Differences in leaf anatomy determines temperature response of leaf hydraulic and mesophyll CO2 conductance in phylogenetically related C4 and C3 grass species. Issue 5 (25th March 2021)

• Record Type: Journal Article
• Authors: Sonawane, Balasaheb V.; Koteyeva, Nuria K.; Johnson, Daniel M.; Cousins, Asaph B.
• Is Part Of: New phytologist. Volume 230:Issue 5(2021)
• Page Start: 1802
• Page End: 1814
• Publication Date: 2021-03-25
• Subjects: C4 and C3 photosynthesis -- leaf hydraulic conductance -- leaf hydraulic conductance inside xylem -- leaf hydraulic conductance outside xylem -- mesophyll conductance to CO2 -- temperature response; Botany -- Periodicals; 580
• DOI: 10.1111/nph.17287
• Languages: English
• ISSNs: 0028-646X

Abstract

Summary: Leaf hydraulic and mesophyll CO2 conductance are both influenced by leaf anatomical traits, however it is poorly understood how the temperature response of these conductances differs between C4 and C3 species with distinct leaf anatomy. This study investigated the temperature response of leaf hydraulic conductance ( K leaf ), stomatal ( g s ) and mesophyll ( g m ) conductance to CO2, and leaf anatomical traits in phylogenetically related Panicum antidotale (C4 ) and P. bisulcatum (C3 ) grasses. The C4 species had lower hydraulic conductance outside xylem ( K ox ) and K leaf compared with the C3 species. However, the C4 species had higher g m compared with the C3 species. Traits associated with leaf water movement, K leaf and K ox, increased with temperature more in the C3 than in the C4 species, whereas traits related to carbon uptake, A net and g m, increased more with temperature in the C4 than the C3 species. Our findings demonstrate that, in addition to a CO2 concentrating mechanism, outside‐xylem leaf anatomy in the C4 species P . antidotale favours lower water movement through the leaf and stomata that provides an additional advantage for greater leaf carbon uptake relative to water loss with increasing leaf temperature than in the C3 species P. bisulcatum .