Chapter IX - FODDER OATS IN JAPAN

Masaaki Katsura

SUMMARY

Oats for fodder were grown on over 8 000 ha in Japan in 2000. Oats are now grown for fodder rather than grain, and the main cultivation area of fodder oats has shifted from Hokkaido to Kyushu. Oats are recognized as an important fodder crop for early winter and spring. The system adopted in the warm region of Japan has oats sown in late summer and harvested for silage or hay in December or later. Seven forage-type cultivars have been released in the past twenty years, and the breeding programme now aims to develop varieties for summer sowing.

Introduction

Oats are grown as a forage crop all over

Japan, from Hokkaido to Kyushu, and used as grain, green fodder, silage and green manure. The cultivation of oats in Japan began in 1872, when oat seeds were introduced from the USA by hand of Kaitakushi, the Colonial Bureau in Hokkaido. As oats are suited to cool temperatures and adequate moisture, they are well adapted to the climate of Hokkaido, but not much grown because of poor demand for oats for feed. Cultivated species in Japan are Avena sativa L. and A. strigosa Schreb. The sown area was about 973 ha in 1894. After that, the livestock industry expanded and keeping of horses and cows increased. Oats were also excellent feed for riding horses, so demand for oats increased gradually and the area expanded every year, reaching 144 300 ha in 1942. After the Second World War, the area fell as there was little demand for horse feed. The increase in sown pasture in Hokkaido and imported concentrates accelerated the decline in cultivation of oats for grain. The area of oats sown for grain in 2000 was 844 ha.

Oats for fodder and silage were rare before the Second World War. In the 1960s, great importance was attached to growing forages in association with the promotion of livestock raising, and many types of forage were grown all over Japan. Oats for fodder and silage attracted attention because of their rapid growth, high yield, palatability and excellent composition, and were grown as winter forage in warmer regions, mostly in Kyushu. The area of oats for fodder and silage reached 31 400 ha in 1969, but has since declined as the area sown to Italian ryegrass (Lolium multiflorum Lam.) has expanded. The area of oats for green fodder and silage in 2000 was 8 060 ha. The transition and distribution of fodder oats in Japan are shown in Figure 9.1 and Table 9.1. Locations and their climatic conditions for some areas where oats have been much cultivated are shown in Figures 9.2 and 9.3.

Oats for grain

The general cultivation pattern in Hokkaido is that oats are sown in late April to May and harvested in August (Tannno et al., 1982, 1983; Yoshihira et al., 1994). The yield per ha is about two tonnes. Characteristics required of cultivars for grain are excellent disease resistance and resistance to lodging. Such cultivars have been introduced from abroad and developed in Hokkaido. In Kyushu, in general, oats are sown in October to November and harvested in the following spring.

Figure 9.1
Changes in fodder oat area in Japan
Source: Statistics on Crops, and Statistics on Cultivated Land and Planted Area, Statistics Department, Ministry of Agriculture, Forestry and Fisheries of Japan.

Figure 9.2
Locations where oats were formerly widely cultivated in Japan

Figures 9.3a, b, c and d
Climatic conditions for four areas in Japan where oats are cultivated.
The left axis shows temperature (°C) and the right axis shows precipitation (mm).
The black circles, diamonds and triangles are monthly average temperature, monthly maximum temperature and monthly minimum temperature, respectively. The bar graph shows monthly total precipitation.
Source: Japan Meteorological Agency.

TABLE 9.1
Distribution and area (ha) of cultivation of grain and fodder oats in Japan for three years

Source: Statistics on Crops, and Statistics on Cultivated Land and Planted Area, Statistics Department, Ministry of Agriculture, Forestry and Fisheries of Japan.

Cultivation for green fodder and silage

There are three cultivation patterns for green fodder and silage in Japan, but, in warm regions, oats sown in late summer and harvested as silage or hay in December or later is now the main cultivation system.

Spring-sown oats

In Hokkaido summer oats are grown as for grain and harvest is after mid-July (Iwasaki et al., 1978; Tobino et al., 1976). This system is not so common in the southwest warm region where cultivars with a spring habit are sown in February or March, and harvested as whole-crop silage in May or June. To harvest as hay after the rainy season, the sowing date can be modified.

Autumn-sown oats

Oats are sown in autumn in southwestern Japan and harvested in spring (Miaki and Nose 1967; Taji, 1966; Taji et al., 1977; Ueda and Kakihara, 1988). Some mow oats twice, cutting luxuriant oats in early spring as green feed and next harvest regrowth for green feed, silage, hay or allowing growth to proceed for grain production (Nishimura et al., 1955, 1960b; Nishimura and Saito, 1958, 1960). In Kyushu, early maturing cultivars are sown from late October to early November; heading starts in April and they reach milky to dough stage in May, which is the time for harvest as silage (Hosoya et al., 1988; Nishida and Nakano, 1979). Cultivars suited to autumn sowing vary from very early to medium or late maturing ones. Farmers can select a suitable variety according to their production systems.

Summer-sown oats

This topic was reviewed in Katsura (1999).

The main forages in Japan are summer crops such as maize and sorghum, which are sown in spring and harvested in summer and autumn (Table 9.2). Farmers try to get high yield with high nutritive value. Some farmers try to grow maize twice in a year; as the interval between the first harvest and second seeding is very short, farmers are very busy. In the warm region, maize tends to be sown early to avoid damage by typhoons in late summer, while rice is often transplanted in early spring and also harvested in summer. Therefore, crops following maize or rice are necessary for efficient utilization of fields where arable land is scarce. Oats are an important crop for producing feed in early winter and next spring, along with Italian ryegrass. In the case of summersown oats, harvested in early winter, farmers have enough time to prepare for sowing the following crops. To save labour and avoid risk, summer-sown oats are an important alternative. In addition, the weather from autumn to early winter is mild in southwest Japan, particularly in southern Kyushu, i.e. Miyazaki and Kagoshima (Figure 9.2). Enough rain and warmth are easily assured in autumn in these regions. Therefore, this cultivation type is considered to be preferable to make the best use of the climatic conditions.

Summer sowing is not favourable for oats, which is a long-day plant. High temperatures persist until mid-September, which corresponds to the germination stage. Daylength shifts from long to short and temperature from high to low (Figures 9.3a-d). These conditions influence panicle emergence and subsequent growth. Consequently, it is important for farmers to select a variety suitable for summer growing. Oats sown in summer are generally harvested as silage (Ohta et al., 1995) (Figure 9.4), but some farmers harvest it as hay for producing calves; the crop is frosted in December to January to reduce moisture. Small-scale farmers producing calves sometimes use local oat varieties, which they maintain (Figure 9.5) (Harada et al., 2002; Hayashi and Yawata, 1956; Taji and Akiyoshi, 1966). These are usually grown in small fields and mown in small quantities daily and fed with rice straw. Oat straw is also used as feed (Figure 9.5).

Although the above cropping pattern is pure-crop oats, mixed crops with legumes such as vetch had been used for autumn-sown crops (Hiraishi et al., 1954; Nishimura et al., 1953, 1955b, 1960a, c, d). Now mixed sowing of oats with Italian ryegrass is often used (Kakihara and Fukuda, 1990). They are sown in September or October and harvested twice in winter when the ratio of oats is high, and in the following spring, when only the Italian ryegrass survives. Because of their excellent early growth, oats are often used as a nurse crop or companion crop (Iwasaki et al., 1978; Tabata et al., 1992).

A

B

C

D

Figure 9.4
The harvest of oats as silage for dairy cattle in summer-sown cultivation.
A. Japanese cv. Haeibuki bred for summer cultivation. B. Oats are cut by a mower or a mower conditioner. C. They are turned by tedder and raked once or twice daily for a few days to reduce moisture to 60-70 percent. D. They are chopped finely and transferred for storage in a bunker silo

Breeding fodder oats

Oat breeding began in the Meiji era, in the late nineteenth century, for grain in Hokkaido. The objectives were to increase grain yield with early heading and to strengthen lodging resistance, cold resistance and disease resistance. Breeding oats for grain stopped in 1994 because of their decreasing cultivation, as mentioned earlier. Breeding oats for forage began in Hokkaido as the use of oats changed from grain to forage. Since the main area of forage oats has shifted from Hokkaido to Kyushu, breeding of oats for forage started in 1988 in Kyushu.

A

B

C

Figure 9.5
Use of oats derived from seeds being maintained by farmers.
A. Farmers mow oats in small lots daily. B. After threshing, the oat straw is fed to beef cattle. C. Seed being maintained by a farmer, from material inherited from his parents.

Oat cultivation is now mostly for green fodder and silage; this is expected to continue. The breeding of forage oats for summer-sown cultivation has been intensive for the past twenty years. The cultivars for summer-sown cultivation have been primarily introduced from the United States of America and from Australia. As they were not bred to grow in the summer in Japan, it has been necessary to develop some suitable cultivars locally. The focus has been on early heading in autumn, resistance to crown rust (Puccinia coronata Corda) and lodging resistance. Those characteristics are very important to obtain oats of high quality. As a result of this work, cultivars Haeibuki and Tachiibuki have been released, which have superior qualities under Japanese condition, especially in lodging resistance.

TABLE 9.2
Sowing and harvest seasons of major fodders in Japan.

Oat cultivars developed in Japan since 1980 are listed below.

Akiyutaka is the first variety for forage and green manure developed at the Hokkaido National Agricultural Experiment Station, in 1980 (Tabata and Kumagai, 1985). It is well adapted for autumn-sown fodder in southern Japan.

Hidaka, bred at the Hokkaido National Agricultural Experiment Station in 1990, is a highly lodging-resistant and high-yielding variety for grain (Tabata et al., 1994). It is adapted to all Hokkaido.

Akiwase, developed at the Hokkaido National Agricultural Experiment Station in 1989, is extremely early maturing, suitable for summer sowing, with good lodging resistance (Tabata et al., 1992).

Super Hayate Hayabusa, developed by the Snow Brand Seed Co. in 1992, is an extremely early maturing and high-yielding variety for summer and autumn sowing; not suitable for grain production.

Haeibuki, bred for silage or green fodder at Kyushu National Agricultural Experiment Station in 1996 (Ueyama et al., 2001) is an extremely early maturing cultivar suitable for summer sowing. Summer-sown Haeibuki heads before Akiwase.

Kanmuri, developed at the Hokkaido National Agricultural Experiment Station in 1995, is highly resistant to crown rust in Yamaguchi, Miyazaki and Okinawa prefectures. It is recommended for areas where crown rust is prevalent in southern Japan, such as Chugoku, Kyushu and Okinawa districts, mainly for autumn sowing (Takada et al., 1999).

Tachiibuki, bred for silage or green fodder at Kyushu National Agricultural Experiment Station in 2000, is an extremely early cultivar suitable for summer sowing. Its lodging resistance is much greater than Super Hayate Hayabusa and Haeibuki in summer- and autumnsown cultivation.

Prospects

Breeding oats for grain in Hokkaido stopped in 1994 and the area of oats for grain remains small. Grain production, except for very early or early maturing cultivars, is difficult in Kyushu because of the rainy season in June and July, when medium or late maturing oats mature. Growing oats for forage, both summersown and autumn-sown, in the warm region does not compete with growing summer crops such as maize and paddy rice. It is easy to rotate summer crops and oats in fields. There is much arable land where farmers grow nothing after harvesting the summer crops, potentially allowing oats to be grown in the break.

In Japan, self-sufficiency in food was 40 percent on a calorie basis in 2001. Raising this figure has become an important element in Japanese agricultural policy. It is necessary to improve the selfsufficiency in feed because Japan imports most feed and self-sufficiency in feed was only 25 percent in 2001. Large quantities of oat grain and hay are imported from Australia, the USA, Canada, etc. The quantity of imported feed shows no tendency to reduce, and there are problems in management of livestock because farmers are dependent on overseas supplies, the organic matter cycle is unbalanced, pollution builds up, and so on.

Although the area of oats for feed has been decreasing in Japan, the demand for feed oats is very high. Oats are an important forage for increasing feed auto-sufficiency. Cultivars with excellent resistance to lodging and disease have been developed recently, with another due to be released soon. They are very important for production of high quality forage, and such cultivars will contribute to improved self-sufficiency in feed in Japan.