Morphological Characterization of Southern Jalisco, Mexico, Pomegranate Genotypes Using AFLP Markers

Pomegranate is gaining popularity because of its proved nutraceutical properties and is highly adaptable to different climates. In southern Jalisco, Mexico, 18 genotypes were characterized on the basis of fruit characteristics (21 traits) and AFLP (Amplified Fragment length polymorphism) markers. The first three components of a principal components analysis (PCA) explained 71.5% of the variation. The most important variables were related to fruit size and weight. Fruit weight, equatorial diameter, polar diameter, and rind and membrane weight were the variables that most contributed to principal component one (PC1) 46.4%. The variables juice per fruit, edible proportion, proportion of rind and membrane, and seed length contributed most to principal component two (PC2) 15.2%, while juice pH, weight of one seed, and aril width contributed the most to principal component three (PC3) 9.9%. With the six combinations of AFLP primers, 315 fragments were obtained (an average of 52.5 fragments per primer); of these, 229 were polymorphic (72.7% polymorphism). Grouping by both morphological traits and AFLP markers separated all the evaluated individuals so that there were no repeated genotypes. In both analyses, the grouping did not obey geographic origin of the genotypes (r = -0.35), suggesting that both techniques were useful and complementary in the characterization of pomegranate genotypes. The commercial cultivars Wonderful and Apaseo had low levels of similarity to genotypes from southern Jalisco. The level of polymorphism found and compared with the results obtained by other authors suggests that the pomegranate genotypes evaluated are highly polymorphic. We found broad genetic diversity that can be used in breeding programs.