Relationship between 18O enrichment in leaf biomass and stomatal conductance.
Models that explain the oxygen isotope enrichment in leaf water (and biomass) treat the relationship between the kinetic fractionation that occurs during evapotranspiration and the stomatal conductance in an empirical way. Consequently, the isotopic enrichment is always predicted to decrease with increasing stomatal conductance, regardless of the experimental evidence to the contrary. We explain why and suggest an alternative method to reconcile theory and experiment. We support this with our experimental data on rice and groundnut plants.
Sheshshayee
Madavalam Sreeman
MS
Department of Crop Physiology, University of Agricultural Sciences, Bangalore, India. msheshshayee@hotmail.com
Bindumadhava
Hanumantha Rao
HR
Ramesh
Rengaswamy
R
Prasad
Trichy Ganesh
TG
Udayakumar
Makarla
M
D010367:Arachis / Q000235:genetics / Q000378:metabolism; D018533:Biomass; D007700:Kinetics; D008954:Models, Biological; D012275:Oryza / Q000235:genetics / Q000378:metabolism; D010100:Oxygen / Q000032:analysis / Q000378:metabolism*; D010103:Oxygen Isotopes; D018515:Plant Leaves / Q000378:metabolism*; D054046:Plant Stomata / Q000378:metabolism*; D018526:Plant Transpiration / Q000235:genetics / Q000502:physiology*
D010103:Oxygen Isotopes; D010100:Oxygen