Boiko M. Functional biotechnological agents Bacillus thuringiensis for colorado beetle population control

The thesis is devoted to the actual scientific problem, in particular, studying and evaluation of the entomopathogenic bacteria Bacillus thuringiensis biological effect on the Colorado beetle larvae (Leptinotarsa decemlineata Say.) for their effective use in agroproduction. In the Chernihiv Polissya conditions, field studies of the Bacillus thuringiensis 87/3 strain entomocidal activity against Leptinotarsa decemlineata Say larvae were conducted. Using the mathematical planning method of experiment, the nutrient medium for Bacillus thuringiensis 87/3 strain cultivation based on the cabbage hydrolyzate was optimized in the conditions of biolabs small tonnage production. The study of the effect of growth media (yeast-polysaccharide, molasses, cabbage hydrolyzate, MPB, LB) on the productivity of Bacillus thuringiensis strains showed different technological effect and entomopathogenic activity expression − from 2,0 to 4,8 billion spores/ ml, and from 86,0 to 99,1 % respectively. According to the field investigations results it was found that the extra-root processing apple trees of different reaches, using the bacteria Bacillus thuringiensis, reduced the number of apple scab affected leaves by 1,5−2 times. It is economically justified that phytoprotection based on Bacillus thuringiensis in the colorado beetle control system allows more efficient using of energy resources in agricultural production (the field effectiveness of the biological preparation on potato plants will be about 82,562 UAH compared with chemical preparations).