Investigation of application timing and herbicide rate of Isoxaflutole (SC 480) for broadleaved weeds control in spring chickpea in dryland condition

In order to evaluate the efficacy of Isoxaflutole (SC480) on weed control in Chickpea (Cicer arietinum L.) fields, experiments were carried out in Kermanshah, Kurdestan and Lorestan provinces in a randomized complete block design with four replications. Treatments consisted of applications of pre-emergence isoxaflutole (SC480) at 0.2, 0.3 and 0.4 L.ha-1 of commercial formulation, post-emegence isoxaflutole at 0.2, 0.3 and 0.4 L.ha-1 of commercial formulation, post-emergence pyridate (EC60%) at 2 L.ha-1 of commercial formulation and hand weeding. Weed percent damage based on EWRC scores at 30 days after post spraying, weed density reduction (%), weed biomass reduction (%) were measured. According to the results, the best treatments in Kermanshah for grain yield of chickpea were pre-emergence isoxaflutole at rates 0.2 and 0.3 L.ha-1 with 669 and 632.5 kg ha-1 that reduced weed density %79 and %80.5 respectively. In Kurdestan, pre-emergence isoxaflutole at rate 0.2 L.ha-1 was considered as the most suitable treatment with 80% reduction in weed density and 1118 kg ha-1 grain yield. In Lorestan, pre-emergence isoxaflutole at rate 0.2 and 0.3 L.ha-1 reduced weed population at 89.5% and 91.5% respectively. The highest grain yield in Lorestan belonged to pre-emergence isoxaflutole at rates 0.2 and 0.3 L.ha-1 at 742 and 812.5 kg.ha-1.According to the results in the three locations, application of pre- emergence isoxaflutole at rate 0.2 L.ha-1 of commercial formulationis suitable for weed control in spring chickpea.