Effects of short periods of long days on the development, yield and size distribution of potato tuber.

Abstract

Experiments were carried out to study the effects of short periods (12 or 16 cycles) of long days (24 h) on the development of stolons and tubers, and on the yield and tuber size distribution of potato cv. Bintje. Treatments initiated at an early stage of growth delayed tuber initiation but stimulated stolon elongation and stolon branching, thus increasing the number of tuber incipients. Later treatments merely delayed tuber set or tuber growth. Short treatments did not affect total tuber yield. A prolonged treatment (48 days) increased the yield in 1 of the 3 experiments. Because of these effects on stolon and tuber development, early treatments caused a shift towards smaller tubers, most pronounced when such a treatment was short. In a experiment in which physiologically old seed was used, av. tuber size was increased when the long-day treatment was initiated later. With optimally peforming seed, av. tuber size showed an optimum when the treatment was initiated just prior to or during tuber initiation. (Abstract retrieved from CAB Abstracts by CABI’s permission)