Relationship between the effects of salinity on seedling leaf area and fruit yield of six muskmelon cultivars

Six muskmelon (Cucumis melo L.) Galia-type cultivars ('Delada', 'Gallicum', 'Galor' 'Melina', 'Regal' and 'Revigal') were tested for salt tolerance at the seedling stage and during growth in the field. Three levels of salinity (EC(w) 2.5 (control), 5.0 and 7.5 dS·m-1), established by adding NaCl to fresh water, were used. The effect of salinity on seedling growth was assessed by measuring the total leaf area 36 days after sowing. 'Melina' was the most tolerant at this stage and during subsequent growth in field, with a relative seedling leaf area of 60 and a relative yield of 66 at 7.5 dS·m-1 salinity, both expressed as a percentage of the values obtained at the control level of salinity. 'Delada' was the most sensitive to the highest level of salinity at both stages, with relative seedling leaf area and yield of 51 and 56, respectively. For all cultivars, a highly significant correlation (r = 0.99) was established between the influence of salinity on seedling leaf area reduction and on decrease in yield during field culture. The results indicate that the reduction in seedling leaf area can be a good selection criterion to facilitate rapid screening for salt tolerance in muskmelon.