Twenty-two strains of entomopathogenic fungi were tested in the laboratory to determine their pathogenicity to adult Megalurothrips sjostedti. All the fungal strains were pathogenic to the insect. Beauveria bassiana and Meturhizium anisopliae strains caused mortality ranging between 29 and 100% and 54 to loo%, respectively. In contrast, Verticillium lecanii and Paecilomyces furnosoroseus were less virulent, causing mortality ranging between 29 to 68 and 13%, respectively. The LT5, of the most virulent B. bussiana and M . anisopliae strains was 2.7 and 2.4 days, respectively. The LC5, for the most active B. bassiana strain was 7.9 x lo6 conidia/ml. The LCsO for the most active strain of M . anisopliae was 1.3 x lo6 conidia/ml. Two strains of B. bassiana and four strains of M . anisopliae were found to be highly pathogenic to M . sjostedti, which suggests a potential for their use in the biological control of the pest.

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Ten varieties of cowpea grains were infested with Callosobruchus maculatus. This was to determine the level of quality deterioration of the cowpea varieties caused to the grains by the insects. The insect census taken at one, two and three months showed a progressive increase in insect population from one month to three months. The quality deterioration was determined by proximate analysis of the grains at one, two and three months. The percentage total protein determined by the estimation of total nitrogen content, showed an increase from one month to three months. The total protein in the control experiment showed a progressive decrease with increase in storage period. The percentage ash in the control was higher than the infested, and it decreased with storage period. The percentage fat decreased with infestation. The control had a higher percentage fat than the infested, but the fat decreased with storage period. The percentage fibre was higher in the infested grains than the control, and it increased with infestation period. The percentage carbohydrate decreased with infestation. The control samples had higher carbohydrate than the infested ones. The percentage carbohydrate however, decreased with increase in storage period. There was a significant difference (p 4 0.05) in the insect population amongst the different cowpea varieties.

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