2021年9月21日 星期二
南京椴天然居群的表型性状多样性及变异分析
Analyses on diversity and variation of phenotypic traits of natural populations of Tilia miqueliana
2021年 第30卷 第3期 页码[29-37]    下载全文[0.8MB]  
摘要

 以江苏省和安徽省的南京椴(Tilia miqueliana Maxim.)5个天然居群为研究对象,对其叶片、种子和果的11个表型性状进行测定,比较各居群表型性状的差异、多样性水平和变异程度;并据此进行相关性分析、主成分分析和聚类分析,以期揭示南京椴天然居群表型性状的多样性特征和变异规律。结果显示:南京椴的叶柄长、叶片长、叶片宽、种柄长、种子横径、种子纵径、苞片柄长、苞片长、苞片宽、苞果合生长度和果序柄长的均值依次为42.23、86.36、75.22、9.72、8.61、9.46、1.75、107.46、17.82、53.34和37.51 mm,不同居群间各表型性状均存在极显著(P<0.01)差异,但在居群内仅叶片长、叶片宽、苞片长和苞片宽存在极显著或显著(P<0.05)差异。11个表型性状的变异系数(CV)和Shannon-Wiener多样性指数(H′)均不同,其中,种子横径的CV值(10.80%)最小,苞片柄长的CV值(70.29%)最大,且仅种子横径和种子纵径的CV值小于15%;种柄长的H′值(1.74)最小,叶片宽和果序柄长的H′值(2.10)最大,表明南京椴种子表型性状的变异程度和多样性水平相对较低。11个表型性状的方差分量百分比在居群间的均值(43.50%)明显大于居群内(14.16%);各表型性状的居群间表型分化系数为66.12%~86.09%,其中,仅果序柄长的表型分化系数为66.12%,其他表型性状的表型分化系数均在70%以上。进一步分析结果表明:3个叶片表型性状间呈极显著正相关;在3个种子表型性状中,仅种子横径与种子纵径呈极显著正相关;在5个果序表型性状中,苞片长、苞片宽、苞果合生长度和果序柄长间呈极显著正相关。总体上看,种子表型性状与叶片和果序表型性状间大多无显著相关性,而叶片表型性状与果序表型性状间大多具有极显著或显著相关性。前5个主成分的累计贡献率达82.96%,可基本反映南京椴表型性状的大部分信息,其中,第3主成分主要反映种子特征,而第1、第2、第4和第5主成分主要反映叶片和果序的特征。基于表型性状进行聚类分析,可将5个居群分为3组,江苏省南京市牛首山和江苏省镇江市宝华山以及安徽省滁州市琅琊山3个居群聚为一组,其他2个居群各自独立成组,聚类结果与居群间的地理分布有一定关联。综合分析结果表明:南京椴天然居群的表型性状变异较为丰富,表型性状多样性水平较高,且居群间的变异是其表型性状变异的主要来源。

Abstract

 Based on 5 natural populations of Tilia miqueliana Maxim. in Jiangsu and Anhui provinces, difference, diversity level and variation degree of phenotypic traits of each population were investigated by using 11 phenotypic traits of leaf, seed and infructescence. The subsequent analyses are used to address diversity pattern and variation law of phenotypic traits of natural populations of T. miqueliana, i.e., correlation analysis, principal component analysis and cluster analysis. The results show that the averages of leaf petiole length, leaf length, leaf width, seed petiole length, seed horizontal diameter, seed vertical diameter, bract petiole length, bract length, bract width, bract and infructescence connate length and infructescence petiole length are 42.23, 86.36, 75.22, 9.72, 8.61, 9.46, 1.75, 107.46, 17.82, 53.34 and 37.51 mm, respectively. Each phenotypic trait shows extremely significant (P<0.01) difference among populations, whereas leaf length, leaf width, bract length and bract width show extremely significant or significant (P<0.05) difference within population. The coefficient of variation (CV) and Shannon-Wiener diversity index (H′) of 11 phenotypic traits are different, in which, CV value of seed horizontal diameter (10.80%) is the smallest, and that of bract petiole length (70.29%) is the largest, only that of seed horizontal diameter and seed vertical diameter are lower than 15%. H′ value of seed petiole length (1.74) is the smallest, that of leaf width and infructescence petiole length (2.10) are the largest. The CV and H′ values show that variation degree and diversity level of seed phenetic traits of T. miqueliana are lower. The average of percentage of variance component of 11 phenotypic traits among populations (43.50%) is obviously higher than that within population (14.16%). The phenotypic differentiation coefficient of each phenotypic trait is 66.12%-86.09%, in which, only that of infructescence petiole length is 66.12%, that of other phenotypic traits are above 70%. Furthermore, there are extremely significantly positive correlations among 3 leaf phenotypic traits; among 3 seed phenotypic traits, only seed horizontal diameter shows an extremely significantly positive correlation with seed vertical diameter; among 5 infructescence phenotypic traits, there are extremely significantly positive correlations among bract length, bract width, bract and infructescence connate length and infructescence petiole length. In general, most of seed phenotypic traits have no significant correlation with leaf and infructescence phenotypic traits, while most of leaf phenotypic traits have extremely significant or significant correlation with infructescence phenotypic traits. The cumulative contribution rate of the first 5 principal components is 82.96%, which can basically reflect most informations of phenotypic traits of T. miqueliana, in which, the third principal component mainly reflects the seed characteristics, while the first, second, fourth and fifth principal components mainly reflect characteristics of leaf and infructescence. Cluster analysis based on phenotypic traits shows that 5 populations are divided into 3 groups, 3 populations of Niushou Mountain of Nanjing City in Jiangsu Province, Baohua Mountain of Zhenjiang City in Jiangsu Province and Langya Mountain of Chuzhou City in Anhui Province are grouped into one group, and the other 2 populations are grouped independently, the cluster result is related to the geographical distribution of the populations. The results of comprehensive analysis shows that the phenotypic trait variation of natural populations of T. miqueliana is relatively abundant, and the diversity level of phenotypic traits is relatively high, and the variation among populations is the main source of its phenotypic trait variation.

关键词南京椴; 表型性状; 变异系数; 表型分化系数; Shannon-Wiener多样性指数; 相关性分析
Key wordsTilia miqueliana Maxim.; phenotypic trait; coefficient of variation; phenotypic differentiation coefficient; Shannon-Wiener diversity index; correlation analysis
作者严灵君, 黄犀, 岳远灏, 汤诗杰, 王欢利
所在单位江苏省中国科学院植物研究所(南京中山植物园) 江苏省植物资源研究与利用重点实验室, 江苏 南京210014
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基金项目国家自然科学基金青年科学基金项目(31700477); 江苏省自然科学基金项目(BK20170619); 江苏省林业科技创新与推广项目(LYKJ[2019]06)