Salinity-induced changes in anatomy, stomatal counts and photosynthetic rate of Atriplex semibaccata R. Br.
In a pot experiment, A. semibaccata was exposed to 3 levels of saline stress. As salinity increased, decreases were observed in root diameter and leaf size, as well as in the number of chloroplasts in the chlorenchyma and bundle sheath cells. Development of these two cell types was also inhibited. Net leaf photosynthetic rate and leaf stomatal conductance decreased with increasing salinity, while the intercellular CO2 concentration increased. Both stomatal closure and inhibition of biochemical processes probably caused the reduced leaf photosynthetic rates. The stomatal indices suggested that the trend towards an increase in number of stomata per unit leaf area with an increase in salinity was not due to decreased epidermal cell size.