广西乐业野生春兰表型遗传多样性及利用评价

Phenotypic Genetic Diversity and Utilization Evaluation of Wild Cymbidium goeringii Germplasms from Leye County, Guangxi, China

为了解广西乐业野生春兰种质间的亲缘关系,提高其利用效率,对66份春兰种质资源的43个表型性状(13个数量性状和30个质量性状)进行多样性和相关性分析,对乐业县各来源的春兰资源进行聚类分析,并从表型性状主成分分析的基础上对其进行综合评价。结果表明:春兰种质表型多样性丰富。数量性状变异程度较高,变异系数(CV)为11.62%~41.56%,其中花梗长的CV值最高。质量性状变异系数为9.26%~55.7%,以开花习性、唇瓣主色和花瓣形状的CV值居高。说明花梗长、开花习性、唇瓣主色和瓣形都是春兰观赏性状的重点选育方向。相关性分析结果表明,花侧萼片宽(SSW)和花中萼片宽(SMW)、花侧萼片长(SSL)和花中萼片长(MSL)、花侧萼片形状(SSS)和花中萼片形状(MSS)、花瓣内侧主色(PIMC)和花萼片主色(SMC)之间呈显著正相关,相关系数分别为0.7951、0.7648、0.771、0.741;花侧萼片夹角(SSA)和侧萼片先端形状(SSPS)、唇瓣形状(LS)和中萼片先端形状(SSPS)、唇瓣色斑数量(LSN)和叶色(LC)之间则呈显著负相关,相关系数分别是–0.4557、–0.4316、–0.4181。数量性状和质量性状主成分分析分别提取5个和11个主成分,共10个因子,累计贡献率分别为78.193%和73.023%,可反映乐业春兰的总体形态表现;聚类分析结果显示,在欧氏距离为18.77处可将66份春兰种质划分为4组,其中第Ⅰ组只有一个55号品种,第Ⅱ组包含9个品种,主要以来源地相同为主,第Ⅲ组28份种质以红色花为主,第Ⅳ组28份种质,主要特征是花朵较大。研究筛选出19138-38、19138-40、18011、18007、19134-1共5份种质综合评价较高。该结果为了解广西野生春兰种质间亲缘关系及其评价与利用提供理论依据。

To understand the relationship among Cymbidium goeringii germplasms from Leye County, and to improve the utilization efficiency, genetic diversity and characteristic relativity analysis were conducted based on 43 phenotypic traits, including 13 qualitative characters and 30 quantitative characters of 66 C. goeringii germplasms. The resources were cluster-analyzed and comprehensively evaluated based on the principal component analysis of the phenotypic traits.The results showed that the phenotypic diversity of C. goeringii germplasms was rich and the trait variation was high.The coefficient of variation(CV) of quantitative characters ranged from 11.62% to 41.56%, and the highest value of CV was detected in peduncle height. The CV of qualitative traits ranged from 9.26% to 55.7%, and the value of flowering habit, lip main color and petal shape were relatively high. The results indicated that the growing peduncle height, the increasing number of flowers, the stamen petalization lip main color and petal shape were the key breeding directions of spring orchid ornamental traits. Correlation analysis indicated that there was strong positive correlation between side sepal width(SSW) and medium sepal width(MSW), side sepal length(SSL) and medium sepal length(MSL), side sepal shape(SSS) and medium sepal shape(MSS), petal inner main color(PIMC) and sepal main colour(SMC). The correlation coefficient was 0.7951, 0.7648, 0.771 and 0.741, respectively. By contrary, there was strong negative correlation between side sepal angle(SSA) and side sepal preend shape(SSPS), lip shape(LS) and medium sepal preend shape(MSPS), lip spot number(LSN) and leaf color(LC), and the correlation coefficient was –0.4557, –0.4316, –0.4181,respectively. Five and eleven principal components with 10 factors were extracted using the principal component analysis(PCA) of both quantitative and qualitative traits, and the cumulative contribution rate was 78.193% and 73.023%respectively. The phenotypic factors contained in the principal components could be used as the main character indexes for germplasm innovation and parent selection for breeding ornamental spring orchid. Based on cluster analysis, The 66spring orchid accessions were classified into four major groups when the euclidean distance was about 18.77. There was only one accession, C18019-3 in Class Ⅰ, and there were 9 accessions, mainly of the same origin, in Class Ⅱ. There were 28 accessions in Class Ⅲ and most of them were red flowers. There were 28 accessions in Class Ⅳ, and most of them had larger flowers. 19138-38, 19138-40, 18011, 18007 and 19134-1 were selected after comprehensive evaluation.The research would provide theoretical references for understanding the relationship between wild spring orchid germplasms in Guangxi and provide scientific basis for the evaluation and full utilization of resources.