Evaluation of some herbicides for weed control in wheat (Triticum aestivum L.)

Tests were conducted during 1984-85 season at two experimental sites near Riyadh to evaluate the efficiency of some post-emergence herbicides in the control of weeds in wheat (Triticum aestivum L.). The experimental sites were of loamy sand soil and were under sprinkler irrigation. The herbicides included bentazon, bromoxynil, chlortoluron, 2, 4-D, dichlorprop, diclofop-methyl, difenzoquat, isop-roturon, MCP A, metoxuron, terbutryn and some of their combinations. The bromoxynil-contained treatments (Brominal plus, Buctril M, Pardner and Brominal, each at 2.5 l/ha) were effective in controlling broad-leaved weeds, improved wheat growth and yield besides being safe and selective. Bentazonldichlorprop (Basagran DP, at 1.51/ha) was almost similar in many aspects to those contained bromoxynil, but did not appreciably improve the wheat biological or grain yield. Dic-lofop- methyl (IlIoxane) and difenzoquat (Avenge) each at 4.0 1/ha, showed effective control for grasses, and insignificantly improved the wheat growth and yield. Slight symptoms of crop phytotoxicity appeared after their application, but rapidly recovered. 2,4-DIMCP A (U-46 fluid Combi, at 1.0 l/ha) showed good control of broad-leaved weeds with slight symptoms of crop phytotoxicity and did not improve the wheat growth or yield. Isoproturon (Graminon, at 5 kg/ha), metoxuron (Dosanex, at 4.0 kg/ha), chlortoluron/ MCPA (Dicuran MA60, at 2.5 kg/ha), chlortoluron (Dicuran, at 2.5 kg/ha) and terbutryn (Igran, at 2.5 kg/ha) showed excellent control of weeds, accompanied by severe symptoms of crop phytotoxicity, that adversely affected wheat growth and yield