Comparative toxicity and biochmical impacts of several convenional insecticides on Cotton leafworm.

Abstract: The objective of this research was to evaluate the susceptibility of both the laboratory and the field strain of 2nd and 4th instars larvae of the cotton leafworm Spodoptera littoralis (Boisd.) to two organophosphorus (profenofos and Chlorpyifos), two carbamates (Carbaryl and Thiodicarb) and two synthetic pyrethroid insecticides (Fenpropathrin and Beta- cyfluthrin). Based on resistance ratio the fold of resistance varied considerably according to the chemical structure of the studied insecticides and the instar of larvae. Data revealed that small differences in LC50 values were observed between the laboratory and the field strains as demonstrated by resistance ratio of 0.892, 0.939 and 0.757 fold for profenofos, Fenpropathrin and Chlorpyrifos relating to 2nd instar larvae, respectively. Thiodicarb showed the highest resistence ratio, followed by Beta-cyfluthrin and Carbaryl reached 3.843, 3.516 and 3.414 fold on the same instas larvae, respectively. The LC50 values of both the laboratory and the field strains on 4th instar larvae were remararkably higher compared with 2nd instar larvae. Cerbaryl gave the highest resistance ratio, followed by Chlorpyrifos, profenofos being 6.593, 3.721 and 3.633 fold, respectively. There were low level of resistance ratio to Thiodicarb, Beta-cyfluthrin and Fenpropathrin with degree of fold 1.061, 0.528 and 0.327, respectively. In addition the effect of tested insecticides on the activity of esterases (aliphatic esterase and a-& B-esterase), phosphatases (acid and alkaline phosphatase), transaminase (AST and ALT) and carbohydrate hydrolyzing enzymes (amylase and invertase) were evaluated on the field strain of Spodoptera littoralis (Boisd.)compared with the laboratory strain.
Publication year 2005
Availability location معهد بحوث وقاية النبات- 7 شارع نادى الصيد - الدقى
Availability number
Organization Name
City القاهرة
serial title Egypt.j.Agric Res
ISSN 1110-6336
Author(s) from ARC
External authors (outside ARC)
    ليلى رجب على الجوهرى كلية الزراعة -جامعة المنصورة
Agris Categories Pests of plants
AGROVOC
TERMS
Biochemical engineering. Cyfluthrin. Fenpropathrin. Insecticides. Organophosphorus compounds. Profenofos. Spodoptera littoralis. Toxicity.
Publication Type Journal