Establishment of primary core collection of Chinese plum（Prunus salicina） by improved least distance stepwise sampling strategy

Abstract：The core collection is useful to improve the efficiency of crop germplasm conservation,evaluation and utilization.In order to characterize and utilize the germplasm more efficiently for further plum improvement,total of 405 accessions of Chinese plum（Prunus Salicina Lindl.） germplasm maitained in the Xiongyue National Germplasm Repository for Plums and Apricots were used for establishing the primary core collection of Chinese plum based on the diversity of 46 morphological and agronomic traits.The primary core collection consisting of 97 accessions,accounting for 24% of the whole collection,were randomly sampled based on Improved Least Distance Stepwise Sampling strategy（ILDSS） form whole collection accessions.The genetic diversity of primary core collection were compared with the whole collection,which showed that the genetic variation in the whole collection was well presented in the primary core collection based on comparison of diversity index of the involved traits.Additionally,average percentage of polymorphic loci,average Nei＇s genetic diversity,average Shannon＇s information index,coincidence rate of range,variable rate of coefficient of variation,mean difference percentage,variation difference percentage and the principal component analysis（Scatter diagram） were the effective parameters which could be used to evaluate the diversity and representative of core collection.