新疆大蒜主栽品种的核型研究

Karyotype Study on Main Garlic Cultivars from Xinjiang, China

采用压片法对源自新疆不同地理分布区的大蒜的核型进行分析与比较研究，为新疆大蒜品种改良、新品种培育以及遗传多样性特征研究提供依据。结果表明，供试材料均为二倍体2n=2x=16，随体出现在短臂上，核型均为2A。新疆大蒜无M染色体，内地中牟大蒜有1条M染色体。源自新疆昭苏、皮山和焉耆的紫皮大蒜核型公式相同K（2n）=2x=13m＋3sm，而源自吉木萨尔的白皮大蒜与它们三者的区别在于含有1条st染色体，源自阿合奇的白皮大蒜则少1条sm染色体、多1条m染色体。核型不对称系数为55．85％～58．05％。不同地理分布区的大蒜存在染色体类型、臂比、随体的位置和数目以及相对长度组成的差异。紫皮品种染色体结构比白皮品种相对稳定。随体与大蒜的栽培季节以及生态环境存在一定的关系，染色体结构变异是造成不同地理环境间引种引起品种退化的原因之一。

In order to provide data basis for cultivar improvement, breeding and genetic divers characteristics, karyotypes of Xinjiang garlic from different geographical distribution areas were analyzed using squash ity by method. The result showed that all six materials were diploid （2n=2x=16） and the karyotype was 2A. Satellite appeared on the short arm. The difference between Xinjiang and inland garlic was whether it had M chromosome, and Zhongmu garlic had 1 M chromosome. The karyotypes of purple garlic from Zhaosu, Pishan and Yanqi were same： K（2n）=2x=13m＋3sm. The difference between the garlic from Jimusaer and them was it had 1 st chromosome. Moreover, comparing with these three, the garlic from Aheqi had 1 more m chromosome and 1 less sm chromosome. The karyotype asymmetry coefficients were 55.85%-58.05%. There were differences of chromosome type, arm ratio, satellite position, number and composition of relative length among garlic from different geographical distribution areas. The chromosome structure of purple cultivars was more relatively stable than white ones. The satellite had a certain relationship with cultivation season and ecological environments of garlic. The chromosome structure variation was one of main reasons of cultivar degeneration caused by introduction among geographical environments.