Description:
<jats:title>Abstract</jats:title>
<jats:p>The article presents a study of the effect of a biological insecticide preparation containing bacteria of <jats:italic>Bacillus</jats:italic> Cohn genus (concentration not less than 2x10<jats:sup>9</jats:sup> CFU/ml<jats:sup>3</jats:sup>) at the application rate of 5.0 l/ha with the addition of liquid fertilizers of different compositions (high-molecular weight fertilizer based on organic polymers at the rate of 5.0 l/ha and mineral fertilizer with silicon dioxide at the rate of 1.0 l/ha) and used for plant treatment on the number of insect pests of mustard (<jats:italic>Brassica juncea</jats:italic> L.): <jats:italic>Athalia rosae</jats:italic> L., <jats:italic>Plutella xylostella</jats:italic> L., <jats:italic>Meligethes aeneus</jats:italic> F. These pest species can destroy the generative organs of plants almost completely in a few days if they have a dense population in mustard sowings. We established that one treatment is sufficient for the effective decrease of <jats:italic>Athalia rosae</jats:italic> L., in the case of <jats:italic>Plutella xylostella</jats:italic> L., <jats:italic>Meligethes aeneus</jats:italic> F., there have to be two treatments of crop plants. The biological effectiveness of the biological preparation separately and in mixture with liquid fertilizer was high (at the same level as a chemical insecticide) and amounted to 92-100 %.</jats:p>