Karpenko V. Biological substantiation of integrated application of herbicides and plant growth regulators to spring barley

The thesis being presented is a comprehensive study on physiological and biochemical, anatomic and morphological, microbiological and agro-coenocytic modes of action of herbicides belonging to different chemical classes when applied together with plant growth regulators on the productivity of spring barley plantings and the quality of spring barley yields. Economic and environmentally safe measures of their application were established. The study scientifically substantiated and proved that it was possible to decrease a negative environmental impact of herbicides belonging to classes of sylphonylurea, phenoxy-carboxylic acids and combined preparations on spring barley plantings due to their combined application with plant growth regulators. When plant growth regulators were mixed with herbicides they showed antidotal properties. It was established that applied rates of herbicide (phenoxy-carboxylic acids and combined preparations) in combinations with plant growth regulators could be reduced by 17 - 38% as compared to recommended rates. Based on the conducted research, biological substantiation for integrated application of herbicides and plant growth regulators was developed. This serves as scientific basis for the elaboration of energy efficient and environmentally safe preparation compositions ensuring an increase in the plantings productivity and quality of barley crops.