基于不同分析策略的杂交稻米碾磨品质的分子预测

 糙米率、精米率和整精米率是决定稻米碾磨品质的重要性状，在育种中对其进行有效预测具有十分重要的意义。用9个不育系与9个恢复系及其所配制的81个双列水稻杂交组合为材料，利用有多态性的174对SSR标记筛选与F1糙米率、精米率和整精米率相关的阳性位点和增效位点，分别用二组法和三组法对F1碾磨品质性状值进行预测。结果表明：1）采用二组法，利用增效位点对糙米率、精米率和整精米的预测相关系数分别为0.553（P<0.01）、0613（P<0.01）和0.772（P<001），预测效果明显优于阳性位点；2）利用增效位点，固定不育系进行预测，3个碾磨品质性状的相关系数与显著性水平明显高于固定恢复系的结果，表明不育系对碾磨品质的影响大于恢复系；3）固定不育系时三组法预测杂交稻米糙米率、精米率和整精米率杂种优势的相关系数依次为0.466（P<0.05）、0.564（P<001）与0.688（P<0.01），比二组法分别降低了177%、8.0%和10.9%，固定恢复系时两种方法预测效果基本一致；4）对于水稻碾磨品质的分子预测，固定不育系的预测效果最佳，二组法的预测效果显著优于三组法。在3个碾磨品质指标中，整精米率预测效果最好，其次为精米率，糙米率较差。

Molecular Prediction of Milling Quality of indica Hybrid Rice Based on Different Analyzing Strategies

Brown rice rate(BRR),milled rice rate(MRR) and head rice rate(HRR) are important traits determining rice milling quality,so the effective prediction of these traits is of great importance to hybrid rice breeding.Positive loci(PL) and effect-increasing loci(IL) for BRR,MRR and HRR detected with 174 SSR markers were used to predict the performance of these three milling quality traits of 81 hybrid combinations derived from diallel crossing between 9 male sterile lines and 9 restorer lines via two-group and three-group methods,respectively.The results indicated that: 1) the correlation coefficients predicted via the two-group method with IL of BRR,MRR and HRR were 0.553(P<0.01),0.613(P<0.01) and 0.772(P<0.01),respectively,significantly higher than those with PL;2) with fixed male sterile lines,the correlation coefficients and significant level of three milling quality traits predicted with IL were much higher than those with fixed restorer lines,suggesting that male sterile lines exerted a higher influence on BRR,MRR and HRR than restorer lines;3) with fixed male sterile lines,the predicting correlation coefficients of BRR,MRR,and HRR via three-group method were 0.466(P<0.05),0.564(P<0.01) and 0.688(P<0.01) correspondingly,decreased by 17.7%,8.0% and 10.9% than those via two-group method,while the coefficients agreed well with each other with fixed restorer lines;4) to the molecular prediction of milling quality in hybrid rice,the efficiency with fixed male sterile lines is statistically higher than that with fixed restorer lines,results by two-group method is better than that by three-group method.And among these three milling quality traits,HRR is more easier to predict,followed by MRR and BRR.