title: A kinetic model structure for delayed fluorescence from plants.
abstract: In this research, we demonstrated that the plastoquinone-related electron-transport kinetics in photosynthesis could be sufficiently described with as few as three state variables, Q(A)(-), Q(B)(-), and Q(B)(2-). A third-order kinetic model structure was developed with delayed fluorescence as the measurable output. Delayed fluorescence emissions from drought-stressed, DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea] treated, or healthy plants were measured with a photon-counting system and used to verify the model structure through nonlinear least-squares optimization. While there were no visible differences between the healthy and the stressed plants, the model showed an obvious decrease of Q(A) reduction rate in the drought-stressed samples and a clear decline of functional Q(A)Q(B) pairs in the DCMU-treated samples. The changes were consistent with the known mechanisms by which water and DCMU affect electron transport in photosynthetic plants. The results proved that the three-state formulation was a compact and practically useful model structure for describing delayed fluorescence from plants.
authors.affiliation: Department of Biological Engineering, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Ya
authors.initials: Y
authors.lastname: Guo
authors.forename: Jinglu
authors.initials: J
authors.lastname: Tan
mesh_terms: D004237:Diuron / Q000378:metabolism*; D004579:Electron Transport / Q000502:physiology; D005453:Fluorescence; D007700:Kinetics; D008954:Models, Biological; D010084:Oxidation-Reduction; D027805:Phaseolus; D010788:Photosynthesis / Q000502:physiology*; D018521:Plant Physiological Phenomena; D013025:Glycine max; D013312:Stress, Physiological / Q000502:physiology*; D014867:Water / Q000378:metabolism; D003313:Zea mays
chemical_list: D014867:Water; D004237:Diuron