Morphological diversity of ancho chile pepper landraces from Mexico

Abstract Ancho (width) chile peppers have economic, social, culinary and cultural importance in Mexico and worldwide. This chile type considers divergent subtypes that altogether have not been analysed and therefore their morphological diversity has not been systematically described. The objectives were to describe the morphological diversity of ancho pepper landraces from Mexico, to identify groups of similarity and to define the traits with the higher contribution to the total variation. Eighty-six landraces of ancho chile peppers (red, ‘mulatos’, ‘miahuatecos’, ‘cristalinos’ and ‘huacle’), collected in six states of Mexico, and two commercial controls were evaluated in two localities, in a simple randomized complete block experimental design. We recorded 76 morphological traits. Statistical analysis included a combined ANOVA, Pearson's correlation coefficient, discriminant analysis, principal components and clusters. The morphological diversity in ancho chile peppers was mainly made up of fruit width, fruit wall thickness, stem diameter, corolla length, seed weight per fruit, plant height, stem length and pubescence. We defined four groups, which made it possible to differentiate ancho chile peppers of Puebla and the huacle chile pepper of Oaxaca from populations collected in the north and ‘Bajío’ (midland) parts of Mexico. Ancho chile peppers of Mexico showed wide morphological differences according to the type of chile pepper and seed collection regions. The traits that contributed the greatest morphological diversity were fruit width, fruit wall thickness, stem diameter, corolla length, seed weight per fruit, plant height, stem length and pubescence.