The Effect of Genotype Combinations of and Its Host on Fertility, Developmental Rate and Heat Stress Resistance of Flies.

The best-known effect of the intracellular bacterium is its mostly negative influence on the reproduction of the host. However, there is evidence of a positive influence of on the host's resistance to stress, pathogens, and viruses. Here, we analyzed the effects of two strains belonging to wMel and wMelCS genotypes on traits, such as fertility, survival under acute heat stress, and developmental rate. We found that lines under study differ significantly in the above-mentioned characteristics, both when the natural infection was preserved, and when it was eliminated. One of strains, wMel, did not affect any of the studied traits. Another strain, wMelPlus, had a significant effect on the development time. Moreover, this effect is observed not only in the line in which it was discovered but also in the one it was transferred to. When transferred to a new line, wMelPlus also caused changes in survival under heat stress. Thus, it could be concluded that - interaction depends on the genotypes of both the host and the symbiont, but some effects could depend not on the genotypes, but on the fact of recent transfer of the symbiont.