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对四川８个枇杷品种：早红１号、早红３号、金丰、龙泉８０－１、龙泉１号、大五星、黄肉及早白沙的核型进行了分析。其染色体数目均为２ｎ＝２ｘ＝３４。核型可分为两大类：第１类为前７个品种，核型由中部着丝粒染色体（ｍ）和近中部着丝粒染色体（ｓｍ）组成，最长染色体与最短染色体比值均小于２，属２Ａ核型，其核型公式可表示为２ｎ＝２ｘ＝３４＝（１４～２０）ｍ＋（１４～２０）ｓｍ，表明它们具有极其近缘的关系；第２类为早白沙，核型组成除具上述两种染色体类型外，还包括两条近端部着丝粒染色体（ｓｔ），属３Ｂ核型，核型公式为２ｎ＝２ｘ＝３４＝１３ｍ＋１９ｓｍ＋２ｓｔ，在第１、２对染色体中分别存在１条近端部着丝粒染色体（ｓｔ）和１条近中部着丝粒染色体（ｓｍ），显示出该品种染色体的高度杂合性。两大类核型与枇杷品种依据果肉颜色分类基本吻合。还讨论了染色体结构变异的遗传机制。
The karyotypes of eight cultivars of loquat in Sichuan Province were analyzed: early Z.hong1, Zaohong3, Jinfeng, Longquan80-1, Longquan No.1, Zhisoxing, yellow meat and early white sand. The number of chromosomes are 2n = 2x = 34. Karyotypes can be divided into two categories: the first one is the first seven varieties, the karyotype consists of the centromere chromosome (m) and the near-center centromeric chromosome (sm), the longest chromosome and the shortest chromosome ratio were less than 2, which belongs to 2A karyotype and its karyotype formula can be expressed as 2n = 2x = 34 = (14-20) m + (14-20) sm, indicating that they have extremely close relationship; In addition to these two types of chromosome type composition, but also includes two proximal centromeric chromosomes (st), is a 3B karyotype karyotype formula 2n = 2x = 34 = 13m +19 sm +2 st, in the first and second pairs of chromosomes There are one proximal centromere (st) and one near-center centromere (sm), respectively, indicating the high heterozygosity of the chromosome of this variety. Two types of karyotype and loquat varieties based on the color of the flesh basically consistent. The genetic mechanism of chromosomal structural variation is also discussed.