中国沙棘染色体核型及进化研究

摘要

The chromosome karyotype of Hippophae rhamnoides Linn. ssp. sinensis Rousi was analyzed. The results indicated that the chromosome numher of H. rhamnoides ssp. sinensis was 2n=24. basic number was 12, no aneuploidy and polyploid was observed in the chromosome; The karyotype formula was 2n=24=14M+1Om, no satellites were observed in the chromosome. the relative length of the chromosome composition was 2n=4L+6M2+1OM1+4S, the karyotype belonged to "1B" type, the asymmetry coefficient of karyotype was 54％. Based on the Stebbins' evolution theory of the chromosome karyotype and the method for ordering and assignment of cladistic systematics, four important traits were analyzed. The results indicated that the evolution index of chromosome karyotype of H. rhamnoides ssp. sinensis was three. the evolution extent was low, belonging to the more primitive species; this study provided the cytology theory basis for the development of the resources. breeding and variety classification.%对中国沙棘(Hippophae rhamnoides Linn.ssp.sinensis Rousi)的染色体进行了核型分析,结果表明,中国沙棘染色体数目为2n=24,基数为12,未发现具有非整倍体和多倍体的个体;其核型公式为2n=24=14M+10m,染色体中未发现随体,染色体相对长度组成为2n=4L+6M2+10M1+4S,核型属于"1B"型,核型不对称系数As.K为54%.同时.根据Stebbins的核型进化理论和分支系统学的编序、赋值方法.对核型的4个重要性状进行了分析,结果表明,中国沙棘染色体的进化指数为3,进化程度较低,属于较原始种;这些研究结果为中国沙棘资源的开发、良种的选育和分类提供了细胞学理论依据.