Impact of NaCl on leaf abscission, ion content and photosynthetic indices of seven commercial Fig (Ficus carica.L) cultivars

The Fig (Ficus carica.L) is a woody perennial crop, cultivated worldwide in subtropical regions. Since, salinity is the main concern of fig industry, therefore, studying the pattern of ion absorption and accumulation contribute during the stress in different plant organs can lead understanding the mechanism of tolerance/sensitivity. So, during ۲۰۱۶-۲۰۱۷, seven fig cultivars (‘Sabzʼ, ‘Siyahʼ, ‘Shah Anjirʼ, ‘Atabakiʼ, ‘Kashkiʼ, ‘Matiʼ and ‘Barʼ) were subjected to saline water (۰.۵, ۲, ۴, ۶, ۸ and ۱۰ dSm-۱). Then, ions accumulation of different organs, leaf abscission, dry matter, relative water content, and photosynthetic indices were compared to introduce the most salt-tolerant cultivar. The results indicated salinity caused a decrease in leaf relative water content, photosynthesis rate, K content and an increase in leaf abscission, Cl and Na content. Principal component analysis of the data led to a reduction in the variables with major contributions from the content of K, Na and Na/K of leaf and root, shoot Na, leaf Cl, and RWC. The ‘Siyahʼ and ‘Sabzʼ, as the most salt-tolerant cultivars, had the maximum leaf abscission, the least Na content and the maximum shoot dry matter under salt condition. The ‘Shah Anjirʼ, as the most salt-sensitive cultivar, could not restrict root Cl ex-flux into shoot and leaf.

Keywords:

Dry matter , Intercellular CO۲ concentration , Ion contents , Leaf abscission , Photosynthetic rate , Relative water content