Wu Xun, Li Yongxiang, Shi Yunsu, Song Yanchun, Zhang Dengfeng, Li Chunhui, Buckler Edward S, Li Yu, Zhang Zhiwu, Wang Tianyu
Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Nanchong Academy of Agricultural Sciences, Nanchong, Sichuan, China.
Plant Biotechnol J. 2016 Jul;14(7):1551-62. doi: 10.1111/pbi.12519. Epub 2016 Jan 23.
Both insufficient and excessive male inflorescence size leads to a reduction in maize yield. Knowledge of the genetic architecture of male inflorescence is essential to achieve the optimum inflorescence size for maize breeding. In this study, we used approximately eight thousand inbreds, including both linkage populations and association populations, to dissect the genetic architecture of male inflorescence. The linkage populations include 25 families developed in the U.S. and 11 families developed in China. Each family contains approximately 200 recombinant inbred lines (RILs). The association populations include approximately 1000 diverse lines from the U.S. and China. All inbreds were genotyped by either sequencing or microarray. Inflorescence size was measured as the tassel primary branch number (TBN) and tassel length (TL). A total of 125 quantitative trait loci (QTLs) were identified (63 for TBN, 62 for TL) through linkage analyses. In addition, 965 quantitative trait nucleotides (QTNs) were identified through genomewide study (GWAS) at a bootstrap posterior probability (BPP) above a 5% threshold. These QTLs/QTNs include 24 known genes that were cloned using mutants, for example Ramosa3 (ra3), Thick tassel dwarf1 (td1), tasselseed2 (ts2), liguleless2 (lg2), ramosa1 (ra1), barren stalk1 (ba1), branch silkless1 (bd1) and tasselseed6 (ts6). The newly identified genes encode a zinc transporter (e.g. GRMZM5G838098 and GRMZM2G047762), the adapt in terminal region protein (e.g. GRMZM5G885628), O-methyl-transferase (e.g. GRMZM2G147491), helix-loop-helix (HLH) DNA-binding proteins (e.g. GRMZM2G414252 and GRMZM2G042895) and an SBP-box protein (e.g. GRMZM2G058588). These results provide extensive genetic information to dissect the genetic architecture of inflorescence size for the improvement of maize yield.
雄花序大小不足和过大都会导致玉米产量下降。了解雄花序的遗传结构对于实现玉米育种的最佳花序大小至关重要。在本研究中，我们使用了约八千个自交系，包括连锁群体和关联群体，来剖析雄花序的遗传结构。连锁群体包括在美国培育的25个家系和在中国培育的11个家系。每个家系包含约200个重组自交系（RIL）。关联群体包括来自美国和中国的约1000个不同品系。所有自交系均通过测序或微阵列进行基因分型。花序大小通过雄穗一级分枝数（TBN）和雄穗长度（TL）来衡量。通过连锁分析共鉴定出125个数量性状位点（QTL）（TBN为63个，TL为62个）。此外，通过全基因组研究（GWAS）在自展后验概率（BPP）高于5%阈值时鉴定出965个数量性状核苷酸（QTN）。这些QTL/QTN包括24个使用突变体克隆的已知基因，例如Ramosa3（ra3）、粗雄穗矮化1（td1）、雄花不孕2（ts2）、无叶舌2（lg2）、Ramosa1（ra1）、空秆1（ba1）、分枝无丝1（bd1）和雄花不孕6（ts6）。新鉴定的基因编码一种锌转运蛋白（如GRMZM5G838098和GRMZM2G047762）、末端区域衔接蛋白（如GRMZM5G885628）、O-甲基转移酶（如GRMZM2G147491）、螺旋-环-螺旋（HLH）DNA结合蛋白（如GRMZM2G414252和GRMZM2G042895）和一个SBP-box蛋白（如GRMZM2G058588）。这些结果为剖析花序大小的遗传结构以提高玉米产量提供了丰富的遗传信息。
