Abstract:
This study aimed to detect possible strategies used by olive (
O
lea
europaea
L.
) a
nd
pistachio (
Pistacia vera
L.
) species under saline conditions to be considered in early
selection programs of salt
-
tolerant genotypes. One
-
year
-
old seedlings were irrigated
alternatively with ½ Hoagland nutrient solution and distilled water added with 0,
75, or
150 mM NaCl during 3 months under controlled conditions. Growth, leaf toxicity
symptoms, and shoot and root mineral compositions were assessed. Salt induced leaf
injury and a significant decrease in growth of both species seedlings. The decrease in
shoot elongation was more pronounced on pistachio seedlings, whereas leaf formation and
plant fresh weight showed greater reduction on olive plants. Pistachio seedlings developed
new axillary shoots and leaves at 75 mM NaCl. The root fresh weight was sign
ificantly
reduced by salinity in olive, but remained unaffected in pistachio. Both saline treatments
induced leaf fall with more pronounced effect on
olive plants
. Olive salt tolerance may be
associated to a better control of Na
+
accumulation in the leaves
and its ability to
accumulate potassium in shoots in order to achieve osmotic adjustment. Pistachio
seedlings seemed to better control Cl
–
ion ascension from roots to shoots through salt ion
dilution mechanism. The increase in root fresh weight of pistach
io seedlings at both salt
treatments and the higher ability of this species for uptake of calcium (involved in the
regulation of stomata movement) seem to support this hypothesis.
Keywords
:
Olea europaea
L.,
Pistacia vera
L., Sodium chloride, Toxicity sym
ptoms, Water
salinity.
