The Differences Among Melon Genotypes and Varieties Under Salt Stress Based on Certain Morphological and Physiological Properties - Mixture Modeling and Principal Component Analysis (Pca)

Abstract

Present study aimed to determine the effects of salt stress in 13 melon genotypes and 4 commercial melon varieties collected from the Van Lake Basin. Two doses of salt applications were conducted at 0 mM and 50 mM NaCl concentrations and the plants were cultivated in 3 repeats under 25 +/- 2 degrees C temperature and 16/8 light/dark periods based on the randomized block experimental design in climate chamber conditions. In order to determine the effect of stress, traits such as 0-5 scale, shoot and root lengths, shoot diameters, leaf number, fresh and dry weights of shoots and roots, leaf relative water content, membrane injury index, stoma widths and lengths, stomatal areas and stoma densities were evaluated. The reaction of the genotypes against stress was determined via mixture modeling and PCA analysis. In PCA analysis, three PCA components explained 71.48% of the total variation at 0 mM, while four components explained 69.53% of the total variation at 50 mM. As a result of the mixture modeling analysis, it was observed that 4 sub-populations for 0 mM and 3 sub-populations for 50 mM were formed and it was revealed that the salt-tolerant genotypes were in the sub-population 3 and salt-susceptible genotypes were in the sub-population 1.