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Excitation distribution to photosystem II

Range	0.42 to 0.6 Unitless
Organism	Various
Reference	Laisk A, Loreto F. Determining Photosynthetic Parameters from Leaf CO2 Exchange and Chlorophyll Fluorescence (Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Specificity Factor, Dark Respiration in the Light, Excitation Distribution between Photosystems, Alternative Electron Transport Rate, and Mesophyll Diffusion Resistance. Plant Physiol. 1996 Mar110(3):903-912. p.907 table 1 2nd column from left and p.910 left column 2nd paragraphPubMed ID12226229
Method	Excitation of photosystem II (YIIm) was determined from the relationship between photosynthesis and Chlorophyll fluorescence when photorespiration was suppressed by decreasing O2 concentration to 1.5%.
Comments	The lower YIIm values were obtained from leaves exposed to high light in their natural habitats. In tree leaves, YIIm was higher, probably because these leaves were collected from partially shaded sites. The parameter YIIm is the excitation distribution factor to PSII.
Entered by	Uri M
ID	106051