Gibberellin Studies with Sugarcane. I. Cultivar Differences in Growth Responses to Gibberellic Acid¹

Abstract

The lowered radiation and temperatures of the subtropical winter season induce a physiological dwarfism in sugarcane ( Saccharum spp.). This reduction in growth can be overcome to increase yields by application of gibberellic acid (GA 3 ). In Hawaii, cultivars are commercially developed for culture in specific environmental zones defined by their mean daily radiation. In this study, cultivars selected for culture under leeward conditions of high radiation and temperatures were more dwarfed by the adverse winter conditions and gave a greater response to GA 3 than did cultivars selected for culture under the lower radiation and temperatures of higher elevations and windward zones.