Zdorovets E. Substantiation of a system of tobacco protection against onion thrips in the western part of the Premountainous-Littoral zone of the Crimea

The Thesis is concerned with harmfulness and nutrition preferences of onion thrips and possibility to use new insecticides of chemical and biological classes, low-volume spraying and reduced (by 30-50%) pesticide doses for control of onion thrips in tobacco. The possibility to use new chemical insecticides that have not previously been applied to control onion thrips in tobacco for the protection of that crop has been con-firmed by experiment. It has been demonstrated that those insecticides enable re-duced population numbers of the pest, a lower degree of damage caused by bronzetop of tomato and increased yields relative to the control. It has been confirmed that the biological insecticides Indocide and Bacicol can be applied in the period of growing seedings and in the field period. Optimum doses of the preparations have been established. The effectiveness of low-volume spraying to control onion thrips in tobacco has been confirmed. Techno-logical parameters of the ultralow-volume sprayer УУMO-01 that has not previously been used in agricultural crops have been developed. Optimum reduced doses of the pesticides envisaged by the spraying technique suggested have been adjusted. The economic effectiveness of the method has been determined. Tobacco cul-tivars resistant to bronzetop of tomato have been revealed, and individual factors re-sponsible for the trait have been highlighted. The main results of the research done have been tested under conditions of commercial tobacco growing.