Impact of repeated water stress on marketable yield and total tuber yield of potato (Solanum tuberosum L.)

Potato needs frequent irrigation for its good growth and yield. The yield is greatly influenced bytiming, amount and frequency of irrigation applied. Tuber initiation stage of potato plant growth wasobserved as most sensitive to water stress because total tuber yield was reduced maximum (16%) at thisstage. Though potato yield is considered sensitive to water stress during all over growing season butperiod of tuber formation is particularly very sensitive for water stress. Tuber enlargement stage ofpotato plant was also found sensitive to water stress and registered significant reduction in marketabletuber yield (13% and 16%) and total tuber yield (9% and 11%). Stress at this stage caused significantincrease in the proportion of small non-marketable tubers. In the present study, cultivar Kufri Pukhrajwas found superior in total tuber yield among all cultivars studied under water stress conditions.