60个甘蔗新品种(系)表型性状遗传多样性分析OA

[Objective]The study aimed to investigate the genetic diversity of newly introduced sugarcane varieties(lines)in Guigang,Guan-gxi,and to screen high-yielding and high-sugar germplasm suitable for local cultivation.[Method]A total of 60 newly introduced domestic sugarcane varieties(lines)of China were used as experimental materials,and 21 qualitative traits and 7 quantitative traits were systematically evaluated.Shannon-Weaver diversity index and coefficient of variation were calculated to perform correlation analysis,principal component a-nalysis,and cluster analysis to investigate the phenotypic genetic diversity,correlations between traits,and genetic structure of the 60 sugar-cane varieties(lines).[Result]The diversity indexes of 21 qualitative traits of the 60 sugarcane varieties(lines)ranged from 0.118 to 1.681,among them,bud shape(1.681),internode color after exposure(1.530),and internode color before exposure(1.494),along with four other traits,showed relatively rich variation.The coefficients of variation of 7 quantitative traits ranged from 7.42％to 23.36％;the coef-ficients of variation of cane yield(23.36％),millable stalk number(20.87％),single stalk weight(13.48％),and internode length(10.81％)exceeded 10.00％,indicating considerable potential for improvement.Correlation analysis showed that the plant height,single stalk weight,and millable stalk number were highly significantly positively correlated with cane yield(P＜0.01,the same as below).Stalk diameter was highly significantly negatively correlated with millable stalk number,and field Brix was significantly negatively correlated with plant height,millable stalk number,and cane yield(P＜0.05).Principal component analysis extracted 3 principal components,with a cumu-lative contribution rate of 76.833％,representing traits related to yield and sugar content,and traits related to stalk diameter and plant height,respectively.Cluster analysis classified the 60 sugarcane varieties(lines)into 4 groups;the Group Ⅳ,consisting of only Guiliu 07150,showed outstanding cane yield but relatively low field Brix,whereas Group Ⅰ,including Guitang 44,Guitang 55,Guiliu 05136,and Zhongzhe 21,performed better in the coordination of yield and sugar content.[Conclusion]The 60 sugarcane varieties(lines)exhibited con-siderable phenotypic diversity,with different quantitative traits showing both mutually promoting and mutually constraining relationships.New varieties(lines)such as Guitang 44,Guitang 55,Guiliu 05136,and Zhongzhe 21 perform better in high yield and high sugar content,proving that they are suitable candidate materials for breeding high-yielding and high-sugar sugarcane in Guigang.