| Recent table grape (Vitis viniferaL.) breeding emphasis all over countrys around the world is clearly geared toward early ripening and seedless grape cultivars. In-ovulo embryo rescue provides an attractive alternative to conventional methods of breeding for seedless and early ripening grapes by allowing recovery of progenies from abortive ovules of the hybrids resulting from seedless and early ripening grapes as female parents and from cross between the diploid and tetraploid grape cultivars. This technique has made a great promotion to the breeding efficiency of seedless and early ripening grapes. Thus, the embryo rescue technique plays an important role in shortening breeding cycle and accelerating the breeding progress of table grape cultivars.This study was carried on the in-ovulo embryo rescue culture resulting from hybridization not only between seedless grapes, early ripening grapes as female parents and late ripening grapes as male parents with better characters, eg, big berries and enduring storage and transportation, but also between diploid and tetraploid cultivars. The result indicated that the average numbers of normally developed ovules in every berry decreased with its growth and development. There was significant difference in developing trend of berries among different crosses. A great number of ovules began to abort 20d after artificial pollination, and increasingly abort 45d after artificial pollination. So, in-ovulo embryo rescue culture of aborted ovules was desirable 45d after pollination.NN-1969 as basal medium for in-ovulo embryo rescue culture was more optimized than MS and B5 medium. Ovule calli were produced less and the average calli rate was under 24%, as well as the average normally developing ovule over 90%. This indicated that the low concentration of inorganic salts were more beneficial to the development of young ovules than high concentration of inorganic salts. On the medium of NN-1969+1AA 1.75 mg.L"1 -KjA30.35mg.L~1, the average in vitro germination rate of hybrid ovule was the highest, up to 52.80 %. When those ovules germinating normally with freshly green cotyledons were transferred to 1/2MS medium plus none plant hormones, the average rate of growing-into seedlings was the highest, up to 35.42%. Interestingly, 13.33% of the hybrid embryos from Pheonix SIX Red globe firstly produced albino seedlings. After those ovules from Sam seedlessXRed globe cultured on NN-1969 + 2, 4-D 0.05mg.L~'+6-BA 1.0 mg.L'1 were geminated in vitro, and then, transferred to 1/2MS medium plus none plant hormones, 14.28% of germinated embryos produced white, egg-shaped and cluster embryoids maintaining in culture of secondary embryogenesis in the transition zone between the hypocotyl and the root. And, those embryoids easily germinated and grew into seedlings on1/2MS medium plus none plant hormones.Lower concentration of sucrose was beneficial to the development of young embryos. The concentration of sucrose optimized to in-ovulo embryo rescue culture was SOg.L"1. In this case, the in vitro germination rate and the growing-into seedling rate of hybrid embryos from Sam seedlessXRed globe and Jingxiu XKyoho were the highest, up to 39.28%, 35.71%, 19.23% and 7.69%, individually.Sclerosesed integuments of grape ovules usually blocked the germination of embryos in embryo rescue culture. If those ovules were cutted into halves and cultured the micropylar halves on the optimized medium, rates of the in vitro germination and the growing-into seedling of embryos were efficiently promoted. In this study, two kind of rates of hybrid embryos from Fujiminori X Jingxiu increased 15.74% and 15.91%,individually, by applying this method as compared to by directly culturing intact ovule.The presence of activated charcoal (AC) with the optimized concentration had efficiently reduced the browning of ovules and medium during in-ovulo embryo rescue culture. 2g.L"'AC was better than that of 0 g.L"1, 1 g.L"1 and 4 g.L"'. And, rates of the in vitro germination and the growing-into seedling of embryos fro...
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