2021年10月27日 星期三
不同种源石斛表型性状多样性及其与地理因子的相关性
Phenotypic trait diversity of Dendrobium nobile from different provenances and their correlations with geographical factors
2021年 第30卷 第2期 页码[1-11]    下载全文[0.9MB]  
摘要

以来源于四川、贵州和云南的10个石斛(Dendrobium nobile Lindl.)种源为研究对象,对营养器官和花器官的18个表型性状进行了观测,并采用变异系数、Shannon-Wiener多样性指数和表型分化系数以及方差分析、相关性分析和聚类分析等指标和方法,对不同种源间各表型性状的表型分化程度和变异规律及其影响因子进行分析。结果表明:石斛18个表型性状的均值在多数种源间差异显著(P<0.05),其中,云南省勐腊县勐腊镇种源有10个表型性状的均值最大,且总体上与其他种源差异显著。18个表型性状的变异系数均值为8.24%~24.38%,各种源的变异系数均值为12.08%~19.02%,总体均值为14.36%。10个种源18个表型性状的Shannon-Wiener多样性指数均在3.8以上,均值为3.881~3.908。18个表型性状在种源间差异极显著(P<0.01),但种源内个体间仅茎节数、茎长、花瓣长和花瓣宽存在极显著差异;各表型性状的表型分化系数为50.00%~87.50%,均值为65.80%,且大多数表型性状的表型分化系数在57%以上。在18个表型性状中,仅茎节数、茎基部直径、茎中部直径、茎上部直径和花梗长与纬度呈显著或极显著负相关,仅叶片长和叶片宽与经度呈显著负相关,所有表型性状与海拔均无显著相关性。聚类分析结果表明:经度、纬度以及地理位置相近的种源聚在一起。在欧氏距离6.5和3.5处,分别可将10个石斛种源分为3组和4亚组,其中,组的聚类与来源地的纬度和地理位置有关,亚组的聚类与来源地的经度则有一定关系。组Ⅰ包含7个种源,纬度均在N28°范围内,位于四川南部和贵州西北部;组Ⅱ包含2个种源,纬度在N29°范围内,位于四川西南部;组Ⅲ仅包含1个种源,纬度在N21°范围内,位于云南最南端。综合分析结果表明:不同石斛种源的营养器官和花器官具有明显差异,且营养器官性状的变异水平高于花器官性状,种源间变异是其表型性状变异的主要来源;石斛的表型性状多样性丰富,但不同种源间表型性状的多样性水平接近;石斛的表型性状变异呈现以经纬度为主导的地理变异模式。

 

Abstract

Taking 10 provenances of Dendrobium nobile Lindl. collected from Sichuan, Guizhou and Yunnan as the research objects, 18 phenotypic traits of vegetative organs and floral organs were observed and measured, and  phenotypic differentiation degree and variation laws of each phenotypic trait among different provenances, and their influencing factors were analyzed by using indexes and methods of coefficient of variation, Shannon-Wiener diversity index and phenotypic differentiation coefficient as well as variance analysis, correlation analysis and cluster analysis, etc. The results show that the averages of 18 phenotypic traits of D. nobile are significantly (P<0.05) different among most of the provenances, in which, the averages of 10 phenotypic traits of provenance from Mengla Town in Mengla County of Yunnan Province are the largest, and are significantly different from other provenances in general. The average of coefficient of variation of 18 phenotypic traits is 8.24%-24.38%, that of each provenance is 12.08%-19.02%, and the overall average is 14.36%. The Shannon-Wiener diversity index of 18 phenotypic traits of 10 provenances is above 3.8, with an average of 3.881-3.908. There are extremely significant (P<0.01) differences in 18 phenotypic traits among provenances, but only stem node number, stem length, petal length and petal width are extremely significantly different among individuals within provenance; the phenotypic differentiation coefficient of each phenotypic trait is 50.00%-87.50%, with an average of 65.80%, and most of them are above 57%. Among these 18 phenotypic traits, only stem node number, basal stem diameter, middle stem diameter, upper stem diameter and pedicel length show significant or extremely significant negative correlation with latitude, only leaf length and leaf width show significant negative correlation with longitude, all phenotypic traits show insignificant correlations with altitude. The cluster analysis result shows that the provenances with similar longitude, latitude and geographical location are clustered together. At Euclidean distance of 6.5 and 3.5, the 10 D. nobile provenances can be divided into 3 groups and 4 subgroups, respectively, in which, the clustering of group is related to the latitude and geographical location of provenance, while the clustering of subgroup is related to the longitude of provenance to some degree. Group Ⅰ contains 7 provenances, and the latitudes are within the range of N28°, which are located in the south of Sichuan Province and northwest of Guizhou Province; group Ⅱ contains 2 provenances, and the latitudes are within the range of N29°, which are located in the southwest of Sichuan Province; group Ⅲ contains only one provenance, and the latitude is within the range of N21°, which is located in the southernmost part of Yunnan Province. The comprehensive analysis result shows that there are obvious differences in traits of vegetative organs and floral organs of D. nobile among different provenances, and the variation levels of vegetative organ traits are higher than those of floral organ traits, and the variations among provenances are the main source of phenotypic variation; the diversity of phenotypic traits of D. nobile is abundant, but their diversity levels among different provenances are similar; the variations of phenotypic traits of D. nobile show a geographical variation pattern dominanted by longtitude and latitude.

 

关键词石斛; 表型性状; 多样性; 变异系数; 表型分化; 地理因子
Key wordsDendrobium nobile Lindl.; phenotypic trait; diversity; coefficient of variation; phenotypic differentiation; geographical factor
作者何涛, 樊小莉, 鲁璐, 黄田钫
所在单位中国科学院成都生物研究所, 四川 成都 610041
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下载次数130
基金项目国家自然科学基金资助项目(31870308); 中国科学院科技扶贫项目(KFJ-FP-202006); 四川省科技扶贫项目(2018NFP0070)