Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou, China.
Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou, China.
Physiol Plant. 2024 Sep-Oct;176(5):e14549. doi: 10.1111/ppl.14549.
Compensatory effects are common biological phenomena in nature. In this study, we investigated the changes in root nitrogen uptake, root morphological and physiological responses, and changes in the rhizosphere soil microbial communities of indica and japonica rice during a nitrogen deficiency-sensitive period and an effective compensation period with double the nitrogen supply. We conducted a bucket experiment using Suxiu 867 (a japonica rice variety) and Yangxian You 918 (an indica rice variety). Treatments included CK (constant distribution of nitrogen fertilizer at each growth stage, represented by CK867 and CK918) and NDC (nitrogen deficiency in the tillering stage, double nitrogen application in the ear differentiation stage to compensate, represented by NDC867 and NDC918) variations. Both varieties presented the highest δN and N abundances and Ndff (refers to the proportion of nitrogen in a plant's body that comes directly from the fertilizer applied.) in rice under the NDC treatment. Metagenomic sequencing of rhizospheric soil showed that the dominant bacterial groups at the phylum level among each treatment were Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria, Gemmatimonadetes, and Nitrospirae. The rhizosphere of indica rice was more enriched with the microbial communities involved in nitrogen metabolism, which contributed to higher nitrogen utilization efficiency. A correlation-based network was constructed and provides insights into the formation of nitrogen deficiency compensation effects and contributes to the enhancement of nitrogen uptake and utilization efficiency in rice production.
补偿效应是自然界中常见的生物学现象。本研究通过双氮供应，调查了氮缺乏敏感时期和有效补偿时期籼稻和粳稻根系氮吸收、根系形态和生理响应以及根际土壤微生物群落的变化。我们使用 Suxiu 867（粳稻品种）和 Yangxian You 918（籼稻品种）进行了桶实验。处理包括 CK（每个生长阶段氮肥料的恒定分配，以 CK867 和 CK918 表示）和 NDC（分蘖期氮缺乏，在穗分化期双倍氮应用补偿，以 NDC867 和 NDC918 表示）变化。在 NDC 处理下，两种品种的水稻表现出最高的 δN 和 N 丰度和 Ndff（指植物体内氮直接来自施加的肥料的比例）。根际土壤的宏基因组测序表明，各处理中优势细菌门水平的细菌群是放线菌门、变形菌门、绿弯菌门、酸杆菌门、芽单胞菌门和硝化螺旋菌门。籼稻根际土壤中富含参与氮代谢的微生物群落，这有助于提高氮利用效率。构建了基于相关性的网络，为氮亏缺补偿效应的形成提供了见解，并有助于提高水稻生产中氮的吸收和利用效率。
