Gibberellins of Sugarcane

Abstract

Marked qualitative differences were found in the gibberellin-like substances contained in immature stem apices and leaves of sugarcane at different stages in development and grown under various environmental conditions. Two-mo.-old cane grown under drought accumulated several gibberellin-like substances but not GA1 or GA3o. One of the substances in the 2-mo.-old cane may have been GAc5. Another compound showed very high activity in the barley endosperm assay. Four-month old sugarcane which had recommenced growth following a water stress, contained GA1 and GA3, but did not contain many of the gibberellin-like substances which had been detected in the 2-mo.-old plants. There was an absence of gibberellin-like substances in 6-mo. old, rapidly growing sugarcane tissues. The quantity of gibberellin produced in such rapidly metabolizing tissues probably is immediately used in growth.