The physiological response of photosynthesis to nitrogen deficiency

• Published in: Plant physiology and biochemistry 2021-01, Vol.158, p.76-82
• Main Authors: Mu, Xiaohuan, Chen, Yanling
• Format: Article
• Language: English
• Subjects: Bioenergetics; Carbon Dioxide; Light-harvesting proteins; Mesophyll Cells; Nitrogen; Nitrogen - physiology; Nitrogen allocation; Photosynthesis; Photosynthetic enzymes; Plant Leaves - physiology; Plant Stomata; Stress, Physiological; Thylakoids
• ISSN: 0981-9428; 1873-2690
• DOI: 10.1016/j.plaphy.2020.11.019

Nitrogen (N), as a macro-element, plays a vital role in plant growth and development. N deficiency affects plant productivity by decreasing photosynthesis, leaf area and longevity of green leaf. To date, many studies have reported that the relationship between photosynthesis and N supply. Here, we summarized the physiological response of photosynthesis to N deficiency in leaf structure and N allocation within the leaf. In serious N stress, photosynthetic rate decreases for almost all plants. The reasons as follows:(1) reducing stomatal conductance of mesophyll cell (gs) and bundle sheath cells (gbs) which influences intercellular CO2 concentration; (2) reducing the content of bioenergetics and light-harvesting protein which inhibits electron transport rate and increase the light energy dissipated as heat; (3) reducing the content and/or activity of photosynthetic enzymes which reduces carboxylation rate. During reproductive stage, N stress induces plant senescence and N components degradation, especially photosynthetic enzymes and thylakoid N, and thus reduces photosynthesis. To keep high grain yield in low N deficiency, we should choose the genotype with higher N allocation within bioenergetics and lower degradation of photosynthetic enzymes. This review provides a generalized N allocation in response to N stress and gives a new prospect for breeding N-efficient genotypes. •Nitrogen plays a vital role in plant growth and productivity.•Photosynthesis provides the foundation for essentially all life.•Nitrogen supply has a significant effect on photosynthesis by influencing leaf structure and nitrogen allocation within leaf.•In nitrogen stress, plants tend to invest more nitrogen into bioenergetics to keep high electron transport rate.