平邑甜茶外源花粉授粉效果和生殖机能研究

Study on Pollination Effect and Reproductive Function of Malus hupehensis with Foreign Pollen

以平邑甜茶(Malus hupehensis)为母本,用"红丽"观赏海棠花粉进行人工授粉,设计不去雄不授粉不套袋、去雄授粉套袋、套袋花开后去雄授粉和去雄不授粉套袋四个处理,利用物理统计、显微观察、流式细胞仪等技术,研究不同授粉处理平邑甜茶坐果率、果实生理性状、后代实生苗杂种率和倍性的差异,进一步探索平邑甜茶的生殖机能,选择出平邑甜茶杂交率较高的时期以增加平邑甜茶的杂交率和杂交种子数,扩大选择范围,提高育种效率,为育种实践提供重要的理论依据。结果显示,经授粉处理后,平邑甜茶种子千粒重增加约8.7%;坐果率显著提高,10月时相比自然授粉状态下提高约10.1%。自然状态下平邑甜茶无融合生殖率约为43.70%,各处理杂交后代实生苗大部分为三倍体,少数为二倍体、四倍体、五倍体和非整倍体,且花开前去雄授粉套袋处理显著提高四倍体形成率。综上所述,人工授粉有助于提高坐果率,促进种子形成;平邑甜茶以无融合生殖为主,同时也进行有性杂交,且花开前授粉能显著提高四倍体形成率。但三倍体后代实生苗是经有性生殖还是无融合生殖产生,需进一步鉴定。

Malus hupehensis was used as the female parent,and was artificially pollinated the pollen of Hongli ornamental crabapple. Four treatments including no emasculation and pollination with no bagging( T1),emasculation and pollination with bagging( T2),emasculation and pollination after flowering with bagging( T3),emasculation and no pollination with bagging( T4) were conducted to research the differences in fruit setting rate,fruit physiological traits,offspring seedling hybrid rate and ploidy of Malus hupehensis by physical statistics,microscopic observation and flow cytometry. This study was aimed at further exploring the reproductive function of Malus hupehensis,selecting the period for high hybridization rate to increase the hybridization rate and the number of hybrid seeds,expanding the selection range,improving the breeding efficiency and providing important theoretical bases for breeding. The results showed that the seed weight increased by 8. 7% after pollination; the fruit setting rate significantly increased by 10. 1% compared with the natural pollination in October. The apomixes rate of Malus hupehensis was about 43. 70%. Most of the hybrid offspring seedlings of the four treatments were triploid,and the diploid,tetraploid,pentaploid and aneuploidywere less. The tetraploid formation rate increased significantly under emasculation,pollination and bagging before flowering. In conclusion,artificial pollination was benefit for improving the fruit setting rate and promoting the seed formation. Malus hupehensis used apomixes as the main reproductive mode,and also had sexual hybridization. Pollination before flowering significantly increased the tetraploid formation rate. But it needed to be further identified that the reproductive mode of triploid offspring seedlings was sexual reproduction or apomixes.