Weed Control in Cotton through Herbicides¹

Field study on Weed Control through herbicides wai made with cotton (Gossipium spp. var. ‘Hampi’) for two seasons during 1973 and 1974, on medium black soils at the Agricultural Research Station, Siruguppa, under irrigated cropping. Ten herbicides, viz., diuron, fluometuron, dichlormate, fluchloralin, paraquat, nitrofen, alachlor, butralin, dinitramine and MSMA were tried. In these, paraquat, MSMA and diuron were tried as post-emergent, while others including diuron as pre-emergence. In the first trial, diuron at 1 kg/ha (1529 kg/ha) and fluometuron at 2.5 kg/ha (1412 kg/ha) gave better seed cotton yields than other herbicides. In the second season trial, hand weeding three times gave 2257 kg/ha of seed cotton, where as only 488 kg/ha was obtained in unweeded control. A yield of 2374 kg/ha was obtained from diuron (1 kg/ha) as pre-emergence coupled with MSMA at 1.74 kg/ha. Diuron at 0.75 kg/ha gave 2136 kg/ha of seed cotton. Generally, post-emergent herbicides were not as effective as pre-emergent herbicides owing to non-elimination of crop-weed competition during early growth stages of cotton. The major weed flora identified in the experimental area is listed.