A laboratory assay was designed to determine the insecticidal efficacy of Beauveria bassiana (Balsamo) Vuillemin (Hyphomycetes: Moniliales) and diatomaceous earth (Diafil 610) against Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae). The fungus B. bassiana was applied at 2.23×10 7 , 2.23× 10 8 and 2.23×10 9 conidia kg −1 of wheat individually as well as mixed with 200 and 400 ppm of Diafil 610. The conditions for the trials were 30±2 o C with 55% r. h. and the counts for mortality were made after 8, 16 and 24 d. All the dead adults were removed after each count and the vials were kept for the next 60 d to assess the emergence of the F 1 generation. The findings from these studies proved that the extended exposure interval and the highest combined dose rate of the entomopathogenic fungus and the diatomaceous earth gave the maximum mortality of the beetles. The emergence of the progeny was also highly suppressed where the maximum dose rate of the synergized treatments was applied. The rate of mycosis and sporulation in the cadavers of R. dominica was maximum where the low dose rates of B. bassiana were applied.

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The pod borer Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is an important insect pest of chickpea and several other crops in Asia, Africa and Australia. The present studies were carried out on integration of various practices for the management of H. armigera in Punjab, Pakistan, during 2004-05. Chickpea variety 'CM-2000' was selected for evaluating various strategies such as cultural, mechanical, biological, microbial, and chemical control, individually and in various possible combinations, for the management of H. armigera at three different locations. Integration of weeding, hand picking and indoxacarb (an oxadiazine insecticide) proved to be the most effective in reducing the larval population and pod infestation and resulted in the maximum grain yield. The larval population of the combined effect of these practices was not significantly different from hand picking + indoxacarb, weeding + indoxacarb, and indoxacarb alone. Hand picking in combination with Bacillus thuringiensis, and weeding+hand picking, also controlled the larval population significantly, but was inferior to the above treatments. The release of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) did not control H. armigera. It was concluded on the basis of the cost -benefit ratio that hand picking was the most costeffective method for the control of H. armigera, while the maximum increase in grain yield was obtained in plots with weeding, hand picking, and indoxacarb.