文献类型： 外文期刊

作者： Ye, Zi-Piao ¹ ; Ling, Yu ² ; Yu, Qiang ³ ; Duan, Hong-Lang ⁶ ; Kang, Hua-Jing ⁷ ; Huang, Guo-Min ⁶ ; Duan, Shi-Hua ⁸ ; Ch ¹ ;

作者机构： 1.Jinggangshan Univ, Maths & Phys Coll, Jian, Jiangxi, Peoples R China

2.Guangdong Ocean Univ, Coll Agr Sci, Zhanjiang, Peoples R China

3.Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling, Shaanxi, Peoples R China

4.Univ Technol Sydney, Sch Life Sci, Ultimo, NSW, Australia

5.Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China

6.Nanchang Inst Technol, Jiangxi Prov Key Lab Restorat Degraded Ecosyst &, Nanchang, Jiangxi, Peoples R China

7.Wenzhou Vocat Coll Sci & Technol, Dept Landscape Architecture, Wenzhou, Peoples R China

8.Jinggangshan Univ, Sch Life Sci, Jian, Jiangxi, Peoples R China

9.Jiangxi Acad Agr Sci, Soil Fertilizer & Environm Resources Inst, Nanchang, Jiangxi, Peoples R China

10.Chinese Acad Forestry, Inst Desertificat Studies, Beijing, Peoples R China

11.New Zealand Inst Plant & Food Res Ltd, Havelock North, New Zealand

关键词： irradiance; leaf gas exchange; light response curve; maximum water use efficiency; model; plant functional type (PFT); saturation light intensity; transpiration

期刊名称：FRONTIERS IN PLANT SCIENCE （ 影响因子：5.753； 五年影响因子：6.612 ）

ISSN： 1664-462X

年卷期： 2020 年 11 卷

页码：

收录情况： SCI

摘要： Light intensity (I) is the most dynamic and significant environmental variable affecting photosynthesis (A(n)), stomatal conductance (g(s)), transpiration (T-r), and water-use efficiency (WUE). Currently, studies characterizing leaf-scale WUE-I responses are rare and key questions have not been answered. In particular, (1) What shape does the response function take? (2) Are there maximum intrinsic (WUEi; WUEi max) and instantaneous WUE (WUEinst; WUEinst-max) at the corresponding saturation irradiances (Ii-sat and Iinst-sat)? This study developed WUEi-I and WUEinst-I models sharing the same non-asymptotic function with previously published A(n-I) and g(s-I) models. Observation-modeling intercomparison was conducted for field-grown plants of soybean (C-3) and grain amaranth (C-4) to assess the robustness of our models versus the non-rectangular hyperbola models (NH models). Both types of models can reproduce WUE-I curves well over light-limited range. However, at light-saturated range, NH models overestimated WUEi-max and WUEinst-max and cannot return Ii-sat and Iinst-sat due to its asymptotic function. Moreover, NH models cannot describe the down-regulation of WUE induced by high light, on which our models described well. The results showed that WUEi and WUEinst increased rapidly within low range of I, driven by uncoupled photosynthesis and stomatal responsiveness. Initial response rapidity of WUEi was higher than WUEinst because the greatest increase of A(n) and T-r occurred at low gs. C4 species showed higher WUEi-max and WUEinst-max than C-3 species-at similar Ii sat and Iinst sat. Our intercomparison highlighted larger discrepancy between WUEi-I and WUEinst-I responses in C-3 than C-4 species, quantitatively characterizing an important advantage of C-4 photosynthetic pathway-higher A(n) gain but lower T-r cost per unit of g(s) change. Our models can accurately return the wealth of key quantities defining species-specific WUE-I responses-besides A(n-I) and g(s-I) responses. The key advantage is its robustness in characterizing these entangled responses over a wide I range from light-limited to light-inhibitory light intensities, through adopting the same analytical framework and the explicit and consistent definitions on these responses. Our models are of significance for physiologists and modelers-and also for breeders screening for genotypes concurrently achieving maximized photosynthesis and optimized WUE.