POLIBOTÁNICA, year 25, no. 50, July 2020, is a biannual journal published by the National Polytechnic Institute, through the National School of biological sciences. Professional Lázaro Cárdenas, prolongation of Carpio and Plan de Ayala unit s/n, Col. Santo Tomas C.P. 11340 delegation Miguel Hidalgo Mexico, CDMX. phone 57296000 ext. 62331 http://www.polibotanica.mx, Chief Editor: Rafael Fernández Nava. Reservation of rights to the exclusive use of the title no. 04 - 2015-011309001300 - 203. ISSN: 2395-9525, both awarded by the National Institute of copyright. Responsible for the latest update from this number, unit of Informatics of the ENCB of IPN, Rafael Fernández Nava, unit professional Lázaro Cárdenas, prolongation of Carpio and Plan de Ayala s/n, Col. Santo Tomas C.P. 11340 delegation Miguel Hidalgo Mexico, D.F., the last modified date of July 15, 2019. The views expressed by the authors do not necessarily reflect the position of the editor of the publication. It is strictly forbidden the total or partial reproduction of the contents and images of the publication without prior authorization from the National Polytechnic Institute.