134份国外陆地棉种质主要农艺性状与纤维品质性状的遗传多样性分析

为拓宽本地棉花种质基因库,筛选适于作杂交亲本的种质资源,以134份国外棉花种质为试验材料,研究了其主要品质与农艺性状的变异情况、遗传多样性指数、品质性状间的相关性,并以主要农艺与品质性状为指标,对134份种质进行了聚类分析和主成分分析。结果表明,纤维品质性状中整齐度指数的遗传多样性指数(5.16)最高,马克隆值的变异系数(11.96%)最大,农艺性状中霜前衣分的遗传多样性指数(5.42)最高,不孕籽率的变异系数(49.18%)最大,参试种质的遗传多样性丰富;整齐度指数与上半部平均长度、断裂比强度均呈极显著正相关,断裂比强度与上半部平均长度间也呈极显著正相关;10个农艺性状和5个品质性状的主成分分析结果表明,前6个主成分的累计贡献率达75.277%;Ward法聚类将134份参试种质按品质性状分为5类,其中第Ⅱ类群的35份种质棉纤维品质性状表现最好,按农艺性状分为3类,其中第Ⅰ类群的58份种质产量最高。通过综合35份纤维品质优异的种质与58份农艺性状优异的种质筛选出美1870、美1884、FM1830等14份品质与产量俱佳的优异种质。

Analysis of Genetic Diversity of the Main Agronomic and Fibre Quality Characters of 134 Foreign Upland Cotton Germplasms

In order to broaden the gene bank and to screen germplasm resources for cross breeding,134 foreign cotton germplasms were used as experimental materials.The study involved the variation of the main fibre quality and agronomic traits,the genetic diversity index and the correlation of main quality traits.Taking the main agronomic and fiber quality characters as the index,the clustering and principal components analysis were used for these samples.The results showed that,as far as fiber quality was concerned,genetic diversity index of fiber regularity degree(5.16) was highest,variation coefficient of mcronaire value(11.96％)was highest.In terms of agronomic traits,genetic diversity index of lint percentage before the frost (5.42) was highest,variation coefficient of sterile seed ratio(49.18％)was highest,and these cotton germplasms were abundant in genetic diversity.The regularity degree was significantly positive correlated with the average length of upper half and breaking tenacity,breaking tenacity was significantly positive correlated with average length of upper half.The principal components analysis of 10 agronomic and 5 quality traits showed that the accumulation indices of top 6 principal components was up to 75.277％.Cluster analysis showed that 134 cotton germplasms were classified into 5 groups when the main quality traits were taken as the index,the group 11 had the best fiber quality.According to main agronomic characters,these germplasms were classified into 3 groups,the group Ⅰ had maximum yield.14 germplasms such as Mei1870,Mei1884 and FM1830 etc.,in which both the quality and yield traits are excellent for cross breeding have been screened by means of comprehensive analysis about 35 germplasms of quality traits and 58 germplasms of agronomic traits.