杂交水稻亲本亲和性改良研究初报

目的]对广西杂交水稻亲本进行亲和性改良,使之携带广亲和基因,为水稻亚种间杂种优势利用奠定理论依据,为水稻育种提供种质资源.方法]通过杂交把强广亲和基因S5n或f5导入广西主栽杂交水稻亲本中,经过复交、回交和连续多年自交获得一批亲和性改良株系.利用籼稻和粳稻对改良株系进行亲和性鉴定.将亲和性改良株系与目前生产上常用的不育系测交,测定其育性及其配合力.结果]10份亲和性改良株系均具有广亲和性,其中NL3和NL4属于广亲和保持株系,NL1、NL2、NL5和NL7属于广亲和恢复株系,NL1和NL2的恢复力较强,各个性状的一般配合力和特殊配合力效应较高.NL6、NL9和NL10对不育系盟A保持不育,但可以恢复龙特浦A、博A和广信A的育性,恢复力较弱;NL8对不育系广信A保持,但可恢复盟A、博A和龙特浦A的育性,恢复力较弱.结论]广亲和保持株系NL3和NL4可转育出广亲和不育系,广亲和恢复株系NL1和NL2可与本课题组培育的有粳稻血缘的不育系组配,有望获得杂种优势强的新组合.

Preliminary report on compatibility improvement of hybrid rice parents

【Objective】This research aimed to improve the compatibility of hybrid rice parents in Guangxi in order to obtain excellent wide compatibility genes， to provide theoretical basis for the utilization of intersubspecific heterosis in rice， and to implement germplasm resources for rice breeding. 【Method】The strong wide compatibility gene Sn5 or f5 was introduced into the Guangxi main hybrid rice cutivars’ parents through hybridization； after multiple-crossing， backcrossing， and self-crossing over consecutive years， numerous improved compatibilty strains were attained. The compatibility of improved strains was identified utilizing the indica and japonica rice lines. The fertility and combining ability of improved strains were determined by test-crossing the strains with common sterile lines during production. 【Result】From research results， 10 improved strains with wide compatibility were obtained， out of which the NL3 and NL4 lines exhibited wide compatibility maintainer line， while NL1， NL2， NL5， and NL7 exhibited wide compatibility restorer line. The restoring ability of NL1 and NL2 was relatively stronger， and the various characters observed from the general combining ability effects of the two lines were also higher. The NL6， NL9， and NL10 line exhibited sterility to sterile line Meng A， but can restore the fertility of Longtepu A， Bo A， and Guangxin A with weaker restorer ability. The NL8 line maintained the sterility of Guangxin A， but can recover the fertility of Longtepu A， Bo A， and Guangxin A with weaker restorer ability. 【Conclusion】Maintainer strains NL3 and NL4 with wide compatibility could be developed into widely compatible sterile lines and the restorer strains NL1 and NL2 with wide compatibility could be bred with the japonica CMS group， in which strong heterosis in the new combination was expected to be obtained.