Effect of atrazine, metribuzin, sulfosulfuron and tralkoxydim on weeds and yield of wheat (Triticum aestivum)

An experiment was conducted during the winter seasons of 1997–98 and 1998–99 to find out the effect of 4 herbicides on weeds and yield of wheat (Triticum aestivum L. emend. Fiori & Paol.) Of the herbicides, metribuzin being most potent killer of weeds, eliminated Chenopodium album L. and gave excellent control of all other weeds. Only this herbicide paralysed severely the growth of Convolvulus arvensis L. till harvest of the crop. The next best treatment was atrazine. Its effect on C. album was similar to that of metribuzin. It gave remarkable control of Phalaris minor Retz. but its effect on Avena ludoviciana was inconspicuous while vividly vivid on all other weed species. Isoproturon gave good control of P. minor and C. album and satisfactory control of all other weed species except C. arvensis. Sulfosulfuron proved more effective than tralkoxydim in controlling A. ludoviciana. Both the herbicides were effective against P. minor. Weed population and weed dry weight were significantly lower under weed-control treatments. The lowest was in metribuzin and it proved significantly superior to all other treatments in arresting both weed population and weed dry matter. The next best treatments were hand-weeding and atrazine. Weed competition resulted in significant decrease in wheat plant height, productive tillers/m row length, grains/panicle and 1,000 grain weight and lowered crop yield by 27.2%. All the weed control treatments caused significant increase in yield attributes and yield in both the years. Hand-weeding affected maximum increase in grain yield which proved significantly superior to all other treatments except metribuzin. (150 g/ha). No significant difference existed between atrazine (100 g/ha) and metribuzin.