都市园林植物云南樱花的表型多样性研究

Phenotypic diversity of urban landscape plant Prunus yunnanensis

关键词:  云南樱花, 栽培居群, 观赏植物, 变异, 种质选育

Key words:  Prunus yunnanensis, cultivated population, ornamental plant, variation, germplasm selection and propagation

摘要:

云南樱花(Prunus yunnannensis)为蔷薇科(Rosaceae)多年生落叶乔木,是中国西南地区特有的重要园林观赏植物,其在昆明园林绿化中具有较高的应用价值。以昆明地区的云南樱花为研究对象,研究了6个栽培居群120个单株的16个表型性状的多样性,分析了16个表型性状的相关性和广义遗传力,并对6个栽培居群进行了聚类分析,旨在探明其在资源应用过程中的表型变异程度及变异规律,为今后优良性状选育与种质推广提供科学依据。结果表明:云南樱花在居群间及居群内均存在丰富的表型多样性,除雌蕊长以外,其它15个表型性状在各居群之间均存在显著性差异,其中各性状的平均变异幅度为7.73%～94.04%,在居群内的变异幅度为20.74%～28.22%,各性状居群内的变异明显小于居群间,16个表型性状的广义遗传力介于0.54～0.97之间,其中叶长的广义遗传力最大,而雌蕊长的广义遗传力最小。对云南樱花16个形态指标的相关性分析表明,大部分形态指标之间均存在显著的相关性。利用居群间欧氏距离进行的UPGMA聚类分析结果表明,云南樱花6个栽培居群可以聚为2类。

Abstract:

Investigation of intraspecific phenotypic diversity is critical for the understanding of evolutionary and ecological processes, and may provide insights for uncovering the roles of natural selection, genetic diversity and variation that contribute to species' variety breeding and resource exploitation and utilization. Prunus yunnannensis is a perennial deciduous plant in the family Rosaceae. It is an endemic germplasm resource with high ornamental value in Southwestern, China. The species has been widely implicated as an ornamental plant in city landscaping in Kunming, Yunnan Province. In order to reveal the variation degree and variation patterns of the phenotype in P. yunnannensis during resource application and provide scientific evidence for species' breeding and germplasm utilization, we investigated 16 phenotypic traits, including 12 flower characters and 4 foliage traits, of 120 individuals in 6 cultivated populations of P. yunnannensis from Kunming City. Furthermore, the phenotypic traits variations and relationships were also analyzed. In addition, UPGMA based cluster analysis was performed using the phenotypic data. The broad heritability of these phenotypic traits was also calculated in the present study. The results showed that there were significant differences in the phenotypic variation among and within populations. All phenotypic traits had significant differences among the populations except for the phenotypic index of pistil length. Specifically, the coefficient of variation of these phenotypic traits varied from 7.73% to 94.04%, while it varied from 20.74% to 28.22% within populations. The variation of the phenotypic traits was lower within populations than that among populations. The broad heritability of 16 phenotypic traits ranged between 0.54 and 0.97. The leaf length has the highest value, while the pistil length has the lowest value of broad heritability, with the ordering of LL>LW>PETL>PLEF>PW>FBL>FI>FD>PEL>VN>SN>PN>FN>PL>SL>PIL. The correlation analysis showed that there were significant correlation among most phenotypic traits. UPGMA cluster analysis based on phenotypic traits showed that the 6 cultivated populations could be divided into two groups. The reasons that caused the phenotypic traits variation of P. yunnannensis were also discussed.