Integrated weed management in sorghum under South Gujarat conditions

Abstract

A field experiment was conducted during the rainy (Kharif) seasons of 2010 to 2012 in heavy black soils at Main Sorghum Research Station, Navsari Agricultural University, Surat (Gujarat), to evaluate the effect of integrated weed management in rainfed sorghum (Sorghum bicolor L.) with pre and post emergence herbicides (Atrazine, pendimethaline and 2, 4-D) alone or combination of these herbicide followed by hand weeding and intercrop soybean as smoother crop. The maximum grain (3737 kg/ha) and straw (15258 kg/ha) yields were recorded with treatment T2 (Three HW at 25, 50 and 75 DAS + IC at 50 DAS) pre-emergence application of atrazine 0.5 kg/ha + 1 HW at 35 DAS, which remained at par with treatments T5 i.e. Atrazine @ 1.5 kg/ha as pre-emergence (3612 and 14495 kg/ha), respectively and followed by T6 i.e. Atrazine @ 1.5 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (Grain yield 3448 and Stover yield 13794 kg/ha) on pooled basis. The maximum net returns (68786 Rs. per ha) was realized under the treatment T5 i.e. Atrazine @ 1.5 kg/ha as pre-emergence followed by treatments T2 i.e. Three hand weeding at 25, 50 and 75 DAS and inter-culturing operation at 50 DAS (67579 Rs. per ha) fb T6 i.e. Atrazine @ 1.5 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (65816 Rs. per ha) fb T7 i.e. Pendimethaline @ 1.0 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (62235 Rs. per ha). However, the maximum gross returns ( 97937 Rs. per ha) was recorded with treatment T2 i.e. Three hand weeding at 25, 50 and 75 DAS and inter-culturing operation at 50 DAS followed by T5 i.e. Atrazine @ 1.5 kg/ha as pre-emergence (94030 Rs. per ha) fb T6 i.e. Atrazine @ 1.5 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (89653 Rs. per ha) fb T7 i.e. Pendimethaline @ 1.0 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (86041 Rs. per ha). Whereas, the maximum B:C was recorded under the treatment T6 i.e. Atrazine @ 1.5 kg/ha as PE (2.76) fb T5 i.e. Atrazine @ 1.5 kg/ha as pre-emergence (2.72) fb T7 i.e. Pendimethaline @ 1.0 kg/ha as pre-emergence + 2,4-D @ 1 kg/ha (amine form) at 50 DAS as post emergence (2.61).