Molecular characterization using ISSR primers of Magnolia mexicana DC. from two regions in Zongolica, Veracruz, Mexico

Introduction: Magnolia mexicana DC. is a threatened species according to NOM-059-SEMARNAT-2010, a situation attributed to the fragmentation and destruction of its habitat. There are no studies on the genetic diversity of M. mexicana, even though it is endemic to our country. Objective: To evaluate genetic variability in two M. mexicana populations using ISSR molecular markers. Materials and methods: The collections come from Amatitla and Zapotla in Zongolica, Veracruz. The DNA was extracted from the young leaves. A total of 55 ISSR primers were tested; the 10 that produced the highest number of polymorphic bands were selected and amplified by PCR. Results and discussion: The ISSR primers showed 86 % polymorphism. Cluster analysis, using Ward's minimum variance method, was able to separate the collections by their geographical origin. Analysis of molecular variance showed that the greatest variability (90.88 %) is found within each population. The Shannon-Weaver diversity index was 0.47 and 0.41 for Amatitla and Zapotla, respectively. Conclusion: The M. mexicana populations have not undergone changes in their genetic structure; there is no evidence at genetic level of alterations caused by population reduction or habitat fragmentation.