عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In order to investigate the competitive effects of wild mustard on yield and yield components of wheat cultivars, field experiments was conducted in Gorgan Reaserch Station during 2010-2012 growing seasons. The experiments were laid out in four replicated, factorial arranged RCB design. Factors of the experiments included five different densities of wild mustard (0, 4, 8, 16 and 32 plants.m-2) and four wheat cultivars (Arta,Tajan, Mogan and Morvarid). Target density of wheat considered as recommended one (350 plant.m-2) for all cultivars. The results showed that the effect of year was not significant for all studied traits, but the effect of cultivar, density and their interaction were significant. Results indicated that grain yield and yield components of wheat decreased and wild mustard biomass increased with increasing weed density from 4 to 32 plants.m-2. Also, results revealed that different varieties had different responses to decrease wild mustard biomass when interferences were considered, as Morvarid and Tajan varieties caused the highest and lowest wild mustard biomass decreasing, respectively. Results showed that in the highest density of wild mustard (32 plants.m-2), maximum and minimum tiller numbers were obtained in Morvarid and Arta cultivars, respectively. Overall, results of this study revealed that grain yield was affected more by competition than biological yield.