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%.

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.

No abstract

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.

(100,150,200,250 and 300 Gy) and the combined effect of them and essential oil were tested. Results: Comparing the estimated LC10, LC50, LC90 values of present investigation of mentioned essential oils indicated that essential oils of Origanum majorana is more toxic to G. mellonella than the other essential oil of Cymbopogon proximus, then were selected in combined with the dose of 100 Gy in the shared experience. It also found that the percentage of pupation, emergence and sex ratio decreased with increasing concentration of both extracts -The lack of the number of eggs and the percentage of hatched eggs increase with the increase the radiation

The present study aimed to evaluate the biological effect of insect growth regulator flufenoxuron (Cascade) as a chitin synthesis inhibitor against 2 nd and 4 th larval instars of Spodoptera littoralis, to determine its toxicity. Effect of sublethal doses LC 25 , LC 50 and LC 90 were used to investigate the enzymatic activities. The tested IGR significantly increased the larval and pupal durations, on the other hand decrease the percentages of pupation, adult emergency, fecundity and fertility of the eggs produced by the adult progeny. The tested compound significantly induced larval mortalities, which were dose dependant.Treatments of the 2 nd and 4 th larval instars with the tested IGR induced some morphogenic abnormalities in larval, larval-pupal and pupal stages, as well as pupal-adult intermediate. Some emerged adults have various degrees of malformations. All the treated larvae as 2 nd instar showed a high sensitivity to the tested IGRs more than 4 th instars. The treated larvae in both 2 nd and 4 th larval instars with the sublethal doses LC 25 , LC 50 and LC 90 showed a significant decrease in enzyme activities of acid phosphatase and the non-specific esterases, α,β esterases at different times intervals post treatments.

The journal of Toxicology and pest control is one of the series issued twice by the Egyptian Academic Journal of Biological Sciences, and is devoted to publication of original papers related to the interaction between insects and their environment. The goal of the journal is to advance the scientific understanding of mechanisms of toxicity. Emphasis will be placed on toxic effects observed at relevant exposures, which have direct impact on safety evaluation and risk assessment. The journal therefore welcomes papers on biology ranging from molecular and cell biology, biochemistry and physiology to ecology and environment, also systematics, microbiology, toxicology, hydrobiology, radiobiology and biotechnology. www.eajbs.eg.net Provided for non-commercial research and education use. Not for reproduction, distribution or commercial use.In this work we studied the effects of the Beauvaria bassiana and Metarhizium anisoplia on Bracon brevicornis in the laboratory to evaluate the possibility of application of entomopathogenic fungi and the parasitoid Bracon brevicornis side by side in IPM programs. Metarhizium anisoplia was found No mortality observed at the highest concentration (4g/L) and the lowest tested concentration while the recommended concentration recorded mortality (0.1333±0.0908%) of B. brevicornis adult. While The recommended concentration (2g/L) of B. bassiana induced no mortality among the adult parasitoids while its highest tested concentration (4g/L) and the lowest concentration (1g/L) gave mortality (0.0667±.06667%) and (0.1333±0.0908%) respectively.