Gupta Rigyan, Prodhan Shamsul H, Hasan Md Nazmul, Begum Shamsun Nahar, Rani Mohammad Hasanuzzaman, Islam Mirza Mofazzal, Ashrafuzzaman Md
Department of Genetic Engineering & Biotechnology (GEB), School of Life Sciences, Shahjalal University of Science and Technology (SUST), Sylhet, Bangladesh.
Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh, Bangladesh.
PLoS One. 2025 Jul 2;20(7):e0327162. doi: 10.1371/journal.pone.0327162. eCollection 2025.
Rising tropospheric ozone concentrations pose a significant threat to crop production in many Asian countries like Bangladesh, necessitating the development of ozone-tolerant rice (Oryza sativa L.) varieties. This study investigates the response of the OsORAP1 allele-an important regulator of the plant's response to ozone stress, whose expression is associated with ozone-induced damage-in different rice varieties, particularly Kasalath-type and Nipponbare-type, under treatment with ethylenediurea (EDU), a protective antiozonant used in plant research under ambient ozone stress. The experiment, conducted during the 2022 irrigated season, involved growing of 20 rice varieties under a split-plot design with and without 300 ppm EDU treatment, followed by genomic DNA collection at the vegetative stage to differentiate Kasalath-types and Nipponbare-types, and RNA extraction from 10 selected varieties at the flowering stage for gene expression analysis. The research revealed distinct genetic responses between the two types, with Nipponbare-type varieties showing significant increases in OsORAP1 expression and more leaf bronzing score (LBS) without EDU protection. In contrast, Kasalath-type varieties exhibited less pronounced responses due to their inherent tolerance to ozone stress. The effects of EDU on with Kasalath-type varieties responding notably in parameters such as ineffective tillers and straw yield, while Nipponbare-types showed significant changes in unfilled grains and grain yield. Additionally, differences were observed in how EDU treatment influenced reflectance indices parameters, indicating variability in how these varieties mitigate ozone stress. The study underscores the complex interaction between genetic factors, environmental conditions, and treatment in shaping the response of rice varieties to EDU, and suggests future research to further explore the genetic mechanisms, particularly the role of OsORAP1, that contribute to these differential responses.
对流层臭氧浓度上升对许多亚洲国家（如孟加拉国）的作物生产构成了重大威胁，因此有必要培育耐臭氧水稻（Oryza sativa L.）品种。本研究调查了OsORAP1等位基因（植物对臭氧胁迫反应的重要调节因子，其表达与臭氧诱导的损伤相关）在不同水稻品种，特别是卡萨拉思型和日本晴型品种中，在乙二脲（EDU，一种在环境臭氧胁迫下用于植物研究的保护性抗臭氧剂）处理下的反应。该实验在2022年灌溉季节进行，采用裂区设计种植20个水稻品种，分别进行300 ppm EDU处理和不处理，随后在营养阶段收集基因组DNA以区分卡萨拉思型和日本晴型，并在开花阶段从10个选定品种中提取RNA进行基因表达分析。研究揭示了这两种类型之间不同的遗传反应，在没有EDU保护的情况下，日本晴型品种的OsORAP1表达显著增加，叶片青铜化评分（LBS）更高。相比之下，卡萨拉思型品种由于其对臭氧胁迫的固有耐受性，表现出不太明显的反应。EDU对卡萨拉思型品种的无效分蘖和秸秆产量等参数有显著影响，而日本晴型品种在空粒和籽粒产量方面有显著变化。此外，观察到EDU处理对反射率指数参数的影响存在差异，表明这些品种减轻臭氧胁迫的方式存在差异。该研究强调了遗传因素、环境条件和处理之间在塑造水稻品种对EDU反应方面的复杂相互作用，并建议未来开展研究进一步探索导致这些差异反应的遗传机制，特别是OsORAP1的作用。
