Tsehaye Yirgalem, Menamo Temesgen M, Demelash Habtamu, Abay Fetien, Tadesse Taye, Bantte Kassahun
Department of Dryland Crop and Horticultural Sciences, College of Dryland Agriculture and Natural Resources, Mekelle University, Mekelle, Ethiopia.
Tigray Agricultural Research Institute, Mekelle, Ethiopia.
Sci Rep. 2025 Aug 28;15(1):31727. doi: 10.1038/s41598-025-99012-w.
Sorghum (Sorghum bicolour (L.) Moench) grown under rain-fed conditions is usually affected by drought stress at different stages, resulting in reduced yield. Determining the genetic control of root system architecture (RSA) in plants via multi-locus genome-wide association study (GWAS) is very important to improve moisture stress resistance in sorghum. The objective of this study was, therefore, to identify genomic regions underlying RSA traits in sorghum at the early growth stage among 200 genotypes. A total of 124 QTNs were identified on all chromosomes that are significantly linked with the nine root and shoot traits using one or more of the six ML-GWAS models, with a LOD score threshold of ≥ 3. Among these identified QTNs, a total of 38 significant QTNs were identified in at least two ML-GWAS models. Out of the 38 detected QTNs, 28 were co-located with previously reported QTLs for the RSA, while the remaining 10 QTNs were distinct. We identified 438 co-localized genes within a 65 kb window upstream and downstream of 38 QTNs for studied traits. Among these genes, 153 were uncharacterized or unknown while the rest of the genes have protein description. Moreover, 16 genes contained the QTNs intergenic region of within the gene's sequences. These genes may regulate root development in the seedling stage. Further analysis on these genes might be important to explore the genetic structure of RSA of sorghum.
在雨养条件下种植的高粱（Sorghum bicolour (L.) Moench）通常在不同阶段受到干旱胁迫，导致产量降低。通过多位点全基因组关联研究（GWAS）确定植物根系结构（RSA）的遗传控制对于提高高粱的耐水分胁迫能力非常重要。因此，本研究的目的是在200个基因型中鉴定高粱早期生长阶段RSA性状的基因组区域。使用六个ML-GWAS模型中的一个或多个，在所有染色体上共鉴定出124个与九个根和地上部性状显著相关的QTN，LOD得分阈值≥3。在这些鉴定出的QTN中，共有38个显著QTN在至少两个ML-GWAS模型中被鉴定出来。在检测到的38个QTN中，28个与先前报道的RSA QTL共定位，其余10个QTN是不同的。我们在38个研究性状的QTN上下游65 kb窗口内鉴定出438个共定位基因。在这些基因中，153个未被表征或未知，其余基因有蛋白质描述。此外，16个基因在其基因序列内包含QTN基因间区域。这些基因可能在幼苗期调节根系发育。对这些基因的进一步分析可能对探索高粱RSA的遗传结构很重要。
