Efficacy of Bio-pesticides against Diamond Backmoth on Broccoli at Ambikapur, (Chhattisgarh (original) (raw)

The present investigation entitled “Population dynamics and management of major insectpests of broccoli (Brassica oleracea var italica) with special reference to diamondback moth (Plutella xylostella L)” was conducted in the Research Cum Instructional Farm of Raj Mohini Devi College of Agriculture and Research Station, Ambikapur (C.G.) during rabi 2019-20. The insect pests aphids, DBM, tobacco leaf eating caterpillar, Helicoverpa armigera, leaf webber, sawfly and whitefly were reported as major insect pests on brocolli crop. The peak population of aphids (30.60/leaf), DBM (9.00/ plant), tobacco leaf eating caterpillar (2.73/ plant), Helicoverpa armigera (1.67/leaf), leaf webber (3.07/leaf), sawfly (3.33/leaf) and whitefly (14.93/leaf) were seen during second fortnight of January, first fortnight of February, first fortnight of February, first fortnight of February, second fortnight of January, first fortnight of February and second fortnight of January, respectively. The incidence of lady bird beetle initiated from second fortnight of December (0.33/leaf) with gradual increase and attained its peak in second fortnight of January (1.13/leaf). The population gradual decreased and reached its minimum during second fortnight of March (0.27/leaf). During the period of observations it was observed that the maximum per cent plant infestation by diamond-back moth in broccoli were found in 18th march (71.1 %) followed by 4th march (68.9%). Where as during 25th December minimum per cent plant infestation (8.9 %) were observed. The overall mean larval population recorded after first and second spray revealed that T6 (spinosad 45% SC) found best treatment in respect to other treatments because it‟s recorded lowest mean larval population i.e. 4.54 larvae/plant followed by NSKE 5% (6.15 larvae/plant), Bacillus thuringiensis 2x108 (6.73 larvae/plant), Metarhizium anisopliae 2.8x106(6.77 larvae/plant), Azadirachtin 1500ppm(6.95 larvae/plant), Karanj oil 1% (7.10 larvae/plant), The highest mean larval population was observed in control plot (12.74 larvae/plant).