chemical weed control in autumn sowing of chickpea (cicer aretinum l.) at lorestan province

a field experiment was conducted in khorramabad to evaluate the efficacy of 12 herbicides [ethalfloralin (3 l.ha-1), trifloralin (2 l.ha-1), pendimethalin (1.5-2.5 l.ha-1), imazethapyr (0.5-0.7 l.ha-1), isoxaflotole (80 g.ha-1), pyridate (2.5 l.ha-1), bentazon (2 l.ha-1), metribuzine (0.7 kg.ha -1), fomesafen (1 l.ha-1), simazine (80 g.ha-1), prometrine (830 g.ha-1), haloxyfop-r-methyl (1 l.ha-1)] applied alone or in combination for weed control, in chickpea in 2006-2007. the experiment was conducted in a randomized complete block design with four replications. the least annual weed density among chemical treatments belonged to fomesafen and isoxaflotole applied post, mixture of simazine+prometrine applied pre, and metribuzine applied pre. fomesafen and isoxaflotole applied post, and mixture of simazine+prometrine applied pre caused at least 87% reduction of weed density. pyridate applied post, reduced weed population by 85%. in the basis of visual injury, 2 and 15 days after post emergence application, bentazon applied early post, fomesafen applied post, and imazethapyr in all manure of application caused serious crop injury. isoxaflotole and fomesafen applied post, gave approximately complete control of weeds (96.5-99%). mixture of simazine+prometrine applied pre provided near complete control of wild mustard. weed dry weight for fomesafen applied post, was only 1.1% of unweeded control. fomesafen applied pre and post, pyridate and isoxaflotole applied post, imazethapyr applied pre plant and post, imazethapyr applied pre + pendimethalin applied post, bentazon applied early post, and simazine+prometrine applied pre gave very good weed control (>90% reduction in weed dry weight). at 15 days after post treatment, bentazon applied early post, caused significant reduction of stem and leaf dry weight of chickpea by 81.6 and 82.9%, respectively. isoxaflotole, fomesafen, and imazethapyr applied post, and metribuzine applied pre also caused significant crop injury. fomesafen applied pre, was safe for chickpea. maximum chickpea grain yield was recorded in hand weeding twice (1029 kg/ha) and once (984.5 kg/ha), however pyridate applied post, simazine+prometrine applied pre, pendimethalin applied pre plant incorporate, isoxaflotole applied post, metribuzine, pendimethalin, and fomesafen applied pre, pendimethalin applied post, imazethapyr, ethalfloralin and trifloralin applied pre plant incorporate, did not had significant difference with hand weeding treatments.