Effects of sublethal exposure to abamectin on the biological performance of Neoseiulus longispinosus (Evans) were studied under ambient laboratory conditions of 28 +/- 2 degrees C and 80 +/- 15% RH with 24 h light. The red form of the twospotted spider mite, Tetranychus urticae Koch, complex (Acari: Tetranychidae), was offered as prey. The LC50 obtained from the contact bioassay at 48 h after treatment was 0.015 ppm (AI). A big change in kill for a given variation in dosage for the regression slope probably indicated that abamectin was unlikely selective. Sublethal exposure to abamectin caused a reduction in survival with the female reaching 50% mortality by the sixth day and the male 4 d later. The mean preoviposition period was extended by almost 1 d, whereas the mean oviposition period was shortened by almost 5 d causing a reduction in the mean fecundity female-1 to almost half that of the untreated females. The net reproductive rate (Ro), the intrinsic rate of increase (rm), and the finite rate of increase (lambda) of the treated females were markedly inferior. Treated males were seriously affected; the mean life span was almost half that of the untreated.

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Eight isolates of entomopathogenic fungi were evaluated as dried conidia against the rice moth, Corcyra cephalonica. In bioassays two isolates of Beauveria bassiana (BbGc and BbPs) and one isolate of Metarhizium anisopliae (MaPs) consistently gave high mortality to C. cephalonica larvae. Formulations in either kaolin, talc or tapioca flour (20 % w/w a.i.) thoroughly mixed with long grain rice in plastic cups (8 cm diameter by 5 cm) gave complete larval mortality by the 12 th day of treatment. However, in general those formulated in kaolin and talc were more efficacious and faster to kill compared to those formulated in tapioca flour or the unformulated control. Even at the lowest rate of 0.05 g BbGc in kaolin provided 100% mortality 7 days after introduction compared with other dust formulations. Isolate BbGc in kaolin and talc administered at 0.4 g a.i. in 200 g rice packed in plastic kept at room temperature provided protection against the rice moth up to 4 months of storage. Larval mortality in excess of 90% was obtained 15 days after introduction. Formulations of MaPs was effective only within the first month of storage beyond which infectivity rapidly declined.

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