Temperature acclimation of net photosynthesis and its underlying component processes in four tropical tree species

作者：Maria Wittemann, Mats X. Andersson, Bonaventure Ntirugulirwa, Lasse Tarvainen, Göran Wallin, Johan Uddling · 发表于：Tree Physiology · 年份：2022 · DOI：10.1093/treephys/tpac002 · 被引用次数：34 · 研究领域：Plant Water Relations and Carbon Dynamics、Plant responses to elevated CO2、Plant and animal studies

The effect of temperature change on leaf physiology has been extensively studied in temperate trees and to some extent in boreal and tropical tree species. While increased temperature typically stimulates leaf CO2 assimilation and tree growth in high-altitude ecosystems, tropical species are often negatively affected. These trees may operate close to their temperature optima and have a limited thermal acclimation capacity due to low seasonal and historical variation in temperature. To test this hypothesis, we studied the extent to which the temperature sensitivities of leaf photosynthesis and respiration acclimate to growth temperature in four common African tropical tree species. Tree seedlings native to different altitudes and therefore adapted to different growth temperatures were cultivated at three different temperatures in climate-controlled chambers. We estimated the acclimation capacity of the temperature sensitivities of light-saturated net photosynthesis, the maximum rates of Rubisco carboxylation (Vcmax) and thylakoid electron transport (J), and dark respiration. Leaf thylakoid membrane lipid composition, nitrogen content and leaf mass per area were also analyzed. Our results showed that photosynthesis in tropical tree species acclimated to higher growth temperatures, but that this was weakest in the species originating from the coolest climate. The temperature optimum of J acclimated significantly in three species and variation in J was linked to changes in the th...