bulk in the crop for grazing and give a useful winter feed resource. Fitzsimmons (1978) stated that for N.S.W, time of sowing should be one to three months earlier than for crops sown for grain only, so the plants will be well advanced before the onset of winter. Early sowing which may extend from late February to early May, allows strategic grazing of the crop, thus avoiding grain reduction from lodging (Mengersen, (1972). In addition, early sown crops in Tasmania may be less affected by barley yellow Dwarf Virus disease (Tilt, 1966), although early sowings may catch autumn aphid flights and have more infection than crops sown in May-June under management for only grain yield only (Mendham, personal communication).

On the other hand, autumn sown dual-purpose cereals are usually subjected to periods of water logging, cold conditions and frost during the winter months, and cultivars must be able to withstand the damaged conditions (Russel, personal communications). Gardner (1986) recommended the use of an appropriate cultivar, which enables earlier sowing. This would be of a prostrate growth habit and later in maturity. It should remain vegetative during the winter but should be rapid in its period of jointing (stem elongation) which should take place after the risk of water logging has passed, and hence will be of a later maturity. Moreover, early sowing, by allowing a longer duration of the tillering phase, gives the crop a better opportunity to compensate for missing plants by tillering where the crop has been drilled unevenly or where large gaps in the rows exist. Fund (1974), cited by Garcia del Moral et al. (1984) stated that it is not easy to deduce what may cause the effects because both temperature and day length vary with the sowing date. Gill et al., (1977) reported that the highest yields were obtained by sowing from mid October to early November. The cultivar x sowing date interaction was significant.

Crowder (1953) found that forage produced by oats sown in August and September could have been grazed in late October while oats sown in October would not have furnished grazing until spring. Forage yields were higher following the September planting date as compared to the August planting date. Early sown Victorians oats were severely damaged by Helminthosporium victoriae; however, plant stands of other varieties also were reduced, which indicated that other factors influenced germination and seedling establishment of early sown oats. Autumn and winter oat forage contained from 25 to 30 percent crude protein but the protein content of spring forage dropped to 15 percent. Grain and straw yield were significantly lowered by clipping as compared with no clipping. Clipping after March 1st drastically lowered the grain yields; however, the value of forage obtained should compensate for the loss of grain.

Oats are used more extensively than the other grains in the southeast of USA for winter grazing. Seasonal conditions during and after grazing greatly influence vegetative growth in the autumn and following spring (Burton et al. 1952, Crowder et al. 1953, Hall and Reyes 1944). Subsequent grain yields are also influenced by the intensity of grazing and its duration as shown by Cutler et al. 1949, and Hubbard and Harper (1949) who found that grain yields were correlated with yearly environmental conditions and severity of clipping. Reduction in height of mature plants was correlated with the date at which clipping was terminated in the spring. Clipping to March 25th in Oklahoma reduced yields of certain cereals, exceptions being oats and barley (Finnell 1929, Jones et al. 1944, Staten and Heller, 1946), but Stansel et al. (1937) reported that in Texas oat yields were increased by grazing to March 15th Moderate grazing in the southern wheat belt did not reduce grain yields when conditions were favourable for rank growth (Georgeson et al. 1896, Roener 1943). Washko (1947) stated that grazing small grains with sheep during autumn and spring reduced plant tillering and mature plant height. Grazing also delayed ripening from 4 to 10 days and reduced grain yields 23 to 47 percent.

8. OAT SEED PRODUCTION

The introduction of improved cultivars is one of the quickest methods of improving and enhancing yields of all crops. Soon after identification of potential varieties, seed bulking, its distribution and availability to the common farmers is one of the important steps in the successful cultivation of improved varieties. Unfortunately, unlike grain crops, all improved cultivars of forages are harvested for forage well before seed formation. Also, genetically all the forage cultivars are usually poor seed producers. Therefore, all the efforts of introduction, selection, identification, and cultivation of improved forages would go in vain or be lost if sufficient quantities of seed are not produced and made available to farmers. In Pakistan, most of the seed of improved forage and grain crops is usually multiplied both by private seed companies, Government Research and Extension Centres and to a limited extent by commercial growers. The maximum quantities of improved oats varieties are multiplied by the Fodder Research Programme, NARC, Islamabad (almost sufficient for planting around 500 hectares). The seed thus bulked is sold to farmers, commercial growers, both Government and private dairy farms and other agencies/organizations interested in improved oat fodder production and development. For the last several years, the seed of improved oats cultivars has also been sold to the FAO Afghan Programme for its multiplication and distribution in Afghanistan. The details of total quantities of improved oat cultivars multiplied and sold by Fodder Research Programme, NARC, Islamabad, commercial growers, and other Government and Private seed companies is presented in Table 18.

Table 18. Seed of improved oat cultivars produced (tons) in Pakistan
Year Oats Seed Produced (tons)
1990 5
1991 8
1992 10
1993 12
1994 16
1995 22
1996 27
1997 30
1998 35
1999 43
2000 45
2001 50

Table 18 clearly indicates a steady increase in the production of improved seed and still the demand for improved seed is much higher than the quantities of seed being multiplied by various sources (as with 50 tons of oat seed only about 500 hectares of land can be sown). All the seed of improved varieties of fodder oats produced is used for further increase and distribution/selling to various interested oat fodder growers of the area.

9. CONCLUSIONS

Livestock have always been one of the most important parts of the agricultural system in Pakistan. Lack of quality fodder is one of the major constraints limiting livestock production in the country. At present Pakistan is facing a situation where there is insufficient quantity as well as quality of fodder and consequently many animals are underfed, weak, thin, and therefore, less productive.

There is a considerable need for high quality fodder if better returns are to be obtained from improved animal breeds. Year-round supply of nutritious feed is a prerequisite to improve milk production from stalled cows in the villages and around, as well as in big cities throughout Pakistan. Technical development to improve forage production and supplies could be of immense benefit to the health and prosperity of the people of Pakistan.

Oats has for the last several years proved to be a potential winter forage crop throughout Pakistan, particularly around the big cities and especially in the high altitude temperate northern regions. Cultivation of oats assures production of maximum quantities of early and nutritious forage supplies in the fodder deficit periods during freezing temperatures in the winter season. It is also one of the only major sources of green forage available in winter for the starving cattle. It also helps in the maintenance of body weights, improves the health, and also enhances milk yields of milking cattle which otherwise decline sharply during the winter forage lean periods. It is therefore, safe to claim that the oats crop has brought a winter forage green revolution in Pakistan.

Over the past two decades selected oat cultivars from introduced germplasm have had a significant impact in enhancing livestock feed and hence, on people living in resource poor areas of Pakistan. Fodder oats have helped significantly to alleviate livestock starvation and improve nutrition both of animals and human population. The recent significant impact of new oat cultivars on the availability of livestock feed and therefore, on farmers’ income in resource poor areas of Pakistan, has stimulated the belief that even more can and should be done both to make existing cultivars more widely available through extensive bulking and to introduce new adapted oats cultivars and other improved fodder crop varieties to resource-poor regions through continuous on-farm evaluation with the help and cooperation of the national forage research programme, extension services, private seed companies and NGOs.

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