杂交粳稻亲本米质性状优异配合力的标记基因型鉴定

杂交粳稻米质整体水平不如常规粳稻也是限制杂交粳稻广泛种植的原因之一。本研究选用115个SSR引物扩增6个粳稻BT型不育系和12个恢复系的标记基因型，并分析72个F₁组合谷粒长、谷粒宽、糙米率、精米率、整精米率、垩白米率、垩白度、糊化温度、胶稠度和直链淀粉含量10个米质性状的配合力，结合亲本SSR分子标记数据和性状配合力数据筛选了10个米质性状优异配合力的标记基因型。结果共鉴定出30个SSR标记基因型与亲本10个米质性状配合力显著相关，其中25个与亲本米质性状不良配合力相关，5个与优异配合力相关。标记基因型RM263-175/180和RM444-230/240可以使F₁整精米率分别提高3.2%和2.5%。RM3-120/150可以使F₁谷粒长缩短2.4%，RM444-180/240可以使F₁谷粒宽增加2.1%。RM428-273/294可以使F₁植株上的杂交稻米直链淀粉含量减少7.0%。有8个标记基因型同时也影响产量性状配合力。RM3-120/150同时可以使F₁的每穗总粒数和每穗实粒数分别增加15.9%和10.9%。RM1211-150/160可使F₁的糙米率和精米率分别减少0.9%和1.1%，同时使F₁的每穗总粒数和每穗实粒数分别增加21.8.%和20.4%。RM23-150/160可使F₁的垩白米粒率和垩白度分别增加44.1%和45.7%，同时使F₁的单株日产量和每穗总粒数分别增加11.2%和11.6%。这些结果可用于指导亲本米质性状和产量性状配合力的分子标记辅助改良以及未来杂交粳稻组合配置中的亲本选配。

Identification of Marker Genotypes Associated with Elite Combining Ability for Quality Traits in Parents of Hybrid Japonica Rice(Oryza sativa L.)

The area planting japonica hybrid rice is only 3% of the total area (8.28´10⁶ ha) of japonica rice. One of the reasons why japonica hybrid rice popularized slowly is that grain quality of hybrid was inferior to that of conventional cultivars. In order to improve grain quality combining ability of parental lines more efficiently, SSR marker genotypes of elite combining ability for 10 quality traits, namely, brown rice rate (BRR), milled rice rate (MRR), head rice rate (HRR), grain length (GL), grain width (GW), percentage of chalky grain (PCG), chalkiness degree (CD), gelatinization temperature (GT), gel consistency (GC) and amylose contents (AC), were identified in this study, by analyzing the data of combining ability and SSR markers in six CMS lines and twelve restorer lines, which were genotyped using 115 pairs of SSR primers. A total of 30 SSR marker genotypes were significantly associated with combining ability of the 10 quality traits. Twenty-five of them were marker genotypes for unfavorable combining ability of quality traits. The remaining five marker genotypes were associated with elite combining ability for quality traits of parents. RM263-175/180 and RM444-230/240 were marker genotypes of elite combining ability for HRR, which increased 3.2% and 2.5% of HRR in F₁, respectively. RM3-120/150 shortened GL value in F₁ by 2.4%. RM444-180/240 increased GW trait value of F₁ by 2.1%. RM428-273/294 decreased AC trait value of hybrid rice harvested from F₁ plants by 7.0%. Among the SSR marker genotypes associated with combining ability of the 10 quality traits, eight marker genotypes also affected combining ability of yield components simultaneously. RM3-120/150 increased simultaneously total spikelets per plant (TSP) and filled spikelets per plant (FSP) in F₁ by 15.9% and 10.9%, respectively. RM1211-150/160 decreased trait values of BRR and MRR in F₁ by 0.9% and 1.1%, respectively, and simultaneously increased trait values of TSP and FSP in F₁ by 21.8% and 20.4%.RM23-150/160 increased trait values of PCG and CD in F₁ by 44.1% and 45.7%, and simultaneously increased daily yield per plant and TSP in F₁ by 11.2% and 11.6%, respectively. These results could be used for directing improvement of combining ability of parents for quality traits and yield traits through the marker-assisted selection, and for determining parents for making combinations of hybrid japonica rice in the future.