抄録
The growth process of sweet potato plants grown directly from seed tubers were studied, comparing with that of plants growh from transplanted sprouts. The results obtained were as follows. In the directly planted plots seed tubers which were planted on the 20 th of April sprouted 20 days after planting and plants emerged on the ground 30 days after planting. Weight of seed tuber was gradually decreased up to late in June, but after that it increased, namely seed tubers thickend themselves into big anomalous tubers. Not only one of the roots developed from the seed tubers but also some plants of the roots grown from the stem became tuberous roots. Both of top and underground parts of plants in directly planted plants grew more rapidly than those of transplanted plants during the early stage of growth.
