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对花椒珠心胚及胚乳的发生和发育过程进行了详细的细胞学及组织学研究。主要研究结果如下 :珠心胚发生前 ,有性胚囊发育过程中从大孢子发生到胚囊形成的各个阶段均可发生退化 ,退化频率约为 50 % ,未退化的胚囊发育成熟。成熟胚囊仅含卵器和两个极核。卵器最终退化 ,极核不经受精自发形成胚乳。当胚乳游离核达到 1 6或 32个时 ,最早的珠心胚原始细胞由靠近胚囊珠孔端的珠心细胞分化形成。随着子房生长 ,多个原始细胞持续不断地从珠孔端靠近胚囊的 1至几层珠心细胞中分化出来。珠心胚原始细胞发生频率为 2 7%。原始细胞经分裂形成多细胞原胚并进入胚囊腔中。一个胚珠中常有多个原始细胞同时发育 ,因此珠孔端常同时具有多个胚。珠心胚发育经历与合子胚相同的发育阶段。约 1 5%的种子可达到成熟。成熟种子中一般含 1～ 3个胚 ,个别种子中的胚超过 3个。
A detailed cytological and histological study was carried out on the occurrence and development of pepper heart and endosperm. The main results are as follows: Before the development of the embryo sacs, the degenerative frequency of degenerative embryo sacs could degenerate from 50% to 50% during all stages of the development of embryo sacs. Mature embryo sac contains only oviposit and two polar nuclei. Ovum eventually degenerate, polar nuclei are not fertilized spontaneously form endosperm. When the endosperm free nucleus reached 16 or 32, the earliest embryogenic primitive cells were differentiated from the peritoneal cavity near the embryo sac. As the ovary grows, multiple primitive cells continually differentiate from 1 to several layers of beads in the well near the end of the well. Pearl heart embryo blast cell frequency of 27%. Primitive cells divide to form multicellular proembryos and enter the embryo sac. A number of primordial cells in an ovule often develop at the same time, so the end of the peritoneal cavity often has multiple embryos. Pearl heart embryonic development and zygotic embryos in the same developmental stage. About 15% of the seeds reach maturity. Mature seeds generally contain 1 to 3 embryos, individual seeds more than 3 embryos.