Effects of elevated [CO2] on gas exchange parameters in the last fully-expanded leaves of I. indigotica.

Measurement was taken on their respective [CO2]. Values are means ± standard error of variables across the three replicates; three plants were tested in each plot. The statistical significance level for the effects of [CO2] treatment, growth stage and their interaction was tested. PN - net photosynthetic rate; gs- stomatal conductance; Tr - transpiration ratio; WUE- water use efficiency; Vc,max- maximum velocity of carboxylation; Jmax - maximum rate of electron transport.