COMPARISON OF DNA FINGERPRINTS IN LEAVES AND FRUITS OF Capsicum spp.: INFERENCE OF CROSS-POLLINATION

Abstract

The Capsicum genus comprehends five species that are mostly cultivated (C. annuum L., C. chinense Jacq., C. frutescens L., C. baccatum L. and C. pubescens). México occupies the second place in world production, with the C. annuum crop being of greater economic, cultural and social importance. DNA fingerprints in leaf and fruit of two varieties of C. annuum (Jalapeño and Serrano) and one variety of C. pubescens (Manzano) were compared with ISSR gene markers, in order to estimate the degree of crossing that took place in different environments in experimental plants. For each PCR primer, 32 to 44 amplicons were obtained, and in total 76 fragments of different molecular weights were considered to carry out the analyses. The PIC, MI and Rp values were 0.75, 0.70 and 18.8 for leaf, and de 0.67, 0.62 and 20 for fruit. With the Iso_1 primer the percentages of polymorphism obtained were 91.3 % for leaf and 87 % for fruit from the same plant. The ISSR markers allowed estimating the percentage of cross-pollination, thus comparing the genetic information of leaf and fruit structures in Capsicum spp., which can accelerate the plant improvement process, also permitting to differentiate the three pepper varieties, separate the cultivars and estimate the level of pollination that took place under experimental conditions.