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The effect of the spores of Akanthomyces and Lecanicillium species on the behavioral responses of the greenhouse whitefly Trialeurodes vaporariorum has been studied. Three strains of the species Akanthomyces muscarius, Lecanicillium pissodis and Lecanicillium dimorphum demonstrated a strong repellency and negative effect for the adult fecundity, causing the decrease of the eggs number up to 70 % in comparison with control. Two other strains of species L. psalliotae and A. muscarius did not affect the behavioral responses and fecundity of whitefly. All studied strains showed high virulence against whitefly larvae at concentration of 5 mln spores/ml causing mortalily rate between 76 and 98 % on the 7th day after treatment. The virulence of species L. dimorphum and L. pissodis was comparable with the virulence of the species A. muscarius, they are traditionally used to produce biopreparations against whitefly. They are promising for the whitefly control. Apparently, the behavioral responses of these pests should be considered for the evaluation of the pathogenic potential of entomopathogenic fungi.

The results of studying the effect of spores and mycelium of entomopathogenic fungi of the genus Lecanicillium on the behavioral responses of predatory bugs Orius laevigatus and their fecundity are provided. In a laboratory experiment, the location of the bug adults was assessed after 24 hours, as well as the average daily fecundity of females with a free choice between a bean leaf with agar (control) and a bean leaf with sporulating fungal mycelium (experiment). It was found that the neutral reaction prevailed in the behavior of the bugs. The repellent reaction of predators was caused by the mycelium of three strains: Vl 29 (L. lecanii), ARSEF 2332 (L. dimorphum), Vit 71 (L. attenuatum); the index of aggregation ranged from -40.7 to -50 (P<0.05). Strain Vl 5 (L. lecanii), index of aggregation+43.3, caused a significant attractive reaction. The strains causing a repellant reaction of bugs did not affect the average per-day fecundity of females. Only two strains Vl 72 of L. muscarium and Vl 79 of L. dimorphum caused a significant decrease in the fecundity of O. laevigatus, while the reaction of bugs to the mycelium of these strains was neutral. In the absence of a negative effect of fungi on the fecundity of bugs, the combined use of these biological agents may be promising.

Adelgids are dangerous sucking pests of the conifers. Adelges pectinatae pectinatae and Pineus cembrae (Cholodkovsky, 1888) are noted throughout the Botanical Garden of Peter the Great on the conifers Abies sibirica, Pinus sibirica, and Pinus Banksiana. The application of entomopathogenic fungi that can penetrate into the galls of adelgids allows decreasing the usage of the chemical pesticides. Strain G-033 VIZR, which is effective against sucking insects and mites, was examined. Conifers infected by the adelgids were sprayed with the blastospore suspension (titer – 5x107 spores/ml). The number of Adelges galls was counted before treatment and weekly for a month. The effectiveness of spores on the 7th and 10th day was 20-44 %; the effectiveness of the chemical insecticide Actara was 52-99 %. By the end of the observations, the effectiveness of the biolpesticide reached 92-98% at all species of trees and was at the level of the chemical reference. The effect of the application of spores was registered over the next month. The ability of L. muscarium to cause mycosis was proved by isolating strain G-033 VIZR from the galls of Adelges infected by fungus. The strain G-033 VIZR of L. muscarium showed high efficiency and a prolonged effect on the Adelgids population of two species A. pectinatae pectinatae and P. cembrae.

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