新疆6个天然居群野生沙棘果实性状多样性研究

Study on fruit diversity of wild seabuckthorn in Xinjiang

【目的】揭示新疆不同居群野生沙棘资源的遗传多样性和变异规律,为其开发利用和保护提供参考。【方法】对新疆阿勒泰、伊犁、阿克苏等地野生沙棘共6个居群48个单株的8个果实性状进行测量,采用变异系数、多样性指数、巢式方差分析、主成分分析等方法对其多样性进行分析。【结果】新疆野生沙棘果实性状在居群内和居群间存在丰富的多样性,居群间果实性状分化均值为37.23%,小于居群内的62.77%;性状分化系数最大的是总酸含量(65.57%),最小的是果肉颜色(5.83%)。Simpson指数和Shannon-weaver指数均为哈巴河居群最大。果实性状平均变异系数为40.11%,变异幅度为21.77%~74.34%,各性状变异系数之间差异较大,其中果实颜色平均变异系数最大(74.34%),总糖含量平均变异系数最小(21.77%)。果实颜色、种子颜色、总酸含量、总糖含量前4个主成分累计贡献率为81.46%。【结论】新疆野生沙棘果实性状存在较高的差异及分化,果实颜色的性状变异最大;居群内的变异是新疆野生沙棘果实性状变异的主要来源;哈巴河居群果实性状多样性最丰富,果实性状差异主要体现在果实颜色、种子颜色、总酸含量、总糖含量等。

【Objective】China is not only the most abundant place of the sea buckthorn plant germplasm resources, but also the center of plant differentiation, the original group and the origin of the seabuckthorn. Researches on the biological characteristics and characteristic differences of wild sea buckthorn in different areas of Xinjiang have not been reported so far. The aim of this study was to reveal the genetic diversity and variation of wild sea buckthorn resources in different populations in Xinjiang, and to provide reference for the exploitation, utilization and protection of the species【.Methods】From August to September of 2016, the mature fruits of wild sea buckthorn collected from 48 individuals from 6 populations derived from three different distribution areas of Altay, Ili and Aksu were used as research materials. 8 fruit characters（total sugar, vitamin C, total acid, ratio of sugar to acid, fruit color, flesh color,seed shape, seed color） were measured, respectively; and the morphological characteristics of fruits and seeds were observed according to the＂reference standard and data standard of sea buckthorn germplasm resources＂. The non-numerical characters were assigned and counted, separately. The coefficients of variation, relative range and population average value within and between the population variance components, phenotypic differentiation coefficients within and between the population mean square, F value and significance level were analyzed using DPS 7.05, Excel 2013 and SPSS 19.0 data processingsoftware. Furthermore, the Shannon Weaver diversity index and Simpson diversity index of fruit characters within each population were calculated separately, and the characteristic roots higher than 1 of the first 4 principal components was selected for further analysis.【Results】The average variation coefficient of fruit traits in wild seabuckthorn in Xinjiang was 40.11%, and the variation range was 21.77%-74.34%. The order of relative range and in average variation coefficient of different fruit characters was different, i.e. the variation degree between different fruit characters was different. The mean of differentiation coefficient of fruit characters between populations was 37.23%, and within the population was 62.77%. The diversity of fruit characters within populations is larger than that between populations, and variation within populations is the main source of variation of wild seabuckthorn in Xinjiang. The variation coefficients of the 8 fruit characters were different, among which the variation of fruit color was the highest（the average coefficient of variation was 74.34%）, and the relative genetic stability of the total sugar was lower（the average coefficient of variation was 21.77%）. The greatest differentiation coefficient of fruit characters was total acid（65.57%）, and the smallest one is flesh color（5.83%）. The average Shannon-weaver index and Simpson index of 6 wild seabuckthorn populations were 2.786 2 and 0.921 6, respectively. The highest fruit trait diversity was seen in the population of Habahe at 3.358 1 while the lowest was seen in the population of Zhaosu at 1.988 6. A rich genetic diversity existed between populations of wild sea buckthorn in Xinjiang. The cumulative contribution rate of the first 4 principal components of fruit traits was 81.46%, which could be used to describe most of the fruit traits.The contribution rate of principal component 1 was 23.19%, and the fruit quality index with higher load value was total acid. The contribution rate of principal component 2 was 21.62%, and the fruit quality index with higher load value was fruit color. The contribution rate of principal component 3 was 19.67%, and the fruit quality index with higher load value was total sugar. The contribution rate of principal component 4 was 16.98%, and the fruit quality index with higher load value was seed color.【Conclusion】The fruit characters of wild sea buckthorn in Xinjiang had high character difference and differentiation. The variation of fruit color was the biggest, while the variation of total sugar was the lowest.Phenotypic variation was the main source of the variation within population for Xinjiang wild sea buckthorn. The fruit trait diversity of Habahe population was the highest among the 6 population. The diversity of fruit sugar acid ratio was the highest in the 8 fruit traits. The total acid, fruit color, total sugar and seed color were the main factors that would cause the difference of fruit traits of Xinjiang wild seabuckthorn.