Toxicity of Gibberellin to Seedless and Seeded Varieties of Vitis vinifera

Abstract

EXPERIMENTS in 1957 at the University of California showed that gibberellic acid (hereinafter referred to as gibberellin) affected set of fruit, berry size, elongation of cluster parts, fruit composition, and vegetative growth of grapes^1,2. In the spring of 1958 delayed foliation and dead buds were noted on certain seeded varieties that had received high concentrations in 1957. Observations were therefore continued for two more seasons to determine the damage and to see whether production would return to normal.