冬小麦灌浆过程中旗叶氮素再分配及其与TaATG8表达的关系

doi:10.1016/j.jia.2024.12.024

摘要/Abstract

摘要： 氮素是小麦（Triticum aestivum L.）生长和产量的重要营养元素，特别是在灌浆期，大部分氮素从营养器官重新分配到籽粒，对产量有显著影响。然而，氮素从营养器官向籽粒转运的具体时间段及其与旗叶衰老的相关性仍不清楚。本研究以冬小麦品种‘西农511’为试验材料，在田间条件下设置了两种氮肥处理：常规施氮（240 kg ha⁻¹ [N₂₄₀]）和不施氮（0 kg ha⁻¹ [N₀]）。结果显示，小麦旗叶中的氮素积累在7-14天达到峰值，氮含量为4.55%，随后氮素开始向籽粒重新分配。在21-35天内，旗叶中的氮含量减少了56%，而籽粒中的氮含量增加了51%。旗叶的相对叶绿素含量、光合速率、游离氨基酸浓度和可溶性蛋白含量在7-14天达到峰值，表明氮素从旗叶向籽粒运输。与N₀处理相比，施氮显著提高了旗叶氮素再分配速率20%，减少了21%的活性氧（ROS）积累，并延缓了旗叶衰老。在缺氮条件下，自噬过程提前被诱导，自噬相关基因（TaATG8）的表达增加了5-7倍，这表明通过调控自噬途径并增强自噬活性可以优化氮肥利用效率。本研究表明，氮素从营养器官向籽粒的再分配启动了叶片的衰老过程，并与自噬相关基因的表达密切相关。

Abstract:

Nitrogen is a key nutrient for wheat (Triticum aestivum L.) growth and yield, particularly during the grain-filling stage, where most nitrogen is redistributed from vegetative organs to the grain, significantly influencing yield. However, it remains unclear during which period the nitrogen translocation from the vegetative phase to grain maturation occurs and how it correlates with flag leaf senescence. In this study, a field experiment was conducted using the winter wheat cultivar ‘Xinong 511’ under two nitrogen fertilizer treatments: regular nitrogen supply (240 kg ha^–1 (N₂₄₀)) and no nitrogen supply (0 kg ha^–1 (N₀)). The results revealed that nitrogen accumulation in wheat flag leaves peaked at 7–14 days, with a nitrogen content 4.55%, after which nitrogen was redistributed to the grains. Nitrogen content in flag leaves decreased by 56% during 21–35 days, while that in the grains increased by 51%. The plant analysis development value (relative chlorophyll content), photosynthetic rate, free amino acid concentration, and soluble protein content in flag leaves peaked at 7–14 days, indicating nitrogen transportation from the flag leaves to the grains. Nitrogen application significantly increased the nitrogen remobilization rate in flag leaves by 20% compared with that of N₀, reduced reactive oxygen species accumulation by 21%, and delayed flag leaf senescence. Under nitrogen deficiency, autophagy was induced earlier, with a 5–7-fold increase in the expression of autophagy-related genes (TaATG8), suggesting that regulation of the autophagy pathway and enhancement of autophagy activity can optimize nitrogen fertilization. Our study demonstrates that the remobilization of nitrogen from vegetative parts to grains initiates leaf senescence and is closely correlated with the expression of autophagy-related genes.

Key words: winter wheat , senescence , autophagy , nitrogen redistribution , grain-filling stage

Guoming Li, Xiaotian Ren, Shengyan Pang, Changjie Feng, Yuxi Niu, Yanjie Qu, Changhong Liu, Xiang Lin, Dong Wang. 冬小麦灌浆过程中旗叶氮素再分配及其与TaATG8表达的关系[J]. Journal of Integrative Agriculture, 2026, 25(4): 1433-1442.

Guoming Li, Xiaotian Ren, Shengyan Pang, Changjie Feng, Yuxi Niu, Yanjie Qu, Changhong Liu, Xiang Lin, Dong Wang. Nitrogen redistribution during the grain-filling stage and its correlation with senescence and TaATG8 expression in leaves of winter wheat[J]. Journal of Integrative Agriculture, 2026, 25(4): 1433-1442.

参考文献

Avila-Ospina L, O’Neill C M, Gutierrez R A, Vorster B J. 2014. Autophagy promotes leaf senescence and cell death in Arabidopsis. Journal of Experimental Botany, 65, 3921–3933.

Balkcom K S, Burmester C H. 2015. Tillage practices for wheat in the southeastern United States. Agronoy Journal, 107, 1673–1679.

Bly A G, Woodard H J. 2003. Foliar nitrogen application timing influence on grain yield and protein concentration of hard red winter and spring wheat. Agronomy Journal, 95, 335–338.

Breeze E, Harrison E, McHattie S, Hughes L, Hickman R, Hill C, Kiddle S, Kim Y S, Penfold C A, Jenns D, Zhang C, Morris K, Jenner C, Jackson S, Thomas B, Tabrett A, Legaie R, Moore J D, Wild D L, Ott S, et al. 2009. High-resolution temporal profiling of transcripts during Arabidopsis leaf senescence reveals a distinct chronology of processes and regulation. The Plant Cell, 23, 873–894.

Chen X, Yang Y, Zhang C, Liu X, Zeng L, Zhan J, Chen H, Luo J, Yang W. 2019. ATG8-interacting proteins regulate autophagosome formation in Arabidopsis. Journal of Experimental Botany, 70, 2885–2898.

Christopher J T, Manschadi A M, Hammer G L, Borrell A K. 2008. Developmental and physiological traits associated with high yield and stay-green phenotype in wheat. Australian Journal of Agricultural Research, 59, 354–364.

Diaz C, Lemaire G, Onillon B, Gosse G, Chartier M, Allirand J M. 2005. Nitrogen nutrition and delay of senescence in a Lolium perenne L. crop: N fluxes and plant productivity. Annals of Botany, 87, 225–234.

Fageria N K, Baligar V C. 2005. Enhancing nitrogen use efficiency in crop plants. Advances in Agronomy, 88, 97–185.

Gregersen P L, Culetic A, Boschian L, Krupinska K. 2013. Plant senescence and crop productivity. Plant Molecular Biology, 82, 603–622.

Görlach A, Klappa P, Kietzmann T. 2015. The cross-talk between reactive oxygen species and calcium signaling. Antioxidants & Redox Signaling, 22, 935–952.

Guiboileau A, Avila-Ospina L, Yoshimoto K, Soulay F, Azzopardi M, Marmagne A, Masclaux-Daubresse C. 2013. Physiological and metabolic consequences of autophagy deficiency for the management of nitrogen and protein resources in Arabidopsis leaves depending on nitrate availability. New Phytologist, 199, 683–694.

Huang Y, Zhang W, He S, Cao K, Yu Z, Chen F. 2013. Influence of nitrogen fertilization on the protein content, amino acid composition, and processing quality of winter wheat. Journal of Plant Nutrition and Soil Science, 176, 409–417.

Islam F, Wang J, Javed T, Zhou W, Shi Y, Ren C, Yun X, Hu X, Zhang G. 2016. Autophagy enhances the tolerance of wheat (Triticum aestivum L.) to salt stress. Plant Physiology and Biochemistry, 109, 155–166.

Jajic I, Sarna T, Strzalka K. 2015. Senescence, stress, and reactive oxygen species. Plant Physiology and Biochemistry, 97, 53–66.

Kamal N M, Othman R Y, Harun A R. 2019. Chlorophyll content and photosynthesis capacity decrease with the progression of senescence in wheat. Journal of Plant Physiology, 240, 152991.

Krautler B. 2016. Chlorophyll breakdown and the phyllobilins. Accounts of Chemical Research, 49, 181–190.

Lawlor D W, Lemaire G. 2001. Carbon and nitrogen assimilation in relation to yield: Mechanisms are the key to understanding production systems. Journal of Experimental Botany, 52, 1761–1771.

Li F, Vierstra R D. 2012. Autophagy: A multifaceted intracellular system for bulk and selective recycling. Trends in Plant Science, 17, 526–537.

Lin Y, Zhang X, Feng X, Liu Y, Gao L, Zhang X. 2021. Autophagy enhances hypoxia tolerance in wheat roots by removing reactive oxygen species. Plant Science, 311, 110991.

Lim P O, Kim H J, Nam H G. 2007. Leaf senescence. Annual Review of Plant Biology, 58, 115–136.

Mao H, Sun J, Cao Y, Xie J. 2017. Prolonging leaf senescence via upregulating GmWRKY54 improves the yield of soybean. Plant Biotechnology Journal, 15, 964–975.

Masclaux-Daubresse C, Chardon F. 2010. Nitrogen recycling and leaf senescence. Journal of Experimental Botany, 61, 2483–2492.

Masclaux-Daubresse C, Chardon F. 2011. Exploring nitrogen remobilization for seed filling using natural variation in Arabidopsis thaliana. Journal of Experimental Botany, 62, 2131–2142.

Masclaux-Daubresse C, Reisdorf-Cren M, Orsel M, Chardon F. 2008. Nitrogen remobilization during leaf senescence: Lessons from Arabidopsis to crops. Journal of Experimental Botany, 59, 927–934.

Pérez F J, Ribera A E, Zúñiga G E. 2012. Reactive oxygen species and autophagy: A key role for hydroxyl radical in determining the fate of peroxisomes. Plant Signaling & Behavior, 7, 944–948.

Pottier M, Dumont J, Masclaux-Daubresse C, Thomine S. 2014. Autophagy protects Arabidopsis from heavy metal stress by remodeling vacuoles. Plant Physiology, 166, 911–920.

Shah W A, Habib A, Ullah S. 2017. Nitrogen application improves growth and yield attributes of wheat under varying irrigation regimes. Journal of Plant Nutrition, 40, 1823–1831.

Sharma N, Singh V, Sharma J D. 2003. Relative contribution of photosynthates to grain filling in wheat genotypes under normal and late sown conditions. Journal of Agronomy and Crop Science, 189, 108–114.

Signorelli S, Agostoni P, Paredes-Paliz K. 2008. Nitrogen starvation-induced oxidative stress in marine cyanobacterium Synechococcus PCC7942: A role for glutathione biosynthesis. Journal of Photochemistry and Photobiology (B: Biology), 91, 150–156.

Sima H, Liu Y, Xu D, Deng X. 2011. Study on the mechanism of reactive oxygen species and antioxidant system in wheat leaves under cadmium stress. Journal of Agro-Environment Science, 30, 1656–1662.

Sorin C, Bussell J D, Camus I, Ljung K, Kowalczyk M, Geiss G, McKhann H, Garcion C, Vaucheret H, Sandberg G, Bellini C. 2016. Auxin and light control of adventitious rooting in Arabidopsis require ARGONAUTE1. The Plant Cell, 17, 1343–1359.

Srivalli B, Sharma G, Khanna-Chopra R. 2009. Tightly controlled senescence-associated genes under nitrogen deficiency improve yield and nitrogen use efficiency in wheat. Journal of Plant Physiology, 166, 852–865.

Stamp P, Herzog H. 1976. The role of the flag leaf in wheat yield formation. Journal of Agronomy and Crop Science, 139, 47–54.

Terrile M C, Mercado-Blanco J, Rodríguez M J, Martínez-Sierra M. 2017. Involvement of nitric oxide in the beneficial effects of hormonal pre-treatments on plant stress tolerance. Frontiers in Plant Science, 8, 1360.

Wang B, Chen X, Tian J, Zhang Y. 2016. The role of nitrogen fertilization on photosynthesis and grain yield of wheat genotypes under drought conditions. Plant Science, 252, 254–263.

Wang S Y, Zheng W, Galleta G J. 1990. Influence of plant age and fruiting on leaf photosynthesis and dark respiration in strawberry (Fragaria×ananassa). Journal of Horticultural Science, 65, 721–726.

Wang X, Guo H, Liu J. 2017. ATG genes promote nitrogen mobilization and improve yield in Arabidopsis under nitrogen-deficient conditions. The Plant Cell, 29, 1455–1469.

Wang Y, Schippers J H. 2019. Autophagy and leaf senescence. Plant Science, 283, 102–109.

Zakari A, Tian X, Lu Q, Yousaf H, Wen X. 2019. The role of nitrogen in regulating leaf senescence and improving yield and seed quality in oil crops: A review. Agronomy, 9, 510.

Zaveri E, Lobell D B. 2019. The role of nitrogen in closing wheat yield gaps across the globe. Global Environmental Change, 56, 21–27.