贵州核桃种质资源表型性状多样性研究

Phenotypic Traits Diversities of Walnut Germplasm Resources in Guizhou

该研究以贵州省内的3个山脉(乌蒙山、苗岭山和武陵山)、19个核桃和泡核桃实生居群、245棵实生单株为研究材料,对坚果表型性状29个指标的多样性、相关性、聚类及变异进行分析,以揭示贵州核桃资源的表型遗传多样性水平,为贵州核桃资源的保存与利用及核心种质构建提供依据。结果显示:(1)核桃和泡核桃实生居群245份种质资源的18个表型质量性状Simpson指数为0.26~0.82,Shannon-Wiener指数为0.12~1.79;核桃小叶形状多样,易发生顶叶退化,坚果核壳表面特征、坚果形状及核仁皮色多样性丰富。(2)坚果表型变异系数为3.32%~47.67%,平均为21.28%且差异显著(P<0.05),居群间变异系数为9.42%~31.61%且差异显著(P<0.05);居群内和居群间变异均是核桃表型多样性的来源,但坚果性状在居群间差异显著性均高于居群内,说明居群间变异是该区域坚果表型变异的主要来源。(3)3个山脉区域核桃表型均有不同程度变异,其中,苗岭山核桃表型变异程度低,乌蒙山核桃表型变异程度高;UPGMA聚类结果显示,19个核桃实生居群依据贵州山脉区域划分为三类,表明贵州核桃资源的坚果表型性状平方欧氏距离表现出与地理区域或气候条件呈正相关的趋势。研究认为,贵州具有丰富的核桃种质资源,且核桃表型多样性高,其表型变异主要来源于居群间变异。

This study took 3 mountain ranges(Wumeng mountain,Miaoling mountain and Wuling mountain),19 walnut and iron walnut populations,and 245 individual plants in Guizhou Province as the research materials,and analyzed the diversity,correlation,clustering and variation of 29 nut phenotypic traits,in order to reveal the phenotypic genetic diversity level of walnut resources in Guizhou,and provide a basis for the conservation and utilization of walnut resources in Guizhou and the construction of core germplasm.The results showed that:(1)the Simpson index of 18 phenotypic quality traits of 245 germplasm resources of walnut and iron walnut were 0.26-0.82,and the Shannon-Wiener index was 0.12-1.79.The shape of walnut leaflet was diverse,and parietal leaf degeneration was prone to occur,Nut shell surface characteristics,nut shape and Walnut skin color were rich in diversity.(2)The coefficient of variation of nut phenotype is 3.32%-47.67%,the average is 21.28%and the difference is significant(P<0.05),the coefficient of variation between populations is 9.42%-31.61%and the difference is significant(P<0.05).Intra-population and inter-population variation is the source of walnut phenotypic diversity.However,the differences in nut traits between populations were significantly higher than those within population,indicating that inter-population variation was the main source of nut phenotypic variation in this region.(3)The phenotypes of walnuts in the three mountain regions have different degrees of variation,among which,the Miaoling Mountain had a low degree of walnut phenotype variation,while the Wumeng mountain had a high degree of walnut phenotypic variation.UPGMA clustering results showed that the 19 walnut populations were divided into three categories according to the Guizhou Mountain range,indicating that the square European distance of the nut phenotypic traits of Guizhou walnut resources showed a positive correlation with the geographical region or climatic conditions.It is believed that Guizhou is rich in walnut germplasm resources and has high phenotypic diversity,and its phenotypic variation mainly comes from inter-population variation.