Experiments were carried out at EI-Bramoon Exper. Farm during 2001 and
2002 summer seasons, to study the effect of salinity stress (3000 and 6000 ppm
NaCI) and three ameliorative anti stress substances, i.e. citrate (5 gil citric acid).
phosphate (0.35 milL H3PO.) and nitrate (0.35 mVHNo,) ions In Irrigation water and
their Interaction to improve different performance of sweet pepper Baladi cv. Results
indicated that: Plant height. number of leaves and shoots, dry weight of shoots, roots and
the whole plant, shoot I root ratio, number of flowers and fruits, fnJit yield and Quality
(on plant basis) were significantly reduced In two seasons by increasing salinity. Total
dry weight decreased by 26.8 and 38.3%, fruit yield decreased by 12.2 and 29.2%
(means of two seasons relative to control) at 3000 and 6000 ppm NaCl, respectively.
Also, along with salinity, Na and CI were excessively accumulated vs. low N, P and K
content within leaves and roots, Na and CI in leaves increased by (100 and 129.3%),
(192.8 and 292.8%), whereas K decreased by 18.5 and 38.3% at 3000 and 6000 ppm
NaCI, respectively relative to control. KINa value significantly decreased, EC,lEC2
and NallNar were increased (impairment of membrane), Increased permeability and
electrolyte leakage and higher Na selectivity case). Concerning effect of the ameliorative ions, Citrate> phosphate> nitrate were
greatly improved all the mentioned characterfstics. they increased total dry weight of
planl'by 41.2. 36.0 and 28.0%, fruit yield I plant by 56.8, 43.0 and 35.7%. respectively
relative to control. As for interaction effect. presence of the ameliorative ions in the same trend
were highly improved growth, ionic. mineral and prysiological per10rmances and fully
restored fruit yield to the normal case of non-stressed plants at 3000 ppm NaCI and to
some extent at 6000 ppm NaCI. Some important indicators for salinity adaptation case were P and K content
(positively correlated with fruit yield), CI content and EC,lEC₂ value (negatively
correlated with fruit yield). It could be concluded that adding citric acid 5 gmlL (citric ion) and/or
pbosphoric acid (0.35 mill) in irrigation water 3 times during the season. to obtain the
best growth and productivity of sweet pepper during similar stress conditions. Also.
that Baladi sweet pepper considered as less to moderately salt sensitive plant at
moderate to higher salinities.