The Activity of Some Detoxification Enzymes in Spodoptera Littoralis (Boisd.) Larvae (Lepidoptera – Noctuidae) Treated With Two Different Insect Growth Regulators

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.

Toxicity and Disruptive Impacts of Novaluron, A Chitin Synthesis Inhibitor, on Development and Metamorphosis of The Olive Leaf Moth Palpita unionalis

“…Some malformed pupae had been observed in non-tanned segmented body or segmented body with tanned part and incompletely tanned part, depending on the concentration level of Novaluron (see Plate 3). The currently available literature contains many reported results of toxic effects of several insect growth regulators (IGRs)(Juvenoids, ecdysteroids and chitin synthesis inhibitors, CSIs) on various insect species, such as Spodoptera littoralis by Diflubenzuron [70], Triflumuron [71], Flufenoxuron [72], Lufenuron [73,74], Buprofezin [75,76], Tebufenozide and Methoxyfenozide [77], Cyromazine [78]; Papilio demoleus by Diofenolan [79]; Eurygaster integriceps by Pyriproxyfen [80]; Dysdercus koenigii by Flufenoxuron [81]; Halyomorpha halys by Diflubenzuron [46]; Spodoptera litura by Chlorfluazuron [82]; Locusta migratoria var. manilensis by Flufenoxuron, RH-5849 and Pyriproxyfen [83]; Culex pipiens by Kinoprene [84]; Agrotis ipsilon by Flufenoxuron and Methoprene [85] or Pyriproxyfen [86] and Tribolium castaneum by Lufenuron [87].…”

Biochemical analysis and pathogenicity of entomopathogenic fungi to Diaphorina citri Kuwayama (Hemiptera: Liviidae)

“…The lowered activities of enzymes indicate that they paly no role in the breakdown of the chemicals and in contrast can enhance the vulnerability of insects to these xenobiotics (Bakr et al . 2013). Similarly, GST had significantly negative slope in relation with percent mortality for different isolates of entomopathogenic with respect to days except Bb‐01 on the third, fifth and seventh day and If‐02 on the third day.…”

Disruptive Impact of Precocene I (juvenile hormone-antagonist) on the Adult Performance and Reproductive Potential of the Egyptian Cotton Leafworm Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae)

“…Toxic effects of different IGRs on the adults have been reported in several insect species of different orders (Pineda et al, 2004;Nasr et al, 2010;Singh and Kumar, 2011;Kamminga et al, 2012;El-Naggar, 2013;Bakr et al, 2013;Hamadah et al, 2015;Tanani et al, 2015;Zhou et al, 2016;Hamaidia and Soltani, 2016;Hassan et al, 2017;Hamadah et al, 2017;Ghoneim et al, 2017a, b).…”