不同种源香合欢种子和叶表型性状变异分析

Variation analysis of seed and leaf phenotypic traits of Albizia odoratissima from different provenances

【目的】通过分析不同种源香合欢种子和叶的表型性状差异,探究其地理变异规律及其环境驱动机制。【方法】以海南、广西、云南4个典型地理种源68个家系的叶片和种子为研究对象,采用多重比较、主成分分析、相关性分析等方法进行研究。【结果】各表型性状种源间叶面积变异系数最高(23.02%),叶片厚度最小(10.70%),种子的千粒重最高(16.54%),种子宽最小(5.15%);种源内云南版纳变异系数最高(16.20%),海南尖峰岭最小(10.87%)。相关性分析表明种子长与其他种子性状均呈极显著相关。结合变异系数,主成分分析和相关性分析,筛选出叶长、第2回羽状复叶叶柄长、叶脉厚、小叶长和种子千粒重、种子宽为表型变异的主要性状。叶片表型受纬度、年均气温和年均日照的影响较大,随纬度升高,年均温和年均日照逐渐降低,叶片增长变薄;种子表型受经度、纬度、海拔、年均温和年均日照影响较大,随着经度的减小,纬度、海拔的升高,年均温和年均日照逐渐降低,种子增宽增重;区域试验结果表明树高与叶长、小叶长、种子千粒重和种子宽显著相关,叶片短、种子狭长轻薄的表型特征下树高优势明显;胸径与叶片长度显著相关,羽叶较长时,胸径优势明显。香合欢表型性状变异广泛,变异来源丰富,在香合欢遗传改良过程中,要充分考虑种源间和种源内的变异分布,结合不同的育种需求选择合适的种群单株。

【Objective】The phenotypic traits of seeds and leaves of different provenances of Albizia odoratissima were analyzed to investigate the pattern of geographical variation and its environmental driving mechanisms.【Method】The leaves and seeds of 68 families of Albizia odoratissima from four typical provenances in Hainan,Guangxi and Yunnan were used for the study,and multiple comparisons,principal component analysis and correlation analysis were used.【Result】In terms of variation coefficient,the maximum leaf area was 23.02%,the minimum leaf thickness was 10.70%,the maximum 1000-seed weight was 16.54%,and the minimum seed width was 5.15%.Among all provenances,the highest variation coefficient was 16.20%in Yunnan Province and 10.87%in Jianfengling of Hainan Province.Correlation analysis showed that seed length was highly significantly correlated with all other seed traits.Combining the coefficient of variation,principal component analysis and correlation analysis,leaf length,the 2nd pinnate petiole length,leaf vein thickness,leaflet length,seed weight per thousand and seed width were selected as the main traits of phenotypic variation.The leaf phenotype is strongly influenced by latitude,mean annual temperature and mean annual insolation,and with the increase in latitude,mean annual temperature and mean annual insolation gradually decreased,and leaf growth became thinner.The seed phenotype is significantly influenced by longitude,latitude,altitude,mean annual temperature and mean annual insolation,and with the decrease in longitude,and the increase in latitude and altitude,mean annual temperature and mean annual insolation gradually decreased,and seeds became wider and heavier.The results of the regional trials showed that tree height was significantly correlated with leaf length,leaflet length,seed weight per thousand and seed width,and the individuals with short leaves and long and thin seeds showed obvious advantages of tree height.With a wide range of phenotypic trait variation and abundant sources of variation,the distribution of variation between and within provenances should be fully considered in the genetic improvement process of Albizia odoratissima,and suitable stock monocultures should be selected according to different breeding needs.