DIVERSITY AND CONSERVATION OF LOCAL MAIZE FROM LA FRAILESCA, CHIAPAS, MEXICO

La Frailesca is the second largest region of Chiapas, Mexico, with more than 200 communities where there is a constant exchange of seeds and knowledge about the uses and management of local varieties of maize (Zea mays L.); in addition, it has a varied structure of microenvironments that allows the presence of a diversity of agroecological systems that favors the existence of genetic diversity in maize. The objective of this sudy was to know the diversity of local maize that is still conserved in the six municipalities of the region. Collections were carried out from December 2016 to March 2017 by field trips, applying the sampling-network method to locate the farmers who still plant them. The varieties collected were characterized through nine morphological characters of ear and kernel. The greatest morphological variation was found in the kernel row number of the ear, ear diameter, cob diameter, ear shape and kernel shape. Amarillo maize from El Parral and Amarillo from Montecristo de Guerrero presented the highest number of kernel rows (18) and Senorita Blanco maize from Montecristo de Guerrero had eight rows. The Mezcla de Villa Corzo variety presented an ear diameter of 5.9 cm, the minimum value for this trait was observed in Olotillo-Amarillo from El Parral with 3.1 cm. Positive correlations were observed between kernel row number of the ear, cob diameter, ear shape and kernel length with ear diameter (0.75, 0.79, 0.36, and 0.61, respectively). From the principal component analysis, five phenotypic groups associated with the Tuxpelio, Olotillo and Comiteco races were defined as predominant, which describes the morphological pattern of the studied local maize, and the genetic variability that exists in the Frailesca region, Chiapas, Mexico.