Effectiveness of selection at microtuber crop level in potato

Correlation coefficients were computed between microtuber crops and normal seed crop in order to study the selection efficiency for agronomic characters in potato at microtuber crop level. Two types of microtuber, green and white, were produced by inducing microtuberization under light and dark conditions, respectively. Genotypic differences were significant for various characters in both microtuber and normal seed crops. Green and white microtubers were equally useful for selection, judging by the crops raised from them. Selection at microtuber crop lever was found to be highly effective for plant height, stem habit, tuber colour and general impression, and moderately effective for internode length, leaf length, leaflet width, stem pigment, plant vigour and tuber shape. Selection efficiency was low for tuber yield, tuber number, average tuber weight, number of nodes, number of stems, leaf colour and number of eyes. The implications of these results for potato breeding and germplasm evaluation programmes are discussed and a procedure for selecting superior genotypes at microtuber crop level is outlined.