Sahasakul Yuraporn, Aursalung Amornrat, Thangsiri Sirinapa, Temviriyanukul Piya, Inthachat Woorawee, Pongwichian Pirach, Sasithorn Kamontip, Suttisansanee Uthaiwan
Food and Nutrition Academic and Research Cluster, Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom, 73170, Thailand.
Land Development Department, Phaholyothin Rd., Lat Yao, Chatuchak, Bangkok, 10900, Thailand.
Sci Rep. 2025 Apr 12;15(1):12567. doi: 10.1038/s41598-025-97864-w.
Rice (Oryza sativa) is a staple food crop with a significant role in nutrition and health. Its production yield mainly depends on climatic conditions. Soil salinity, an abiotic factor as a resulting from drought, also impacts rice growth, production, and quality. Researchers have widely investigated newly developed salt-tolerant rice varieties and suitable fertilizers to enhance rice yield and quality. However, the effects of planting times of in- season and off-season rice varieties grown in soils with varying salinity levels on rice qualities, such as nutrients, bioactive compounds, and health-related properties remain unexamined. This study evaluated the qualities (nutrients, phenolics, and antioxidant activities) of thirty-eight in season- and off-season rice samples grown in soils with different physicochemical properties: electrical conductivity extract (EC), pH (pH), organic matter (OM), available minerals (potassium and phosphorus), and soluble salts (calcium, magnesium, sodium, and potassium). Results indicated that rice nutrients, total phenolic contents (TPCs), and antioxidant activities were influenced by planting seasons rather than rice varieties or the soil salinity marker EC. The in-season rice samples exhibited higher levels of protein, iron (Fe), TPCs, and antioxidant activities compared to the off-season rice samples, which had higher vitamin B3 content. Principal Component Analysis (PCA) and Pearson's correlation were used to determine the relationships among rice qualities and soil physicochemical properties. The rice samples were divided into four groups: Group 1 consisted of rice samples grown in soil with high EC and soluble salts, showing unrelated rice nutrients, TPCs, and antioxidant activities; Group 2 included off-season rice samples grown in soil with high OM that contained high vitamin B3 content; Group 3 contained in-season rice samples grown in soil with high pH that had high energy and fat content, and Group 4 comprised in-season rice samples with high protein, Fe, TPCs, and antioxidant activities, demonstrating moderate to very weak correlations with soil properties. This information can be used to determine the appropriate utilization of fertilizer in soil with different salinity levels and assist in the selection of applicable planting seasons for specific rice qualities.
水稻（Oryza sativa）是一种主食作物，在营养和健康方面发挥着重要作用。其产量主要取决于气候条件。土壤盐分作为干旱导致的一种非生物因素，也会影响水稻的生长、产量和品质。研究人员广泛研究了新培育的耐盐水稻品种和合适的肥料，以提高水稻产量和品质。然而，在不同盐度水平的土壤中种植的季内和季外水稻品种的种植时间对水稻品质（如营养成分、生物活性化合物和与健康相关的特性）的影响仍未得到研究。本研究评估了在具有不同理化性质（电导率提取物（EC）、pH值（pH）、有机质（OM）、有效矿物质（钾和磷）以及可溶性盐（钙、镁、钠和钾））的土壤中种植的38个季内和季外水稻样品的品质（营养成分、酚类物质和抗氧化活性）。结果表明，水稻的营养成分、总酚含量（TPCs）和抗氧化活性受种植季节的影响，而非水稻品种或土壤盐分指标EC。与季外水稻样品相比，季内水稻样品的蛋白质、铁（Fe）、TPCs和抗氧化活性水平更高，而季外水稻样品的维生素B3含量更高。主成分分析（PCA）和皮尔逊相关性分析用于确定水稻品质与土壤理化性质之间的关系。水稻样品被分为四组：第1组由在高EC和可溶性盐土壤中种植的水稻样品组成，其水稻营养成分、TPCs和抗氧化活性之间没有关联；第2组包括在高OM土壤中种植的季外水稻样品，其维生素B3含量高；第3组包含在高pH土壤中种植的季内水稻样品，其能量和脂肪含量高，第4组由具有高蛋白、Fe、TPCs和抗氧化活性的季内水稻样品组成，与土壤性质的相关性为中度至非常弱。这些信息可用于确定在不同盐度水平的土壤中肥料的适当使用，并有助于为特定的水稻品质选择合适的种植季节。
