Integrated application of mulch and reduced doses of imazethapyr for Weed Management in Bean (Phaseolus vulgaris L.)

To evaluate the effect integrated application of mulch with reduced doses of imazethapyr on weeds in bean, a factorial experiment was conducted based on randomized complete block design with three replications and 16 treatments in Tabriz in 2015. The first factor was much application with four levels including straw mulch, living mulch, no mulch and one hand weeding and the second factor was different doses of imazethapyr including 0, 50, 75 and 100 % of recommended dose (100 g ai. ha-1). Results indicated that the interaction effects of herbicide dose and mulch application was significant on weed biomass, plant height, leaf area index and grain yield of bean. The lowest weed biomass was observed in hand weeding +100 % imazethapyr (106.5 g.m-2) that was not significantly different from straw mulch+100 % imazethapyr and living mulch +100 % imazethapyr. In 100 % dose of imazethapyr treatment, the living and straw mulch significantly increased the leaf area index of bean compared to 100 % imazethapyr. The hand weeding + 100 % imazethapyr treatment produced the highest bean grain yield (78% of weed free) and the straw mulch + 100 % imazethapyr (64% of weed free) and living mulch+ 100 % imazethapyr (53% of weed free) were the next. Generally, it could be concluded that post-emergence application of imazethapyr had low efficacy in bean weed management and using non-chemical treatments such as much and hand weeding could increase the weed control efficacy in this crop.