Photosynthetic decline in aging perennial grass is not fully explained by leaf nitrogen
Date
2022-12-08
Authors
Tejera, Mauricio
Boersma, Nicholas N.
Archontoulis, Sotirios V.
Miguez, Fernando E.
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
© The Author(s) 2022
Abstract
Aging in perennial plants is traditionally observed in terms of changes in end-of-season biomass; however, the driving phenological and physiological changes are poorly understood. We found that 3-year-old (mature) stands of the perennial grass Miscanthus×giganteus had 19–30% lower Anet than 1-year-old M.×giganteus (juvenile) stands; 10–34% lower maximum carboxylation rates of Rubisco and 34% lower light-saturated Anet (Asat). These changes could be related to nitrogen (N) limitations, as mature plants were larger and had 14–34% lower leaf N on an area basis (Na) than juveniles. However, N fertilization restored Na to juvenile levels but compensated only 50% of the observed decline in leaf photosynthesis with age. Comparison of leaf photosynthesis per unit of leaf N (PNUE) showed that mature stands had at least 26% lower PNUE than juvenile stands across all N fertilization rates, suggesting that other factors, besides N, may be limiting photosynthesis in mature stands. We hypothesize that sink limitations in mature stands could be causing feedback inhibition of photosynthesis which is associated with the age-related decline in photosynthesis.
Series Number
Journal Issue
Is Version Of
Versions
Series
Academic or Administrative Unit
Type
article
Comments
This article is published as Mauricio Tejera, Nicholas N Boersma, Sotirios V Archontoulis, Fernando E Miguez, Andy VanLoocke, Emily A Heaton, Photosynthetic decline in aging perennial grass is not fully explained by leaf nitrogen, Journal of Experimental Botany, Volume 73, Issue 22, 8 December 2022, Pages 7582–7595, https://doi.org/10.1093/jxb/erac382. Posted with permission.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.