The problem of valuation and selection of heat- and drought resistant genotypes on different stages of plants development is rather actual. It is known that all the plants in the growth and fruitbearing period are very sensitive to the action of high temperatures and to the lack of water. The in uence of those factors on the reproductive development stages leads to the formation of anomalous microspores and pollen grains, disturbs the function of columella and stigma surface that in its turn complicates the fertilizing process. That is why resistance of the reproductive factors to the negative environmental factors constitutes one of the most important indexes of genotypes suitability and exerts a great in uence on the productivity of most crops.