Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences
National Natural Science Foundation of China（31571618, 31771734），National Bast Industry Technology System Construction Special Project（CARS-16-E12），Supported by the Fundamental Research Funds for the Central Research Institutes (1610242021005)
The evaluation of fiber yield related traits in ramie can provide scientific basis for molecular marker selection breeding and elite germplasms on genetic improvement of ramie varieties with high fiber yield. In this study, 298 ramie germplasm accessions from different sources were used for the field trials at three seasons, followed by data collection, frequency distribution histogram analysis, coefficient of variation analysis, correlation analysis, principal component analysis and cluster analysis. A normal distribution at six traits related to fiber yield was observed, with the variation coefficients ranged from 16.33% to 69.00%. The maximum variation coefficient (69.00%) for dry fiber yield was observed in June 2020. Except variation of stem diameter was detected with the minimum coefficient (16.33%) in August 2020, the coefficient of variation of dry fiber yield, fresh bark weight, stem bark thickness, stem length and bast stripping percentage were all higher than 20%, indicating that 298 ramie germplasm resources had rich genetic diversity. Correlation analysis showed that stem length positively correlates with all the other traits. The positive correlation of stem diameter and stem bark thickness in comparison with fresh bark weight and dry fiber yield was detected, and significant positive correlation between fresh bark weight and dry fiber yield was detected, and significant positive correlation on dry fiber yield and bast stripping percentage was detected. The improvement of stem length and dry fiber yield correlates with bast stripping percentage. Principal component analysis revealed two components with the cumulative contribution rate of 82.38%, 71.01% and 79.25% at three seasons. The dry fiber yield had the greatest effect, and the bast stripping percentage had the second greatest effect, indicating that both traits could be used as important indicator to evaluate whether the ramie germplasm resource fiber yield traits were excellent. Cluster analysis suggested three groups in each season, and the 6 traits of groupⅠwere all excellent. This study identified 14 high-quality varieties such as 7469, J0501-307, Chuanzhu10, TG5, Donganyuanma 294, Xinyangma, and Guangxihongjianma, as candidate parents or core germplasm in breeding.