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The tomato leaf miner, Tuta absoluta (Meyric), second instar larvae were exposed for 1 day to LC 50 of Bacillus thuringiensis (Berliner) subsp. kurstaki or Beauveria bassiana (Balsamo) on treated tomato foliages. Treated larvae had the longest development period while non-treated larvae had the shortest development period. The highest survivorship (l x ) of adults was obtained by the non-treated larvae while the lowest survivorship was obtained by B. thuringiensis-treated larvae. The lowest age-specific fecundity (m x ) of females was obtained by individuals treated as second instar larvae with B. bassiana. The intrinsic rate of increase (r m ) reached its maximum with non-treated individuals while this value decreased to the minimum values with biopesticide-treated individuals. Therefore, development, survival, and reproduction of treated individuals were lower than those of non-treated individuals. The reproduction period and adult longevity were the shortest considering biopesticide-treated individuals. The highest and lowest net reproductive rates (R 0 ) were recorded for nontreated and treated individuals, respectively. The mean generation time was increased with biopesticide-treated individuals.

Background Biological control of insect pests is an economic, eco-friendly and harmless approach to integrated pest management strategies. Bracon hebetor (Say) (Hymenoptera: Braconidae) considers a polyphagous ectoparasitoid of various pests of the order Lepidoptera. The parasitized host insects' defense mechanisms are triggered as a result of the parasitic wasps' injury and penetration. Thus, induce the host cellular and humoral immune responses through a blend of secretions injected into the host body. The present study was designed to evaluate the efficacy of B. hebetor on the immune response of the parasitized full grown larval instar of the rice moth, Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) under natural envenomation. Results On cellular level, the ultrastructure examination of the hemocytes displayed a considerable structural deformation in hemocyte morphology of the detected types of the hemocytes. Moreover, the effects of parasitism on both differential hemocyte counts (DHCs) and total hemocyte counts (THCs) were investigated. The number of prohemocytes (PR) (40.33 ± 5.61, 43 ± 8.33 and 26 ± 2.31) was statistically differed after (24, 48 and 72 h) of parasitism, respectively, compared to unparasitized (31.33 ± 6.49) larvae. Similar observations were recorded in plasmatocytes (PL) before and after the parasitism. However, Spherulocytes (SP) and Oenocytoids (OE) were recorded in the hemolymph with little abundance. On the other side, the quantitative analysis of total hemolymph proteins (THP) provoked a significant effect of considering parasitized and non-parasitized larvae. As the Phenoloxidase (PO) cascade plays a critical role in immune defenses, so the substantial activation of PO in the host's hemolymph following successive hours of parasitism compared to unparasitized larvae using L-DOPA as a substrate indicated the induction of larval immune system. The parasitized larvae showed a gradual increase in the PO activity (0.442 ± 0.103) after 24 h reached up to (1.482 ± 0.272) at the end of parasitism (72 h) in comparable to unparasitized larvae (0.177 ± 0.0.044). Conclusion The present investigations clarified the efficacy of B. hebetor parasitism on the host immune mechanism, which will enable the progress of sustainable stored product protection approaches for the control of an important pest rice moth C. cephalonica.