Effects of age at harvest and irrigation near maturity on the incidence of internal brown fleck in potato tubers

Abstract

No brown fleck was observed in autumn-planted potatoes. The disorder developed every year in spring-planted crops, but only after the tubers matured and were left unharvested under hot conditions. With- holding irrigation in the few weeks prior to harvest reduced the incidence of brown fleck. Harvesting at maturity and 1 and 2 weeks after maturity resulted in 0, 15.3 and 26.7%, respectively, of the tubers being affected when the plots were irrigated until 2 weeks prior to harvest. When irrigation was discontinued 6 weeks before harvest, only 0, 3.8 and 4.4%, respectively, of tubers were affected in the same harvest treatments.