Genetic Diversity Analysis Of New White Pulp Loquat Cultivar ’Huabai No.1’ Seeding Offsprings Population

As a plant in Eriobotrya （Rosaceae）, Loquat（Eriobotrya japonica Lindl.） is native to southwest in China. It is a kind of self-pollination and cross-pollination fruit tree. Loquat fruit generally divided into two categories:red sarcocarp and white sarcocarp. White sarcocarp is a treasure with thin skin, tender flesh and sweet taste.’Huabai No.1’ were good individual loquat trees, they were screened out from seeding offspring of famous’Ruitiaobaisha’ and was identified as a new loquat cultivar （Identification Number:2014011） in Chongqing.The sarcocarp was fine and smooth, the fruit juice was sweet, the carbohydrate content was high but the acid content was low, the yield was greet, the fruit was big and matured early. The quality of fruit was better than’Ruitiaobaisha’. A part of’Huabai No.1’ seeding offsprings started to bear fruit which had different color obviously. The fruit biological characters of ’Ruitiaobaisha’ seeding offsprings were analyzed in order to explore the reason of the color difference. Genetic diversity analysis of all’Ruitiaobaisha’seeding offsprings, the female parent and candidate male parents evaluated the level of genetic diversity and the relationship.The result showed:1. This paper investigated and analyzed fruit biological traits of48seeding offsprings by using principal component analysis, factor analysis and cluster analysis. The results showed that:9characters of the fruit were divided into3components by the principal component analysis. The average weight, the maximum weight and the transverse diameter were the first principal component. The second one included color of pericarp, the color of sarcocarp, the fruit shape index and the longitudinal diameter. The modality of fruit ventricular and the soluble solids content were third component. The cumulative contribution rate of three components was82.965%. The clustering of48seeding offsprings based on Pearson Correlation Coefficient, the result showed obviously different plants could be ditinguished.2. This paper analyzed the quality of48offsprings and1female parent, including the average weight, the maximum weight, color of pericarp and sarcocarp and total soluble solids content. The factor score was based on the formula which was FAC11×38.810%+FAC2₁×38.482%. The score of female parent was0.1113, it bellowed the scores of26offsprings. The score of H22-3was the highest score, it was0.7342and the score of H15-9was the lowest, it was-1.5044.3.23high-polymorphism SSR primers were screened out in the study. The primers Hi04e04can identify triploid of A35by amplifying235bp,227bp and211bp alleles. There were63alleles amplified by23pairs SSR primer in the seeding offsprings. The result showed that each pair of primers amplified2.74alleles averagely, mean effective number of alleles was1.80, mean observed heterozygosity was0.24, mean expected heterozygosity was0.39, mean fixation index was0.54, mean polymorphic information content was0.35.4. The amplification results of SSR molecular markers on seeding offsprings were analysed by NTSYsPc-2.10and the dendrogram was formed by UPGMA. All germplasms were divided into3groups at0.676（similarity coefficient）, and the Ⅱ categorie were divided into4groups at0.739further. H25-1was alone in the cluster and its soluble solids content was the largest in all offsrings with fruit.5. Compared the two dendrograms based on loquat morphology and SSR, two kinds of clustering results could differentiated offsprings well according to the fruit color. The results of two clusterings have a certain consistency.6. This study analyzed the candidate male parents of190seeding offsprings by CERVUS.When the confidence level was above95%, male parents of8offsprings could be certained; When the confidence level was above80%, a total of7male parents could be confirmed, they crossed with the femal parent generated20Offsprings, the number of these offsprings ranged1to3beside10offsprings generated by E2428. Other170offsprings generated by the female parent’s self-pollination, the rate was89.47%.