Phaseolus lunatus L.
Family
Leguminosae
Synonyms
Phaseolus bipunctatus Jacq., Phaseolus limensis Macfad.
Vernacular Names
| Malaysia | Kacang china, kacang jawa, kekara kratok. |
| English | Lima bean, butter bean, Madagascar bean. |
| Indonesia | Java bean, kratok. |
| Philippines | Sibatse simaron, patáni, zabache. |
| Burma (Myanmar) | Burma bean, white Burma. |
| Thailand | Thua rachamat. |
| Vietnam | Dâu ngu. |
| French | Haricot de Lima, pois du Cap, fève créole. |
Geographical Distributions
Phaseolus lunatus has a neotropical origin with at least two centres of domestication: Central America (Mexico, Guatemala) for the small-seeded forms and South America (mainly Peru) for the large-seeded forms. In post-Columbian times, it spread throughout America. Spaniards brought seeds across the Pacific to the Philippines and from there to Asia, mainly Java and Burma, and to Mauritius. The slave trade took them from Brazil to Africa, particularly in the western and central parts. Some large-seeded forms from the Peruvian coast were distributed to south-western Madagascar and southern California. It is now cultivated throughout the warmer parts of the world.
Description
P. lunatus is an annual or occasionally perennial herb, bushy forms that can reach up to 0.6 m tall while 2-4 m tall in climbing forms. The roots are thin or swollen and measure up to 1.5-2 m deep.
The leaves are trifoliolate. The leaflets are ovate, acuminate and measuring 5-19 cm x 3-11 cm.
The inflorescences are axillary racemes, measure up to 15 cm long, with many nodes and flowers. The bracteoles are persistent. The sepal is bell-shaped while the petal is 0.7-1.0 cm wide. The standard is hood-shaped and pale green or violet. The wings are white or violet. The keel is sharply upturned, white or occasionally pigmented. There are 10 stamens, which are diadelphous. The style is coiled with the apical region pubescent. The stigma is ellipsoid and adaxially directed.
The pods are oblong, measuring 5-12 cm x 2.5 cm, generally curved, sometimes with a hook-shaped top and with 2-4-seeded. The seeds are variable in size, shape and colour, kidney-shaped, rhomboid or round. The colour is uniform or speckled or mottled, white, green, yellow, brown, red, black or purple. There are often transverse lines radiate out from the hilum. The seedlings are with epigeal germination where the first leaves are simple and opposite.
Ecology / Cultivation
P. lunatus contains day-neutral genotypes which flower in day lengths of 9-18 hours and short-day types which require critical day length of 11-12.3 hours for flower initiation. The optimum temperatures range from 16 to 27 °C; frost is not tolerated. The normal annual rainfall is 900-1500 mm but the crop tolerates as little as 500-600 mm once established. It is grown in the lowland tropical and subtropical areas but may climb to 2000-2500 m altitudes. It prefers well-aerated and well-drained soils with a pH of 6.0-6.8. However, some cultivars tolerate acid soils with pH as low as 4.4.
Line Drawing / Photograph
References
- Plant Resources of South-East Asia No. 1: Pulses.
