Use of Multivariate Statistical Analysis for Group Selection of Genotypes of two Segregating Populations of Melon

Cantaloupe is one of the most important vegetable crops in Iran. In recent years, due to some problems, such as low sweetness and fruit yield, plant death diseases, and the indiscriminate introduction of foreign commercial hybrid cultivars, the genetic resources of this product have been severely eroded. Therefore, in this research the crossing of important local cultivars such as Saveh and Niagara with the commercial and selected F1 cultivar Galia was considered to combine the best traits and select the best genotypes of the F2 generation by pedigree selection method and continuity of generations. This experiment was carried out in the Faculty of Agricultural Technology (Aboureyhan Campus) University of Tehran research farm. The selection of the best genotypes was done in three stages (natural screening in the field for disease, virus, and mite resistance, evaluation based on qualitative traits in the laboratory, and final selection of genotypes based on the results obtained from multivariate analysis of quantitative traits). The results showed that in Niagara × Gallia (NGF2) population, general heritability was high for all the evaluated traits except the fruit shape index. In the Saveh × Gallia (SGF2) population flesh thickness, soluble solids and fruit harvest date had the highest heritability. The results showed that the traits included in the stepwise regression model accounted for 90.3 and 80.3 percent of the total changes related to fruit weight in NGF2 and SGF2 populations, respectively. Based on the principal component analysis, in NGF2 and SGF2 populations, two principal components explained 71.88 and 71.31% of the data variance, respectively. Based on the results of the bi-plot analysis, 30 NGF2 and 53 SGF2 genotypes were selected, and cultivated in order to continue generations and reach pure parental lines in the F3 generation.