College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China.
Cereal Crops Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou, China.
Nat Plants. 2022 Dec;8(12):1408-1422. doi: 10.1038/s41477-022-01274-z. Epub 2022 Nov 17.
Appropriate root system architecture (RSA) can improve maize yields in densely planted fields, but little is known about its genetic basis in maize. Here we performed root phenotyping of 14,301 field-grown plants from an association mapping panel to study the genetic architecture of maize RSA. A genome-wide association study identified 81 high-confidence RSA-associated candidate genes and revealed that 28 (24.3%) of known root-related genes were selected during maize domestication and improvement. We found that modern maize breeding has selected for a steeply angled root system. Favourable alleles related to steep root system angle have continuously accumulated over the course of modern breeding, and our data pinpoint the root-related genes that have been selected in different breeding eras. We confirm that two auxin-related genes, ZmRSA3.1 and ZmRSA3.2, contribute to the regulation of root angle and depth in maize. Our genome-wide identification of RSA-associated genes provides new strategies and genetic resources for breeding maize suitable for high-density planting.
适当的根系结构（RSA）可以提高密植条件下玉米的产量，但目前对于玉米中 RSA 的遗传基础知之甚少。在这里，我们对来自关联图谱面板的 14301 株田间生长的植物进行了根系表型分析，以研究玉米 RSA 的遗传结构。全基因组关联研究鉴定出 81 个与 RSA 高度相关的候选基因，并揭示了 28 个（24.3%）已知的与根系相关的基因在玉米驯化和改良过程中被选择。我们发现现代玉米育种选择了具有陡峭角度的根系。与陡峭根系角度相关的有利等位基因在现代育种过程中不断积累，我们的数据确定了不同育种时代选择的与根系相关的基因。我们证实，两个与生长素相关的基因 ZmRSA3.1 和 ZmRSA3.2 有助于调节玉米的根角度和深度。我们对与 RSA 相关的基因的全基因组鉴定为培育适合高密度种植的玉米提供了新的策略和遗传资源。
