Sanhueza Carolina, Cortes Daniela, Way Danielle A, Fuentes Francisca, Bascunan-Godoy Luisa, Fernandez Del-Saz Nestor, Sáez Patricia L, Bravo León A, Cavieres Lohengrin A
Laboratorio de Fisiología Vegetal, Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Barrio Universitario s/n, Concepción, Casilla 160-C, Concepción 4030000, Chile.
Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile.
Plants (Basel). 2022 Jun 6;11(11):1520. doi: 10.3390/plants11111520.
Projected rises in atmospheric CO concentration and minimum night-time temperatures may have important effects on plant carbon metabolism altering the carbon balance of the only two vascular plant species in the Antarctic Peninsula. We assessed the effect of nocturnal warming (8/5 °C vs. 8/8 °C day/night) and CO concentrations (400 ppm and 750 ppm) on gas exchange, non-structural carbohydrates, two respiratory-related enzymes, and mitochondrial size and number in two species of vascular plants. In , light-saturated photosynthesis measured at 400 ppm was reduced when plants were grown in the elevated CO or in the nocturnal warming treatments. Growth in elevated CO reduced stomatal conductance but nocturnal warming did not. The short-term sensitivity of respiration, relative protein abundance, and mitochondrial traits were not responsive to either treatment in this species. Moreover, some acclimation to nocturnal warming at ambient CO was observed. Altogether, these responses in led to an increase in the respiration-assimilation ratio in plants grown in elevated CO. The response of to the experimental treatments was quite distinct. Photosynthesis was not affected by either treatment; however, respiration acclimated to temperature in the elevated CO treatment. The observed short-term changes in thermal sensitivity indicate type I acclimation of respiration. Growth in elevated CO and nocturnal warming resulted in a reduction in mitochondrial numbers and an increase in mitochondrial size in . Overall, our results suggest that with climate change could be more successful than , due to its ability to make metabolic adjustments to maintain its carbon balance.
大气中二氧化碳浓度的预计上升以及夜间最低温度的升高，可能会对植物碳代谢产生重要影响，从而改变南极半岛仅有的两种维管植物的碳平衡。我们评估了夜间升温（日/夜温度为8/5°C 与 8/8°C）和二氧化碳浓度（400 ppm 和 750 ppm）对两种维管植物的气体交换、非结构性碳水化合物、两种与呼吸相关的酶以及线粒体大小和数量的影响。在[具体植物名称1]中，当植物在高二氧化碳浓度或夜间升温处理条件下生长时，在400 ppm 下测得的光饱和光合作用降低。高二氧化碳浓度下的生长降低了气孔导度，但夜间升温没有。该物种中呼吸作用、相对蛋白质丰度和线粒体特征的短期敏感性对这两种处理均无反应。此外，在环境二氧化碳浓度下观察到了对夜间升温的一些适应性变化。总体而言，[具体植物名称1]中的这些反应导致高二氧化碳浓度下生长的植物呼吸-同化比增加。[具体植物名称2]对实验处理的反应截然不同。光合作用不受任何一种处理的影响；然而，在高二氧化碳浓度处理中，呼吸作用适应了温度。观察到的热敏感性短期变化表明呼吸作用存在I型适应性变化。高二氧化碳浓度下的生长和夜间升温导致[具体植物名称2]中线粒体数量减少和线粒体大小增加。总体而言，我们的结果表明，随着气候变化，[具体植物名称1]可能比[具体植物名称2]更成功，因为它有能力进行代谢调整以维持其碳平衡。
