Studies on Bio-efficacy of Botanicals and Bio-pesticides against yellow stem borer, Scirpophaga incertulas (Walker) in Basmati Rice

Abstract

The present investigation entitled as “Studies on Bio-efficacy of Botanicals and Biopesticides against Yellow stem borer, Scirpophaga incertulas (Walker) in Basmati Rice” was conducted during Kharif, 2022 at the Crop Research Centre (CRC), Chirodi Farm of S.V.P. University of Agriculture & Technology, Meerut, U.P., India. Studies on the incidence of rice stem borer showed that the per cent dead hearts were observed highest during 36th standard week as (8.00 %) during vegetative growth phase and per cent white ears were highest during 42th standard week as (6.48%) during reproductive growth phase of the crop. The correlation matrix indicated that there was a non-significant positive correlation with maximum temperature (r=0.1801), evening relative humidity (0.4120) and non-significant negative correlation with minimum temperature (r=-0.00183), morning relative humidity (r=- 0.2193) and rainfall (r=-0.0454). Efficacy of different treatments viz, Cartap hydrochlorides 4% GR, Neem oil 3%, NSKE 5%, Beauveria bassiana 2×108 spores/ml, Bacillus thuringiensis (Bt), garlic extract 1% were found statistically superior over control in reducing the stem borer infestation and increasing the yield. The most effective treatment in reducing the stem borer infestation were Cartap hydrochloride 4%GR @ 20 kg/ha followed by Neem oil 3% @ 2.5 L/ha and NSKE 5% @ 25 kg/ha. Among biopesticides, Beauveria bassiana 2x108 @ 1.25 L/ha was found to be superior than Bacillus thuringiensis (Bt) @ 1.5 kg/ha whereas among all the pesticidal treatments, garlic extract 1% @ 5 L/ha was found to be least effective. The highest grain yield (45.40 q/ha) was obtained from Cartap hydrochloride 4% GR @ 20 kg/ha whereas higher cost benefit ratio (1:8.75) was also obtained from Cartap hydrochloride 4% GR @ 20 kg/ha, among all the treatments The lowest yield (38.10 q/ha) was obtained from garlic extract 1% @ 5lit/ha with lowest cost benefit ratio was also calculated from garlic extract 1% @ 5lit/ha with (1:2.90). Among all the treatments, Cartap hydrochloride 4% Gr @ 20 kg/ha, and Neem oil 3% were found to be more effective as compared to other treatments for the control of S. incertulas, yellow stem borer.