本文第一作者吴智敏文章解读

期刊：JOURNAL OF AGRICULTURALAND FOOD CHEMISTRY
主题：低氮提升油菜氮利用率新机制
标题：Low Nitrogen Enhances Nitrogen Use Efficiency by Triggering NO3– Uptake and Its Long-Distance Translocation
影响因子：3.412
检测指标：NO₃^-、H⁺
NO₃^-、H⁺流实验方法：油菜幼苗，15mM NO3-处理（CK）和1mM NO3-处理（LN），检测距离根尖600微米的点。
NO₃-、H⁺流实验测试液成份：0.1 mM KNO3, 0.05 mM KCl, 0.15 mM NaCl, 0.05 mM CaCl2, 0.05 mM Mg CaCl2, and 0.3 mM MES ，pH 6.5
作者：湖南农业大学张振华、吴智敏
 

英文摘要

Nitrogen is essential for plant growth andcrop productivity; however, nitrogen use efficiency (NUE) decreases withincreasing N supply, resulting in a waste of resources. Molecular mechanismsunderlying low-nitrogen (LN)-mediated enhancement of NUE are not clear.

We used high-NUE Brassica napus genotype H(Xiangyou 15), low-NUE B. napus genotype L (814), and Arabidopsis mutant aux1to elucidate the mechanism underlying the changes in NUE under different ratesof N fertilizer application. NUE of B. napus increased under LN, which enhancedN uptake ability by regulating root system architecture and plasma membraneH+-ATPase activity; AUX1 was involved in this process.

Additionally, BnNRT1.5 was upregulated andBnNRT1.8 was downregulated under LN, whereby more N was transferred to theshoot through enhanced N transport. Observed changes in photosynthesis under LNwere associated with N assimilation efficiency. Our study provides new insightsinto the mechanisms of plant adaptation to the environment.
 

中文摘要（谷歌机翻译）

氮对植物生长和作物生产力至关重要；然而，随着氮供应的增加，氮利用效率（NUE）降低，导致资源浪费。低氮（LN）介导的NUE增强的分子机制尚不清楚。

我们使用高NUE甘蓝型油菜基因型H（香优15），低NUE B.napus基因型L（814）和拟南芥突变体aux1来阐明在不同氮肥施用量下NUE变化的机制。甘蓝型油菜NUE在LN下增加，通过调节根系结构和质膜H + -ATPase活性提高N吸收能力; AUX1参与了这个过程。

另外，BnNRT1.5被上调并且BnNRT1.8在LN下被下调，由此通过增强的N转运将更多的N转移到芽。观察到的LN下光合作用的变化与N同化效率有关。我们的研究为植物适应环境的机制提供了新的见解。

 

Gas exchange, chlorophyll content, and photosynthetic N use in two contrasting B. napus genotypes for N use efficiency under LN (1 mM NO3− N, black bars) or CK (15 mM NO3− N, white bars) conditions: (a) photosynthetic rate, (b) SPAD, (c) transpiration rate, and (d) photosynthetic N use efficiency (PNUE). The bar height represents the mean, and error bars indicate standard deviation (n = 6). Different letters on bars indicate significant differences based on Tukey’s HSD (p < 0.05). The statistical analysis was performed on different treatments within genotypes.

 

文章链接：https://pubs.acs.org/doi/10.1021/acs.jafc.9b02491

 

本课题组往期NMT文章：

•   V-ATPase and V-PPase at the Tonoplast Affect NO3- Content in Brassica napus by Controlling Distribution of NO3- Between the Cytoplasm and Vacuole
•   Nitrogen Use Efficiency Is Mediated by Vacuolar Nitrate Sequestration Capacity in Roots of Brassica napus
•   NRT1.1-related NH4+ toxicity is associated with balance between NH4+ uptake and assimilation