Environmental factors have a greater influence on photosynthetic capacity in C 4 plants than biochemical subtypes or growth forms

作者：Yuzhen Fan, Daniel W. A. Noble, Belinda E. Medlyn, Russell K. Monson, Rowan F. Sage, Nicholas G. Smith, Elizabeth A. Ainsworth, Florian A. Busch, Florence R. Danila, Maria Ermakova, Patrick Calvin Friesen, Robert T. Furbank, Shu Han Gan, Oula Ghannoum, Daniel M. Griffith, Lianhong Gu, Vinod Jacob, Jürgen Knauer, Andrew D. B. Leakey, Shuai Li, Danica Lombardozzi, Martha Ludwig, Varsha S. Pathare, Murilo de Melo Peixoto, Karine Prado, Balasaheb V. Sonawane, Christopher J. Still, Susanne von Caemmerer, Russell Woodford, Danielle A. Way · 发表于：New Phytologist · 年份：2025 · DOI：10.1111/nph.70525 · 被引用次数：4 · 研究领域：Atmospheric and Environmental Gas Dynamics、Plant Water Relations and Carbon Dynamics、Photosynthetic Processes and Mechanisms

Summary Our understanding of how photosynthetic capacity varies among C 4 species and across growth and measurement conditions remains limited. We collated 1696 CO 2 response curves of net CO 2 assimilation rate ( A / C i curves) from C 4 species grown and measured at various environmental conditions and used these data to estimate the apparent maximum carboxylation activity of phosphoenolpyruvate carboxylase ( V pmaxA ) and CO 2 ‐saturated net photosynthetic rate ( A max ), two key parameters describing photosynthetic capacity. We examined how V pmaxA and A max vary with species‐specific traits, growth and measurement conditions. We found little systematic variation of V pmaxA and A max across the classical C 4 biochemical subtypes or growth forms, but showed that growth temperature and measurement conditions are major factors determining C 4 photosynthetic capacity. We found no evidence that common C 4 model species (e.g. maize, sorghum and Setaria viridis ) differ in photosynthetic capacity from other C 4 species when grown in controlled environments. However, C 4 model species showed up to twice the photosynthetic capacity of other C 4 species when grown in the field. Our multivariate model accounts for 47–51% of the variation reported in V pmaxA and A max , and we argue that environmental conditions have a greater influence on C 4 photosynthetic capacity than biochemical subtypes or growth forms.