Abstract

To study the response of Iranian melon cultivars to salinity stress a factorial experiment based on RCBD with 3 replications was conducted. Four salinity treatments (0, 6.6, 8 and 12 dS/m NaCl) and 16 muskmelon (Cucumis melo L.) cultivars namely ‘Dargazi’, ‘Khatooni’, Abbas shori’, ‘Chah paliz’, ‘Zard Ivanaki’, ‘Gorgab’, ‘Gongi’, Saderati’, ‘Dastgerd’, ‘Sabz Isfahan’, ‘Jalali’, Ghasri Mashhad’, Sooski’, ‘Khaghani’, with two imported hybrids ‘Annanasi’ and ‘Diamond’ were used. The results showed that along with increasing salinity levels to 6.6, 8, and 12ds/m, the highest increase in electrolyte leakage and Na+ concentration (45.35 and 64.48%, respectively) were observed in Gongi cultivar, compared with the control. The largest decrease in chlorophyll fluorescence was found to be 21.95% in Dargazi cultivar. Greenness index, K+ concentration of leaf, K+/N+, fresh weight of shoot and dry weight of root were decreased by 52.31, 49.74, 82.19, 75.45, 76%, respectively, in salt stressed Gongi plants. The greatest salt induced decreases in RWC (71.36%) and fresh weight of root (60.36%) were observed in Gongi and Zard ivanaki cultivars in comparison to the control plants. Cluster analysis divided the examined accessions to 3 groups. Sabz Isfahan, Ananasi, Sooski, and Diamond were recognized as salt-tolerant accessions which may contain tolerance genes which could be used to develop new modified cultivars with high salinity resistance. Dargazi, Zard ivanaki and Gongi were the most sensitive ones to the salinity stress.