Main quality chemical components of 65 new tea plant strains in Damiao Mountain of Guangxi

【Objective】To identify 65 new tea plant strains in the Damiao Mountain area of Guangxi,analyze their quality chemical composition characteristics and suitability,and lay the scientific foundation for cultivating new tea plant varieties with local characteristics.【Method】The 65 new tea plant strains bred by germplasm resources in Damiao Mountain of Guangxi were as objects. The main quality chemical components were determined and analyzed by conventional biochemical analysis and high performance liquid chromatography(HPLC) ;their Shannon-Weaver diversity index(H') was analyzed by statistical software,and principal component analysis,cluster analysis,correlation analysis and suitability analysis were conducted. Finally,the tea plant strains with excellent germplasm resource potential were screened.【Result】The diversity indexes of 65 new tea plant strains ranged from 1.45 to 2.07,with an average of 1.88,and the coefficients of variation ranged from 17.37% to 97.70%,with an average of 36.75%,showing a rich genetic variation. The 65 new tea plant strains were clustered based on quality chemical components determination,and at a genetic distance of 14.5,they could be divided into six taxa,with taxon Ⅰ containing 45 strains,taxon Ⅱ containing 9 strains,taxon Ⅲ containing 7 strains,taxon Ⅳ containing 1 strain,taxon Ⅴ containing 2 strains,taxon Ⅳ containing 1 and taxon Ⅵ containing 1 strain.The correlation analysis of the 15 chemical components and indexes of the 65 new tea plant strains showed that there were 12 pairs of significant positive correlations,5 pairs of significant negative correlations,34 pairs of highly significant positive correlations and 14 pairs of highly significant negative correlations. Principal component analysis was performed on the 15 chemical components and indexes,and 4 principal components were extracted with a cumulative contribution of variance of 80.80%. Among the 65 new tea plant strains,55 new tea plant strains were suitable for green tea production,and 10 were suitable for both red tea and green tea,and 16 were germplasm resources with excellent germplasm potential.【Conclusion】The 65 new tea plant strains in the Damiao Mountain area of Guangxi have rich diversity of quality chemical components and obvious genetic variation,and have the potential to cultivate excellent new tea plant varieties.