Genotypic variation in the response of watermelon genotypes to salinity and drought stresses

10th EUCARPIA Meeting on Genetics and Breeding of Cucurbitaceae -- OCT 15-18, 2012 -- Antalya, TURKEYWOS: 000345687100052In this study, salinity and drought responses of 65 watermelon genotypes have been investigated in early plant growth stage. The plants were grown in vermiculite culture with 200 mM NaCl for salinity stress and irrigation was stopped gradually for terminal-drought stress. Control plants without stress have also been grown. Young plants (24 days old plant) were used for screening studies. Physiological measurements and analysis were conducted to identify tolerant versus susceptible watermelon genotypes; A scale evaluation of 0-5 for symptomatic appearance of the plants, shoot fresh and dry weights, root fresh and dry weights, leaf number per plant, leaf area, SPAD-Chlorophyll meter reading, membrane injury index, leaf relative water content, leaf water potential, leaf osmotic potential, stomata conductance, leaf temperature, Na, K, Ca, and Cl concentrations of the shoot and root samples. For each parameter, differences in salinity and drought stresses compared to control have been calculated. At the end of the study, large variations have been determined in watermelon genotypes for their salinity and drought responses. The sixty-five watermelon genotypes were classified as tolerant, mildly tolerant or susceptible.European Assoc Res Plant Breeding, Cukurova Univ, Minis Food, Agr & Livestock, Turkish Sci & Technol Council, Antalya Tarim, Manier Seed, Yuksel Seed, Syngenta, AG Seed, Fito Seed, Multi Seed, Nunhems, Rijk Zwaan, Bati Akdeniz Agr Res Inst, Alata Hort Res StatUNDP [MDG- F 1680]; Cukurova UniversityCukurova University [ZF2009KAP7, ZF2010KAP1, ZF2011KAP3, ZF2010YL49]The authors want to thank to the UNDP ( United Nation Development Programme) for supporting our work with " MDG- F 1680 UN joint programme on enhancing the capacity of Turkey to adapt to climate change". Many thanks also Cukurova University for the financial supports of ZF2009KAP7, ZF2010KAP1, ZF2011KAP3 and ZF2010YL49 projects