Dormancy responses to post-harvest application of growth regulators inDioscoreaspecies: I. Responses of bulbils, tubers and tuber pieces of threeDioscoreaspecies

Abstract

SummaryThe effects on dormancy of post-harvest application of growth regulators to bulbils, tubers and tuber pieces of tropicalDioscoreaspecies were examined. Abscisic acid, kinetin, indole acetic acid and 2-chloroethyltrimethylammonium chloride were found to have little or no effect on either shoot or tuber-root production, while ethrel greatly promoted tuber-root production with little or no effect on shoot development. The germination of slices of tubers ofD. alatawas delayed by maleic hydrazide but there was no effect on intact tubers ofD. alataandD. esculenta. Treatment with 2,4-dichlorophenoxyacetic acid caused massive root and callus development along with delay in shoot development, while gibberellic acid occasioned marked extensions in the dormant period.