基于水稻长大粒染色体片段代换系Z66的粒型QTL的鉴定及其聚合分析  

Identification and pyramid analysis of QTLs for grain size based on rice long-large-grain chromosome segment substitution line Z66

作　　者：向思茜 李儒香 徐光益 邓岢莉 余金琎 李苗苗 杨正林[1] 凌英华[1] 桑贤春[1] 何光华[1] 赵芳明[1] XIANG Si-Qian;LI Ru-Xiang;XU Guang-Yi;DENG Ke-Li;YU Jin-Jin;LI Miao-Miao;YANG Zheng-Lin;LING Ying-Hua;SANG Xian-Chun;HE Guang-Hua;ZHAO Fang-Ming(Rice Research Institute,Southwest University/Academy of Agricultural Sciences,Southwest University/Transgenic Plants and Safety Control,Chongqing Key Laboratory,Chongqing 400715,China)

机构地区：[1]西南大学水稻研究所/西南大学农业科学研究院/转基因植物与安全控制重庆市重点实验室,重庆400715

出　　处：《作物学报》2023年第3期731-743,共13页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(32072039);西南大学种质创制专项项目资助。

摘　　要：水稻籽粒大小是一个复杂的农艺性状,受多基因控制。染色体片段代换系是创造自然变异的有效手段,也是复杂性状研究的理想材料。本研究构建了一个新的水稻长大粒染色体片段代换系Z66,Z66以日本晴的基因组为遗传背景,含有来自R225的12个代换片段,平均代换长度为3.32Mb。然后,以日本晴/Z66创建的次级F2群体定位出12个控制水稻籽粒大小的QTL,并培育出具有目标QTL的5个新单片段代换系(S1~S5)和4个新双片段代换系(D1~D4)。其中有9个QTL(qGL3、qGL7、qGL10、qGW6、qGW10、qRLW3、qRLW10、qGWT3、qGWT10)可被单片段代换系所验证,表明这些QTL遗传稳定。此外,还利用单片段代换系鉴定到6个新的QTL(qGL9-2、qGW9-2、qRLW6、qRLW7、qRLW9-2、qGWT7)。在这18个QTL中,qGL9-2、qRLW9-1、qRLW9-2、qGW9-2、qGWT9-2可能是新鉴定的QTL。双基因聚合分析表明,不同QTL间聚合产生不同的上位性效应。如qRLW3(a=0.21)和qRLW9-2(a=0.08)聚合产生了0.10的上位性效应,使D2具有比受体日本晴、S1(qRLW3)和S4(qRLW9-2)更大的谷粒长宽比,且差异显著。qGWT3(a=3.99)和qGWT10(a=3.98)聚合产生了-5.35的上位性效应,其遗传效应(2.62)使D3的千粒重比日本晴显著增加,而比S1(qGWT3)和S5(qGWT10)显著减少。了解QTL间的互作效应可对未来基因型的表型进行预测,从而对实现智能型设计育种至关重要。Rice grain size is a complex agronomic trait,controlled by multiple genes.Chromosome segment substitution lines are an effective method for creating natural occurring variations and are as the ideal materials for exploring the complex traits.In this study,a novel rice long-large grain chromosome segment substitution line Z66 was developed.Z66 contained 12 substitution segments from R225(average substitution length was 3.32 Mb)based on the genetic backgrounds of Nipponbare.Then,12 QTLs for rice grain size were identified by the secondary F2population from Nipponbare/Z66,and 5 novel single-segment substitution lines(SSSLs,S1-S5),and 4 novel double-segment substitution lines(DSSLs,D1-D4)harboring target QTL were developed.Among them,9 QTLs(qGL3,qGL7,qGL10,qGW6,qGW10,qRLW3,qRLW10,qGWT3,and qGWT10)could be verified by the SSSLs,indicating that these QTLs were genetically stable.In addition,6 novel QTLs(qGL9-2,qGW9-2,qRLW6,qRLW7,qRLW9-2,and qGWT7)were detected by the SSSLs.Among 18 QTLs,5 QTLs(qGL9-2,qRLW9-1,qRLW9-2,qGW9-2,and qGWT9-2)might be novel.Target QTLs pyramiding showed that the pyramid of different QTLs had various epistasis effects.For example,the pyramids of qRLW3(a=0.21)and qRLW9-2(a=0.08)produced an epistasis effect of 0.10,which made the ratio of grain length to width in D2 significantly larger than that in Nipponbare,S1(qRLW3),and S4(qRLW9-2).The pyramid of qGWT3(a=3.99)and qGWT10(a=3.98)yielded an epistasis effect of-5.35,and its genetic effects in D3(2.62 g)significantly increased 1000-grain weight of D3 than in Nipponbare,but significantly decreased than that in S1(qGWT3)and S5(qGWT10).Understanding the interaction effects between target QTLs can predict the phenotype of futural QTL pyramid genotypes,which is important for intelligent design breeding in rice.

关 键 词：水稻 粒型 QTL 染色体代换片段 加性效应 上位性效应 

分 类 号：S511[农业科学—作物学]