Establishment and yield ofminisetts of yam (Dioscorea rotundata Poir) as influenced by size and position of minisett on mother tuber and by staking in the field

Abstract

Two experiments were conducted in 1985 and 1986. Yam vines emerged earlier from the head and tail minisetts than the middle minisetts. Higher percent plant establishment recorded in bigger minisetts occurred only in those setls that originated from the head and tail positions of the mother tuber (head, middle and tail). However, there was no difference between treatments in the final percent plant establishment at 12 weeks after transplanting (WA TP), In the 1985 experiment, effect of staking on yield of yam plants derived from minisetts was significant. Yields of seed yam were, however, higher from plants derived from bigger (25-35 g) than smaller (10-20 g) setts, In 1986, this pattern was maintained. Seed yams produeed by head minisetts weighed significantly more (314.7 g/plant) than those produeed by the middle minisetts (265.8 g/plant), Tuber yield per hectare followed the same pattern. The percent yield of marketable tubers (200 g or more per tuber) from the. head minisetts (68.8 %) was similar to that from the tail (61.7 %) but differed significantly (P 0.01) from that of the middle minisetts (49.3 %), Higher percentage of marketable tubers was obtained with increase in minisett size.