METHOD FOR ASSESSMENT OF HO AND CO PARAMETERS OF GAS EXCHANGE OF PLANT LEAVES Russian patent published in 1994 - IPC

FIELD: experimental plane physiology. SUBSTANCE: leaf with stomata in its upper and lower parts is inserted in a leaf chamber to divide the latter into the upper and lower isolated parts. A gas metering unit is used in taking stationary mode measurements of rates of CO₂ transpiration and assimilation by the lower and upper leaf sides with controllable concentrations of H₂O-steam and CO₂ in air over both sides of the leaf. Then measurements of concentrations of H₂O-steam and CO₂ are taken above one side of the leaf, and the resulting change in total rates of CO₂ transpiration and assimilation is compensated for by increasing or decreasing the concentrations of respectively H₂O-steam and CO₂ in air above the other side of the leaf. Second rates of transpiration and assimilation of CO₂ for the upper and lower sides are measured as well as respective concentrations of H₂O-steam and CO₂ in air over both sides, and the kinetic parameters wanted are derived from equations given in the description. EFFECT: more accurate method.