Distribution of ¹³C-photosynthates to roots during fruit development period in vertically trained watermelon plants with two vines and one fruit

Abstract

Source-Sink relationship of photosynthates in vertically trained watermelon plants with two vines and one fruit was investigated by a ¹³C-tracer method during fruit development period. ¹³C-photosynthates were distributed to roots by leaves on a non-fruiting vine, but not on a fruiting one. Therefore, the non-fruiting vine would maintain root activity by supplying of photosynthates to roots. To prevent a physiologically acute wilting at latter period in fruit development, which should be caused by a lowering of root activity, it is suggested that increase of leaf area and/or light interception of the non-fruiting vine is more effective than that of the fruiting one in the vertically trained watermelon plants with two vines and one fruit.