Studies on the Dry Matter Production of Sweet Potato : V. The differences in distribution ratio of dry matter produced among some varieties.

Abstract

Concentration of the three major nutrient elements in each part on dry matter basis and the distribution ratio of dry matter produced by sweet potato were determined using four varieties. In the early growing stage, it was obviously recognized that there were differences among the varieties in the distribution ratio, i.e. the percentage of the increasing weight of dry tuberous roots to the increasing amount of total dry weight; e. g. Norin No. 1 and Okinawa No. 100 showed high ratio, and Kanto No. 48 and Ibaragi No.1 showed low ratio. It appeared that most of the differences in distribution ratio among the varieties were caused by differences in nitrogen concentration in whole plant (Fig. 4). The varietal differences in nitrogen concentration were chiefly due to variation in the ratio of root dry-weight to total dry-weight as shown in figure 5.