Selection of superior provenances/families of Docynia delavayi based on phenotypic variation analysis on seedling growth traits

Docynia delavayi (Franch.) Schneid. is a wild fruit tree that can be widely used for medicinal and edible purpose and has a high value of exploitation and utilization. We analyzed the growth traits of 62 half-sib families from 10 provenances in order to acquire more information about the genetic variance of growth traits in D. delavayi. Variation analysis, correlation analysis, principal component analysis, estimation of genetic parameters and comprehensive analysis were all done based on the data on growth traits. The results of the variance analysis revealed that all traits, with the exception of branch length, differed significantly or extremely significantly between provenances, whereas only leaf length did not differ significantly between families. The results of the correlation analysis showed that all growth traits, except for branch length and petiole length, had a significant or extremely significant correlation with the geo-climatic factors. Three principal components were extracted by principal component analysis; they were used as indicators for the comprehensive evaluation of D. delavayi from different provenances, and five excellent provenances were selected: Lancang (LC), Lianghe (LH), Shidian (SD), Yingjiang (YJ) and Xiangyun (XY). The results of genetic parameter estimation showed that all indicators except leaf length and leaf width had a high potential for genetic improvement. Therefore, five traits (seedling height (SH), ground diameter (GD), branch length (BL), petiole length (PL) and the total number of leaves (TNL)) were used as comprehensive index to select superior families, and a total of 20 superior families were selected. This study will lay a theoretical foundation and practical guidance for the genetic improvement of D. delavayi.