Fu Yafang, Liu Jianchao, Xia Zhenqing, Wang Qi, Zhang Shibo, Zhang Guixin, Lu Haidong
College of Agronomy, Northwest A&F University, Yangling, Xianyang 712100, China.
Plants (Basel). 2022 May 26;11(11):1417. doi: 10.3390/plants11111417.
Nitrogen (N) is one of the important factors affecting maize root morphological construction and growth development. An association panel of 124 maize inbred lines was evaluated for root and shoot growth at seedling stage under normal N (CK) and low N (LN) treatments, using the paper culture method. Twenty traits were measured, including three shoot traits and seventeen root traits, a genome-wide association study (GWAS) was performed using the Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) methods. The results showed that LN condition promoted the growth of the maize roots, and normal N promoted the growth of the shoots. A total of 185 significant SNPs were identified, including 27 SNPs for shoot traits and 158 SNPs for root traits. Four important candidate genes were identified. Under LN conditions, the candidate gene was significantly correlated with the number of crown roots, was correlated with plant height. Under CK conditions, the candidate gene was correlated with the length and area of seminal roots, was correlated with the total root length. The four candidate genes all responded to the LN treatment. The research results provide genetic resources for the genetic improvement of maize root traits.
氮（N）是影响玉米根系形态构建和生长发育的重要因素之一。采用纸培法，在正常氮（CK）和低氮（LN）处理下，对124个玉米自交系的关联群体在苗期的根和地上部生长进行了评价。测定了20个性状，包括3个地上部性状和17个根系性状，采用贝叶斯信息和连锁不平衡迭代嵌套关键路径（BLINK）方法进行全基因组关联研究（GWAS）。结果表明，低氮条件促进了玉米根系的生长，正常氮促进了地上部的生长。共鉴定出185个显著的单核苷酸多态性（SNP），其中包括27个与地上部性状相关的SNP和158个与根系性状相关的SNP。鉴定出4个重要的候选基因。在低氮条件下，候选基因与冠根数量显著相关，与株高相关。在正常氮条件下，候选基因与胚根长度和面积相关，与总根长相关。这4个候选基因均对低氮处理有响应。研究结果为玉米根系性状的遗传改良提供了遗传资源。
