Establishment Of Genetic Improvement Technical System For Astringent Persimmon(Diospyros Kaki Thunb.) Cultivars To Become Non-Astringent

Recent surveys in China found several native PCNA cultivars in Hubei, Henan and anhui provinces, within trait of natural loss of astringency and its alleles are dominant. The use of Chinese cultivars offers a new strategy for persimmon breeding by overcoming inbreeding depression, and has the potential for progressing the breeding of new PCNA cultivars. In this study, new F1of hybridization germplasm were obtained by artificial hybridizing pollination methods and embryo rescue techniques in corss-breeding with’Gongcheng-shuishi’and’Eshi No.1’(Diospyros kaki Thunb) as female parents; and Male strain No.10(Diospyros kaki Thunb), which is staminate Diospyros spp. germplasms as male parents. The techniques of tissue culture, transplanting, tip grafting in vivo by using in vitro plantlets were applied for the preservation of new germplasm. Parentage of breeding populations was identified by SSR and IRAP markers, which have been developed in Oriental persimmon. Moreover, RO2-SCAR marker was chosed for marker-assisted selection with the non-astringent trait.The major results are indicated as follows:1. The hybridization tests indicated that, the pollen germination rate of the Male strain No.10was29.9%, as to the normal germination ability. It also exhibited a high affinity with’Eshi No. l’or’Gongcheng-shuishi’, and the fruit set percentage of the two hybridized combinations was66.7%and40.0%. We got251plantlets based on the mechanism of embryo culture, including162offspring of’Gongcheng-shuishi’xMale strain No.10and89offspring of’Eshi No.1’xMale strain No.10, which germination rates was94.7%and95.8%, respectively.2. Due to using the techniques as in vitro culture, transplanting, tip grafting in vivo by using in vitro plantlets, there were348plants was preservated. The number by using in vitro culture for the preservation was237, transplanting was108, and graft was3. The breeding plants were derived from embryo culture in vitro on summer, and it can be used as scions grafted on1-2years seedings or juvenile vine of Diospyros spp. plants.3. In SSR analysis, two primer pairs were screened out to identify the hybrids F1populations (’Huashi No.1’×Male strain No.10) within6samples, and one primer pair for identification of heterozygosis of the other populations’Huashi No.1’×’Luotian-tianshi’including32samples. Identification of parentage of breeding populations (’Huashi No.1’×Male strain No.10) by IRAP markers showed the5early-flowering plants, which were grafted two years ago, were originated from a same embryo culture plant. Forty-six of cross breeding populations (’Eshi No.1’×Male strain No.10) were considered as PCNA type through RO2-SCAR marker determination.