Abstract
The aim of the present study is to investigate the effect of time of application of herbicide tribenuron-methyl (granstar) in high concentrations on the growth and productivity of wheat seed Triticum aestivum L .varity (IPa-95). The experiment contain tow factors. The first factor, concerns with the time of application (early and late) and the other ones is different concentrations of herbicide (0.0% (distal water),0.5%,0.8%,1%)(g/ml).The results showed that a significant decreasing at 0.05 level of significance in growth and yield components except for number of stomata (no./mm2) when herbicide was used in a high concentrations. On other hand , early application of herbicide led to a significantly decrease for the height of plant (cm) , spike length (cm) and chlorophyll a (mg/gm tissue) compared with late herbicide application . However , there is no significant effect to the herbicide concentrations on all traits when its application (early and late). Moreover , the interaction between the two factors (concentrations x applications) were significantly high on all parameters including chlorophyll a and b at only in early application . .At the last applied that the inhibition effect from herbicide concentrations in the early application was more obvious on plant height , spike length and chlorophyll a than at late application of herbicide .
