Yang Yongqing, Zhao Qingsong, Li Xinxin, Ai Wenqin, Liu Dong, Qi Wandong, Zhang Mengchen, Yang Chunyan, Liao Hong
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry UniversityFuzhou, China.
Root Biology Center, Fujian Agriculture and Forestry UniversityFuzhou, China.
Front Plant Sci. 2017 Aug 23;8:1466. doi: 10.3389/fpls.2017.01466. eCollection 2017.
Soybean [ (L.) Merr] is an important legume crop and its yield largely depends on root architecture (RA) and biological nitrogen fixation (BNF). However, the relationship between RA and BNF, and its genetics behind remain unclear. Here, two soybean genotypes contrasting in RA and their 175 recombinant inbred lines (RILs) were evaluated in field. The shallow-root parent, JD12, had better nodulation and higher yield than the deep-root parent, NF58. Strong correlations between shoot dry weight (SDW) and RA or BNF traits existed in the RILs, and the shallow-root group had more and heavier nodules, as well as higher SDW. After inoculating with rhizobia, roots became shallower and bigger, showing strong synergistic interactions between RA and BNF. In total, 70 QTLs were identified for the 21 tested traits. Among them, , , and , were newly identified QTLs for BNF and/or RA traits in soybean, which co-located with the QTLs for SDW detected presently, and with the QTLs for yield identified previously. The results together suggest that there are synergistic interactions between RA and BNF, and the QTLs identified here could be used for breeding new soybean varieties with higher yields through optimization of RA traits and BNF capacity.
大豆[（L.）Merr]是一种重要的豆科作物，其产量很大程度上取决于根系结构（RA）和生物固氮（BNF）。然而，RA与BNF之间的关系及其背后的遗传学仍不清楚。在此，对两种根系结构不同的大豆基因型及其175个重组自交系（RILs）进行了田间评估。浅根亲本JD12比深根亲本NF58具有更好的结瘤和更高的产量。在RILs中，地上部干重（SDW）与RA或BNF性状之间存在强相关性，浅根组有更多、更重的根瘤以及更高的SDW。接种根瘤菌后，根系变浅且变大，表明RA与BNF之间存在强烈的协同相互作用。总共为21个测试性状鉴定出70个QTL。其中， 、 和 是大豆中BNF和/或RA性状新鉴定出的QTL，它们与目前检测到的SDW的QTL以及先前鉴定出的产量的QTL共定位。这些结果共同表明RA与BNF之间存在协同相互作用，这里鉴定出的QTL可用于通过优化RA性状和BNF能力来培育高产大豆新品种。
