Wy. Kao et al., Effect of NaCl and nitrogen availability on growth and photosynthesis of seedlings of a mangrove species, Kandelia candel (L.) Druce, J PLANT PHY, 158(7), 2001, pp. 841-846
The growth, photosynthetic gas exchange, leaf stable carbon isotope ratio (
delta C-13), osmotic potential (psi (s)), and sodium (Na) and potassium (K)
contents were measured in seedlings of a mangrove species, Kandelia candel
(L.) Druce, grown under combinations of two kinds of nitrogen availability,
high and low nitrogen (0.1 and 0.01 mmol/L NH4NO3), and three NaCl treatme
nts, low, medium, and high salinity (85, 250, and 430 mmol/L NaCl). The obj
ectives of this study were to investigate the responses of these parameters
to salinity during growth and to evaluate whether nitrogen availability al
ters these responses. The accumulation of biomass, shoot elongation, photos
ynthetic rate, stomata conductance, leaf psi (s), and leaf K contents were
found to decrease with increasing NaCl. In contrast, leaf delta C-13 value
and Na content increase with increasing NaCl. An increase in N availability
significantly increased photosynthetic rates and leaf biomass, but lowered
root and leaf psi (s) of seedlings, in contrast, the amount of Na and K ac
cumulation in roots and leaves was not affected by nitrogen availability.