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The purpose of this study was to understand factors affecting in vitro embryo rescue culture from hybrids between diploid and tetraploid varieties of grape in creation new triploid germplasm resources. The effects of different media, removal ages of immature seeds and reciprocal crosses of parents on the germination and seedling survival of immature seeds from crosses between diploid and tetraploid grape varieties by in vitro embryo rescue culture were investigated. The results indicated that the medium consisting of NN-1969 + IAA 1.75 mg l -1 + GA 3 0.35 mg l -1 + CH 400 mg l -1 + AC 2.0 g l -1 was better than other media. The optimal removal age of immature seeds for the best development of embryos was 35-45 days after pollination (DAP). The percentage of germination (PG) for immature seeds and the percentage of seedling survival (PSS) for immature seeds for diploid varieties used as female parents were 10.72% and 4.35% higher than when tetraploid varieties were used as female parents respectively. A total of 41 hybrid progenies from eight combinations were obtained, made up of 17 diploid, 9 tetraploid, 14 aneuploid, and 1 triploid progeny as determined by root-tip chromosome identification. The triploid progeny was from Fujiminori (2n = 4x = 76) · Jingxiu (2n = 2x = 38). These results implied that it was feasible to extend the hybridization range of grape and to create new germplasm resources by in vitro embryo rescue based on the conventional hybridization. The NN-1969 medium supplemented with GA 3 and IAA was more propitious to the development of immature seeds sampled at about 45 DAP. It was easier to obtain plants using diploid as female parent, but triploid progeny was only obtained using tetraploid as female parent.

The synchronized behaviors of a noisy small-world neuronal network with delay and diversity is numerically studied by calculating a synchronization measure and plotting firing pattern. We show that delay in the information transmission can induce fruitful synchronization transitions, including transition from phase locking to antiphase synchronization, and transition from antiphase synchronization to complete synchronization. Furthermore, the delay-induced complete synchronization can be changed by diversity, which causes the oscillatory-like transition between antiphase synchronization and complete synchronization.