Rural Industries Research & Development Corporation

The New Rural Industries
A handbook for Farmers and Investors

Adzuki bean

Introduction

Adzuki bean (Vigna angularis (Willd.) Ohwi and Ohashi) is an important, traditional pulse crop in eastern Asia. The grain resembles mung beans, but has a maroon seedcoat and is usually slightly larger. Major consumers include Japan, China and South Korea. The seed is used in many different ways in these Asian countries, but the most common is highly sweetened bean paste with a range of different flavours and textures, as well as sweet soups and desserts. Bean paste is made into a large range of cakes, buns, confectionery, ice blocks and drinks.

Good opportunities exist for export of grain from Australia, particularly to Japan, where many of these products are considered luxuries, which is reflected in the high prices paid for best quality grain. Japan imposes import quotas on grain each year, based primarily on its domestic production, and this leads to some market volatility. Value adding through paste manufacture in Australia would lead to more stable returns to growers.

Adzuki bean is grown in summer in Australia. It is considered more difficult to produce high yielding crops of good quality adzuki bean than of mung bean or soybean. Growers need skills in irrigation, weed and insect management to get the best results.

Marketing issues

Most grain is traded through grain dealers who may issue contracts and supply seed. Harvested grain has to be stringently graded to produce a uniform and attractive sample, especially if it is intended for export. The major part of the Japanese market is for `Erimo' type, represented in Australia by the varieties Bloodwood and Erimo. A small, niche market exists for the larger `Dainagon' type, with seed of this variety now available in Australia.

Production in Australia in recent years has been influenced by price projections, with approximately 1500 t produced in 1994, 500 t in 1995, and 1500 t in 1996. Estimated production for 1997 is 2000 t.

Japanese buyers of `Erimo' type adzuki beans look for large seed (12-14 g/100 seed) with red rather than deep maroon colour and uniform size and shape. In recent seasons, prices received by Australian producers for high quality, graded grain have ranged from $A750 to $A1500/t. `Dainagon' grain must be larger (>16 g/100 seed) and is usually a darker colour than `Erimo' type. Little `Dainagon' has been traded to date, so price trends are unknown, although expectations are for prices higher than `Erimo' type where a market exists.

Japanese imports for quota grain come mostly from China for grain of lower quality, and from the USA, Australia and Argentina. Seasonality is an advantage to Australia over northern hemisphere product, as freshness is a positive quality factor. There are currently no import quotas on adzuki paste into Japan, which makes value adding in Australia more attractive.

Production requirements

Adzuki beans are a summer crop and are considered more demanding than some other pulse crops, such as mung bean or soybean. Trials in Victoria, Tasmania and South Australia have produced only poor crops. Successful crops have been produced in many areas in NSW and Queensland (Fig. 1), using techniques that have evolved over time and are specific to the special requirements of each environment. Good yields of
2.5-3.0 t/ha have been achieved, with most growers able to harvest 1.5-2.0 t/ha. In irrigation areas the recipe for success involves selection of well-drained soils and frequent irrigation to alleviate moisture stress. Adzuki bean prefers milder summer temperatures and higher humidity, and under those conditions, such as are found in northern coastal areas of NSW, it will produce high yields and tolerate waterlogging better than in inland irrigation areas. Quality appears to be higher where pods can develop under milder temperatures, achieved by sowing later in summer (January) or growing in more elevated areas, such as the NSW Northern Tablelands. Excessive summer heat can result in poor quality (small and dark-coloured seed) and in yield loss from a condition called `Gummy pod'.

Varieties

Adzuki cultivation in Australia in recent times started in the early 1970s, with the introduction and testing of a northern Japanese variety by Dalgety Australia. This later became known as `Dalgety' line and met with limited success. Starting in the mid 1970s in coastal northern NSW, a research and development program by NSW Agriculture lead to the release in 1980 of the variety Bloodwood which eventually replaced `Dalgety'. Bloodwood was derived from the old Japanese variety Hikari, grown on Hokkaido where nearly all adzuki beans are grown in Japan. These two varieties, and varieties released more recently in Australia, exhibit similar adaptation to Bloodwood, in that they are mildly sensitive to short days, with rate of development determined mostly by accumulated temperature (heat sums).

Erimo is the most widely grown variety in Hokkaido and was released in Australia in 1997. It is similar in yield to Bloodwood in areas suited to growing adzuki beans and tends to be slightly shorter. Seed size is on average a little larger in Erimo.

Dainagon was released in 1997 to cater for the very limited market in Japan for adzuki beans with larger seeds.

Agronomy

Publications containing detailed information on growing adzuki beans in Australia are listed in `Key references'.

Adzuki beans are more often grown using narrow row spacings (15-30 cm), at high plant densities—500,000 to 600,000 plants/ha. However, wider row spacing with inter-row cultivation has produced good results, particularly in Queensland. The optimum sowing time in NSW and southern Queensland is from mid November to mid December. In coastal NSW, sowing in January will often result in better quality grain than from earlier sowing times, although yields may be lower. In Central Queensland, February sowings are preferred to avoid the heat of midsummer. The growing period, from sowing to harvesting, can be from 80 days in northern areas to 120 days in central NSW.

Irrigation management is critical to success with adzuki beans in inland irrigation areas. Even one short stress period can result in uneven ripening and reduced yields, and in fall in grain quality. Irrigation intervals need to be short, as little as 5 days, which places increased time demands on the grower. Low tolerance to waterlogging means adzuki beans should be grown only on better drained soils.

Pest and diseases

Adzuki beans are slow growing in the first few weeks and can be swamped by faster growing weeds if these are not controlled. Herbicides to control most broadleaf and grass weeds are readily available.

Many types of insect pest will attack adzuki beans and can cause serious losses. These range from leaf and pod-eating caterpillars such as Heliothis, Lucerne Seed Web Moth and Bean Podborer to pod-sucking species such as Green Vegetable Bug, as well as thrips, aphis, bean fly and mites. Crops must be inspected regularly and appropriate control measures taken. Growers need to budget on at least two insecticide applications and up to four applications in some seasons.

Diseases have not been a major problem in commercial crops to date, with only isolated instances of Sclerotinia and Powdery Mildew. Severe heatwave conditions in 1997 resulted in a condition known as Gummy Pod in crops in central NSW, with a sharp yield reduction in some crops.

Harvesting

Under the right conditions, adzuki crops will mature over a relatively short period, with rapid leaf loss and quick seed moisture decline. However, indeterminacy can be a problem in crops maturing in warmer weather, in crops where yield is poor and in sections of a crop where watering has been uneven or moisture stress has occurred at some stage during pod-fill. This is seen as secondary flowering flushes and green patches in an otherwise mature crop. Desiccation can be a useful harvesting aid, but must be applied only when leaf drop has started, as seed damage can occur if applied earlier.

The crop can be harvested with conventional headers, but care must be taken to ensure seed cracking is kept to a minimum and no soil particles are included with the grain. Rotary headers generally do a better job of harvesting a high quality sample.

Japanese buyers look for a uniform sample with large seed (12-16 g/100 seed) and bright colour (more red than maroon). Grain will need to be rigorously graded to ensure uniformity and freedom from extraneous matter such as soil, other plant matter, cracked or damaged seed and other species such as soybean or mung bean. Selecting pure planting seed and paddocks unlikely to have carryovers from previous crops helps freedom from these species.

Most adzuki grain is traded through merchants, who will usually arrange grading and marketing.

Economics of production

The profitability or attractiveness of adzuki bean production depends on the locality where they are grown and the range of alternative crops available. In an economic analysis across current production areas (J. Page, pers. comm.), adzuki beans were not as profitable as cotton, lucerne or peanuts in Queensland areas where these crops could be grown. In coastal NSW, the adzuki beans were more profitable than soybeans, the only comparable crop.

In the Forbes district, where most adzuki beans are currently produced, other crops gave lower returns (see Table 1 - not available in this html version) based on 1996 figures, although adzuki beans are used as a useful rotation with lucerne.

Key contacts

Key References

Desborough, P.J. and Redden, R. 1996. Adzuki beans—R&D for grain export and local processing. Proceedings of the First Australian New Crops Conference, Gatton, 1996.

Falconer, G. and Desborough, P.J. 1994. Growing adzuki beans. Agnote DPI/113, NSW Agriculture.

Wood, P. and Falconer, G. 1997. Growing guide for azuki in Australia. (in press).

Lumpkin, T.A. and McClary, D.C. 1994. Azuki bean: botany, production and uses. CAB International, Wallingford, Oxfordshire, U.K.

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