The imbalance between C and N metabolism during high nitrate supply inhibits photosynthesis and overall growth in maize (Zea mays L.)

0507013 - BFÚ 2020 RIV FR eng J - Journal Article
Saiz-Fernández, I. - De Diego, N. - Brzobohatý, Břetislav - Munoz-Rueda, A. - Lacuesta, M.
The imbalance between C and N metabolism during high nitrate supply inhibits photosynthesis and overall growth in maize (Zea mays L.).
Plant Physiology and Biochemistry. Roč. 120, NOV 2017 (2017), s. 213-222. ISSN 0981-9428
Institutional support: RVO:68081707
Keywords : nitrogen use efficiency * miscanthus x giganteus * c-4 photosynthesis
OECD category: Plant sciences, botany
Impact factor: 2.718, year: 2017
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/abs/pii/S0981942817303327?via%3Dihub

Nitrogen (N) is an important regulator of photosynthetic carbon (C) flow in plants, and an adequate balance between N and C metabolism is needed for comet plant development. However, an excessive N supply can alter this balance and cause changes in specific organic compounds associated with primary and secondary metabolism, including plant growth regulators. In previous work, we observed that high nitrate supply (15 mM) to maize plants led to a decrease in leaf expansion and overall biomass production, when compared with low nitrate supply (5 mM). Thus, the aim of this work is to study how overdoses of nitrate can affect photosynthesis and plant development. The results show that high nitrate doses greatly increased amino acid production, which led to a decrease in the concentration of 2-oxoglutarate, the main source of C skeletons for N assimilation. The concentration of 1-aminocyclopropane-1-carboxylic acid (and possibly its product, ethylene) also rose in high nitrate plants, leading to a decrease in leaf expansion, reducing the demand for photoassimilates by the growing tissues and causing the accumulation of sugars in source leaves. This accumulation of sugars, together with the decrease in 2-oxoglutarate levels and the reduction in chlorophyll concentration, decreased plant photosynthetic rates. This work provides new insights into how high nitrate concentration alters the balance between C and N metabolism, reducing photosynthetic rates and disrupting whole plant development. These findings are particularly relevant since negative effects of nitrate in contexts other than root growth have rarely been studied.
Permanent Link: http://hdl.handle.net/11104/0298114