Chapter IV - FODDER OATS: AN OVERVIEW FOR SOUTH AMERICA

Luiz Carlos Federizzi and Claudio Mario Mundstock

SUMMARY

Oats were introduced to Latin America by the Spanish soon after the discovery of the continent; they are used as grain for the milling industries and as horse feed, and also as a cover crop in notill planting systems, as a fodder for animal grazing, and for forage and silage. Oats are grown in five major environments in South America: (1) the temperate area of Argentina and Uruguay; (2) the temperate area of Chile; (3) the subtropical area of Brazil (south of 24°S); (4) the tropical area of Brazil (north of 24°S); and (5) the tropical high altitude area (Andean region, with parts of the highlands of Bolivia, Ecuador and Peru). These regions differ widely in terms of environment, crop use, major breeding programmes and area under oats. The largest area under oats is in temperate and subtropical regions, but oats as a grain crop are increasing in area and importance in all environments of South America. The cropped area is increasing every year because it is a major component in the rotation system used by farmers when they adopt the no-till system.

Background

There are no historical data, but various oat species were probably brought to the Americas shortly after their discovery by the Spanish, who brought oats to feed their horses. Thus, oats are a comparatively old crop in South America, and Avena byzantina was probably the first introduced in the south of the continent, in Argentina and Uruguay; its area increased at the beginning of the twentieth century, especially in Argentina and Uruguay, where it was used for fodder and for quality grain production (Boerger, 1943: 1043).

The genus Avena is a polyploid series with diploid, tetraploid and hexaploid species, some of which are cultivated, while others are invaders of cultivated fields. In Latin America, all the species were probably introduced from Europe, especially the diploids (A. strigosa) and the hexaploids (A. sativa and A. byzantina), which are cultivated and are very important economically. A. byzantina and A. sativa have been widely intercrossed, and it is difficult to distinguish them in the current varieties, so, in this study, white oats are called A. sativa. A. sterilis is a weed in Argentina and Uruguay. Although oats are best adapted to the temperate environments of the South American continent, they are widely adapted to low latitudes and tropical and subtropical environments.

Oats are important in Argentina, Bolivia, Brazil, Chile, Ecuador, Peru and Uruguay (Table 4.1). In most countries, oats are more important as fodder for livestock in the field. In Brazil, Argentina and Chile, oats are very important as grain for the transforming industry. These countries grow the largest areas (Table 4.1). The harvested area is quite small in the Andean region, as most of the area sown is used as fodder. Data for Uruguay are the same for the last five years, implying that they are probably out of date.

TABLE 4.1
Mean values (± standard errors) for five years (1998-2002) of oat harvested area, grain yield and total oat yield in the main producing countries in South America

Source: FAOSTAT (www.fao.org - as of 20 February 2003).

Recent studies (Rebuffo, 1997) report that the area under oats in Uruguay was 65 000 ha in 1989, but then declined to approximately 36 000 ha between 1991 and 1995. Grain yields are much higher in Chile, where conditions are more favourable for oats, than in Argentina, Brazil and Uruguay. Yield differences reflect the conditions of each environment, but nevertheless yields in Argentina and Brazil are increasing compared with other countries. In South America, only Chile has been a frequent oat exporter; Argentina was a large exporter of good quality oats, but recently lost much of its market. Brazil was an importer until the end of the 1980s and now produces the oats it needs, but imports in years of poor harvest. Statistical data on crops such as oats, that in the past were less important, have to be viewed with caution, bearing in mind the great difficulty in data collection in the countries of the region.

Oats are grown in subtropical environments at the time of year when temperatures are at their lowest. White oats are grown on approximately 200 000 ha. Black oats (A. strigosa), a diploid species, is grown on more than 3 million hectares for soil cover or forage (Figure 4.1).

Figure 4.1
Maize growing through a bed of dessicated black oats (Avena strigosa) straw in southern Brazil

Oats, because of their multiple uses, are a technically and economically viable alternative crop in many production systems in the region. The inclusion of oats in a rotation improves the physical, chemical and biological properties of the soil, reduces diseases and pests in other crops and provides biomass to maintain soil cover for a long time, with great reduction in weeds and soil erosion.

The main area under oats is as a cover crop to protect the soil before spring and summer crops. Black oat is mostly used. In general, no P or K fertilizer is needed and only N is added as a top dressing. White oats are grown when the end use of oats is grain (Figure 4.2), but when the end use is fodder, black oats are sown.

Figure 4.2
A field of white oats (Avena sativa) for grain production in Brazil

Where two crops a year (one in winter and another in the summer) can be grown, oats are becoming an important option for grain because they are used in no-till systems in rotation with wheat and barley before the soybean crop (Figure 4.3). Because of the large amount of biomass in the oat plant, farmers use less herbicide on soybeans (Figure 4.4) if they are preceded by oats, compared with wheat and barley.

The crop succession system in most of the region involves two crops per year (winter and summer). In South Brazil, small grains (winter crops: oats, wheat and barley) are sown from April to June (according to the end use and altitude) and harvested from October to November. When grown as a cover crop, A. strigosa is desiccated in August, at the beginning of flowering. Summer crops are predominantly maize and soybean, sown from September to November. Maize is generally sown in September-October after A. strigosa desiccation, and harvested in April-May. Soybean is sown after the winter cereal harvest, usually in October- November. Some other crops are used, such as black beans and popcorn. Maize, sown early, can be harvested in February- March. In these cases a cover crop can be grown for two to three months, before sowing the winter crop.

D.G. COOPLANTO
Figure 4.3
A no-till system in which soybean is planted after oats have been harvested

Figure 4.4
Soybean growing in a field previously planted with oats in a no-till system

The production system on small farms involves different crops. In tobacco production areas (spring and summer), A. strigosa is used as a cover crop, or as fodder in winter. In fruit producing areas, oats are sown between the lines as a winter cover crop. This permits nitrogen retention and better weed control, decreasing the use of chemicals.

In South Brazil, white oats are sown from the end of May to the beginning of July; they are commonly fertilized with phosphorus, potassium and nitrogen for grain production where soils are deficient in these nutrients. Generally, N is applied at sowing (20 percent) and at the beginning of tillering (80 percent).

Disease control is usual, and one or two fungicide applications are necessary to reduce leaf rust (the main disease) and Pyrenophora avenae (common in no-till systems). Barley yellow dwarf virus (BYDV), Pseudomonas syringae and Ustilago avenae also occur.

Insects damage oats, especially aphids and caterpillars. Among the aphids, Schizaphis graminum can transmit BYDV and others, such as Metopolophium dirhodum and Sitobion avenae, can occur until close to maturity.

Harvest is in October and is frequently damaged by high rainfall and humidity, which delay harvesting and cause losses from lodging and quality reduction (low test weight and increase in grains spotted by fungus).

Oats are used as a high quality grain in human and animal nutrition. A considerable part of the area sown is for autumnwinter grazing and also for hay and silage. As a forage producer, in pure stands or mixtures, oats are the most important crop in the Southern part of South America, because of the high quantity and quality of forage produced in this environment. Also, oats can be used for silage and hay in winter. Oats are used as forage for dairy or beef cattle, and on sheep farms used for grazing or making silage to be fed in combination with soybean meal or maize in winter, when native forages grow slowly. Oats can help stabilize the supply of meat and milk, with lower costs than maize silage or concentrate. Oat grain is harvested in October-November, which is the off-season for maize or soybean (harvested from February to April).

Black oats are grazed in winter under two production systems. In one, common in South Brazil, oats are sown direct into native pasture in autumn (April-May), when the growth of the original pasture is very slow. Fodder is obtained for 3-4 months, until the end of winter and beginning of spring and the re-growth of the native pasture. In the second system, oats are sown in association with ryegrass and clover, forming a typical winter pasture. Sowing is in April-May and the mixture lasts until October-November (end of spring). In both cases, complete soil fertilization is needed.

The use of black oats for grazing and in rotation with other grain crops reflects the need to increase the income of farmers and reduce production costs. It is estimated that, for Rio Grande do Sul state, Brazil, in 2000, about 1 250 000 ha of black oats were grown for fodder (for dairy and beef cattle, and sheep) (Floss, 2001).

The system used on small farms involves growing A. strigosa on small areas and, instead of grazing, the plants are cut (manually or by machine) and used as green fodder.

Fodder oats are sown in autumn (April-May) and are mainly used in June and July. The seed rate is 80 kg ha^-1 (250 seeds m^-2) using no-till machines. In some cases, oats can be sown direct into the native sward without soil preparation. In other cases, oats are sown direct into soybean or maize residues, also without soil cultivation.

Breeding

Oat breeding has been going on for a long time in South America. It started with the first experimental stations in the area, namely the Instituto Nacional de Investigaciones Agropecuarias (INIA) in Uruguay, Instituto Nacional de Tecnología Agropecuaria (INTA) in Argentina, Secretaria de Agricultura do Estado do Rio Grande do Sul, in Brazil, and INIA in Chile (Boerger, 1943; Beratto Medina, 1994; Federizzi et al., 1999). All varieties developed and released in Argentina, Brazil, Chile and Uruguay in the past 25 years are descended from an international programme started in 1974, with a grant from USAID, called Breeding Oat Cultivars Suitable for Production in Developing Countries, organized by H.L. Shands, Professor of Agronomy at the University of Wisconsin at Madison. Since 1977, the Quaker Oats Company has sponsored it, and it is now called the Quaker International Oat Nursery (QION). Currently, professors from the Universities of Minnesota and Florida prepare the nursery, which is composed of around 100 pure lines and 200 F2 or F3, or both, populations from crosses, including varieties from several programmes around the world. Currently, the nursery is sown at thirty locations in North and South America, Africa, the Near East, Europe, Australia and New Zealand. It has been a source of genetic diversity for several oat programmes throughout the world (Forsberg and Shands, 1986; McDaniel, 1997). Currently, six major oat breeding programmes are active in South America, which have contributed new varieties in the recent past. There is also a minor breeding effort by private companies in Argentina and Brazil.

Macro-environments

South America has five major agronomic macro-environments, which differ with respect to crop end use, soil fertility and composition, rainfall, average temperatures, day length, humidity and growing season length. The valleys in the Andes, where oats are mostly used as a forage, is the least typical environment. Chile has the best conditions for grain production, while Argentina and Uruguay are similar and Brazil has two contrasting environments.

Temperate Argentina and Uruguay

There is a large area cropped with oats in both countries, located between latitudes 32° and 36°S. Soils are fertile, rainfall is adequate, temperatures are mild and days are long (spring to summer), providing a long growing season. Forage oats are sown at the beginning of autumn and usually grazed in winter and spring, and then the grain is harvested in summer. When farmers grow oats only for grain, planting is postponed to June-July and harvest is in January. There are several frosts during this season and the late frosts may damage oats. More than 2 million hectares are under oats (mostly in Argentina) and the cropped area is limited, since it has to compete with wheat and barley. The major problems for the crop are stem rust and crown rust. Since 1993, stem rust has been endemic early in the season (May) or in November and December, with severe damage to yield and grain quality.

TABLE 4.2
Effect of cutting frequency on the production of autumn, winter and spring forage, hay yield, grain yield and test weight for three cultivars in Uruguay. Sowing date: 29 March 1995.

Source: Rebuffo, 1997.

The old variety Suregrain, introduced in the 1960s, is the most important for forage in Argentina. It is grown on a very large area of the Argentinean pampas (more than 2 million hectares). Forage cultivars have recently been released, such as Millauquén Inta (1987), Cristal Inta (1990), Bonairense Payé, Máxima Inta, Bonairense Inta Calen and Bonairense Inta Maja (2000). Most cultivars are very similar, but Calen and Maja have very good resistance to stem rust, which has been the most important disease problem in terms of forage; yields are very similar those obtained by Rebuffo (1997) and reported in Table 4.2.

In Argentina, some cultivars are specifically for grain. The more important ones are UFRGS 16, Maja, Calen and Bonairense Payé. UFRGS 16 is a Brazilian cultivar that is resistant to all races of stem rust in the region, and has been grown in Argentina for the last five years, with very good grain and milling yield.

In Uruguay, oats are mainly used for grazing. In the dairying regions they are sown in January and February, but in the beef region oats are sown later (March to May) (Rebuffo, 2001). The period of use is 6 to 9 months, and because of this long cycle, high-biomass-producing varieties should be available. In spring, part of the oats are harvested for hay and silage and 10-25 percent for grain (Rebuffo, 2001). Growth habit and sensitivity to lodging and leaf rust are limiting factors for grain production in most of the cultivars used. The most important variety is 1095a, which is an A. byzantina type released in the 1930s. More recently, two new cultivars have been released: INIA Polaris and INIA Lê Tucana, with better resistance to crown rust and very good yields (Table 4.2).

Data obtained by Rebuffo (1997) (Table 4.2) in Uruguay shows the potential for forage production in different seasons of the year in this environment.

There are three major breeding programmes in the region.

INTA - Barrow Chacara Experimental Station (Argentina)

This is one of the oldest oat breeding programmes in South America, and until 1990 its major goal was to release varieties for forage and then grain harvest. The main objectives are (Wehrhahne and Carbajo, 1997): develop new cultivars with higher yield potential (forage or grain, or both); increase adaptability to different regions; improve grain quality; increase resistance to crown and stem rust; increase tolerance to frost damage; and improve tolerance to aphids. The programme relies on introduction of material from the QION and has recently released two new grain-type cultivars with resistance to stem rust.

INTA - Bordenave Experimental Station (Argentina)

This Station was created in 1927, and the first experiments with oats were reported in 1934. All cultivars released by this programme have been dual-purpose (forage and grain). The most successful variety (Suregrain) was introduced in 1969 and occupied more than 90 percent of the oats area in the 1980s (Tomaso and Bucar, 1994). The main objectives are to improve forage and grain production and increase resistance to crown and stem rust. All cultivars released so far are more suitable for forage production and are susceptible to crown and stem rust.

INIA - La Estanzuela (Uruguay)

This oat breeding programme started very early in the twentieth century. Because, historically, oats have been a multipurpose crop in Uruguay, especially forage production for autumn and winter, most varieties are old and have these characteristics. Recently released cultivars are better grain producers (Rebuffo, 1997). The main objectives are to: develop new cultivars with more forage and grain production; develop cultivars with different morphological characteristics; increase resistance to crown and stem rust; and increase tolerance to BYDV.

Temperate Chile

Chile has an excellent area for small grains, with favourable environment and soils. About 8 percent of the area devoted to grain is under oats, which, in Chile, are grown between latitudes 37° and 43°S, in fertile soils, with mild temperatures and long days, that results in a long, favourable growing season (up to 6 months). Oats can be sown in May or mid-August and harvested in January or February. Because of the low humidity, diseases are not as serious as in other regions of oat production in South America, but crown rust (Figure 4.5) and BYDV are present in most years. Yields are generally high and grain quality and milling yield excellent. In some years, low rainfall in November-December reduces yield and grain quality.

Figure 4.5
Varieties of oats susceptible (in front) and (behind) to crown rust

In Chile, 80 percent of the area under oats is for grain, but only 10 percent of that is used for industrial purposes. The remaining 90 percent is for livestock feed on the farm. In this favourable environment, European varieties were introduced with favourable growth habit, agro-ecological adaptation and high yield potential. Since 1975, new introductions have been made from USA through the QION programme. This newly introduced and adapted germplasm has brought new traits, such as resistance to lodging, good agronomic type and resistance to crown and stem rusts. This combination of traits resulted in high yielding cultivars with good grain quality (Beratto Medina, 1997). Oats are a very important crop, and one that competes for land with barley and wheat, and is used in the rotation to reduce or avoid the root diseases of the other cereals.

There is one major breeding programme: Instituto Nacional de Investigaciones Agropecuarias (INIA), which started in 1965 at the Experimental Station of Carrilanca, with several cultivars released for all the Chilean environments. It focuses on breeding oats with excellent milling yield, and the main cultivars in use by the farmers are Neptuno Inia, Urano Inia and Nehuén. The main objectives are to: introduce and develop oat cultivars with high yield potential; improve the milling yield and chemical composition of oat grain; introduce resistance to major diseases; and improve the agronomic characteristics of the oat plant (agronomic type, resistance to lodging and short plant height).

Subtropical area (south Brazil)

Brazil has two major areas of oat production: subtropical and tropical. In both environments, oats are expanding in area, even when competing with wheat and barley. The southern (subtropical) region is between latitudes 24° and 32°S, with soils of average fertility and high levels of aluminium. Good solar radiation, non-limiting temperatures and adequate rainfall in all months allows intense soil use throughout the year.

The climatic conditions make it possible to grow two crops a year: one in winter (generally a small grain), and a summer crop, typically maize or soybean. In this area, rainfall ranges from 1 100 to 1 500 mm, well distributed throughout the year, humidity is usually very high during most of the season, and in the coldest months days are short and the average temperature varies from 12 to 15°C. The growing season is less than 150 days. The major crop rotation used by most farmers is half soybean and half maize in summer, followed in winter by one-third of the area with wheat, barley or oats, and two-thirds with black oats. The black oats are sown in May and desiccated with herbicide by flowering time (usually in September), when maize is sown. The market prices of wheat, oats and barley will define the area of each crop. Most farmers avoid growing wheat or barley two years in succession because of disease problems, and oats are used in this case. Oats can be a very good alternative crop for poor farmers because it grows and develops well on poor soil and is tolerant of aluminium toxicity. Because of its several uses, in mild winters (when there is enough forage from native species) the oat crop can be allowed to mature and the grain harvested and used for animal feed just when the price of maize is usually high. Farmers growing black oats before soybeans are switching to white oats and use their grain for animal feed on the farm, or sell if prices are favourable.

TABLE 4.3
Grain yields (kg ha^-1) of several oat lines in tropical and subtropical regions of Brazil, with and without fungicides

Notes: * With two application of fungicide tebuconazole (0.75 litre ha^-1) for crown rust control.

Diseases are widespread, especially crown rust, with several different and virulent races occurring most years, and with high probability of rainy days at harvest time. Thus, yields are variable among years and there is a large genotype × year interaction.

Currently, the grain producing cultivars available to farmers are: UPF 15, UPF 16, UPF 18, UPF 19, UPF 20, UPFA 22, UFRGS 14, UFRGS 15, UFRGS 17, UFRGS 19, URS 20, URS 21, URS 22, OR2, OR3, OR4, FAPA 4, FAPA 5, FAPA 6, CFT 1, CFT 2 and IAC 7. Yields obtained in tropical and subtropical areas (average of two sites over five years, 1997 to 2001) from the most important varieties are shown in the Table 4.3, and the major traits in Table 4.4.

Because of crown rust, cultivars have a very short life in the farmer’s fields and new ones need to be released every year. Environmental conditions are ideal for rust spread (high temperature and humidity) and oats are present in fields all year round. The pressure by the fungus is therefore more intense than in any other region of the world (Stuthman and Federizzi, 1997).

TABLE 4.4
Agronomic characteristics of several oat lines currently in use in south Brazil

Key:
-F = without fungicide; +F = with fungicide; S = susceptible; MS = moderately susceptible; R = resistant; MR = moderately resistant.

Two good, important traits present in Brazilian oat cultivars are their ability to provide good grain filling in warm environments, and very good tolerance to high soil aluminium levels (Sanchez- Chacon, Federizzi and Milach, 2000).

The main variety for forage and soil cover for no-till planting is called preta comum, or "common black". It is an old A. strigosa variety selected from an even older one called Saia, introduced to the State of Rio Grande do Sul in the early 1940s and of unknown origin. It is grown on more than 3 million hectares as a cover crop in autumn and winter. New cultivars have been released in more recent years. Cv. São Carlos is an A. strigosa variety better adapted to the tropical region of Brazil. Another A. strigosa - cv. IAPAR 61 - was released in 1993 and quickly became the most popular soil cover variety. It has a long cycle (134 days from emergence to flowering) and some cold requirement for flower initiation, so its flowering is delayed in the more tropical areas. FAPA 2 is another forage variety of A. sativa, with good dry matter production in both oat environments of Brazil.

Data on the production of forage for three cultivars and their main agronomic traits are presented in Tables 4.5 and 4.6.

Data obtained by Floss (2001) over a ten-year period at Passo Fundo (RS) with A. strigosa (average of several genotypes every year) (Table 4.7) shows the usual variation among years normal in the subtropical environment, with years of excellent development and years of poor crop development and growth.

TABLE 4.5
Forage production from three oats (in southern Brazil)

Sources: (1) Scheffer-Basso et al., 2002a. (2) Scheffer-Basso et al., 2002b.

TABLE 4.6
Days to heading, height, 1000-grain weight and reaction to crown and stem rust of three oat varieties at Passo Fundo, Brazil

Key: MS = moderately susceptible; MR = moderately resistant.
Sources: Scheffer-Basso et al., 2002a, b.

TABLE 4.7
Biomass and dry matter yield of A. strigosa at Passo Fundo, Brazil in different years

Source: Floss, 2001.

The popularity of black oats as a winter crop is attributable to a combination of characteristics: low seed price and favourable conditions for seed production; low production cost compared with other green manures; high carbon: nitrogen ratio, ensuring high biomass necessary for the no-till production system (over 6 t ha^-1); hardiness compared with other cereals; better aluminium tolerance; better growth and development in poor soils; a very aggressive root system that helps to improve the physical proprieties of the soil; better tolerance to root diseases than wheat and barley; and better resistance to trampling.

Silage is one way of using white oats (A. sativa), but is not common. Cropping techniques are similar to those adopted for grain cultivation. The most favourable cutting period is flowering; the crop is wilted to eliminate excess water, and high yields of good quality are obtained (Table 4.8) (Sartoretto et al., 2002).

There are two main oat breeding programmes in the region.

TABLE 4.8
Silage dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) acid detergent fibre (ADF) and total digestible nutrients (TDN) for black and white oats, expressed as percentage of DM

University of Passo Fundo - UPF

This programme started in 1977, and is based at the University of Passo Fundo, in the city of Passo Fundo in the State of Rio Grande do Sul. It has been very successful in releasing cultivars with excellent yield potential and grain quality. Initially, the programme relied exclusively on germplasm introduced through the QION, but, in the 1990s, crosses made by the programme were of more importance. There are six cultivars recommended for all oat producing regions. The main objectives of the programme are to: develop cultivars with high yield potential and adaptation to Brazilian environments; create cultivars with better grain quality; increase tolerance to crown and stem rusts; increase resistance to BYDV; and increase tolerance to aluminium.

Federal University of Rio Grande do Sul - UFRGS

The programme at UFRGS started in 1974 and is at the College of Agronomy in Porto Alegre. The primary goals of the University have been to train students in plant breeding (under- and postgraduate levels) and to do basic research on small grains. Because of the needs for new oat varieties, the programme in the 1980s was devoted more to oats than wheat, and now is devoted exclusively to oat breeding. Nine cultivars from the programme are currently being used by farmers. A major characteristic of the programme is its strong support from genetic studies, most of them done by graduate students. The main objectives are to: develop oat germplasm with higher yield and grain quality, and adapted to subtropical conditions; modify the oat plant to become a grain producer (better agronomic type), with short plant height and resistance to lodging; create cultivars with early maturation; increase resistance to crown and stem rusts, using partial resistance to crown rust; increase resistance to leafspot (caused by Pyrenophora avenae; Figure 4.6); and carry out genetic studies on traits of agronomic importance.

Figure 4.6
The leafspot fungus (Pyrenophora avenae) growing out from infected oat grains in culture

Tropical Brazil

The tropical area lies between latitudes 20° and 24°S, at less than 900 m above sea level. It is a new area, where oats are being grown with relative success. Soils are of medium fertility, without aluminium, and temperatures are high and days are shorter, with a growing season of less than 120 days. Yields are variable, with major differences between years. Oats are sown in March and harvested in August, when humidity is low and there is no rain, which provides good conditions for an excellent quality grain harvest. The major problems are crown rust, low rainfall, and frost damage in years of more severe winters. This environment is also covered by the two breeding programmes discussed under subtropical Brazil, and the cultivars used are the same.

Tropical high-altitude area (Andean)

The most tropical area where oats are grown in South America is in valleys in the Andes of Bolivia, Ecuador and Peru. For this environment (tropical high altitude), oats are grown as a dual-purpose crop (both forage and a source of grain for animal feed). Oats in this area are grown at over 2 600 m elevation but very little published information could be found at the time of writing.

In Peru, oats are grown at between latitudes 7° and 8°S, above 2 700 m and with annual precipitation of about 700 mm. Oats are sown for grazing and forage production during October-December. The oat season is very long (up to 7 months) and most cultivars are introductions from Europe. They are very tall, and suitable for forage production. The main cultivars used in the region are Vilcanota, Mantaro and Pastos (A. strigosa).

In Ecuador, oats are grown at elevations of over 2 600 m, mostly for forage. Sowing is in December-January in higher zones, and in February-March at elevations below 2 800 m. The season is very long, taking nearly 200 days to complete full crop maturation, and grain yields can be more than 3 t ha^-1. Oats occupy a small area because they compete for space with wheat and barley. The main problem in this region is stem rust caused by Puccinia graminis f.sp. avenae, especially in the hottest and most humid months close to grain maturation. Another problem is the green cereal aphid (Schizaphis graminum) that transmits BYDV, causing plant yellowing and death.

There are at least two experimental stations selecting lines adapted for this environment.

In Ecuador, the Estación Experimental de Santa Catalina (an INIAP station) has released cultivars INIAP-82 and INIAPMonjarda 90. Both cultivars are adapted to more than 2 500 m elevation and a season longer than 190 days, and provide very good forage production (>30 t ha^-1) and good grain yield (1 500-3 800 kg ha^-1) (Fuentes and Cazar, 1990).

In Peru, the Estación Experimental Bãnos del Inca has been working with oats and has released a variety of A. strigosa named Pastos, introduced from Europe (Hungary and France). Also, there is information that basic seed was been produced for two oat varieties, Vilcanota and Mantaro 15.

Research

Brazil

Most oat research is devoted to grain production, and is carried out by various institutions and involves activities ranging from biotechnology to the development of new cultivars and agronomic practices suited to the various oat-growing environments. More than 100 papers are presented every year at the Brazilian Oat Meeting, and several graduate programme dissertations have been presented that focus on the oat crop. In Brazil, oat research at Universities allows training in formal graduate studies or through short courses or visits.

As far as A. strigosa is concerned there is no true breeding programme in Brazil, and there is a need to start effective breeding in order to obtain better cultivars. The current variety of black oat, used extensively as a forage and cover crop, is very susceptible to crown rust and has been mixed with several other black oat varieties. There is also a need for a better extension programme, since most agronomists working with farmers and cooperatives know little about the crop. In Brazil, grain and animal production are carried out in different regions, and only recently have grain producers begun to integrate on-farm grain production with livestock production. Oats might increase in importance for forage in the grain growing area.

Argentina

Oat research has almost disappeared in Argentina. The very few programmes that were in place did not handle the stem rust epidemic properly at the beginning of the 1980s and no cultivars with good resistance were developed. Only the programme at Barrow is now developing new oat cultivars with resistance to stem rust. Argentina urgently needs to add well-trained young researchers, especially in breeding for forage and grain, and in plant pathology.

Chile

The single oat breeder in Chile is near retirement, and new staff are needed, in view of the national importance of the oat crop.

Regional cooperation

Oat researchers in Argentina, Brazil, Chile and Uruguay are linked through the QION, and also through meetings and frequent visits, so information and breeding material flow freely in the region. For the Andean region, a link is needed between the researchers working there and other breeders in South America, so that they can share experiences and breeding material.