Complementary study on possibility of augmentation efficacy of Total and Apyrus herbicides using time of application and wheat density

In order to complementary study of the effects of application time of two herbicides Apyrus (sulfosulfuron 75%DF) and Total (75% sulfosulfuron + 5% metsulfuron-methyl) and planting wheat density on wild barley (Hordeum spontaneum koch.) control, an experiment was conducted in randomized complete blocks design with two-factors during 2012-2013 growing season in Zarghan (Fars) and Ahvaz. The first factor was five levels of herbicide application including application of Apyrus (30 g a.i.+Citogate 1 L ha-1) and Total (5o g a.i.+adjuvant 1250 ml ha-1) at 2 to 4 leaf stage and second joint stem. The second factor was wheat density of Chamran cultivar in four levels including 400 (recommended rate), 500, 600 and seeds per m2. Results showed the effect of treatment on wild barley evaluated traits at both regions, while wheat grain yield and biological yield in Ahvaz were not affected by the different density of wheat. Results showed that application of both herbicides Apyrus and Total at second joint stem of wild barley and wheat density of 700 seeds per m2 reduced density and dry matter of wild barley up to 98% and 82% in Zarghan, while it was 95% and 79% in Ahvaz, respectively. In both regions, seed weight of wild barley after herbicide spraying at second joint stem stage was 63-75% less than the spraying at 2-4 leaf stage. In addition, wheat grain yield and biological yield in Zarghan for density of 400 seed per m2 (recommended) increased by 405 to 352 percent compared to the control, showed the best performance among different density of wheat. Overall, results of integrating wheat density and herbicide application indicated that the best treatment for controlling wild barley and obtaining high wheat yield was the application of Total at second joint stem of wild barley and planting of 400 seeds of wheat per m2.