Ain Shams Scholar Collection:
http://hdl.handle.net/123456789/654
2024-03-29T06:37:00ZChanges of cotton leaf worm haemocytes and esterases after exposure to compounds derived from urea and Rice Straw
http://hdl.handle.net/123456789/213990
Title: Changes of cotton leaf worm haemocytes and esterases after exposure to compounds derived from urea and Rice Straw
Authors: Heba A. Hassan; Bakr, Reda; Marah M. Abd El-Bar; Galal A Nawwar; Heba M. Elbanna
Abstract: In the current study, the role of cotton leaf worm haemocytes and esterases in detoxification were recorded. The haemolymph was collected from the 6th instar larvae which treated with LC25, LC50, LC70 of three newly compounds extracted from wastes from natural origin, Cyano acetyl urea (CAU), Benzimidazolyl acetyl urea (BAU) from urea and Cyano acetyl urea (CAH) from rice straw as 4th instar larvae. The mean of total haemocytes counts in haemolymph of untreated 6th larval instar was 9430±35.78 cells/mm3. Data indicated an increase in the total haemocytes of treated ones with CAU, at LC25 and LC50, BAU at LC25 and CAH at LC25, LC50 of CAH the percentages of change were: 19.01, 14.31, 1.90, 21.00 and 14.55, respectively. In addition, the percentages of oenocytoid counts were increased in all concentrations for all compounds except for CAH (at LC70) as it did not change comparing control count. On contrast, data cleared reductions in granulocytes in all concentrations for all compounds except for BAU at LC50 as they increased slightly (15.12%). On the other hand, the results were showed great differences in number of zones of esterase activity and in substrate specificity between treated and untreated samples. For instance, in the case of α - naphthyl acetate, 36 esterase bands were detected in control and treated larval samples with Rf ranging between 0.01 to 0.28. While, in the case of b - naphthyl acetate, 39 esterase bands were detected in control and treated larval samples with Rf ranging between 0.01 to 0.92.2013-12-01T00:00:00ZThe Activity of Some Detoxification Enzymes in Spodoptera Littoralis (Boisd.) Larvae (Lepidoptera – Noctuidae) Treated With Two Different Insect Growth Regulators
http://hdl.handle.net/123456789/213989
Title: The Activity of Some Detoxification Enzymes in Spodoptera Littoralis (Boisd.) Larvae (Lepidoptera – Noctuidae) Treated With Two Different Insect Growth Regulators
Authors: Bakr, Reda; Mona F. Abd Elaziz; Nehad M, El-barky; Mohamed H. Awad; Hisham M. E. Abd El-Halim
Abstract: The susceptibility to IGRs, moulting hormone agonist, mimic (tebufenozide) and chitin synthesis inhibitors match (lufenuron) was studied in the 2nd and 4th larval instars of the cotton leafworm Spodoptera littoralis (Bosid). Obtained results revealed that match was the more toxic against 2nd larval instars at sub-lethal concentrations LC25 and LC50 (0.3 and 0.6 ppm, respectively) than mimic (1.1 and 1.5ppm, respectively). But LC90 level was the same in the two IGRs. With respect to 4th 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 post-treatment and also with the increase in dose. Therefore, the tested IGRs, tebufenozide and lufenuron , may be not detoxify by these enzymes.2013-12-01T00:00:00ZBiological and molecular effects of pyriproxyfen, insect growth regulator (IGR), on Met gene in susceptible wild type and Met mutant Drosophila
http://hdl.handle.net/123456789/213988
Title: Biological and molecular effects of pyriproxyfen, insect growth regulator (IGR), on Met gene in susceptible wild type and Met mutant Drosophila
Authors: Bakr, Reda; Jehane A. Hafez; Thorya F. K.Alnagar; Dalia A. M. Salem; Ola H. Zyaan
Abstract: Juvenile hormone (JH) signaling pathway at the molecular level is still not well understood. Methoprene-tolerant (Met) in Drosophila melanogaster fulfills many of the requirements for a hormone receptor gene. However, Met mutant flies are resistant to insect growth regulators (IGRs). In our study, the resistance to juvenile hormone agonist (JHA) in Methoprene-tolerant (Met) mutant flies was studied. Met mutant and susceptible wild type larvae were treated by different concentrations of pyriproxyfen at 0, 0.03, 0.1, 0.3, 1, and 3 ppm. We observed that the mean percentage mortalities in Met mutant were significantly (P<0.05) lower than that in the susceptible wild type. Also, resistance in insects to IGRs due to Met gene was studied using PCR and DNA sequencing analyses. We found that there are no changes in the DNA sequences of Met gene after the treatment with pyriproxyfen.2013-12-01T00:00:00ZBiological and behavioral effects of Pyriproxyfen on pheromone production and perception. of Tribolium castaneum (Coleoptera: Tenebrionidae)
http://hdl.handle.net/123456789/213987
Title: Biological and behavioral effects of Pyriproxyfen on pheromone production and perception. of Tribolium castaneum (Coleoptera: Tenebrionidae)
Authors: Nehad M, El-barky; Olfat M. El-Monairy; Bakr, Reda; Nancy M. B. El- shourbagy.
Abstract: Pyriproxyfen (Admiral) is an insect growth regulator (IGR) acts as anti- juvenile hormone. The present work aims to investigate the toxicological effect of Pyriproxyfen on both sexes of rust red flour beetle, Tribolium castaneum resulted from treated 4th larval instar with LC50 value (2.4ppm) and its effect on female production and male's perception to pheromone. The results indicated that both treated and untreated sexes could secrete a pheromone that was able to stimulate the opposite sex as well as its own sex. But production and responsiveness of pheromone in untreated groups were significantly higher than treated one.
Females secreted a pheromone is a sex pheromone, While the pheromone secreted by males is an aggregation pheromone2012-06-01T00:00:00Z