Interclonal variation, coordination, and trade-offs between hydraulic conductance and gas exchange in Pinus radiata : consequences on plant growth and wood density
Langue
EN
Article de revue
Ce document a été publié dans
Journal of Experimental Botany. 2021-03-29, vol. 72, n° 7, p. 2419-2433
Résumé en anglais
Abstract Stem growth reflects genetic and phenotypic differences within a tree species. The plant hydraulic system regulates the carbon economy, and therefore variations in growth and wood density. A whole-organism ...Lire la suite >
Abstract Stem growth reflects genetic and phenotypic differences within a tree species. The plant hydraulic system regulates the carbon economy, and therefore variations in growth and wood density. A whole-organism perspective, by partitioning the hydraulic system, is crucial for understanding the physical and physiological processes that coordinately mediate plant growth. The aim of this study was to determine whether the relationships and trade-offs between (i) hydraulic traits and their relative contribution to the whole-plant hydraulic system, (ii) plant water transport, (iii) CO2 assimilation, (iv) plant growth, and (v) wood density are revealed at the interclonal level within a variable population of 10 Pinus radiata (D. Don) clones for these characters. We demonstrated a strong coordination between several plant organs regarding their hydraulic efficiency. Hydraulic efficiency, gas exchange, and plant growth were intimately linked. Small reductions in stem wood density were related to a large increase in sapwood hydraulic efficiency, and thus to plant growth. However, stem growth rate was negatively related to wood density. We discuss insights explaining the relationships and trade-offs of the plant traits examined in this study. These insights provide a better understanding of the existing coordination, likely to be dependent on genetics, between the biophysical structure of wood, plant growth, hydraulic partitioning, and physiological plant functions in P. radiata.< Réduire
Mots clés en anglais
Carbon allocation
hydraulic architecture
hydraulic partitioning
photosynthesis
Pinus radiata
plant growth
wood density
Unités de recherche