Comprehensive evaluation of fruit quality for premium Wangmo Castanea mollissima plants

In this study, the fruit phenotype and quality of 32 superior Wangmo Castanea mollissima plants (designated GM1 to GM32) were examined to identify the trait characteristics of different cluster groups and germplasms with excellent comprehensive performance. The goal was to provide a theoretical basis and research foundation for collecting high-quality germplasm resources and breeding superior cultivars of Wangmo C. mollissima. Ten fruit phenotypic traits and 13 quality traits were measured and analyzed in these 32 superior Wangmo C. mollissima plants. Cluster analysis and principal component analysis (PCA) were used to perform a comprehensive evaluation. Extremely significant positive correlations (P<0.01) were observed for 15 pairs of fruit phenotypic and quality traits, and significant positive correlations (P<0.05) were observed for 16 pairs of traits. Highly significant negative correlations (P<0.01) were observed for 4 pairs of fruit phenotypic and quality traits, and significant negative correlations (P<0.05) were observed for 15 pairs. The plants were divided into three groups by cluster analysis: the first group had large fruits and good fruit quality, the second group had small fruits and poor fruit quality, and the third group had medium-sized fruits with a high starch content. Four principal components were extracted from the 23 traits by PCA, contributing 76.23% of the variance. The ten plants with the highest comprehensive quality were GM32, GM31, GM29, GM1, GM8, GM17, GM10, GM30, GM3 and GM28. The results of this study provide a reference for the development and utilization of Wangmo C. mollissima germplasm resources.