Effect of osmotic stress on morphological and cultural traits of S. cerevisiae yeast cell of different ploidy

In the present study, the influence of osmotic stress on morphological and cultural traits of heterozygous tetraploid S. cerevisiae Y-503 and its daughter strain heterothallic haploid S. cerevisiae DAW-3a is considered. The belonging of Y-503 and DAW-3а to Saccharomyces taxon is confirmed by means of molecular-genetic methods. It is found that polypoid Y-503 exhibit the preferential tolerance for salinity stress, large dimensions of cells and colonies by contrast to DAW-3а. The extremely influencing factor excites a considerable activity inhibition, but not cell propagation. There is observed a great number of budding cells in Y-503 (up to 90 %).