Cross Breeding of Polyembryonic Varieties and Immature Embryo Rescue Culture in Citrus
In the present study, these poly-embryonic varieties including Kamei (Citrus unshiu) , Jinshuigan (C. reticulata) and Taoyecheng (C. sinensis) were used as seed parents in five cross combinations. The male parents came from Taoyecheng (Citrus sinensis), Jinshuigan (C. reticulata) and Bingtangju (C. reticulata). The pollen fertility was detected in the experiment. The results showed that the three male parents pollen were normal and their average germinating rate was 10.4％ , 13. 5％ and 9. 3％ , respectively. Every anther contained 2.4×104, 3. 7×104 and 1. 9×104 pollen grains, and the pollen viability after staining was 84.0％, 87.0％ and 77.1％. The data indicated that the three kinds of pollen had high viability and could be used as cross parent in future crossing. In the test, the highest fruit setting percentage was 15. 4％ ( Jinshuigan X Bingtangju), secondly was 11.6％ (Kamei X Taoyecheng). All cross combinations obtained some hybrid fruits and seeds. Because polyembryony decreased citrus breeding efficiency, we had a study on culture of citrus immature embryos in vitro during 90 - 110 days after pollination to obtain zygotic off-springs. The zygotic embryonic seedlings were got by separating the multi-embryoies one by one in seeds of the five combinations. Furthermore, we selected the optimum period for young embryo culture in vitro. It was found that the optimum time for embryo rescue of Kamei Satsuma (S)×Jinshuigan ponkan (P) was 105 days after pollination, and for embryo rescue of Jinshuigan ponkan (P)× Bingtangju tangerine (B) and Taoyecheng orange (T)×Jinshuigan ponkan (P), were both 95 days after pollination. Young embryos could survive on MT medium supplemented with 1.0 mg/L GA3, and the young seedlings could root after inoculated on 1/2 MT medium supplemented with 0. 5 mg/L NAA and 2％ sucrose, and the rooting rate reached above 95％. By culture of young embryos in vitro, 533 plantlets were obtained from the five cross combinations. Survival of test-tube seedling transplanting was 72. 0％ by seedling training in the closing bottle, and using the soil matrix containing humus, garden soil and sand mix by the ratio of 3∶3 ∶1, the plantlets could normally grow and survive after transplantation to the greenhouse.
Citrus Poly-embryo Cross-breeding Embryo rescue Test-tube plantletstransplanting
Wu LM Jiang YC
Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430209
国际会议
11th International Citrus Congress(第11届国际柑橘大会)
武汉
英文
368-372
2008-10-01（万方平台首次上网日期，不代表论文的发表时间）