Details

Autor(en) / Beteiligte

• Han, Jimei
• Gu, Lianhong
• Wen, Jiaming
• Sun, Ying

Titel

Inference of photosynthetic capacity parameters from chlorophyll a fluorescence is affected by redox state of PSII reaction centers

Ist Teil von

• Plant, cell and environment, 2022-04, Vol.45 (4), p.1298-1314

Ort / Verlag

United States: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Solar‐induced chlorophyll fluorescence (SIF) has been used to infer photosynthetic capacity parameters (e.g., the maximum carboxylation rate Vcmax, and the maximum electron transport rate Jmax). However, the precise mechanism and practical utility of such approach under dynamic environments remain unclear. We used the balance between the light and carbon reactions to derive theoretical equations relating chlorophyll a fluorescence (ChlF) emission and photosynthetic capacity parameters, and formulated testable hypotheses regarding the dynamic relationships between the true total ChlF emitted from PSII (SIFPSII) and Vcmax and Jmax. We employed concurrent measurements of gas exchanges and ChlF parameters for 15 species from six biomes to test the formulated hypotheses across species, temperatures, and limitation state of carboxylation. Our results revealed that SIFPSII alone is incapable of informing the variations in Vcmax and Jmax across species, even when SIFPSII is determined under the same environmental conditions. In contrast, the product of SIFPSII and the fraction of open PSII reactions qL, which indicates the redox state of PSII, is a strong predictor of both Vcmax and Jmax, although their precise relationships vary somewhat with environmental conditions. Our findings suggest the redox state of PSII strongly influences the relationship between SIFPSII and Vcmax and Jmax. Summary statement Our theoretical and measurement results revealed that the fraction of open PSII reaction centers qL, which indicates the redox state of PSII plays an important role when chlorophyll afluorescence is used to infer Vcmax25 and Jmax25. The limitation state of carboxylation must be considered if observed chlorophylla fluorescenceis utilized to infer Vcmax25 (or Jmax25) under dynamic environmental conditions.