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Subject: Agricultural Entomology × Author: Akhtar, Shahnaz × Start date: 2000 ×
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    ThesisItemOpen Access
    BIOEFFICACY AND DISSIPATION PATTERN OF CHLORANTRANILIPROLE AND JATROPHA OIL AGAINST MAJOR PESTS OF CABBAGE
    (2023) Akhtar, Shahnaz; Choudhury, Kasturi
    The present experiment on ‘Bioefficacy and dissipation pattern of chlorantraniliprole and jatropha oil against major pests of cabbage’ was carried out during 2022-2023. The field experiment was carried out at Experimental Farm, Department of Horticulture and the laboratory experiments were carried at Residue Laboratory, Department of Entomology, Assam Agricultural University, Jorhat and Guwahati Biotech Park, Amingaon. The insecticide and botanical used in the experiment were chlorantraniliprole 18.5 SC and jatropha oil respectively. The insect pests found in field during the period Nov-Jan (2022-2023) were cabbage butterfly (Pieris brassicae), cabbage aphid (Brevicoryne brassicae), cutworm( Agrotis ipsilon), cabbage semilooper ( Trichoplusia ni), white spotted flea beetle( Monolepta signata), head borer ( Hellula undalis) and mustard aphid ( Lipaphis erysimi) and 4 species of coccinellid predators viz., red and yellow colour morphs of Coccinella transversalis, Cheilomenes sexmaculata, Harmonia dimidata and Propylea dissecta. After 1, 3, 5, 7 and 10 days of spraying, chlorantraniliprole 18.5SC @ 0.3ml/l showed maximum percent reduction of lepidopteran pests (90.70 to 92.90) followed by jatropha oil @ 7 ml/l (57.00 to 73.90) and highest infestation was observed in control. In case of Brevicoryne brassicae, the maximum percent reduction was observed in chlorantraniliprole 18.5 SC@ 0.3ml/l (74.40) which was statistically at par with jatropha oil@ 7ml/l (64.00). Chlorantraniliprole and jatroha oil had no significant effect on the population of coccinellid beetles. The highest yield was obtained from chlorantraniliprole 18.5SC @ 0.3ml/l treated plots (302.05 q ha-1), which was statistically at par with jatropha oil @ 7ml/l treated plots (299.15 q ha-1). Benefit cost ratio was also highest in jatropha oil@ 7ml/l treated plots (2.4:1). The lowest yield was obtained in control plot (111.95 q/ha). The initial deposits of chlorantraniliprole 18.5SC at 0 day was 0.44 mg kg-1 followed by 0.30, 0.15 and 0.06 mg kg-1 at 1 day, 3 days and 5 days respectively. The highest dissipation (86.36%) of chlorantraniliprole 18.5SC was recorded 5 days after spraying. The initial deposit of jatropha oil at 3 and 5 ml/l were found below detectable range while the residues of jatropha oil at 7 ml/l could be detectable only at 0 day (1hr) after spraying (0.08mg kg-1). The half-life values calculated were 1.8 days for chlorantraniliprole 18.5 SC @ 0.3 ml/l. The initial deposit of chlorantraniliprole @ 0.3ml/l was found to be below MRL. Therefore, a waiting period of 5-6 days and 1 day for chlorantraniliprole and jatropha oil, respectively has been suggested to avoid any health hazards to the consumers.