A hydroponic experiment was conducted to assess whether grafting with Cucurbita rootstocks could improve the salt tolerance of melon scions and to determine the physiological, biochemical, and nutritional responses induced by the rootstocks under salt stress. Two melon (Cucumis melo L.) cultivars (Citirex and Altinbas) were grafted onto two commercial Cucurbita rootstocks (Kardosa and Nun9075). Plants were grown in aerated nutrient solution under deep water culture (DWC) at two electrical conductivity (EC) levels (control at 1.5 dS m−1 and salt at 8.0 dS m−1). Hydroponic salt stress led to a significant reduction in shoot and root growths, leaf area, photosynthetic activity, and leaf chlorophyll and carotenoid contents of both grafted and nongrafted melons. Susceptible plants responded to salt stress by increasing leaf proline and malondialdehyde (MDA), ion leakage, and leaf Na+ and Cl− contents. Statistically significant negative correlations existed between shoot dry biomass production and leaf proline (r = −0.89), leaf MDA (r = −0.85), leaf Na+ (r = −0.90), and leaf (r = 0.63) and root (r = −0.90) ion leakages under salt stress. Nongrafted Citirex tended to be more sensitive to salt stress than Altinbas. The Cucurbita rootstocks (Nun9075 and Kardosa) significantly improved growth and biomass production of grafted melons (scions) by inducing physiological (high leaf area and photosynthesis), biochemical (low leaf proline and MDA), and nutritional (low leaf Na+ and ion leakage and high K+ and Ca++ contents) responses under salt stress. The highest growth performance was exhibited by the Citirex/Nun9075 and Citirex/Kardosa graft combinations. Both Cucurbita cultivars have high rootstock potential for melon, and their significant contributions to salt tolerance were closely associated with inducing physiological and biochemical responses of scions. These traits could be useful for the selection and breeding of salt-tolerant rootstocks for sustainable agriculture in the future.

The aim of the present study was to find out whether grafting could improve salinity tolerance of melon plants, and whether possible induction of tolerance to salinity was linked with the defense of the photosynthetic apparatus. The climate chamber experiment was carried out to determine main stem length, leaf chlorophyll index (SPAD), fresh weight of shoot and root, and root length. Under climate chamber conditions, two melon cultivars [galia type Citirex F1) and standard type (Kirkagac Manisa Altinbas)] were grafted onto two different commercial Cucurbita maxima x C. moschata hybrid rootstocks (Kardosa and Nun 9075) and grown in 8 L pots filled continuously with aerated nutrient solution under two different salt levels (1 and 8 dS/m) with three replications. The results indicated that grafted and un-grafted plants were significantly (P<0.001) affected by different salt levels. Grafted plants had better growth performance than un-grafted plants under both control and saline conditions. The SPAD value of the un-grafted plants significantly decreased as salinity stress increased, while root fresh weight of the grafted plants significantly increased under salinity stress. Under saline conditions the highest shoot fresh weight, and SPAD value were recorded in graft combination Nun 9075/ Citirex. These results suggest that the use of salt tolerant Cucurbita maxima x C. moschata hybrid rootstocks can improve crop performance in melon under salt stress, whereas the appropriate scion/ rootstock combinations under saline conditions will be investigated for fruit yield and quality parameters in further studies.

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Aim:Methodology: Results: Interpretation:Three different seedling types that are bare rooted, ENSO and polyethylene containerized seedlings are mainly used for Cedar afforestation in Turkey, however research on long-term field performance of these seedling types is meagre. The present study aims at comparing the survival and growth rate in order to determine the best seedling types for afforestation and also exploring their economic value at different sites.The study was carried out at two different experimental sites in Burdur-Bucak-Urkutlu and Antalya-Korkuteli-Yelten. A randomized block design with six blocks and three seedling types was applied at each site. One-year-old seedlings were planted within the sites and observed for 13 years. Data collected in the last seven years were used for statistical analyses. Analysis of variance was performed at each site and different seedling types were compared through Duncan's multiple range tests.Results showed that there were significant differences between the seedling types at P<0.05 level for survival and P<0.01 level for growth rate. At both sites, the containerized seedlings had higher survival rates than the other seedling types.At Yelten, the containerized seedlings had 39% and 28% higher growth rates than ENSO and bare rooted seedlings. These rates were 21% and 17% at Urkutlu site, respectively. Afforestation investment costs for the containerized seedlings were also 23.9% and 15.4% higher than for the bare rooted and ENSO stock at Yelten and 27.6% and 20.6%, respectively, in Urkutlu.The results showed that containerized seedlings can be suggested for afforestation at similar sites considering their higher growth performance, even if the costs are higher than those of other types.