EXPERIMENTAL JUSTIFICATION OF PROSPECTS OF USING THE ENTOMOPATHOGENIC PREPARATION BOVERYN FOR THE PROTECTION OF PINETUM

Abstract

Objective. Study the possibility and feasibility of using the entomopathogenic fungal preparation Boveryn to protect pinetum from damage by pine silkworms. Methods. Field (collection of vegetation samples on the soil surface from trunk circles of model trees; collection of worms from treecrowns); laboratory (species identification, physiological monitoring). At the same time, physiologically defective samples with signs of diseases and also damaged with by worm entomophages wereremoved. They were distributed according to known characteristics, namely: size of the main capsule and age. The selected materials were placed in gauze cages with common pine branches.Worms of three species of seedworms were selected accordingly, and they were diapaused on treetrunks and in the soil. During the studies, the entomopathogenic fungal preparation Boveryn wasused with a titre of 6 billion spores/g and at a concentration of 0.5 %. Results. It was found that thelevel of entomocidal action of Boveryn against worms of different ages is determined by the speciesand age susceptibility of phytophages, as well as temperature. Accounting of the changes in parameters of the death of worms of the pine silkworm of the third generation over time shows that the population is quite vulnerable to Beauveria bassiana (Bals.) Vuill — the active substance in Boveryn. Actually, the experiment confirmed the feasibility of adding suspensions of the preparation inplaces of diapause of phytophages. At an air temperature in the range of 12–17 °C, at least 50 % ofthe pest population dies in only 9.4–12.5 days. When the temperature increases, the time of deathof worms is reduced. The digital mortality characteristics of pine silkworm worms in the fourth andfifth generations (populations of worms that feed on tree crowns) are quite informative. Conclusion. It is feasible to use Boveryn with appropriate procedure (spraying, etc.) in the areas of extensive spread of pine silkworm to ensure control of the number of pests.