Effective Strains of Beauveria Bassiana and B. Pseudobassiana used Against the Asian Locust (Locusta Migratoria L.) in Kazakhstan

Abstract

The purpose of the study was to perform geneticidentification of the strains of fungi of the Beauveria genus andevaluate the effect of abiotic factors on the growth and survival of coloniesand the productivity of conidia of these fungi, as well as to determine thebiological effectiveness of the semi-preparative form of the drug based on Beauveriabassiana in the field. Conventional and modern methods accepted in biologyand mycology were used. Identification of strains of Beauveria fungi wascarried out by determining the direct nucleotide sequence of the TEFregion. Laboratory experiments were carried out to evaluate various factors onthe diameter of colony growth, survival in deep and surface cultivation, thetype of semi-preparative form of the drug based on B. bassiana and thetime of its exposure, and the effect on the biological effects of drugs in thefield. Statistical data processing was carried out in the R studio programusing the P value. The productivity of conidia of entomopathogenic fungi duringsurface cultivation depended on the type of strain and the duration ofcultivation of conidia. The diameter of the growth of Beauveria fungicolonies was influenced by the factors of the strain, the type of nutrientmedium, the temperature of colony cultivation, and the number of days after thestart of colony cultivation. The survival of conidia of the B. bassianafungus on the wings of Locusta migratoria L. correlated with theindicators of cultivation temperature and germination of conidia and cultivationtime. The productivity of Beauveria spp. conidia correlate with the typeof strain, the type of substrate, and the time of exposure. The conidiacontinued to germinate on the 25^th day. Fungi grew better on asubstrate based on millet. In the field, the mortality rate of Locustamigratoria L. and the biological effectiveness of biopesticides wereinfluenced by the factors of the strain, the form of spraying with the biopreparation, and the time elapsed after treatment with the biopesticide.