Weed management strategies in Bt cotton under Humid Southern Plain Zone of Rajasthan

Abstract

A field experiment was conducted during two consecutive years of Kharif 2012 and 2013 at Agricultural Research Station, Banswara to find out suitable weed management strategies for Bt cotton. The experiment was laid-out in Randomized Block Design with three replications having nine treatments. Results revealed that, the application of pendimethalin 30% EC @ 0.75 kg a.i./ha PE fb quizalofop-P-ethyl 50 g a.i./ha at 20-30 DAS+one hoeing gave significantly higher bolls plant -1 (36.30), boll weight (4.22 g), seed cotton yield (2275 kg ha -1 ), net return (Rs.55581/- ha -1 ) and B:C (2.70) over rest of treatments, but it was found at par with weed free check and application of pyrithiobac sodium @ 62.5 g a.i./ha fb quizalofop-P-ethyl 50 g a.i./ha at 20-30 DAS+one hoeing bolls plant -1 (34.84), boll weight (4.19 g), seed cotton yield (2251 kg ha -1 ), net return (Rs.54669/- ha -1 ) and B:C (2.64). The maximum weed control efficiency (60.75%), lowest weed population (12.39 m -2 ) and weed dry matter accumulation (14.63 g m -2 ) at 60 DAS were observed under application of pendimethalin 30% EC @ 0.75 kg a.i./ha PE fb quizalofop-P-ethyl 50 g a.i./ha at 20-30 DAS+one hoeing over rest of treatments. However, it was found at par with weed free check and application of pyrithiobac sodium @ 62.5 g a.i./ha fb quizalofop-P-ethyl 50 g a.i./ha at 20-30 DAS+one hoeing.