Aj. Devilliers et al., SALINITY-INDUCED CHANGES IN ANATOMY, STOMATAL COUNTS AND PHOTOSYNTHETIC RATE OF ATRIPLEX SEMIBACCATA R BR, South African journal of botany, 62(5), 1996, pp. 270-276
Anatomical changes in the roots and leaves of Atriplex semibaccata R.
Br., induced by salinity stress, as well as photosynthetic and stomata
l response to salinity, were investigated. As salinity increased, decr
eases were observed in root diameter and leaf size, as well as in the
number of chloroplasts in the chlorenchyma and bundle sheath cells. De
velopment of these two cell types was also inhibited. Net leaf photosy
nthetic rate and leaf stomatal conductance decreased with increasing s
alinity, while the intercellular CO2 concentration increased. Both sto
matal closure and inhibition of biochemical processes probably caused
the reduced leaf photosynthetic rates. The stomatal indices suggest th
at the trend towards an increase in number of stomata per unit leaf ar
ea with an increase in salinity was not due to decreased epidermal cel
l size.