Gong Xiao-Ying, Ma Wei-Ting, Yu Yong-Zhi, Li Lei
College of Geographical Sciences, Fujian Normal University/Breeding Base of Key Laboratory for Subtropical Mountain Ecology, Fuzhou 350007, China.
Ying Yong Sheng Tai Xue Bao. 2020 Jun;31(6):1882-1888. doi: 10.13287/j.1001-9332.202006.010.
Mesophyll conductance (g), the total conductance of CO diffusion from substomatal cavity to the site of carboxylation within chloroplast, is a major limiting factor for photosynthesis and a key parameter for improving photosynthetic resource use efficiency of crops. Online C discrimination method is an important method for plant eco-physiological studies and a well-established method for measuring g of C3 plants, although it has not been widely used due to challenges in methodology and high demands on experimental facilities. In this review, we summarized the characteristics of commonly used methods for g, introduced the basic theory of the online C discrimination method, namely Farquhar's photosynthetic C discrimination model; systematically introduced the practical measurements, equations and the components of facilities; and reviewed the drivers for variation in g of C3 plants. At the last part, we discussed the outlook of the development of methodology, new experimental protocols, and applications in measurement scenarios.
叶肉导度（g）是二氧化碳从气孔下腔扩散到叶绿体羧化部位的总导度，是光合作用的主要限制因素，也是提高作物光合资源利用效率的关键参数。在线碳同位素分馏法是植物生态生理研究的重要方法，也是测量C3植物g值的成熟方法，尽管由于方法学上的挑战和对实验设施的高要求，该方法尚未得到广泛应用。在这篇综述中，我们总结了常用g值测量方法的特点，介绍了在线碳同位素分馏法的基本理论，即法夸尔光合碳同位素分馏模型；系统地介绍了实际测量、公式和设施组成；并综述了C3植物g值变化的驱动因素。在最后一部分，我们讨论了该方法的发展前景、新的实验方案以及在测量场景中的应用。
