RESEARCH ON EMBRYOGENY AND CORRELATION BETWEEN EMBRYOS AND FRUIT DEVELOPMENT OF PERSIMMON

The non-astringgent persimmon cultivar of ‘Kazusa’ and the astringent persimmon cultivar of ‘Gaoanfangshi’ were used as materials to study the correlation between persimmon embryo and stamen development, and the correlation between embryo and fruit by conventional paraffin sectioning. The results were as follows: (1) persimmon had an anatropous and tenuinucellate ovule with two integuments. The persimmon embryo had single archesporial cell. Its megaspore tetrads were linear and only one of them in the chalazal had the functional role. The persimmon embryo genesis was of eggplant type, and had a polygonum type embryo sac. The zygote of persimmon embryo started to split about two weeks after dormancy. The nuclear type endosperm began to split on the third day after anthesis, and form cell wall in the early globular embryo stage as well as basically form endosperm tissue at cotyledonary embryoid stage. Moreover, there were various abortion phenomenons in the process of embryonic development; (2) in the 4 stamens anther room, anther wall was composed of the epidermis layer, fibrous layer, 1 or 2 middle layer and tapetal layer. The tapetal layer was secretory type. Meiosis of microspore mother cells was synchronous, and the tetrad arranged by tetrahedral type. Mature pollen was 2-cell. There were also various abortion phenomenons during the anther development; (3) the development of fruits and seeds was closely related to embryogenesis. Seed length and embryo length of the two cultivars had significant positive correlation. From 20 days after flowering to embryo mature, the curve equation coefficients of the fruit diameter and embryo length also had positive correlation.