DISTRIBUTION AND DIVERSITY OF NATIVE MAIZE VARIETIES (Zea mays L.) IN THE HIGHLANDS OF TAMAULIPAS, MÉXICO

Abstract

The center-south region of Tamaulipas, México, is characterized by presenting diversity of native maize varieties (Zea mays L.), which have not been explored or studied sufficiently and whose populations should be collected for their conservation, characterization and exploitation in genetic improvement programs. The objective of the study was to explore and analyze the genetic diversity in the highlands of Tamaulipas, with the aim of understanding the distribution and morphological variation of native maize varieties. The collections were made from June 2016 to January 2017. Ninety-one (91) populations were obtained for their characterization and the passport data from each accession were recorded. Ten representative corncobs were used from each accession to obtain information about the quantitative traits of each population; then the racial identification of each collection was performed by classifying experts based on the characteristics of the corncob. A principal components analysis was used to group the races in function of the variables evaluated, and the two first principal components explained 57.3 % of the total variation. Of the accessions, 67.4 % were found in localities of intermediate altitudes (landraces: Celaya, Chalqueño, Elotes Occidentales, Olotillo, Ratón, Tabloncillo, Tuxpeño Norteño and Vandeño). Eleven native races were identified, and the predominant race was Ratón with 43 populations.