Abstract
The potato, cv. 'Roslin Eburu', grown as a wet season crop at Bunda College, Malawi (altitude 1100m) gave a satisfactory saleable yield of 26·3t/ha in a total growing season of 100 days. Growth analysis of the crop demonstrated that tuber initiation began soon after emergence (14 days) at average soil and air temperature of 24 to 25° and night temperatures above 15°C. It is, therefore, concluded that under tropical conditions the inhibitory effects of high temperature upon tuber initiation can be overcome by the influence of intermediate daylength (13 h) and high solar radiation. All stages of plant development, including time to emergence (14 days) and the period of bulking (50 days) were much shorter than under temperate conditions, prob-ably due to high temperature . It is suggested that higher tuber yields may be obtained by increasing tuber bulking rate (here 0·6 t/ha/day) rather than extending the bulking period. Contrary to other reports, there was no indication of tuber deformation due to high soil temperature.
