Genetic Diversity Of Wild Actinidia Eriantha Benth Germplasm And Association Analysis Between AsA Content And SSR Markers

The germplasm resources of Actinidia eriantha Benth in Wu Gong Mountain were investigated. The genetic diversity and genetic relationship of 70 A. eriantha Benth germplasm were evaluated by fruit traits and SSR markers. The ascorbic acid (AsA) contents were determined and analyzed, and found the excellent kiwifruit germplasm based on the studies. It could provide the theoretical basis for the available development and utilization of wild kiwifruit resources and the accumulation mechanism of AsA content. By using variation analysis and association analysis method to detect the AsA contents of leaves and fruits in wild population natural variation and association analysis of SSR markers, for exploring wild A. eriantha Benth excellent genes and genetic improvement.The results were as follows:1、Genetic diversity of wild A. eriantha Benth germplasm based on fruit traits and SSR markersAccording to the published UPOV kiwifruit belong to breed standard on the germplasms fruit phenotypic traits. Reference to kiwifruit genetic linkage map, choose distributed in kiwifruit genome of 70 pairs of SRR primers were used for material for genetic diversity analysis. The collected 70 accessions have rich genetic variation in both fruit traits and SSR markers. Fruit Traits of UPGMA cluster analysis separated 70 accessions into the circular and elliptic group, elliptic group and the oblong group.21 SSR primers produced 127 bands and the Genetic similarity based on SSR markers ranged from 0.5306 to 0.9252,with an average of 0.7805.The polymorphic bands accounted for 100% of the total bands. GS values at the 0.65 level, UPGMA cluster analysis separated 70 accessions into third major groups. The circular fruit, the elliptic fruit and the oblong fruit of accessions in A. eriantha Benth would be clustered preferentially related to their fruit traits. A significant though moderate correlation was observed between fruit traits of UPGMA cluster analysis and SSR marker UPGMA cluster analysis.2、A mutation analysis of ascorbic acid content in the leaves and fruit of wild A. eriantha BenthThe AsA contents of wild kiwifruit leaves and fruits existed rich variations, the variation coefficient of AsA content of leaves was 41.30%, and the variation coefficient of AsA content of fruits reached 21.88%. Based on the mature leaves and young fruits AsA content distribution of frequency analysis, the mature leaf AsA content are mainly concentrated in 1.00～2.75 mg·g-1 FW, accounting for 77% of the total, the young fruit AsA content are mainly concentrated in 10.00～17.00 mg·g-1 FW, the distribution frequency is 80%. By the mutation analysis and variance analysis, eight wild excellent kiwifruit germplasms of high AsA content were screened(No.9、35、15、56、57、14、7、 27).Eight high fruit AsA content fruits of excellent germplasm AsA content are above 17.00 mg·g-1 FW, of which No.9 species highest (21.27 mg· g-1 FW); Single fruit quality in more than 6.35 g; Soluble solids in more than 5.77%; Soluble sugar minimum is 0.72%; Titratable acid in more than 0.73%3、Leaf and fruit AsA content natural Variation and association analysis using SSR markers in wild A. eriantha BenthSevevty different wild genotypes of leaves and fruits randomly collected from A. eriantha Benth germplasm resources in Wugong Mountain of Jiangxi province and with its young leaves genomic DNA as a template, A total of 21 SSR markers were screened for populations materials and population structure analysis, then association analysis between SSR markers and AsA contents were performed using TASSEL GLM (General Linear Model) and MLM (Mixed Linear Model) programs. The results indicated that the AsA contents of wild A. eriantha Benth leaves and fruits existed rich variations. Genetic structure analysis showed that the population of these materials was composed of 4 subpopulations. At P< 0.01 level, there were 7 SSR markers associated with the leaf and fruit AsA content under GLM program, and the rate of explanation on the phenotype of related marker ranged from 0.0825 to 0.1755. There were 6 SSR markers associated with the leaf and fruit AsA content under MLM program, and the rate of explanation on the phenotype of related marker ranged from 0.0736 to 0.1546. Variation analysis and population structure of 70 materials were analyzed through SSR markers and their association with AsA content were detected. Seven markers, associated with the leaf and fruit AsA content were determined under GLM program. And 6 markers associated with the leaf and fruit AsA content were determined under MLM program.