Molecular characteristics of prickly-pear cactus (Opuntia) based on internal transcribed spacer sequences (ITS) of Queretaro State-MexicoM.C.C.P. de Lyra, D.C. Santos, C. Mondragon-Jacobo,M.L.R.B. da Silva, A.C.E.S Mergulhão and E. Martínez-Romero3_pdf.pdf006-010Opuntioideae,Taxonomy,Hybrid,molecular markers,prickly-pear cactus881294The prickly-pear cactus has great importance in the human feeding in Mexico and also for export of fruits. Around 8 000 years ago in Mexico, Opuntia was domesticated for human consumption took place. The high capacity of prickly-pear cactus for vegetative propagation has contributed to its wide-spread distribution, even to the extent of becoming a weed. In secondary diversification areas of introduction, the genotypic and phenotypic characteristics of Opuntia were modified. Studies using biosystematics and morphology demonstrated a relationship with other Opuntoideae. The internal transcribed spacer region nuclear ribosomal DNA was sequenced in seventeen species for phylogeny. These findings indicate that the ITS region in Opuntoideae should be further exploted as a promising source of nuclear phylogeny markers. Opuntia ficus-indica (L. Mill),, Opuntia robusta, Opuntia albicarpa, Opuntia streptacantha they are not well characterized in this study, them of they contain in way its would arbitrate. The need of larger studies with molecular and morphologic markers in these species is very important.. The results of phylogeny analysis of Opuntia species suggests a new revision in the taxonomy of these plants sees that, the presence of hybrid in this study demonstrates the difficulty of characterizing in a safe way the species of the family Opuntiodeae.