[The nature of the interrelations of different Bacillus thuringiensis serotypes between themselves and other species of the genus Bacillus]. / Kharakter vzaimootnoshenii razlichnykh serotipov Bacillus thuringiensis mezhdu soboi i s drugimi vidami roda Bacillus.

Intraspecies interrelations between representatives of 7 serotypes of Bacillus thuringiensis, as well as antagonistic interrelations between B. thuringiensis and 130 strains of 16 species of Bacillus bacteria were studied. Antagonistic activity was determined for 18 strains, representatives of genus Bacillus, with respect to B. thuringiensis var. tuviensis. Antagonism was the most pronounced between the strains of the alesti serotype and representatives of other serotypes as well as between the strains V. thuringiensis var. tuviensis and most of other bacillus species. Strain B. thuringiensis var. tuviensis is slightly sensitive to the action of toxic metabolites from strains of this and other species of genus Bacillus.

[Intensification of the growth and development of Bacillus thuringiensis H14 266/2-1 by optimizing the nutrient medium]. / Intensifikatsiia rosta i razvitiia Bacillus thuringiensis H14 266/2-1 putem optimizatsii pitatel'noi sredy.

The mathematical method of experimental design was used to develop a new enzymic medium for cultivation of Bacillus thuringiensis H14 266/2-1, a bactoculicide producer. The optimized medium based on corn flour enzyme lysate as a carbon source and fodder yeast enzyme lysate as a source of nitrogen amine made it possible to increase twice the titre biomass yield for 24 h cultivation as compared to the initial medium. The above medium does not yield to the initial production medium in the insecticide activity.