Abstract
The purpose of the current study was to develop a technique to stabilize the production of seedlings or seed tubers of water yam (Dioscorea alata L.) by using vine cuttings. The effect of the time of collection of the cuttings as scions, application of gibberellic acid (GA) and uniconazol-P (UZP), an inhibitor of GA biosynthesis, to leaves of vine cuttings, on the growth of vine cuttings was investigated. The GA treatments inhibited new shoot formation of vine cuttings, regardless of the collection time as scions or concentrations of applied GA. On the other hand, shoot and mini-tuber development on the vine cuttings by UZP treatments varied with the collection time as scions. Especially, when cuttings as scions were collected at 130 days after planting, the UZP treatments led to the development of new shoots on the vine cuttings, while shoots were not observed in the control. It was considered that the UZP treatments may reduce endogenous GA synthesis in the scions and promote shoot development. UZP treatments applies to a vine cutting could be effective for the enhancement of shoot formation on vine cutting before rapid tuber enlargement of mother plant.
