Main content area

Lisianthus response to salinity stress

Ashrafi, N., Rezaei Nejad, A.
Photosynthetica 2018 v.56 no.2 pp. 487-494
calcium, cultivars, electrolytes, gas exchange, leaf area, leaves, lipid peroxidation, malondialdehyde, photosynthesis, pigments, potassium, regression analysis, roots, salinity, salt stress, salt tolerance, sand, seedlings, shoots, sodium chloride, stomatal conductance, water content
The effect of salinity on some morpho-physiological characteristics in lisianthus cultivars was investigated. Cultivars namely, Blue Picotee (C1), Champagne (C₂), Lime Green (C₃), and Pure White (C₄), were subjected to salt stress (0–60 mM NaCl) in a sand culture and their responses were measured. Our results showed that as a salinity level increased, growth parameters, relative water content, photosynthetic pigments, and gas-exchange characteristics decreased in all cultivars, while root fresh mass, root/shoot length ratio, electrolyte leakage, and a malondialdehyde content increased. However, the changes were less pronounced in C₃ and C₄ compared to C1 and C₂. The regression analysis of the relationship between salinity levels and seedling height or root/shoot length ratio defined two groups with different slope coefficients: C1 and C₂ as salt-sensitive cultivars and C₃ and C₄ as salt-tolerant cultivars. Shoot dry mass and leaf area tolerance indices were less affected by salinity in C₃ and C₄ compared to those in C1 and C₂. Further, C₃ and C₄ showed higher photosynthetic rates, greater stomatal conductances, and accumulated greater K+ and Ca2+ contents and K+/Na+ ratios in roots and shoots compared to those in C1 and C₂. The results suggests that C₃ and C₄ could be recommended as resistant cultivars due to maintaining higher growth, water balance, leaf gas exchange, ion compartmentalization, and lower lipid peroxidation in response to salinity compared to C1 and C₂.