Effect of auxin and other hormones on the metabolic response to wounding in sweet potato roots

摘要

In roots of sweet potato (Ipomoea batatasLam. cv. Kokei 14), the metabolic response to wounding was remarkable only in the proximal side. We assumed that the polarity resulted from a polar movement of indole-3-acetic acid (IAA) produced in the cut surface (8). As the metabolic response was slight in the distal side, the effect of IAA and the other plant hormones on the development of various enzyme activities was examined in this side. Increases in activities ofL-phenylalanine ammonia-lyase, acid invertase, NADPHa2: cytochrome c oxidoreductase, peroxidase, cytochrome c : O2oxidoreductase ando-diphenol oxidase, which developed in response to wounding, were stimulated by the treatment with IAA. Gibberellic acid had a stimulative effect on the development of only acid invertase activity. Abscisic acid and kinetin had little effect. The results strongly support our hypothesis that IAA plays an important role in the metabolic response to wounding.