Peanuts: gibberellin antagonists and genetically controlled differences in growth habit.

Treatment of peanuts with gibberellin changed the orientation of lateral branches of runners to that of erect ones, and two growth retardants changed those of the erect type to a more horizontal orientation. Little or no difference was found in amounts of endogenous gibberellin in the two types of plants, but amount of native gibberellic acid antagonists was higher in runner plants. Furthermore, runner plants contained a particular gibberellic acid inhibitor not found in erect plants. Applications of various auxins, antiauxins, and a cytokinin had no effect on tropistic growth of the side branches.