Effect of biological preparations on the decrease of insect pests on brown mustard (Brassica juncea L.)

Abstract

Abstract The article presents a study of the effect of a biological insecticide preparation containing bacteria of Bacillus Cohn genus (concentration not less than 2x109 CFU/ml3) 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 (Brassica juncea L.): Athalia rosae L., Plutella xylostella L., Meligethes aeneus 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 Athalia rosae L., in the case of Plutella xylostella L., Meligethes aeneus 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 %.