Morphological observation of flower bud differentiation of Dendrobenthamia hongkongensis (Hemsl.) Hutch.

To study the relationship between the external morphology of flower buds and flower bud differentiation, we used paraffin sectioning and morphological observation to observe changes in Dendrobenthamia hongkongensis (Hemsl.) Hutch. flower buds during differentiation.Results showed that the flower bud differentiation of D.hongkongensis began in early July and was completed by the end of September. The morphological differentiation process could be divided into eight periods:undifferentiated, inflorescence primordium differentiation, floret primordium differentiation, sepal primordium differentiation, petal primordium differentiation, stamen primordium differentiation, pistil primordium differentiation, pistil and stamen formation. The corresponding external morphological changes were as follows:mixed buds closed, bases of mixed buds expanded, new leaves unfolded and round inflorescences were revealed, peduncles appeared, inflorescences were enlarged, florets on the surface of the inflorescences bulged, peduncles extended to 4-6 mm, and outlines of florets became obvious. There was a certain correlation between the process of flower bud differentiation and external morphology, and flower bud differentiation could be inferred according to the external morphological characteristics of the flower buds. The aim of this study was to provide a scientific basis for flowering regulation and cultivation management of D.hongkongensis.