Pests and Diseases

The rice bean is remarkably resistant to most insect pests and diseases. The seeds are resistant to Bruchids, which generally damage the other pulses during storage (Chandel, et al 1978). The following fungi cause diseases in rice bean: Corticium solani, Myrothecium roridum, and Wororinella umbilicata (Duke, 1981).

In the Philippines, powdery mildew and rust occur sparingly. Cucumber mosaic virus also attacks the plant. Root knot nematodes, including Heterodera glycines and Meloidogyne javanica infect rice beans (Duke, 1981). Since the plant has been used traditionally as a post-rice crop, nematodes were no major problem due to the flooding of the rice fields but the promotion of the rice bean in non-rice areas could endanger the status of the plant as a "pest free crop".

Evaluations conducted by Gurmel S. Sandhu, G.S. Bassi and M.S. Sohoo (1987) on susceptibility in seeds of the rice bean to the pulse beetle (Callosobruchus maculatus) shows larval death during penetration was observed both in decorticated and undecorticated seeds. Rice bean was comparatively resistant to the attack of cowpea virus, cowpea leaf miner (Acrocercopes sp.), Distantasca terminalis and cowpea semilooper (Plusia orichalcea) on different dates of sowing (Dhaliwal and Tiwana, 1988).

Seeds of the rice bean are free from the attack of pulse beetle (Callosobruchus chinesis L.) even under controlled artificial infestation (Chatterjee and Dana, 1977). However, the crop was attacked by pod-boring wevil (Apion clavis Gerst).

Weeds do not have a significant influence on the grain yield of rice bean. This is attributed to the smothering effects of the well-developed canopy on the weeds (Kar, B.C., et. al. 1993).