滇型杂交水稻不育系花粉败育特征及其稳定性研究

Studies on the Characteristics of Pollen Abortion and Its Stability in CMS Lines of Dian-Type Hybrid Rice

本研究结果表明:籼稻D_4珍汕97A花粉败育发生在单核期,其余粳稻不育系花粉败育发生在双核至三核期。败育原因在于花粉发育过程中的第二次分化发生障碍,导致发育缓慢,到开花期仍不能成熟而表现败育。不育系花粉母细胞减数分裂基本正常。不同核质互作类型的不育系,花粉败育特征和败育程度有所不同,可分为4组:1组,X黎明A;2组,D_1、D_3黎明A和科情三号A;3组,D_1、D_8滇榆一号A和D_4、D_9科情三号A;4组,D_4珍汕97A。1,2组的不育系花粉败育程度较轻,易受环境条件影响而表现出不育性不稳定,出现少量自交结实现象。就细胞质的遗传效应而言,X型与D型相差明显,D_1和D_3型相似;X、D_1和D_3型不育性较不稳定,D_4、D_8和D_9型不育性较稳定。

The pollens of No. 97 Zhenshan of Dian-type4 (Oryza sativa L. subsp. indica) abort when they are in the single-nucleus stage, while those of other CMS lines (Oryza sativa L. subsp, japonica) in the two to three nuclei stages. The pollen abortion is attributed to obstruction during the second differentiation of pollen, causing poor development and failure to maturell when the flowering stage of the rice comes. However, among the CMS lines with different cytoplasms and/or nuclei, variations can be found in the characteristics and degree of pollen abortion, according to which, all CMS lines in the experiment were classified into 4 groups: group Ⅰ, Liming CMS line of Xing-type; group Ⅱ, Liming CMS lines of Dian-typel and Dian-type3, No. 3 Keqing CMS line of Dian-type3; group Ⅲ, No. 1 Dianyu CMS lines of Dian-type1 and Dian-type8, No. 3 Keqing CMS lines of Dian-type4 and Dian-type9, (the above are japonica); group Ⅳ, No. 97 Zhenshan CMS line of Dian-type4. Group Ⅰ, Ⅱ are not stable enough in their male sterility due to their slight pollen abortion and thus sensitive to the environmental conditions such as higher atmospheric temperature. Seed setting produced by self-pollination, though very small, happened in 3 CMS lines to group Ⅰ, Ⅱ. As far as genetic effects of cytoplasm are concerned Xing-type varies with Dian-type, Dian-type1 is similar to Dian-type3. Compared with this three, Dian-type4, Dian-type8 and Dian-type9 have a more stable cytoplasmic effect on male sterility.