2.2. Short-term experiment (10 days of salt stress)
Fifteen days after grafting, the plants were transferred into
20 L plastic containers (eight plants per container) containing fullstrength
Hoagland solution (Hoagland and Arnon, 1950). At the
three-leaf stage, the plants were treated with either 1 mM (tap
water containing 1 mM NaCl) or 91 mM NaCl for 10 days. The EC
of the nutrient solutions was 2.05 dS m−1 and 9.87 dS m−1, respectively.
The twelve treatments (six combinations of plants × two
salt concentrations) were replicated three times, with eight
plants in each replicate, and arranged in a randomized complete
block design. During the greenhouse culture, the plants
were grown at day maximal photosynthetic photon flux density
(PPFD) 1051 mol m−2 s−1 (average PPFD 289 mol m−2 s−1),
day temperature between 17 ◦C and 36 ◦C (average temperature
26 ◦C), night temperature not lower than 14 ◦C, and day relative
h