Toxicity of biorational insecticides against spotted pod borer, Maruca vitrata (Geyer) in short duration pigeon pea.

摘要

The toxicity of the biorational insecticides Biobit (Bacillus thuringiensis subsp. kurstaki), lufenuron (60 g a.i./ha), NSKE (5%) and methoxyfenozide (300 g a.i./ha), along with the chemical insecticides alanycarb (500 g a.i/ha), thiodicarb (750 g a.i./ha), profenofos (1 kg a.i./ha), (1 kg/ha), lambda -cyahalothrin (25 g a.i./ha), beta -cyfluthrin (18.75 g a.i./ha), monocrotophos (400 g a.i./ha) and chlorpyrifos (700 g a.i./ha) against the spotted pod borer, Maruca vitrata, in short duration pigeon pea cv. ICPL 87 was investigated in 2 cropping seasons in Varanasi, Uttar Pradesh, India. The lowest pod damage, seed damage and seed loss was recorded in beta -cyfluthrin (5.0, 3.08, 2.72% respectively) treated plots. beta -Cyfluthrin also registered the highest grain yield (1139 kg/ha) than the other insecticides, (706-1019 kg/ha) and the control (359 kg/ha). Yield infestation analysis showed the unit pod damage and seed damage by M. vitrata and the yield loss was 43.1 and 74.7 kg/ha, respectively. The highest incremental cost benefit ratio (ICBR) was recorded in lambda -cyahalothrin (1:5.59) followed by endosulfan (1:5.48). Amongst the biorationals, B. thuringiensis subsp. kurstaki recorded the highest ICBR (1:2.80), which may be integrated in the biointensive management of M. vitrata.