Radiant SC12% (Spinetoram) is a new generation of spinosyn group. Effect of this bio-insecticide against larvae of Spodoptera littoralis (Boisd) was studied to evaluate the susceptibility of 2 nd and 4 th larval instars in laboratory. The LC 50 of radiant was 0.05 and 0.03 ppm. After 24 and 48 hours, respectively for the 2 nd larval instars. Where the LC 50 were 6.67 and 2.86 ppm after 24 and 48 hours, respectively for the 4 th larval instars. In the semi-field experiment, recommended doses of radiant exhibited high mortality 100 & 95.7 % after 0 and 1 days, respectively then decreased gradually to reach 58.1 % after 7 days. Also the field experiment showed high mortality 91.4% after 2 days then reduced gradually to reach 83.1% after 8 days. The effect of different concentrations in laboratory and recommended doses in field showed 100% mortality of entire hatched egg masses. Effect of recommended doses of radiant against predators inhabiting cotton field demonstrated that radiant was safe to natural enemies. The effect of LC 50 of radiant on the major biochemical component of 4 nd larval instars after 24 hours showed that, the amount of total carbohydrates, total proteins, carbohydrate hydrolyzing enzymes (invertase, trehalase and amylase), and acid & alkaline phosphates were significantly decreased. Where the acetylcholinstrase activity was significantly increased.

During the period from February 2009 to September 2010, a mosquito (Diptera: Culicidae) survey was conducted in Jazan province the southwestern Region of Saudi Arabia,. A total of 29414 larval and 484 adult mosquitoes were collected from 41 sites, resembling 10 governorates. The collected mosquitoes related to 7 genera and 16 species. The genera were Aedes (A.) (1 species), Stegomyia (St.) (1 species), Aedimorphus (Am.) (1 species), Anopheles (An.) (4 species), Lutzia (L.) (1 species), Culex (Cx.) (7 species), and Culliseta (Cs.) (1species) and the mosquitoes species encountered were A. caspius Pallas, St. aegypti Linnaeus, Am. vexans arabiensis Patton, An. d'thali Patton, An. pretoriensis Theobald, An. Arabiensis Patton, An. turkhudi Liston, L. (Metalutzia) tigripes de Grandpre & de Charmoy, Cx. sitiens Wiedmann, Cx. decens Theobald, Cx. bitaeniorhynchus Giles, Cx. pipiens Linnaeus, Cx. quinquefasciatus Say, Cx. sinaiticus Kirkpatrick, Cx. tritaeniorhynchus Giles, and Cs. longiareolata Macquart. Cx. pipiens is the most prevalent species in Jazan region. It was encountered in 90 % of total collection sites. Cx. tritaeniorhynchus is less prevalent encountering in 80 % of total collection sites but An. Arabinesis was encountered in 70 % of total collection sites. St. aegypti, L. (Metalutzia) tigripes and Cx. sitiens were encountered in 50% of total collection sites. Cx. quinquefascitus, Am. vexans and Cs. longiareolata were encountered in 40 %, 30% and 20% of total collection, sites respectively. An. pretariensis, An. d'thuli, An. turkdi, Cx. decens, A. caspius and Cx. bitaeniorhynchus were the least prevalent mosquitoes in Jazan region encountered in only 10% of total collection sites. Am. vexans was the most abundant 57 % (17121), Culicine spp. 38.2 % (11416) , Anopheline spp. 1.5 % (433), St. aegypti 3 % (749) and each of Aedine, Lutzia and Culleseta were encountered less than 1%.

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Effectiveness of commercial formulations of Bacillus thuringiensis var Kurstaki "Agerin, Dipel 2X and Dipel DF" on total protein and lipid contents were studied. Activities of detoxification and metabolic enzymes were also measured in treated and control larvae of cotton leafworm Spodoptera littoralis. Collected samples from treated larvae at intervals of 48 and 120 hrs post treatment were analyzed to assess the total protein and lipid contents as well as the enzymes activities. Significant reductions were observed in total protein content at 120 hrs larvae in all treatments compared with control. In all larvae treated with Agerin and Dipel DF the lipid content was significantly elevated after 48 and 120 hrs of treatment while Dipel 2X showed no significant difference in lipid content. However, fluctuated changes in the enzymes activity of treated larvae were found. We conclude that there are differences in biochemical effects between various commercial formulations of Bacillus thuringiensis kurstaki. In most cases Agerin was found more effective on S. littoralis than others.

The susceptibility to IGRs, moulting hormone agonist, mimic (tebufenozide) and chitin synthesis inhibitors match (lufenuron) was studied in the 2 nd and 4 th larval instars of the cotton leafworm Spodoptera littoralis (Bosid). Obtained results revealed that match was the more toxic against 2 nd larval instars at sub-lethal concentrations LC 25 and LC 50 (0.3 and 0.6 ppm, respectively) than mimic (1.1 and 1.5ppm, respectively). But LC 90 level was the same in the two IGRs. With respect to 4 th larval instar, match induced the higher toxic effect at all sub lethal doses than mimic. Biochemical analysis showed that match and mimic exhibited a severe reduction in the activities of the detoxification enzymes, acid phosphatase and esterases (α and β), as compared to the control. The enzymatic activities were inhibited with the increase in the time posttreatment and also with the increase in dose. Therefore, the tested IGRs, tebufenozide and lufenuron , may be not detoxify by these enzymes.