Evaluation of Herbicides for the Control of Annual Grass Weeds in Malt Barley

Abstract

A study was conducted at Bekoji and Kofele farmer’s field in 2015/16 and 2016/17 cropping seasons to evaluate effectiveness of two post-emergence herbicides for the control of annual grass weeds in malt barley. Phenoxapropethyl 1 lit/ha, Fenoxaprop-p-ethyl 69 g/l + safener-Mefenpyr-diethyl 75 g/l 1 lit/ha, hand weeding twice (30-35 and 55-60 Days After Sowing) as a standard check and a weedy check, respectively were laid out in Randomized Block Design considering sites as a replications. Malt barley, Holker was used as a test variety. Annual grass weeds like Snowdenia polystachya, Avena fatua, Phalaris paradoxa and Setaria pumila were controlled by Phenoxapropethyl 1 lit/ha a.i and Fenoxaprop-p-ethyl 69 g/l + safener-Mefenpyr-diethyl 75 g/l a.i 1 lit/ha with an efficacy rate of 80 to 100%. Fenoxaprop-p-ethyl69 g/l + safener-Mefenpyr-diethyl 75 g/l had a yield advantage over Phenoxapropethyl and weedy check by 21 and 62%, respectively. Application of Fenoxaprop-p-ethyl 69 g/l + safener-Mefenpyr-diethyl 75 g/l a.i (23027 Birr) had higher economic benefit than hand weeding twice (22158 Birr), Phenoxapropethyl a.i (17950 Birr) and weedy check (8670 Birr) by 4, 22 and 62%, respectively. It was economically profitable with marginal rate of return of 2538% even if the price of herbicide is increased by 20% as proven by the sensitivity analysis. Hence, Fenoxaprop-p-ethyl 69 g/l + safener-Mefenpyr-diethyl 75 g/l a.i at a rate of 1 lit/ha as post-emergence application can be recommended for the control of annual grass weed species in Malt barley for agro-ecologies similar to the study areas.

Keywords: Fenoxaprop-p-ethyl 69 g/lit + safener-Mefenpyr-diethyl 75 g/lit, Grass weeds, Malt barley, Phenoxapropethyl, Post émergence herbicides

DOI: 10.7176/JBAH/9-11-06

Publication date:June 30^th 2019