Chemical Management of Bean Weeds in Crop Rotation of Bean, Phaseolus vulgaris, and Wheat, Triticum aestivum

Weeds are able to reduce bean production up to 75%. Weeding is the traditional method of weed control, which is still the most selective and complete approach. Though herbicides, due to their efficiency and economic benefit play a pivotal role in weed management. In this study the efficacy of herbicides: Imazathapyr, Thrifloralin and their mixture on bean weeds, bean reactions to different doses, application methods as well as its probable residuale effects on the following wheat crop was evaluated. Using RCBD, experiments were carried out with 9 treatments and 4 replications in 2012 and 2013 at Zanjan and Shahr-e-Kord cities. Results show that in zanjan the maximum bean yield was obtained as 4242, 3867, 3815 and 3679 kg/ha in treatments of weeding, Imazathapyr with the doses of 0.75, 0.5, and 1L/ha at pre-emergence stage respectively, whereas at Shahr-e-Kord, treatments of Imazathapyr + Thrifloralin (0.75 & 1L/ha) applied as pre-plant stage, Imazathapyr (0.75 & 0.50 L/ha) as pre-emergence application registered maximum yields of 2874, 2813, and 2694 kg/ha respectively. Pre-plant and pre-emergence applications of Imazathapyr and Thrifloralin had no injury symptoms and negative effects on wheat as the alternative plant.