杂交水稻育种骨干亲本的米质分析

全面系统地评价杂交水稻骨干育种亲本的米质性状,对于杂交水稻稻米品质性状改良具有重要的指导意义。本研究对274份来源于中国十余个水稻主产区的骨干育种亲本及部分国外来源的育种材料进行了基于类群划分的米质分析。研究结果表明,7项米质性状中,籼稻糙米率、透明度、胶稠度和直链淀粉含量的平均值达到三等以上标准,粳稻糙米率、整精米率、透明度、胶稠度和直链淀粉含量的平均值达到三等以上标准。籼稻米质性状优质达标率变化范围为27.7%~97.7%,粳稻米质性状优质达标率变化范围为16.7%~100%,籼、粳稻垩白性状的优质达标率均较低。籼稻类群中,恢复系和保持系的垩白性状和直链淀粉含量是米质性状改良的重点,常规稻直链淀粉含量较优,热带籼稻中IR43、GIZA 178等米质性状优良,是杂交育种的有利种质资源。筛选出10项米质指标均达三级以上的各类亲本材料共23份,这些育种材料可以作为优异的米质性状改良的基因供体加以利用。另一方面,应加强垩白性状优良的种质资源的引进和利用。

Grain Quality of Primal Parental Lines in Hybrid Rice Breeding

Grain quality of primal parental rice lines is a key element for evaluation in breeding new varieties.This article presents the results of a population structure-based analysis on the quality of 274 primal parental lines of hybrid rice used in China and abroad.It was found that,in general,the average brown rice yield and the transparency,gel consistency and amylose content (AC) of the grains of indica rice exceeded the grading criteria for the 3rdquality tier.For japonica rice,the brown rice yield,head milled rice rate,and the transparency,gel consistency and AC of the grains met the high quality criteria.The percentages of indica that showed superior quality indices varied between 27.7% to 97.7% among all;while japonica,16.7% to 100%.Grain chalkiness were low for all indica and japonica.Among indica,chalkiness and AC needed the greatest attention for improvements onthe restorer as well as the maintainer lines;AC was good on the conventional rice;and,the overall quality of IR43 and GIZA 178 tropical indica was considered excellent for breeding purposes.In all,23 primal parental lines were found to have all 10 quality traits graded as high,or higher than,the 3rd tier.Hence,they could be potential candidates for breeding new rice varieties.As for the deficiency on grain chalkiness,it was recommended that specific germplasms with the desirable trait be introduced for breeding to mitigate the shortcoming in the future.