Tobacco Research Insistitute of Chinese Academy of Agriculture Sciences, Qingdao, China.
Rice Institute, Sichuan Agriculture University, Chengdu, China.
PeerJ. 2023 Mar 7;11:e14866. doi: 10.7717/peerj.14866. eCollection 2023.
Straighthead is a physiological disorder of rice ( L.) that causes dramatic yield loss in susceptible cultivars. This disorder is found worldwide and is reported to increasingly occur in the southern United States. Genetic resistance breeding has been considered as one of the most efficient methods for straighthead prevention because the traditional prevention method wastes water and costs labor. In this study, we analyzed the genetic effects of five straighthead quantitative trait loci (QTLs), namely, AP3858-1 (), RM225 (), RM2 (), RM206 (), and RM282 (), on the recombinant inbred lines (RILs) developed from Jing185/Cocodrie and Zhe733/R312 populations using our five previously identified markers linked to these QTLs. As a result, recombinant inbred lines (RILs) with four resistant alleles at the four loci (AP3858-1, RM225, RM2, and RM206) exhibited the highest straighthead resistance. This result suggests that the four markers could be efficiently used to select the straighthead-resistant recombinant inbred lines (RILs). Furthermore, by using AP3858-1, we successfully obtained five straighthead-resistant recombinant inbred lines (RILs) with more than 50% genetic similarity to Cocodrie. These markers and recombinant inbred lines (RILs) can be used for future straighthead resistance breeding through marker-assisted selection.
直头病是一种影响水稻（Oryza sativa）的生理病害，会导致感病品种产量大幅下降。该病害在全球范围内均有发现，并据报道在美国南部的发病率呈上升趋势。遗传抗性育种被认为是预防直头病最有效的方法之一，因为传统的预防方法既浪费水又耗费劳力。在本研究中，我们利用先前鉴定的与五个直头病数量性状位点（QTLs）（AP3858-1、RM225、RM2、RM206 和 RM282）相关的五个标记，对来自 Jing185/Cocodrie 和 Zhe733/R312 群体的重组自交系（RILs）进行了遗传效应分析。结果表明，在四个位点（AP3858-1、RM225、RM2 和 RM206）上具有四个抗性等位基因的重组自交系（RILs）表现出最高的直头病抗性。这一结果表明，这四个标记可以有效地用于选择直头病抗性的重组自交系（RILs）。此外，利用 AP3858-1，我们成功获得了五个与 Cocodrie 遗传相似度超过 50%的直头病抗性重组自交系（RILs）。这些标记和重组自交系（RILs）可用于未来通过标记辅助选择进行直头病抗性育种。
