The Hybridization Of Fraxinus Mandshurica×Fraxinus Velutina And The Establishment Of F1 Embryo Culture System And The F1 Salinity Tolerance

First, we hybridized Fraxinus mandshurica on different age of productive phase from two different provenaces (DaiLing, WeiHe) as female parent, and Fraxinus velutina from different provenaces (PanJin, TianJin) as male parent in which pollen were treated through high voltage static field. Then the in vitro culture system of two kinds of zygotic embryos in F. velutina and hybrid ones harvested were established. At last, we analyzed the growth of F1 hybrid seedlings and calli under the stress of NaCl. The results were as follows:1,In the seed setting in female trees hybrided, there was remarkably distinct between the pollen treated and ones untreated by high voltage static field, between female parent provenances and not prominent between male parent provenances. The seed setting also was influenced by the high voltage static field and the age of parent tree. The order of their seed setting was fastigium of productive phase＞productive phase＞early productive phase.2,The characters of hybrid seed-wing length, wing wildth and 1000-seed weight, were closer to female parent (F mandshurica), in which there was significantly different between female parent provenances, and not remarkable discrepancy between male parent provenaces.3,The 100% of F. velutina zygotic embryo germinated into seedling in the MS medium without any plant grow regulator. When this species was proliferated in vitro through above shoots obtained, the optimum condition was MS+BA4.0mg/L +NAA2.0mg/L, and the induction rate was 39.29%, proliferation index 3.59. The optimum rooting condition of shoot was 1/2MS+IBA1.5 mg/L, the highest rooting rate 65.80%.4,Hybrid zygotic embryo germinated into seedling after 4 days of culture in WPM medium. The best condition of the axillary bud induction was MS+ TDZ0.1mg/L+NAA3.0 mg/L, the highest rate of axillary bud induction was 77.00%. The optimum condition of shoot rooting was 1/2MS+IBA1.0 mg/L+NAA0.1mg/L, and the highest rooting rate was 61.90%. When the callus induction was conducted from the root segment of hybrid seedling, the best condition was MS+BA4.0mg/L +NAA2.0mg/L, with the highest callus induction rate of 81.16% after the dark culture for 48h and the light culture for 7 days.5,The results of F1 hybrid seedlings treated with different concentration of NaCl showed that the half death concentration for them was 0.2 mol/L. Then different provenance hybrid seedlings and calli were treated in the half death concentration of NaCl, and the ones of F. mandshurica (DaiLing)×F. velutina (PanJin )were the better in the salinity tolerance.