SEED VIGOUR AND ROOT SYSTEM SIZE AS A ATTRIBUTE FOR DROUGHT ESCAPE AND TOLERANCE

Seed vigour is the ability of seeds to germinate and form the basis for future plant growth and development in standard and stressed conditions (drought, low temperatures, lack of nutrients). The root system size of 39 winter wheat genotypes (Triticum aestivum L.) planted in field experiment was evaluated in relation to the seed germination and seed vigour and grain yield. Statistically significant inter-varietal differences in average root system size values from the entire growing season were found. Positive relationship between root system size in the grain filling stage and germination of harvested seed was confirmed for early genotypes. Root system size of late genotypes was statistically significantly associated with seed vigour. Grain yield was not affected by the seed vigour and seed germination of sown seeds, but by the root system size. Genotypes with a higher average values of root system size and root system size at stem elongation stage achieved higher grain yield. It is possible to provide selection for cultivar tolerance to stress already at the seed germination stage and on the quality of plant root systems. Seed vigour and quality of the embryonic roots is important for the following growth and plant development.