Gibberellin-like substances in embryonic shoots of Scots pine in relation to generative differentiation

Abstract

Investigations were carried out on embryonic shoots of lateral and terminal buds of Scots pine (Pinus silvestris L.) of different age. at various stages of seasonal devclopment. The results show that there is a correlation between gibberellins content and apical dominance in pine. More are found in terminal buds than in lateral ones. The transition from a juvenile phase into a mature one in Scots pine is accompanied by a lowering of the gibberellin content. The formation of male inflorescences is accompanied by an increased amount of endogenous gibberellins and the appearence of a new group of non-polar gibberellin-like substances. The formation of female cones is connected with the lowering of endogenous gibberellin content.