【摘要】 采用酶解去壁低渗法对紫背三七幼嫩根尖进行染色体数目及核型分析。结果表明,其染色体数目为2n=20,染色体基数为x=10,属于二倍体植物,核型公式是K(2n)=2x=20=20m,未观察到次缢痕或随体;没有臂比>2的染色体,染色体长度比为1.638 4,核型为1A型,属于原始类型;核型不对称系数为56.05%,核型一般比较对称;染色体相对长度组成是2n=20=10M2+8M1+2S。该研究为进一步鉴定其种质资源、栽培和良种选育奠定细胞学基础。更多还原

【Abstract】 The chromosome number and karyotype of Gynura bicolor young root tips were studied with enzymic hydrolysis method involving wall degradation and hypotonic treatment.G.bicolor was found to be diploid with the chromosome number of 2n=20,the karyotype formula of K(2n)=2x=20=20m,and basic chromosome number x=10.No satellites were found in the morphological observation of chromosomes,neither were chromosomes with arm ratio above 2.The ratio of chromosome length was 1.6384,belonging to 1Akaryotype,and primitive species.The coefficient of asymmetry was 56.05%,the chromosome was symmetrical type.The composition of relative length of chromosome was 2n=20=10M2+8M1+2S.This research provided the cytological basis for identify its germ plasm resources,further understanding,the cultivation and improved variety selection of G.bicolor.更多还原