Influence of moisture on the toxicity of some biopesticides on Bombyx mori L.
2009
Chatterjee, Hirak
Adverse effect of moisture on some microbial insecticides such as Halt (Bacillus thuriengiensis var kurstaki, B.t.k.- 55000 S.U./mg), Biolep (B.t.k.- 32000 I.U. /mg), Vertimec (product of Streptomyces avermitilis - Avermectin- 1.8% w/v) and Bassina (formulation of Beauvaria bassiana-1 x 107 spore / ml) were studied against third instar larvae of mulberry silkworm, Bombyx mori L. under four levels of relative humidity ( 30%, 60%, 80% and 90% R.H.) and constant temperature (20 0C ± 2 0C). The biocide avermectin at 1000 ppm caused 96.66% and 95.00% mortality after 72 h of treatment at 80% and 90% relative humidity respectively. Whereas, halt and biolep caused 95.00%, 90.00% and 81.66%, 80.00% mortality after 72 h at the two respective humidies level. Through fungal formulation of B. bassiana proved to be less harmful against B. mori at 30% and 60% R.H. it inflicted 40 _ 43.33% mortality at higher moisture level (70% R.H.). Relative humidity was found to play a major role towards pathogenecity of all the tested microbials against B. mori. Increasing mortality was recorded with increase in days after treatment and maximum effect was noticed at 80% R.H. The overall effect followed the same trend for all the microbial insecticides, and the observed descending order was Avermectin Halt biolep B. bassiana at four levels of relative humidity, respectively.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل Indian Council of Agricultural Research