运用核型近似系数聚类分析方法,分析了胶蚧属7种紫胶虫的亲缘关系与系统演化。结果显示:田紫胶虫与云南紫胶虫核型似近系数为0.9688,核型同源性最大,亲缘关系最近;信德紫胶虫与紫胶蚧核型似近系数为0.9533,亲缘关系较紧密,聚在一起形成姐妹群;尼泊尔紫胶虫与普萨紫胶虫的核型似近系数为0.9441,也构成姐妹群;而中华紫胶虫的核型较为特殊,与其它6种差异较大,未能与其它种形成姐妹群关系。从核型进化上看,尼泊尔紫胶虫和普萨紫胶虫与其它5种紫胶虫的核型似近系数均小于0.7626,因此与它们亲缘关系较远,从群体中分化出来较早,属最原始的种类;信德紫胶虫与紫胶蚧出现分化的时间也较早,也属较原始的虫种;而田紫胶虫、云南紫胶虫的核型最为相似,进化距离最近,说明2者出现分化的时间最晚,属最进化的虫种;中华紫胶虫比前2者分化的时间较早,属较进化的虫种。通过对染色体核型对称性的比较,初步得出7种紫胶虫核型演化总体呈现出由不对称向着对称方向进化的趋势。
The cluster analysis method of karyotype resemblance-near coefficient was used to study the relationship and evolution of seven species in the genus Kerria. The results showed that K. ruralis and K. yunnanensis had the closest relationship with the nearest homology in karyotype. The value of λ between K. sindica and K. lacca was 0. 953 3 and the two species form a sister group, indicating a close relationship. K. pusana and K. nepalensis also formed a sister branch with the value of λ 0.944 1. The karyotype of K. chinensis is much different from the other six species and formed an isolated branch. On the evolution trend of karyotype, K. pusana and K. nepalensis were the earliest diverging members and they were the primitive species in the group as the value of λ between the two species and the others was no more than 0. 762 6. K. sindica and K. lacca also belonged to prior species as they diverged earlier than K. chinensis. On the contrary, K. ruralis and K. yunnanensis had the highest identity in karyotype and nearest distance in evolution, which showed they were the latest species of the seven-group. K. chinensis belonged to more advanced category. The evolution trend of chromosomes was approximately along the direction from asymmetry to symmetry.