Progresses on flower bud differentiation and flower opening in Osmanthus fragrans

Abstract

Osmanthus fragrans is one of the most important ornamental plants in China. Due to the difference in the requirement to the conditions of environmental factors between flower differentiation and flower opening, these two processes are relatively independent in this species. Combining the previous references on flower bud differentiation and flower opening with our researches, we summarize the progresses on flower bud differentiation and flower opening and their environmental factors, and then simultaneously analyze the corresponding mechanism, hoping to provide an overview and useful information for approaching researches. Flower bud differentiation of one-blossom genotypes （at autumn） of O. fragrans is finished under relatively high-temperature at summer, and the relative low-temperature treatment can promote this process. The flower differentiation of autumn-blossom in multi-blossom genotypes is similar with the one-blossom ones, however the mechanism of other-season blossom is obviously different. Flowers open only after the receptivity of a certain amount of chilling at autumn. The sensitivity difference to chilling requirement among different genotypes leads to the variation of flowering time. ［Ch, 2 tab. 31 ref.］