COMPATIBILITY OF POTATOES TO CONTRASTING SEASONAL CONDITIONS, TO HIGH-TEMPERATURES AND TO WATER DEFICIT - THE ASSOCIATION WITH TIME OF MATURATION AND YIELD POTENTIAL

Genotypic variation in the adaptation of potatoes of several maturity classes to the specific climatological conditions of the autumn season, to the high summer temperatures and to water deficit, was studied. Late-maturing cultivars exhibited the highest yielding potential both in the spring and autumn seasons but specific compatibility of cultivars to the autumn was detected. The late-maturing cultivars were more susceptible to high temperatures than were the early ones. However, there were significant differences in susceptibility to high temperatures among cultivars of the same maturity class. Susceptibility to water deficit was similar in the various maturity classes, but there were differences in the susceptibility to drought among cultivars of the same maturity class. High yielding potential generally resulted also in acceptable tuber yields under conditions of water deficit. High temperatures in combination with a water deficit aggravated yield losses, especially in the late-maturing cultivars.