Drought stress during the growing season: Changes in reducing sugars, starch content and respiration rate during storage of two potato cultivars differing in drought sensitivity

Abstract

AbstractThe research was carried out on two potato (Solanum tuberosum L.) varieties with different tolerance to drought stress. Both varieties were cultivated in various moisture conditions: No stress, which uses the natural atmospheric conditions prevailing during the growing season and supplemented with water using drip irrigation and two combinations of drought conditions: 40 days stress at tuberizations, and intermittent drought (3 stress periods of 7 days). After harvesting, the tubers were stored at two temperatures, that is, 5°C and 8°C, for 39, 67, 143 and 164 days. The main aim of the research was the evaluation of the reaction of two potato varieties differing in drought stress tolerance to the accumulation of sugars and the respiration rate of tubers. It was found that tubers of drought stress‐sensitive variety (Cekin) accumulated more glucose and fructose than tubers of drought‐resistant variety (Tajfun), regardless of the type of drought applied during the growing season. The applied drought, both constant and intermittent, resulted in an increase in the content of reducing sugars compared with the control conditions. After applying both types of drought during the vegetation period, the respiration rate increased during tuber storage. Larger changes were recorded in the case of an intermittent drought. At a higher storage temperature, in the variety resistant to drought stress, a decrease in glucose content was found after long‐term storage, while in the sensitive variety, the content of this component increased, regardless of the moisture conditions during the growing season.