S11 - Session P5 - Screening local landraces of melon for resilience to salinity stress under hydroponic greenhouse conditions

Authors: Theodora Ntanasi *, Georgia Ntatsi, Ioannis Karavidas, Georgios Outos, Georgios Maloukos, Vasileios Fotopoulos, Dimitrios Savvas

Water shortage and heat driven evaporation in semi-arid climate, such as Mediterranean, are mainly ascribed to climate change, introduced salinity as a major stress factor in vegetable crop production. Thus, the adaptation of vegetables, especially those susceptible to osmotic stresses, is becoming more and more challenging to acquire sustainable cropping systems in saline environments. The aim of this work was to screen different melon genotypes for resilience to salinity. Within this frame, four melon landraces were exposed to salt stress to evaluate their tolerance, in respect of yield and fruit quality, against to the current widely cultivated Spanish variety "T111 (tipo piel de sapo)" and the commercial hybrid "Lavigal" that served as control. The above experiment was carried out at the greenhouse facilities of the Laboratory of Vegetable Production at the Agricultural University of Athens, where the different melon genotypes were hydroponically cultivated in an open system with perlite as substrate, by applying a nutrient solution of 0.5 mM NaCl at the non-saline treated plants and 30 mM NaCl at the salt-exposed plants. To investigate the impact of the above stress on fruit quality, parameters such as diameter, the values of Hunter color parameters (a*/b*), titratable acidity were determined. In addition, fruit yield and dry matter content in fruits were also assessed. The results of this study showed that the yield of all under study genotypes was restricted under saline stress. However, the reduction in yield was accompanied by enhanced quality performance of fruits, except for variety "Tendra negro". In addition, the landrace "Thrakiotiko" were less benefited compared to the rest genotypes, as the only positive effect of saline stress was recorded on dry matter content of fruit.