Plant Water Status, Leaf Temperature, and the Calculated Mesophyll Resistance to Carbon Dioxide of Cotton Leaves

Abstract

The influence of plant water status and leaf temperature on the mesophyll resistance to C02 transfer for Deltapine cotton leaves was determined under condi-tions when the C02 supply was limiting photosynthesis. The mesophyll resistance was calculated from C02 response curves in normal air and oxygen-free air, under conditions when air was forced from the abaxial to adaxial side of the leaf to obtain a direct estimate of the CO2 concentration at the mesophyll cell wall.