| Summary: | Salinity is one of the major abiotic stresses of crops, since it affects more than onethird of irrigated land in the world, limiting agricultural production. Salinity causes
imbalances in ion homeostasis with increases in Cl- and Na+ concentration, and
even in moderate concentrations may cause significant physiological changes in
plants, such as reduction of growth and development, necrosis of leaves and
shoots, defoliation, etc. Then, exposure to salt stunts plant growth and significantly
reduces yield. We studied responses of Actinidia deliciosa (Chev) Liang and Ferguson cv Tomuri and cv Hayward, with two different salinity concentrations (0 and
40 mM NaCl), for 60 days, with six replicates per treatment and cultivar. Growth,
ion content and gas exchange response to salt treatment were examined at the end
of the experiment. Salinity impaired plant growth, with decreases in leaves, stem
and roots of all the treated plants. All cultivars increased Cl and Na content in
leaves and roots, but Tomuri accumulated less Cl and Na concentration in roots
than Hayward. Leaf gas exchange parameters in salt treated plants were reduced
to different extents, depending on the cultivar. The decreases in net CO2 assimilation were more pronounced in Tomuri, but both cultivar showed similar decreases
in transpiration rate.
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