Fundamental and Applied Agriculture Vol. 4(2), pp. 839–848: 2019 doi: 10.5455/faa.34774 Agronomy ORIGINAL ARTICLE Herbicidal weed control in drill sown spring wheat under Bangladesh condition Sharif Ahmed 1* , Md Jahangir Alam 2 , Tahir Hussain Awan 3 , A K M Mominul Islam 4 1 International Rice Research Institute, Bangladesh Office, Dhaka, Bangladesh 2 Regional Agricultural Research Station, Bangladesh Agricultural Research Institute (BARI), Jessore, Bangladesh 3 Rice Research Institute, Kala Shah Kaku, Punjab, Pakistan 4 Department of Agronomy, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh ARTICLE I NFORMATION Article History Submitted: 03 Mar 2019 Revised: 01 Apr 2019 Accepted: 05 Apr 2019 First online: 26 Apr 2019 Academic Editor Md Parvez Anwar *Corresponding Author Sharif Ahmed S.Ahmed@irri.org ABSTRACT Weeds are considered as one of the major factors responsible for current low wheat yield in Bangladesh. Although chemical weed control is well estab- lished in many wheat growing countries, in Bangladesh, the herbicides are typically not used by farmers to manage weeds in wheat. Hence, to evaluate the efficacy of pre- and post-emergence herbicides in mechanized drilled sown wheat, a two-year field study was conducted in southwest Bangladesh. The study evaluated the performance of four pre-emergence herbicides (oxa- diargyl 80 g, pendimethalin 850 g, pyrazosulfuron 15 g, and mefenacet + bensulfuran methyl 550 g active ingredient ha −1 ) applied at 2 days after sow- ing (DAS) and four post-emergence herbicides (2,4-D 1400 g, ethoxysulfuron 18 g, penoxsulam 22.5 g, and fenoxaprop 56 g active ingredient ha −1 ) applied at 20 DAS, on weed control efficacy. A season long weed-free and a season long weedy plots were also maintained to compare the results. The weed con- trol option using a single pre- or post-emergence herbicide was not adequate to control weed effectively when weed infestation was relatively higher. The best yield provided by pre-emergence (pendimethalin and oxadiargyl) and post-emergence (2,4-D and ethoxysulfuron) herbicide treatments were respec- tively 13-15% and 12-17% lower than the yield (4.1-4.2 t ha −1 ) of weed-free treatment. Post-emergence herbicides fenoxaprop was the best in controlling weeds; however, due to phytotoxic effects on wheat plants, the plots applied with fenoxaprop produced very low yield (2.6-2.8 t ha −1 ). Similarly, even after good weed control by the post-emergence application of penoxsulam, phytotoxicity on wheat resulting in low yield. The study suggested that the best weed control option for wheat is to use a pre-emergence (pendimethalin or oxadiargyl) followed by (fb) a post-emergence (2,4-D or ethoxysulfuron) herbicides depending upon weed species which would benefit the farmers by providing high weed control efficacy at lower cost compared to manual weeding. Keywords: Weed shift, weed control efficiency, herbicide toxicity, yield gap, wheat Cite this article: S Ahmed, Alam MJ, Awan TH, Islam AKMM. 2019. Herbicidal weed control in drill sown spring wheat under Bangladesh condition. Fundamental and Applied Agriculture 4(2): 839–848. doi: 10.5455/faa.34774