Transport and Metabolism of 3H-Gibberellin A1 in Dioecious Cucumber Seedlings

The transport of 3 H-GA 1 through hypocotyl segments of cucumber ( Cucumis sativus L.) was found to be nonpolar. The transport of 3 H-GA 1 was increased by pretreatment with relatively high concentrations of either IAA or Ethephon (2-chloroethylphosphonic acid). Hypocotyl segments from plants of a gynoecious genotype transported more 3 H-GA 1 than those of an androecious. The metabolism of 3 H-GA 1 in hypocotyl segments was neither related to the sex genotype of the cucumber plant nor influenced by pretreatment with Ethephon. The primary metabolite of GA 1 was suggested to be GA 8 . Two other suspected metabolites were not identified. Differences in the endogenous GA of gynoecious and androecious plants could not be accounted for by transport differences.