MOLECULAR COMPARISON OF WILD AND COMMERCIAL CHILIES FROM TAMAULIPAS AND TABASCO, MEXICO GUILLERMO CASTAÑÓN-NÁJERA1*, MOISÉS RAMÍREZ-MERAZ2

Abstract

The genetic differences among two groups of varieties of chili (Capsicum spp.) from different geographical origins (one each from the states of Tabasco and Tamaulipas in the Mexican republic) were studied using AFLP (Amplified Fragment Length Polymorphism) molecular markers. Four Tabasco chili varieties were studied; two cultivars (Jalapeño, Habanero) that belong to Caspicum annuum L. and Capsicum chinense Jacq., respectively and two wild varieties (Amashito, Ojo de cangrejo), that belong to Capsicum annuum var. glabriusculum. Five Tamaulipas chili varieties were studied: the Mirador, Piquín huasteco and Ozulamero varieties, which belong to Capsicum annuum L, and the Pico paloma and Chilpaya tabasco varieties, which belong to Capsicum frutescens. For the analysis of genetic differentiation, four AFLP molecular markers were used, which amplified 150 to 209 bands in the two variety groups. The AMOVA (Analysis of molecular variance) results indicated that the maximum variation was found between the regions (37.0%) and within the populations of each region (37.0%). The estimated variety differentiation was high, FST=0.373, which indicates that 62.70% from the variation is found within the varieties, and the high values of FIS=0.409 and FIT= 0.629 lead to the assumption that the varieties possess a large number of homozygotes and a substantial loss of heterozygotes. The cluster analysis separated the evaluated varieties by geographical region and by kind; for Tabasco, the wild Amashito and the Ojo de cangrejo were grouped, and the cultivated varieties formed their own group. In the Tamaulipas varieties, this grouping tendency was not observed.