荔枝的胚胎学研究

EMBRYOLOGICAL STUDIES OF LITCHI CHINENSIS

The present paper deals with the embryology of Litchi chinensis Sonn. The results are summarized as follows: The ovule is anatropous, with 2 integuments, obturator present, crassinucellar, archesponal functioning directly as the megaspore mother cell. The chalazal megaspore is functional. The development of the embryo sac conforms to the normal type. The formation of the microspores is of successive type. Mature pollen grain is 2-celled. The wet stigma surface has many papillar cells. The polar nuclei fuse before fertilization. Two sperms fuse with egg cell and secondary nucleus respectively 64 hours after pollination. Three antipodal cells are ephemeral. The endosperm is of nuclear type. The aril originates from the outer integument. Zygote of the small seeded varieties degenerated; but that of the large seeded varieties develops normally into mature embryo.