| Many stone fruits, such as peach, plum, apricot, cherry et al., origined from China. There are many excellent resources in China. For example, Chinese cherry is self-fertility, but Cerasus humilis has a strong ability of drought resistence. It is important for protection and utilization of stone fruit germplasm resources to creat new germplasms and increase genetic diversity adopting distant hybridization technology. Aiming at the cross-incompatibility and hybrid sterility, this experiment has been done in fruit biology laboratory of Shandong Agriculture University, Sijiazhuang orchard, fruit breeding base of Shandong Agriculture University in Hengling, and Huama Wan orchard form 2002 to 2003. Interspecific hybridization was carried out with selecting sweet cherry 'Elton', 'Napoleon' and 'Hongdeng' as female parents and Chinese cherry 'PingDu cherry' and 'LaiYang cherry' as male parents. Different cross combinations have different setting percentage and different hybrid abortion period. Embryo rescue system of hybrids was studied and identification of them was also made. The relationship between hybrid and parents were identified by S allele-specific PCR, RAPD and morphological characteristics analysis. Many hybrids have been successfully transplanted to field, and they will offer germplasm for further breeding and research. The results showed that: 1. Setting percentage was obviously different in different cross combinations. Setting percentage was highest when 'Elton' as female parent in all cross-combinations, which was 13.92% and 17.11%. This showed that the cross-compatibility between 'Elton' and Chinese cherry was highest. However, the cross-compatibility between 'Napoleon' and Chinese cherry was lowest, which was 1.39% and 1.75%. The cross-compatibility between 'Hongdeng' and Chinese cherry was modest, which was 2.29% and 4.08%. What's more, the setting percentage was higher when 'LaiYang cherry' as male parent than 'PingDu cherry'. Setting percentage of cherry declined sharply two weeks after pollination. Pre-fertilization cross-incompatibility was the main barrier because hybrid did not develop at that time. The setting percentages of the third and the 4th week had no obvious difference in 'Elton' × Chinese cherry combination, which showed that they had distant cross-compatibility to some extent and could accomplish double fertilization. But the setting percentage declined sharply in the 5th week after pollination. The research showed there was no obvious difference between hybrid fruits and open-pollinated fruits after 4 weeks' pollination, but they occurred to abort after 5 weeks. The hybrid fruits dropped gradually, and were smaller compared with normal fruits. Embryo abortion occurred in 4th week.2. Sterilization for different minutes was made on open-pollinated sweet cherry embryos, and the results showed that: The effect of sterilization in NaClO3 for 10 minutes was better than 6 minutes. Compared with capsule-extracted embryos, embryos with capsule could also grow after low temperature treatment for a long time. But they germinated slowly in early stage. So it was necessary to extract capsule for embryo culture to some extent.3. The experiment of embryo germination and growth of different embryo age was carried out. The results showed that: embryo age had great effect on embryo culture, and the longer the embryo age, the higher the rate of germination and growth. The successful culture period for young embryo was 35 days after pollination. The germination rate could higher than 60% after being rescued. However, we couldn't succeed in rescuing those embryos after pollination 28 days. Germination rate was very low after Embryos inoculated, and they could not survive after transplant. 4. It could resist brown after added vitamin C and Ac in media. Although the former study indicated that Ac had good effect in the growth of testbube seedling, this experiment showed that: The effect of adding Ac was worse than adding vitamin C. And in the effect of resistin...
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