Analyses and identifications of quantitative trait loci and candidate genes controlling mesocotyl elongation in rice  

作　　者：ZHANG Xi-juan LAI Yong-cai MENG Ying TANG Ao DONG Wen-jun LIU You-hong LIU Kai WANG Li-zhi YANG Xian-li WANG Wen-long DING Guo-hua JIANG Hui REN Yang JIANG Shu-kun 

机构地区：[1]Institute of Crop Cultivation and Tillage,Heilongjiang Academy of Agricultural Sciences,Heilongjiang Provincial Key Laboratory of Crop Physiology and Ecology in Cold Region,Heilongjiang Provincial Engineering Technology Research Center of Crop Cold Damage,Harbin 150086,P.R.China [2]Northeast Branch of National Salt–Alkali Tolerant Rice Technology Innovation Center,Harbin 150086,P.R.China [3]Qiqihar Branch,Heilongjiang Academy of Agricultural Sciences,Qiqihar 161006,P.R.China

出　　处：《Journal of Integrative Agriculture》2023年第2期325-340,共16页农业科学学报（英文版）

基　　金：supported by grants from the Natural Science Foundation of Heilongjiang Province, China (LH2020C098);the Fundamental Research Funds for the Research Institutes of Heilongjiang Province, China (CZKYF2020A001);the National Key Research and Development Program of China (2016YFD0300104);the Heilongjiang Province Agricultural Science and Technology Innovation Project, China (2020JCQN001, 2019JJPY007, 2020FJZX049, 2021QKPY009, 2021CQJC003)。

摘　　要：Rice direct seeding has the significant potential to save labor and water,conserve environmental resources,and reduce greenhouse gas emissions tremendously.Therefore,rice direct seeding is becoming the major cultivation technology applied to rice production in many countries.Identifying and utilizing genes controlling mesocotyl elongation is an effective approach to accelerate breeding procedures and meet the requirements for direct-seeded rice(DSR) production.This study used a permanent mapping population with 144 recombinant inbred lines(RILs) and 2 828 bin-markers to detect quantitative trait loci(QTLs) associated with mesocotyl length in 2019 and 2020.The mesocotyl lengths of the rice RILs and their parents,Lijiangxintuanheigu(LTH) and Shennong 265(SN265),were measured in a growth chamber at 30°C in a dark environment.A total of 16 QTLs for mesocotyl length were identified on chromosomes 1(2),2(4),3(2),4,5,6,7,9,11(2),and 12.Seven of these QTLs,including qML1a,qML1b,qML2d,qML3a,qML3b,qML5,and qML11b,were reproducibly detected in both years via the interval mapping method.The major QTL,qML3a,was reidentified in two years via the composite interval mapping method.A total of 10 to 413 annotated genes for each QTL were identified in their smallest genetic intervals of 37.69 kb to 2.78 Mb,respectively.Thirteen predicted genes within a relatively small genetic interval(88.18 kb) of the major mesocotyl elongation QTL,qML3a,were more thoroughly analyzed.Finally,the coding DNA sequence variations among SN265,LTH,and Nipponbare indicated that the LOC_Os03g50550 gene was the strongest candidate gene for the qML3a QTL controlling the mesocotyl elongation.This LOC_Os03g50550 gene encodes a mitogen-activated protein kinase.Relative gene expression analysis using qRT-RCR further revealed that the expression levels of the LOC_Os03g50550 gene in the mesocotyl of LTH were significantly lower than in the mesocotyl of SN265.In conclusion,these results further strengthen our knowledge about rice’s genetic mechanisms of mesocot

关 键 词：japonica rice direct-seeded rice(DSR) mesocotyl elongation quantitative trait loci candidate gene 

分 类 号：S511[农业科学—作物学]