Morphological and biochemical response of eight pomegranate (Punica granatum L.) cultivars under salinity stress

Identification of pomegranate cultivars with higher tolerance to salinity stress was the purpose of current study.

One-year-old rooted cuttings of the pomegranate cultivars including 'Malase Saveh' ('M-Saveh'), 'Malase Isfahan' ('M-Isfahan'), 'Robabe Ghermeze Shiraz' ('Robab'), 'Gabrie Yazd' ('G-Yazd'), Gabrie Torshe Yazd' ('GT-Yazd'), 'Zaghe Sefide Yazd' ('ZS-Yazd'), 'Zaghe Torshe Yazd' ('ZT-Yazd') and 'Malase Torshe Pishva' ('M-Pishva') were cultured in plastic pots and treated with different concentrations of sodium chloride in irrigation water including: 0 (control), 3, 6, 9 and 12 dS m-1.

At 12 dS m-1salinity level, the lowest decrease in plant height was observed in 'Robab' and 'M-Pishva' and the lowest decrease in the plant diameter was recorded in 'ZT-Yazd' and 'G-Yazd'. At the same salinity level, 'GT-Yazd' showed the lowest percentage of increase in electrolyte leakage (EL) compared to the control (23 %). The highest increase in proline content was observed at 9 dS m-1 salinity for 'ZS-Yazd' and at 12 dS m-1 salinity for 'GT-Yazd'. At high salinity levels, leaf chlorophyll content decreased in pomegranate cultivars compared to the control. The activity of peroxidase enzyme in 'M- Pishva', ZT-Yazd' and 'GT-Yazd' followed an increasing and then decreasing with increasing salinity levels. The activity of the superoxide dismutase enzyme was highest in 'G-Yazd', 'M-Isfahan' and 'Robab'.

 Limitations:

 Investigation of salinity tolerance in pots is one of the limitations of this study.

Originality/Value:

Yazd cultivars including 'G-Yazd', 'GT-Yazd', 'ZS-Yazd' and 'ZT-Yazd' were more tolerant to salinity stress.