Wang Xiao-Qian, Zeng Zhi-Lan, Shi Zi-Ming, Wang Ji-Hua, Huang Wei
School of Life Sciences, Northwest University, Xi'an 710069, China.
Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
Plants (Basel). 2023 Mar 6;12(5):1186. doi: 10.3390/plants12051186.
Photosynthetic efficiency under both steady-state and fluctuating light can significantly affect plant growth under naturally fluctuating light conditions. However, the difference in photosynthetic performance between different rose genotypes is little known. This study compared the photosynthetic performance under steady-state and fluctuating light in two modern rose cultivars (), "Orange Reeva" and "Gelato", and an old Chinese rose plant cultivar, "Slater's crimson China". The light and CO response curves indicated that they showed similar photosynthetic capacity under steady state. The light-saturated steady-state photosynthesis in these three rose genotypes was mainly limited by biochemistry (60%) rather than diffusional conductance. Under fluctuating light conditions (alternated between 100 and 1500 μmol photons m m every 5 min), stomatal conductance gradually decreased in these three rose genotypes, while mesophyll conductance () was maintained stable in Orange Reeva and Gelato but decreased by 23% in , resulting in a stronger loss of CO assimilation under high-light phases in (25%) than in Orange Reeva and Gelato (13%). As a result, the variation in photosynthetic efficiency under fluctuating light among rose cultivars was tightly related to . These results highlight the importance of in dynamic photosynthesis and provide new traits for improving photosynthetic efficiency in rose cultivars.
在稳态光和波动光条件下的光合效率会显著影响自然波动光条件下的植物生长。然而，不同玫瑰基因型之间光合性能的差异却鲜为人知。本研究比较了两个现代玫瑰品种“橙色瑞瓦”和“吉拉多”以及一个古老的中国玫瑰品种“斯莱特深红中国”在稳态光和波动光下的光合性能。光响应曲线和二氧化碳响应曲线表明，它们在稳态下表现出相似的光合能力。这三种玫瑰基因型的光饱和稳态光合作用主要受生化因素限制（60%），而非扩散传导。在波动光条件下（每5分钟在100和1500 μmol光子·m⁻²·s⁻¹之间交替），这三种玫瑰基因型的气孔导度逐渐降低，而橙色瑞瓦和吉拉多的叶肉导度保持稳定，但斯莱特深红中国的叶肉导度下降了23%，导致其在高光阶段的二氧化碳同化损失（25%）比橙色瑞瓦和吉拉多（13%）更大。因此，玫瑰品种间波动光下光合效率的差异与叶肉导度密切相关。这些结果突出了叶肉导度在动态光合作用中的重要性，并为提高玫瑰品种的光合效率提供了新的性状。
