摘要
Yam, Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radiation were use to improve the size and market value of D. esculenta to promote it effective use and enhance effective conservation. We observed through repeated experiments that irradiation of yam planting material at 40 Gy gave the best results producing a M1 generation with a decreased number of tubers but with an increased tuber size per vine. Some yam characteristics are valued more than others, and prices vary across species, time, and market sites. Tuber weight exhibits an increasing marginal value and price per kilogram increases above an optimum size; therefore, yam producers and dealers derive additional reward from extra-large tubers. We conclude that, to effectively access and benefit from urban markets, producers should focus on the improved size and conical shaped-tubers, which are easy to process and meet the aesthetic qualities preferred by urban consumers. The implications for research on improved variety development to reduce poverty and for crop and resource management practices are drawn.
