Ca Antagonists Affect Root Regeneration in Cultured Melon Cotyledons

Abstract

Summary Exised melon cotyledons regenerate roots from the basal cut surface when cultured on an IAA-containing medium. If cotyledons were cultured with the calmoludin inhibitor chlorpromazin during the whole period, root regeneration and elongation were not affected. However, if the tissue was transferred from IAA-containing medium without chlorpromazin to medium with the inhibitor or the opposite at various times during the first 4 days, root elongation was affected. Of the two Ca-channel blockers, verapamil and nifedipin, the latter had a greater effect, blocking growth severely and preventing organogenesis in light cultured cotyledons of roots. Verapamil did not prevent root development, but had a similar effect as chlorpromazin, if tissue was moved from medium without inhibitor to medium with inhibitor.