Studies On Evaluation For Germplasm And Construction Of Core Collection Of Vernicia Fordii In Sichuan And Chongqing Area

On the basis of the comprehensive investigation of Vernicia fordii resources in Sichuan and Chongqing area,materials were collected according to two levels(inter and intra populations),this study researched phenotypic diversity of fructification and seed of Vernicia fordii(VF)and Vernicia montana(VM) by method of mathematical statistics about16populations,a preliminary core collection was established.And comprehensively evaluating the germplasm resources of Vernicia fordii which is order to provide theoretical bases for breeding an germplasm conservation.The main results are as follows:(1) There are different degrees of variation in phenotypic character of VF inter-population and intra-population,with the range from7.89%to28.54%,morphological variation of fructification was higher than the seed,coefficient of variation(CV) of fructification weight,pericarp thick,single seed weight,total weight,seed ratio were larger,which showed that these characters are easy to influence by the environment and the heredity are unstable relatively.VM had higher variation in morphological trait of fructification,weight trait,seed ratio than VF,but VF had higher seed morphological variation.Compared with VF,VM has these traits:fructification was heavier and larger,pericarp was thicker,seed number was less,single seed was heavier,seed was flatter,seed ratio was lower among14phenotypic traits.Through the correlation analysis and principal component analysis between each phenotypic traits in VF and VM populations,the result showed that the key traits of VF were the ratio of seed length and width diameter,fructification width diameter,total weight of seed,total weight of fructification.The key traits of VM were pericarp thick,narrow diameter of seed,the ratio of seed length and width diameter,width diameter of seed.(2) VF and VM inter-population had abundant variation,and population of Wanzhou and Xiushan were better in general,which can be regarded as important object of future study.The repeatability of phenotypic traits was low inter and intra population of two kinds,which demonstrated the two kinds were more subject to the influence of environment,and the main impact-factor were altitude,temperature,water.(3) VF and VM population had high genetic diversity among populations.The phenotypic differentiation coefficient of VM was range from6.43%to74.93%,with the average of25.74%,which showed that variation intra-population(74.26%) was higher than that of inter-population.The phenotypic differentiation coefficient of VM was range from4.94%to82.74%, with the average of34.36%,which showed that variation intra-population(65.64%) was higher than that of inter-population.So the variation intra-population was the main source of variation.(4) According to UPGMA cluster analysis by Euclidean distance inter-population,12VF populations could be classified to four categories.The population of Pingchang,Chaotian,Wanyuan,Yanyuan,Huidong clustered together.Fuling was a class by oneself,Wanzhou and Xiushan force together as a class,Zitong,Qionglai.Rongxian,Meigu were a class;About VM populations,Chongzhou and Luxian clustered together,Renshou and Weiyuan force together as a class.(5) Based on the data of phenotypic diversity of populations,the300parts of VF germplasm materials were studied by group clustering method,5candidates (30%,25%,20%,15%,10%)were collected and compared the genetic diversity index,tested significance of difference,60parts of core collection was established under20%of the sampling rate.Though testing the characteristic value coincidence of core collection,the mean compliance rate,the standard deviations rate,the coefficient of variation were98.07%,94.12%,95.70%,it showed that the primary core collection were able to represent genetic variation of total germplasm.