| This research choose'Nandaowuhe'litchias as study material and'Feizixiao'litchi and 'Baitangying'litchi as comparison. The embryology, morphology and endogenous hormones of the three types of fruit were thudied. Results showed that:1. The embryonic development of three types of Litch were observed and results showed that both'Nandaowuhe'and'Feizixiao'have abortion forms during their embryonic development, but in different ways. The abortion in'Nandaowuhe'generally occurs in the pre-bloom, before the formation of matured eight-nucleate embryo sac. In addition, the abortion of endosperm in'Nandaowuhe'occurred 9 days after flowering, the same period with'Feizixiao', but to a high level.2. During embryonic development, the growth rates of longitudinal diameter and transverse diameter of'Nandaowuhe'fruit before flowering 6d are different to the rate of after flowering 6d, the growth rate is very slow before this period, and then became rapidly after the division. Between 33 d and 40d after flowering, the growth rate of transverse diameter of 'Nandaowuhe'have a rapid increase over'Feizixiao'. The relationship of transverse diameter growth rate of the three varieties is'Nandaowuhe'>'Feizixiao'>'Baitangying'.3. The changes of contents of endogenous hormone in fruit during the development period were studied. The results showed:IAA, GA3 content in'Nandaowuhe'fruit are lower than'Feizixiao'and'Baitangying', and the decreased earlier than Feizixiao. But 30 days after flowering, GA3 content in'Nandaowuhe'increased rapidly close to'Baitangying'and 'Feizixiao'. ZT content in'Nandaowuhe'fruit keep at a low level in the early stage of embryonic development, and a downward trend, since rebounded slightly, but still at a low level. The contents of growth inhibitor-ABA in'Nandaowuhe'fruit is always higher than 'Baitangying'and'Feizixiao', especially during early process of embryonic development. Furthermore, (IAA+GA3+ZT)/ABA ratio in'Nandaowuhe'and'Feizixiao'always lower than'Baitangying'.
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