Effect of Atmospheric Humidity and Soil Moisture on the Translocation of Sucrose-C14 in the Sweet Potato Plant.

Effect of atmospheric humidity and soil moisture on the translocation of foliar-applied sucrose-C14 was studied in the sweet potato plant in 1960. Sucrose-C14 was applied on a single leaf and measurements of C14 were taken after 10 hours absorption. The percentages of accumulated C14 in root were much higher at 70% air humidity than at 100% air humidity in the dark and light conditions. When roots of a sweet potato were divided into two groups and each of halves was exposed to different soil moisture for 16 hours in darkness, the translocation and storage of C14 was greater under low soil moisture (40%) than under high soil moisture (100%).