{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T09:06:27Z","timestamp":1784624787883,"version":"3.55.0"},"reference-count":53,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program Project","award":["2023YFD2301605"],"award-info":[{"award-number":["2023YFD2301605"]}]},{"name":"National Key Research and Development Program Project","award":["2023YFD1501305"],"award-info":[{"award-number":["2023YFD1501305"]}]},{"name":"Heilongjiang Province Modern Agricultural Industry Technology Collaborative Innovation System Project","award":["2026"],"award-info":[{"award-number":["2026"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Nitrogen (N) fertilizer regulates leaf photosynthesis and dry matter production in rice, and extensive genotypic differences in N responsiveness exist among cold-region japonica rice cultivars. A two-year field experiment was conducted in the city of Jiamusi, Heilongjiang Province, during 2023\u20132024, using two representative japonica cultivars: the small-panicle cultivar Longjing 47 (LJ47) and the large-panicle cultivar Longjing 3010 (LJ3010). A split-plot design was adopted with four N application rates (0, 110, 138, and 166 kg N\u00b7ha\u22121) and four basal\u2013tiller to panicle\u2013grain N ratios (10:0, 8:2, 7:3, and 6:4). The results showed that increasing N supply significantly enhanced SPAD values, photosynthetic capacity, leaf area index, and total dry matter accumulation in both cultivars. LJ47 maintained high photosynthetic capacity under moderate N supply, whereas LJ3010 required higher N input to sustain superior photosynthetic performance. From heading to maturity, dry matter accumulation, photosynthetic potential, crop growth rate, net assimilation rate, N uptake, and grain yield all increased with an increasing ratio of panicle\u2013grain N fertilizer, with more pronounced improvements observed in LJ3010. LJ47 achieved optimal physiological performance and grain yield at 138 kg N\u00b7ha\u22121 (moderate N), with no further promotion under high-N supply. In contrast, LJ3010 required 166 kg N\u00b7ha\u22121 (high-N) to maintain photosynthetic advantages and achieve higher grain yield in the late growth stage. Increasing the proportion of basal\u2013tiller N fertilizer favored the source sink balance of LJ47, while increasing panicle\u2013grain topdressing delayed leaf senescence and promoted post-heading dry matter translocation in LJ3010. For a target grain yield of 9 t\u00b7ha\u22121, the recommended N rate is 138 kg\u00b7ha\u22121 with a basal\u2013tiller to panicle\u2013grain N ratio of 8:2\u20137:3 for LJ47, and 166 kg\u00b7ha\u22121 with a ratio of 7:3\u20136:4 for LJ3010. This study provides a theoretical basis and data reference for the formulation of precise N fertilization strategies that match fertilizer management with rice cultivar characteristics in cold regions.<\/jats:p>","DOI":"10.3390\/plants15142217","type":"journal-article","created":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T08:14:27Z","timestamp":1784621667000},"page":"2217","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of N Application Rates and Ratios on Photosynthetic Characteristics and Dry Matter Production of Different Rice Varieties"],"prefix":"10.3390","volume":"15","author":[{"given":"Jinghong","family":"Ji","sequence":"first","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingfang","family":"Xue","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Jiamusi Field Comprehensive Scientific Observation and Research Station, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"},{"name":"Scientific Observation and Experimental Station for Cold Damage of Japonica Rice in Cold Regions, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7115-9500","authenticated-orcid":false,"given":"Xingzhu","family":"Ma","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongsheng","family":"Cai","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Jiamusi Field Comprehensive Scientific Observation and Research Station, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"},{"name":"Scientific Observation and Experimental Station for Cold Damage of Japonica Rice in Cold Regions, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuangquan","family":"Liu","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyu","family":"Hao","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5321-035X","authenticated-orcid":false,"given":"Yu","family":"Zheng","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue","family":"Zhao","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Scientific Observation and Research Station of Soil Quality, Key Laboratory of Black Soil Protection and Utilization, Ministry of Agriculture and Rural Areas, Harbin 150086, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuqi","family":"Xia","sequence":"additional","affiliation":[{"name":"Institute of Life Sciences, Heilongjiang Bayi Agricultural University, Daqing 163319, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuqiang","family":"Chen","sequence":"additional","affiliation":[{"name":"Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China"},{"name":"Jiamusi Field Comprehensive Scientific Observation and Research Station, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"},{"name":"Scientific Observation and Experimental Station for Cold Damage of Japonica Rice in Cold Regions, Ministry of Agriculture and Rural Affairs, Jiamusi 154026, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"key":"ref_1","unstructured":"National Bureau of Statistics (2025). China Statistical Year Book 2024, China Statistics Press."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1007\/BF01880183","article-title":"Behaviour of photosynthetic products associated with growth and grain production in the rice plant","volume":"26","author":"Lian","year":"1967","journal-title":"Plant Soil"},{"key":"ref_3","first-page":"5","article-title":"Studies on Translocation and Distribution of Photosynthate in Rice Variety Yuexianzhan with High Harvest Index","volume":"21","author":"He","year":"2000","journal-title":"J. South China Agric. Univ."},{"key":"ref_4","first-page":"1305","article-title":"The relationship between the enhancement of rice grain yield and photosynthesis","volume":"36","author":"Chang","year":"2024","journal-title":"Chin. Bull. Life Sci."},{"key":"ref_5","first-page":"1650","article-title":"N fertilizer reduction potential in the main rice producing region of black soil in Northeast China","volume":"77","author":"Yin","year":"2022","journal-title":"Acta Geogr. Sin."},{"key":"ref_6","first-page":"140","article-title":"The Extension of Deep Side Fertilizing Technology in Rice Production\u2014Take Heilongjiang as an Example","volume":"37","author":"Zhou","year":"2021","journal-title":"Chin. Agric. Sci. Bull."},{"key":"ref_7","first-page":"1182","article-title":"A new method for determining economical N application rate based on yield-response function of rice grain","volume":"28","author":"Peng","year":"2022","journal-title":"J. Plant Nutr. Fertil."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1420","DOI":"10.1038\/s41467-025-56752-7","article-title":"Natural variation of OsWRKY23 drives difference in nitrate use efficiency between indica and japonica rice","volume":"16","author":"Zhang","year":"2025","journal-title":"Nat. Commun."},{"key":"ref_9","first-page":"954","article-title":"Characteristics of N Nutrition in Rice Based on High N Input and Genotype Differences","volume":"55","author":"Chen","year":"2023","journal-title":"Soils"},{"key":"ref_10","first-page":"1113","article-title":"Mechanism of High N Uptake Efficiency in Indica-japonica Hybrid Rice","volume":"52","author":"Chen","year":"2025","journal-title":"Soils"},{"key":"ref_11","first-page":"1399","article-title":"Study on Population Construction and Its Super- high Yield Characteristics of Japonica Super Rice in Cold Region","volume":"28","author":"Chen","year":"2015","journal-title":"Southwest China J. Agric. Sci."},{"key":"ref_12","first-page":"796","article-title":"Differences of N uptake, utilization and translocation between indica and japonica super rice","volume":"20","author":"Gong","year":"2014","journal-title":"J. Plant Nutr. Fertil."},{"key":"ref_13","first-page":"1","article-title":"Studies on The Basis of Unfulfilled Grain of Rice Plant in Cold Region IV The Relationship Between Yield Components of Different Cultivars (Lines) and Unfulfilled Grain","volume":"5","author":"Wang","year":"2001","journal-title":"Hei Longjiang Agric. Sci."},{"key":"ref_14","first-page":"312","article-title":"Effects of N utilization differences among rice varieties on grain yield","volume":"56","author":"Qi","year":"2025","journal-title":"Trans. Chin. Soc. Agric. Mach."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"869","DOI":"10.2134\/agronj2001.934869x","article-title":"Performance of site-specific nutrient management for irrigated rice in Southeast China","volume":"93","author":"Wang","year":"2001","journal-title":"Agron. J."},{"key":"ref_16","first-page":"19","article-title":"The impact of N fertilizer management on rice growth and yield","volume":"44","author":"Yuan","year":"2024","journal-title":"Agric. Eng. Technol."},{"key":"ref_17","first-page":"147","article-title":"Effects of Straw Returning and N Fertilizer Management on Photosynthetic Characteristics and Yield of Rice in Cold Region","volume":"2025","author":"Hu","year":"2025","journal-title":"Crops"},{"key":"ref_18","first-page":"945","article-title":"Effects of Different Irrigation and N Application Methods on Photosynthetic Characteristics, Agronomic Traits and N Use of Rice","volume":"46","author":"Zhang","year":"2024","journal-title":"J. Jilin Agric. Univ."},{"key":"ref_19","unstructured":"Zhang, H. (2009). Effects of N Application at Later Stage on Photosynthetic Characteristics of Rice After Heading in Cold Area. [Master\u2019s Thesis, Northeast Agricultural University]."},{"key":"ref_20","first-page":"1","article-title":"Study on Optimum Fertilization Rate and Suitable Proportion of Japonica Super Rice in Cold Region","volume":"47","author":"Chen","year":"2022","journal-title":"J. Northeast Agric. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"485","DOI":"10.3724\/SP.J.1006.2025.42024","article-title":"Analysis of agronomic and physiological indicators of rice yield and grain quality under N fertilization management","volume":"51","author":"Qin","year":"2025","journal-title":"Acta Agron. Sin."},{"key":"ref_22","first-page":"1089","article-title":"Differences in Photosynthetic Characteristics and Yield Components of rice Populations at Different Yield levels","volume":"39","author":"Yang","year":"2023","journal-title":"Jiangsu J. Agric. Sci."},{"key":"ref_23","first-page":"123","article-title":"Effects of Different Rational Ratio of N,P,K Fertilizer and Amount of N Fertilizer on Photosynthesis Character and Yield of Rice","volume":"30","author":"Peng","year":"2004","journal-title":"J. Hunan Agric. Univ. (Nat. Sci.)"},{"key":"ref_24","first-page":"149","article-title":"Effects of controlled-release urea on agronomic traits, grain yield and N use efficiency of cold-region rice","volume":"2025","author":"Ji","year":"2025","journal-title":"Crops"},{"key":"ref_25","first-page":"684","article-title":"Genotypic variation in N utilization of cold-region rice","volume":"56","author":"Qi","year":"2025","journal-title":"Trans. Chin. Soc. Agric. Mach."},{"key":"ref_26","first-page":"1421","article-title":"25-year changes in rice NUE in Heilongjiang","volume":"30","author":"Zheng","year":"2024","journal-title":"Plant Nutr. Fertil. Sci."},{"key":"ref_27","first-page":"301","article-title":"Grain-filling Characteristics of Two Differentpanicle Type Rice Cultivars in Heilongjiang Province","volume":"17","author":"Xue","year":"2016","journal-title":"Agric. Sci. Technol."},{"key":"ref_28","first-page":"87","article-title":"Study on the Material Production Characteristics of High Yield Population of Different Types of Rice Variety in Cold Region","volume":"31","author":"Cai","year":"2025","journal-title":"China Rice"},{"key":"ref_29","first-page":"44","article-title":"Effect of Amount and Proportion of N Application on Panicle Traits and Yield of Different Types of Rice","volume":"2019","author":"Chen","year":"2019","journal-title":"Hei Longjiang Agric. Sci."},{"key":"ref_30","first-page":"2162","article-title":"Effects of N Level on Source-Sink Relationship of Cassava","volume":"29","author":"Jiang","year":"2016","journal-title":"Southwest China J. Agric. Sci."},{"key":"ref_31","first-page":"173","article-title":"Effects of N application on the synergistic senescence of rice source and sink","volume":"58","author":"Liu","year":"2022","journal-title":"Plant Physiol. J."},{"key":"ref_32","first-page":"252","article-title":"Effect of Different Fertilizer-N Application Rate on Source-sink Characteristics of Super Hybrid Rice","volume":"26","author":"Feng","year":"2010","journal-title":"Chin. Agric. Sci. Bull."},{"key":"ref_33","first-page":"82","article-title":"The Effect of Different N Applied Levels on Source-sink Characteristics of Hybrid Rice Maintain Lines","volume":"30","author":"Yang","year":"2014","journal-title":"Chin. Agric. Sci. Bull."},{"key":"ref_34","first-page":"1","article-title":"Study on photosynthetic producing and nitrogen metabolism characteristics of high-yield and high-efficiency rice varieties","volume":"46","author":"Zhang","year":"2025","journal-title":"J. Yangzhou Univ. (Agric. Life Sci. Ed.)"},{"key":"ref_35","first-page":"185","article-title":"Fundamental Features of Source-Sink Characters and Their Regulation in High N Efficiency Rice Lines","volume":"31","author":"Chen","year":"2017","journal-title":"Chin. J. Rice Sci."},{"key":"ref_36","first-page":"1","article-title":"Investigation on The Population Quality of High Yield and Its Optimizing Control Programme in Rice","volume":"6","author":"Ling","year":"1993","journal-title":"Sci. Agric. Sin."},{"key":"ref_37","first-page":"2286","article-title":"Effects of the Site-Specific N Management on Yield and Dry Matter Accumulation of Rice in Cold Areas of Northeastern China","volume":"39","author":"Peng","year":"2006","journal-title":"Sci. Agric. Sin."},{"key":"ref_38","first-page":"609","article-title":"Effects of irrigation and N management on N use efficiency and yield of hybrid rice cultivated in ditches under no-tillage","volume":"22","author":"Zhao","year":"2016","journal-title":"J. Plant Nutr. Fertil."},{"key":"ref_39","first-page":"656","article-title":"Effects of N Applied at Different Stages on Photosynthetic Traits of Flag Leaf and Rice Quality","volume":"24","author":"Zhang","year":"2008","journal-title":"Jiangsu J. Agric. Sci."},{"key":"ref_40","first-page":"222","article-title":"Source-Sink Relationship during Grain Filling in Response to Leaf-cutting Treatment for Heavy Panicle Rice Cultivars","volume":"41","author":"Chen","year":"2020","journal-title":"Chin. J. Agrometeorol."},{"key":"ref_41","first-page":"1","article-title":"Studies on \u201cGrain-Leaf ration\u201d of Population and Cultural Approaches of High Yield in Rice Plants","volume":"3","author":"Ling","year":"1986","journal-title":"Sci. Agric. Sin."},{"key":"ref_42","first-page":"317","article-title":"Effects of climate change on the yield of major grain crops and its adaptation measures in China","volume":"26","author":"Zhao","year":"2019","journal-title":"Res. Soil Water Conserv."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1342","DOI":"10.3724\/SP.J.1006.2010.01342","article-title":"Preliminary study on parameters of precise and quantitative N application in rice varieties with different growth period durations","volume":"36","author":"Yin","year":"2010","journal-title":"Acta Agron. Sin."},{"key":"ref_44","first-page":"1129","article-title":"Responses of ammonia volatilization to nitrogen application amount in typical double cropping paddy fields in Hunan Province","volume":"19","author":"Zhu","year":"2013","journal-title":"J. Plant Nutr. Fertil."},{"key":"ref_45","first-page":"569","article-title":"Nitrogen consumption of double-season hybrid rice and influence factors in South China","volume":"13","author":"Zhong","year":"2007","journal-title":"Plant Nutr. Fertil. Sci."},{"key":"ref_46","unstructured":"Ling, Q. (2000). Crop Population Quality, Shanghai Scientific & Technical Publishers."},{"key":"ref_47","first-page":"2092","article-title":"Analysis of fertilizer application and its reduction potential in paddy fields of Heilongjiang Province","volume":"52","author":"Peng","year":"2019","journal-title":"Sci. Agric. Sin."},{"key":"ref_48","first-page":"4143","article-title":"Difference in N Responses and N Efficiency of Different Paddy Soils in Southern and Northern China Under the Same Climatic Condition","volume":"54","author":"Huang","year":"2021","journal-title":"Sci. Agric. Sin."},{"key":"ref_49","first-page":"249","article-title":"Improvement and validation of theoretical N rate (TNR): Discussing the methods for N fertilizer recommendation","volume":"52","author":"Ju","year":"2015","journal-title":"Acta Pedol. Sin."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1682","DOI":"10.2134\/agronj15.0013","article-title":"Crop management for increasing rice yield and N use efficiency in Northeast China","volume":"107","author":"Peng","year":"2015","journal-title":"Agron. J."},{"key":"ref_51","first-page":"1","article-title":"Effects of N Application on Yield, Quality and Fertilizer Efficiency of Japonica Rice in Northern China","volume":"49","author":"Ji","year":"2024","journal-title":"J. Northeast Agric. Sci."},{"key":"ref_52","first-page":"987","article-title":"Spatial-temporal variation of N balance and partial factor productivity of N in rice region of China over the past 30 years","volume":"26","author":"Huang","year":"2020","journal-title":"J. Plant Nutr. Fertil."},{"key":"ref_53","unstructured":"Bi, T. (2023). Study on Optimal Nitrogen Rate, Nitrogen Fate and Loss Characteristics in Cold Rice Fields. [Ph.D. Thesis, Northeast Agricultural University]."}],"container-title":["Plants"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/14\/2217\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T08:56:12Z","timestamp":1784624172000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/14\/2217"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,21]]},"references-count":53,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["plants15142217"],"URL":"https:\/\/doi.org\/10.3390\/plants15142217","relation":{},"ISSN":["2223-7747"],"issn-type":[{"value":"2223-7747","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,21]]}}}