Seed yam production from presprouted minisetts with varied thickness of storage parenchyma

A large proportion of harvested yams (Dioscorea rotundata) is used as planting material and contribute immensely to the overall cost of production. Four thicknesses (5,10,15, and 30-40 mm) of minisetts of two yam varieties were pre-sprouted in shredded coir and grown in the field to determine their suitability for producing seed yams. Variety Abi had a better sprouting ability, and more plants survived at harvest than variety Pepa. The number of sprouts/sett was highest for the thinnest (5 mm) setts. The percentage of plantsthat survived till harvest was significantly higher for the 5 mm-thick setts than 30-40mm-thick setts. In 1995, there were only slight differences among the thicknesses in totalseed yam yields. Abi produced more seed yams which weighed 400 g. Only in 1995 did the 10, 15 and 30-40 mm-thick setts yieldremarkably more tubers of 800-1000 g as compared to the 5 mm-thick setts. With the 5mm-thick setts being comparable to the other thicknesses in the yield of seed yams of150-250 g, they could be utilized for seed yam production, while more of the storageparenchyma of the tubers is used for food