Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina.
College of Agronomy, Henan Agricultural University, ZhengzhouChina.
J Exp Bot. 2021 May 28;72(12):4435-4456. doi: 10.1093/jxb/erab153.
The effective use of available nitrogen (N) to improve crop grain yields provides an important strategy to reduce environmental N pollution and promote sustainable agriculture. However, little is known about the common genetic basis of N use efficiency (NUE) at varying N availability. Two wheat (Triticum aestivum L.) cultivars were grown in the field with high, moderate, and low N supply. Cultivar Zhoumai 27 outperformed Aikang 58 independent of the N supply and showed improved growth, canopy leaf area index, flag leaf surface area, grain number, and yield, and enhanced NUE due to both higher N uptake and utilization efficiency. Further, transcriptome and proteome analyses were performed using flag leaves that provide assimilates for grain growth. The results showed that many genes or proteins that are up- or down-regulated under all N regimes are associated with N and carbon metabolism and transport. This was reinforced by cultivar differences in photosynthesis, assimilate phloem transport, and grain protein/starch yield. Overall, our study establishes that improving NUE at both high and low N supply requires distinct adjustments in leaf metabolism and assimilate partitioning. Identified key genes/proteins may individually or concurrently regulate NUE and are promising targets for maximizing crop NUE irrespective of the N supply.
有效利用可用氮（N）以提高作物的粮食产量，为减少环境 N 污染和促进可持续农业提供了一个重要策略。然而，对于不同 N 有效性下 N 使用效率（NUE）的常见遗传基础，人们知之甚少。两个小麦（Triticum aestivum L.）品种在高、中、低 N 供应条件下进行了田间种植。无论 N 供应如何，周麦 27 都优于矮抗 58，表现出更好的生长、冠层叶面积指数、旗叶表面积、粒数和产量，并通过提高氮吸收和利用效率来提高 NUE。此外，使用为籽粒生长提供同化产物的旗叶进行了转录组和蛋白质组分析。结果表明，许多在所有 N 处理下上调或下调的基因或蛋白质与氮和碳代谢及运输有关。这与光合作用、同化产物韧皮部运输和籽粒蛋白质/淀粉产量的品种差异相吻合。总的来说，我们的研究表明，在高氮和低氮供应下提高 NUE 需要在叶片代谢和同化产物分配上进行不同的调整。鉴定出的关键基因/蛋白质可能单独或共同调节 NUE，是提高作物 NUE 的有前途的靶点，而与 N 供应无关。
