优良水稻染色体片段代换系Z746的鉴定及重要农艺性状QTL定位及其验证  

Identification of an excellent rice chromosome segment substitution line Z746 and QTL mapping and verification of important agronomic traits

作　　者：沈文强 赵冰冰 于国玲 李凤菲 朱小燕[1] 马福盈 李云峰[1] 何光华[1] 赵芳明[1] SHEN Wen-Qiang;ZHAO Bing-Bing;YU Guo-Ling;LI Feng-Fei;ZHU Xiao-Yan;MA Fu-Ying;LI Yun-Feng;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》2021年第3期451-461,共11页Acta Agronomica Sinica

基　　金：国家重点研发计划项目(2017YFD0100202);重庆市科委项目(cstc2016shms-ztzx0017,CSTCCXLJRC201713);西南大学基本业务费专项创新团队项目(XDJK2017A004)资助。

摘　　要：粒型、株高及穗部组成性状与产量形成密切相关,是水稻重要农艺性状,但遗传基础复杂。染色体片段代换系是用于复杂性状遗传研究的良好材料。本研究鉴定了一个以日本晴为受体、西恢18为供体亲本的水稻优良染色体片段代换系Z746。Z746携带来自西恢18的7个代换片段,平均代换长度为3.99 Mb,其株高、粒长和穗部性状均与受体存在显著差异。进一步通过日本晴与Z746杂交构建的次级F2群体共检测到36个相关QTL,分布于2号、3号、4号、6号和11号染色体。其中5个可能与已克隆基因等位,如qPH3-1等,8个可被多次检出,表明这些是遗传稳定的主效QTL。Z746的粒长主要由4个QTL(qGL3、qGL4、qGL2、qGL6)控制,其中qGL3和qGL4对粒长变异的贡献率分别为60.28%和27.47%。株高由5个QTL控制,穗长由4个QTL控制,每穗粒数由2个QTL控制,千粒重由2个QTL控制。然后以MAS在F3共选出8个单片段代换系,并以此在F4进行了相关QTL验证,共有24个QTL可被8个单片段代换系(SSSL)检出,重复检出率为66.7%,表明这些QTL遗传稳定。本研究为目的QTL的进一步遗传机制研究及分子设计育种奠定了良好基础。The important agronomic traits,such as grain type,plant height,and panicle composition,are closely related to rice yield,and their gene inheritance is complex.Chromosome segment substitution lines(CSSLs)are useful materials for studying these complex traits.An excellent CSSL,Z746,containing seven substitution segments and with an average substitution length of 3.99 Mb,was identified from Nipponbare as a recipient and‘Xihui 18’as a donor parent.There were significant differences in plant height,panicle composition and grain size between Z746 and Nipponbare.Furthermore,a total of 36 quantitative trait loci(QTL)were detected on chromosomes 2,3,4,6,and 11 in the secondary F2 population constructed by hybridization between Nipponbare and Z746.Five of them may be alleles of the cloned genes,such as qPH3-1,and eight can be detected by multiple times,indicating that these were genetically stable major QTLs.The grain length in Z746 was mainly controlled by four QTLs(qGL3,qGL4,qGL2,and qGL6),and the phenotypic variation of qGL3 and qGL4 for grain length was 60.28%and 27.47%,respectively.Plant height was controlled by five QTLs,panicle length by four QTLs,grain number per panicle by two QTLs,and the 1000-grain weight by two QTLs.Eight single segment substitution lines(SSSLs)were developed in F3 population by molecular marker-assisted selection(MAS),and relevant QTLs verification was conducted in F4.Finally,24 QTLs were detected by 8 SSSLs and the repeat detection rate was 66.7%,indicating that these QTLs were genetically stable.These results provide a good foundation for further research on genetic mechanisms of the target QTLs and molecular design breeding.

关 键 词：水稻 染色体片段代换系 粒长 株高 穗部组成 QTL定位 

分 类 号：S511[农业科学—作物学]