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以银杏茎尖及根尖为试材，采用压片法对雌雄株核型及性别早期鉴定进行了深入研究，结果表明，①银杏雌雄株核型一致，唯一差异就是雌株第１０对亚中部着丝粒染色体的长臂上各有一个随体，而雄株这对染色体仅一条染色体具有随体，属异型染色体，即性染色体，如果用ＸＹ表示雄株这一对染色体，则雌株可用ＸＸ表示。因此，雌株核型为２ｎ＝２ｘ＝２４＝２２ＡＣ［４ｍ（２ｓａｔ）＋６ｓｍ＋１２ｓｔ］＋ＸＸ；雄株核型为２ｎ＝２ｘ＝２４＝２２Ａ［Ｃ４ｍ（２ｓａｔ）＋６ｓｍ＋１２ｓ］＋ＸＹ，进一步证实了银杏的性别决定机制属ＸＹ型；②根据ＸＹ性别决定机制，借助胚培技术对７５株银杏实生幼苗进行了性别早期鉴定，雌株为３１珠，占４１．３％，雄株为４４株，占５８．７％
The ginkgo shoot tips and root tips were used as test materials. The karyotypes and sex early identification of male and female plants were studied by using tabletting method. The results showed that ① the karyotypes of male and female ginkgo plants were the same, On the long arm of the centromere chromosome, there is a satellite, while the male one of the chromosomes has only one chromosome with the body, is a heterozygous chromosome, that is, sex chromosomes, if the male chromosome XY, said the female plant available XX said. Therefore, the karyotype of female plant was confirmed as 2n = 2x = 24 = 22AC [4m (2sat) + 6sm + 12st] + XX and the male karyotype was 2n = 2x = 24 = 22A [C4m (2sat) + 6sm + 12s] + XY According to XY sex determination mechanism, 75 early gynogenetic seedlings were identified by means of embryo culture. The results showed that the female plants were 31 beads, accounting for 41.3%, and the male plants were 44, accounting for 58%. 7%