Original Research ARTICLE
QTL-by-Environment interaction in the response of maize root and shoot traits to different water regimes
- 1Yangzhou University, China
- 2Jiangsu Yanjiang Institute of Agricultural Sciences, China
Drought is a major abiotic stress factor limiting maize production, and elucidating the genetic control of root system architecture and plasticity to water-deficit stress is a crucial problem to improve drought adaptability. In this study, 13 root and shoot traits and genetic plasticity were evaluated in a recombinant inbred line (RIL) population under well-watered (WW) and water stress (WS) conditions. Significant phenotypic variation was observed for all observed traits both under WW and WS conditions. Most of the measured traits showed significant genotype–environment interaction (GEI) in both environments. Strong correlations were observed among traits in the same class. Multi-environment (ME) and multi-trait (MT) QTL analyses were conducted for all observed traits. A total of 48 QTLs were identified by ME, including 15 QTLs associated with 9 traits showing significant QTL-by-Environment interactions (QEI). QTLs associated with crown root angle (CRA2) and crown root length (CRL1) were identified as having antagonistic pleiotropic effects, while 13 other QTLs showed signs of conditional neutrality, including 9 and 4 QTLs detected under WW and WS conditions, respectively. MT analysis identified 14 pleiotropic QTLs for 13 traits, SNP20 (firstname.lastname@example.org cM) was associated with the length of crown root, primary root and seminal root and might contribute to increases in root length under WS condition. Taken together, these findings contribute to our understanding of the phenotypic and genotypic patterns of root plasticity in response to water deficiency, which will be useful to improve drought tolerance in maize.
Keywords: Maize, Root system architecture, QTL-by-environment interaction, root plasticity, drought, QTL mapping
Received: 04 Oct 2017;
Accepted: 08 Feb 2018.
Edited by:Roberto Papa, Università Politecnica delle Marche, Italy
Reviewed by:Tania Gioia, Univeristà degli Studi della Basilicata, Italy
Silvio Salvi, Università di Bologna, Italy
Copyright: © 2018 Li, Zhang, Yin, Zhu, Pan, Xu, Wang, Hao, Fang, Xu and Yang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Prof. Chenwu Xu, Yangzhou University, Yangzhou, China, email@example.com
Prof. Zefeng Yang, Yangzhou University, Yangzhou, China, firstname.lastname@example.org