The related research of flower bud differentiation and physiological fruit drop on ‘Soshu’ persimmon

This experiment used the ‘Soshu’ sweet persimmon as the main test material, and explored the morphological characteristics of flower bud differentiation, the causes of physiological fruit drop phenomenon by applying scanning mirror, paraffin slicing technology and ultra-thin slicing technology. Our results showed that the flower bud differentiation of ‘Soshu’ persimmon was divided into five stages: the stipule primordium differentiation stage, the sepal primordium differentiation stage, the petal primordium differentiation stage, the stamen primordium differentiation stage and the pistil primordium differentiation stage, which were carried out in two years. Therefore, we should strengthen the cultivation management to improve the tree nutrient level and promote flower bud differentiation around the beginning of persimmon flower bud differentiation (in late May) and the next year germination stage. The number of flower buds gradually increased with the raise of branch length. On the same branch, the middle flower buds produced more florets than the flower buds at both ends. The degree of flower bud differentiation which was faster in the middle part of the branches was related to physiological fruit drop, the fruit drop was relatively light in the middle of the branch. Before shedding, several abscission layers were formed at the joint of the fruit and persimmon calyx. The formation of the abscission layer was one of the major reasons for the physiological fruit drop of the ‘Soshu’ persimmon. Our research provided a theoretical basis for the management of flowers and fruits and the increase in yield of the ‘Soshu’ persimmon.