Early Screening Of Natural Deastringency Trait And Cross Breeding In Chinese Pollination Constant Non-Astringent Persimmon

There is abundant persimmon(Diospyros kaki Thunb.) cultivars existing in China and natural variation provide plenty of material for cross-breeding research. There are two main obstacles in persimmon genetic improvement, one is the high ploidy and the other one is fewer staminate germplasm. In the present study, on the basis of the analyzing the parents combination of Chinese PCNA cross breeding, we focused on the early screening of natural deastringency trait. In addition, we investigated the identification and genetic relationships among some persimmon cultivar by SCoT, hoping provided a scientific basis for Chinese PCNA genetic improvement. The main results were as follows:1. A total of154bands were generated by17informative SCoT primers screened from36SCoT primers in34Diospyros spp. The polymorphic rate of SCoT markers was94.16%, and the average number of polymorphisms was8.5. The result of clustering analysis using UPGMA and PCoA showed that the34genotypes could be divided into3Clusters. The first cluster included the persimmon local cultivar from Jiangxi province, while the second consisted of other persimmon cultivar.. Oil persimmon, Chekiang persimmon and Jinzaoshi formed the third group. PCNA can be separated from non-PCNA, and PCNA originated from Japan and China was distinguished. Cluster analysis of SCoT markers through the UPGMA and PCoA analysis were largely consistent.2. Eight Diospyros spp. staminate germplasm materials were used to test they pollen germinability in vitro. The results showed that the pollen germinability in vitro of those materials from16.8%to64.2%. The pollen germinability between Chinese androecious genotypes and common pollination cultivar ’Zenjimaru’ and ’Nishimura-wase’ were equal. There was not much difference about the pollen germinability in a same genotype at different years. Fruit setting rate was impacted greatly by maternal. There was no relevant between affinity index and fruit setting rate. The parthenocarpic ability could impact the affinity index.3. The astringency type of Chinese PCNA persimmon can not be identified throughout Mast/MAST genotyping; the RO2marker was detected in ten Chinese PCNA types and six androecious genotypes from44persimmon cultivars, but not in any of the non-PNCA and Japanese PCNA types.This indicated that the RO2maybe linked to the allele associated with the non-astringent trait of the Chinese PCNA types. The segregation behavior of RO2in both Fi populations was consistent with a1:1ratio, suggesting the non-astringent trait of Chinese PCNA types is controlled by a single domiant gene locus. The presence of the RO2marker among androecious material indicates that they also have potential as donor of non-astringency trait of Chinese PCNA type.In summary, the most valueable combinations of Chinese PCNA cross breeding maybe from ’Eshi No.l’,’Gongcheng-shuishi’,’Huashi No.l’crossing with’Luotian-tianshi’and Chinese androecious genotypes respectively. Compared to persimmon breeding program in NIFTS, there are two advantage in genetic improvement system of Chinese PCNA persimmon, one is avoiding inbreed depress, and the other one is improving the efficiency of PCNA breeding.