EFFICACY OF SOYBEAN AND CASTOR OILS IN THE CONTROL OF CALLOSOBRUCHUS-MACULATUS (F) AND CALLOSOBRUCHUS-PHASEOLI (GYLLENHAL) IN STORED CHICKPEAS (CICER-ARIETINUM L)

Refined soybean and crude castor oils were evaluated for the control o f infestations of Callosbruchus maculatus (F.) and Callosbruchus phase oli (Gyllenhal) in stored chick-pea (Cicer arietinum L.). Both oils we re used at 0,5 and 10 ml/kg of seeds. Oviposition, adult emergence and development from egg to adult emergence were evaluated after storing the treated seeds for up to 5 months. At the end of the storage period the effect of the treatments on flavour, consumer acceptability and s eed germination mere evaluated. Both oils inhibited population growth of the two insect species as compared to untreated seeds. Castor oil w as more effective than soybean oil. Castor oil at 5 and 10 ml/kg prote cted stored chick-peas from infestation by C. maculatus for 60 and 150 d, and from infestation by C. phaseoli for 60 and 90 d, respectively. Soybean oil was not an effective protectant, but did reduce the C. ma culatus and C. phaseoli population development for approximately 60 d at 5 ml/kg and for 90 d at 10 ml/kg. No harmful effect was observed on the germination of oil-treated seeds. The oil treatments conferred of f-flavours to the chick-peas, and product acceptability was compromise d by treatment with castor oil and soybean oil at 10 ml/kg.