Vigna aconitifolia (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Vigna aconitifolia (Jacq.) Maréchal

Protologue: Bull. Jard. Bot. Nat. Belg. 39: 160 (1969).

Family: Leguminosae

Chromosome number: 2n= 22

Synonyms

Phaseolus aconitifoliusJacq. (1768).

Vernacular names

Moth bean (En); haricot papillon (Fr); Malaysia: mittikelu; Thailand: matpe.

Origin and geographic distribution

Moth bean is a native of India, Pakistan and Burma, where it grows both wild and cultivated. It is also grown in China, Sri Lanka, Africa, USA and Thailand.

Uses

Green pods and ripe, whole or split, seeds are eaten cooked. In India and the USA moth bean is also grown for green manure, forage and hay and as cover crop. Seeds are used medicinally in diets for fevers; roots are said to be narcotic.

Production and international trade

Recent data are not available. It is estimated that 1.8 million ha are under this crop. In 1974 India was the largest producer of moth beans with 500 000 t; Thailand is the leading exporter with 30 000-40 000 t/year.

Properties

Per 100 g edible portion, mature seed contains: water 10.8 g, protein 23.6 g, fat 1.1 g, carbohydrates 56.5 g, fibre 4.5 g, ash 3.5 g. Seed weight is 1 g/100 seeds.

Botany

Annual herb with short, erect stem, 10-40 cm long, with many prostrate branches of 30-150 cm length. Leaves alternate, trifoliolate; leaflets up to 5-lobed, 5-12 cm long, lobes narrow, acuminate. Flowers about 9 mm long, yellow, several together in axillary, capitate racemes, with 5-10 cm long peduncles. Pods subcylindrical, 2.5-5 cm x 0.5 cm, covered with short, brown hairs, 4-9 seeded. Seeds rectangular to cylindrical, 3-5 mm x 1.5-2.5 mm, light brown, whitish green or yellow brown, rarely mottled. Germination is epigeal. Vegetative development starts slowly. Maturity ca. 90 days after sowing, early types mature in 75 days.

Ecology

In India moth bean is grown from sea level to 1300 m. It requires uniform high temperatures and grows best with a soil temperature of 27^°C. It is drought resistant and does well with a well distributed rainfall of 500-750 mm/year. It grows on many soil types, but is particularly suitable for dry, light sandy soils, and is an important crop of arid to semi-arid regions in India. It is a quantitative short-day plant.

Propagation

is by seed. Seeds should be sown on a well prepared seedbed. Moth bean is usually sown broadcast, requiring 10-15 kg/ha when grown as a sole crop. When grown for forage seed rate is 7-34 kg/ha. Sown in rows 75-90 cm apart at a depth of 2.5-4 cm, seed rate is 3.5-4.5 kg/ha for pure stands. In many areas, as in the Indian arid belt, moth bean is interplanted with cereals like pearl millet and sorghum or rotated as a green manure crop with cotton. It is grown as an irrigated but mostly as a rainfed crop. Moth bean is notable for its pest and disease resistance, but it is susceptible to yellow mosaic virus, nematodes and leaf spot diseases. It is also parasitized byStrigaspp. Bean weevil can attack the seed during storage. Plants can be harvested ca. 90 days after sowing. They are difficult to harvest with a mower because of the prostrate branches. The plants are usually cut with a sickle, left to dry for one week, then threshed and winnowed. Seed yields are in India 200-1 500 kg/ha, in USA 1 240-1 800 kg/ha. Grown for forage yield is 37-50 t/ha for the green matter produced, giving 7.5-10 t/ha hay.

=== Genetic resources

and breeding ===

Low production is due to a lack of high yielding cultivars. Germplasm collection is urgently needed. The ecological limits and the optimal cultivation methods should be investigated. === Breeding ===

should concentrate on the production of completely erect cultivars.

Prospects

Lack of information on its potential and cultivation is limiting moth bean's spread and utilization. Because of its drought resistance it can substantially increase the food and forage production in (semi-) arid conditions, and protect the soil against erosion when other vegetation dies.

Literature

[1] Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York and London. p. 286-288. [2] Mathur, J.R. & Sharma, R.C., 1980. Problems and prospects of moth bean (Vigna aconitifolia (Jacq.) Maréchal) in arid and semi-arid zones of Rajasthan. In: Arid zone research and development. Scientific Publishers. Jodhpur, India. 531 pp.

Authors

C.C.C.M. van Oers