EFFICACY OF JOJOBA OIL AGAINST TWO STORED LEGUME SEED INSECT PESTS Callosobruchus Maculatus (F.) AND C. Chinensis (L.)

Adults of Callosobruchus maculatus (F.) and C. chinensis  (L.)  were exposed to broad been seeds treated with four different concentrations of jojoba oil (70 % EC) 875, 1750, 3500, 7000 ppm and untreated control to evaluate the effectiveness of jojoba oil as a protectant. A negative correlations were observed between the jojoba oil concentration and all evaluated biological parameters, fecundity, egg viability, developmental period of the immature stages, adult emergence, broad bean seeds viability and seeds weight loss percentage for both tested insects C. maculatus and C. chinensis. The obtained results cleared that C. chinensis was more susceptible to jojoba oil than C. maculatus andthere is a significant difference between the two tested insects in all tested biological aspects regardless to the concentration (for the fecundity 168.33 and 190 eggs/female, hatchability percentage 60.33 and 69.5 %, developmental period 26.3 and 28.3 days, and 36.33 and 45.33 F₁ emerged adults and weight loss percentage 6.02 and 7.56%, respectively. The highest concentration 7000 ppm gave a complete protection of seeds with zero weight loss percent for both tested insects. The mean percentage of weight loss in untreated seeds was 16.04, 12.96%, for C. maculatus and C. chinensis respectively, while, weight loss% reduced to more than the half averaged 7.56 and 6.02% for treated seeds. The residual effect of jojoba oil treatments was clearly effective in the first month of storage period which gave a 100% protection of treated bean seeds with 0.0 F₁ emerged adults in both tested insects (100% mortality of developmental stages). After six months of storage period, residual effect of jojoba oil reduced by the storage period prolongation, While, jojoba oil still could protect the broad bean seeds against C. maculatus and C. chinensis attacks although the efficacy of jojoba oil decreased with aging 79.92 and 61.86% reduction of F₁ adult emergence compared to untreated control. Slight harmful effect of jojoba oil application on the viability of broad bean seeds, so reduction of germination was most appeared at, the highest concentration7000 ppm particularly
at the end of storage period averaged 28.22%.