19. Physiological status and productivity of wheat plants at different density of major weeds and after herbicide treatment

Plant performance and productivity of wheat plants (cv. Sadovo 1) grown with varying density of the weeds Anthemis arvensis and Loiium perenne as well as after single and combine application by the herbicides Derby Super WG, Palas 75 WG was studied. The physiological status of plants was judged by fresh biomass accumulation, content of nitrogen, phosphorus and potassium as well as leaf gas exchange and photosynthetic pigments content. Both fresh mass accumulation and photosynthetic performance of wheat plants grown with varying weeds density were retarded, while those parameters were not significantly changed after single and combine herbicide application. Wheat grain productivity was diminished in all treatments with diffrent weed density as compared with the control (without weeds). The combined herbicide application had higher efficacy than their single use resulting in wheat productivity similar to that in the control.