基于ISSR标记的黄梅秤锤树种质资源遗传多样性分析

Germplasm Genetic Diversity of Sinojackia huangmeiensis Populations Based on ISSR Markers

黄梅秤锤树(Sinojackia huangmeiensis)属安息香科(Styracaceae)濒危保护植物。本研究以居群中最大个体为中心,在东南、东北、西南、西北4个方位采样,并依据发育阶段将其划分为成年、幼树、幼苗3个龄级居群,进行ISSR遗传多样性分析。12个标记共检测到77个位点,多态性比率为97.6%,各位点扩增条带为4~8个。其中,"幼树居群"多态性位点、Nei's基因多样性指数(h)、Shannon信息指数(I)均最高,最低的是"幼苗居群"。3个居群间遗传变异主要存在于居群内,高达89.32%。遗传一致度最高的是"幼树居群"和"成年居群",最低的是"幼苗居群"和"成年居群"。在4个方位组成的居群中,多态性位点、Nei's基因多样性指数(h)、Shannon信息指数(I)最高的是"东北居群",最少的是"东南居群"。四个方位居群仅23.37%的遗传变异发生在居群间。"东南居群"和"西北居群"的遗传距离最小,遗传一致度最大。本研究为黄梅秤锤树的生物保护、可持续开发利用等研究提供了理论依据。

Sinojackia huangmeiensis, a member of the Styracaceae family, is an endangered plant under the national protection. In this study, centred onthe maximal individual in populations, samples in southeast, northeast,southwest and northwest were collected, which were divided into three different life stages including ＇adult population＇, ＇sapling population＇, and ＇seedling population＇. ISSR markers were used to study the genetic diversity.In total, 12 markers gave out 77 loci（the number of bands of each locus ranged from 4 to 8）, and the polymorphism rate was 97.6%. In particular, the ＇sapling population＇ had the highest polymorphic loci, Nei＇s gene diversity index（h）, and Shannon information index（I）, while the ＇seedling population＇ was the lowest. Moreover, 89.32% of genetic variation existed within the 3 populations. The highest genetic identity was between ＇sapling population＇and ＇adult population＇, and the lowest was between ＇seedling population＇ and ＇adult population＇. Furthermore, the highest genetic diversity including polymorphic loci, Nei＇s gene diversity index（h）, and Shannon information index（I） was in the ＇northeast population＇, while the least was the ＇southeast population＇ among the populati onscomposed offour directions. Only 23.37% of genetic variation occurred among populations in the four populations divided according to sampling location. The genetic distance between ＇southeast population＇ and ＇northwest population＇ was the smallest, but genetic identity was the largest. This study could provide theoretical basis for the study of biological protection and sustainable utilization of S. huangmeiensis.