Main conclusion

Overexpression of OsNRT1.1A promotes early heading and increases the tolerance in wheat under nitrogen deficiency conditions.

Abstract

The application of inorganic nitrogen (N) fertilizers is a major driving force for crop yield improvement. However, the overuse of fertilizers significantly raises production costs and leads to environmental problems, making it critical to enhance crop nitrogen use efficiency (NUE) for the sake of sustainable agriculture. In this study, we created a series of transgenic wheat lines carrying the rice OsNRT1.1A gene, which encodes a nitrate transporter, to investigate its possible application in improving NUE in wheat. The transgenic wheat exhibited traits such as early maturation that were highly consistent with the overexpression of OsNRT1.1A in Arabidopsis and rice. However, we also observed that overexpression of the OsNRT1.1A gene in wheat can facilitate the growth of roots under low N conditions but has no effect on other aspects of growth and development under normal N conditions. Thus, it may lead to the improvement of wheat low N tolerance,which is different from the effects reported in other plants. A field trial analysis showed that transgenic wheat exhibited increased grain yield per plant under low N conditions. Moreover, transcriptome analysis indicated that OsNRT1.1A increased the expression levels of N uptake and utilization genes in wheat, thereby promoting plant growth under low N conditions. Taken together, our results indicated that OsNRT1.1A plays an important role in improving NUE in wheat with low N availability.

中文翻译：

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水稻OsNRT1.1A/OsNPF6.3过表达提高低氮条件下小麦氮素利用效率

主要结论

OsNRT1.1A的过表达可促进早抽穗并提高小麦在缺氮条件下的耐受性。

抽象的

无机氮肥的施用是提高作物产量的主要动力。然而，肥料的过度使用显着提高了生产成本并导致环境问题，因此提高作物氮肥利用效率（NUE）对于可持续农业至关重要。在这项研究中，我们创建了一系列携带水稻OsNRT1.1A基因（编码硝酸盐转运蛋白）的转基因小麦品系，以研究其在提高小麦 NUE 方面的可能应用。转基因小麦表现出早熟等性状，与拟南芥和水稻中OsNRT1.1A的过表达高度一致。然而，我们也观察到OsNRT1.1A基因在小麦中的过表达可以促进低氮条件下根的生长，但在正常氮条件下对生长发育的其他方面没有影响。因此，它可能会导致小麦低氮耐受性的提高，这与其他植物报道的效果不同。田间试验分析表明，转基因小麦在低氮条件下表现出增加的单株籽粒产量。此外，转录组分析表明，OsNRT1.1A增加了小麦氮吸收和利用基因的表达水平，从而促进低氮条件下的植物生长。综上所述，我们的结果表明，OsNRT1.1A 在提高低氮利用率小麦的 NUE 方面发挥着重要作用。