CHARACTERIZATION OF OUTSTANDING MAIZE POPULATIONS OF THE ZAPALOTE CHICO RACE

Abstract

The Zapalote Chico race of maize (Zea mays L.) is an important component of the genetic diversity of this species in the Tehuantepec Isthmus region, Oaxaca, Mexico. This race raises interest among local farmers and researchers for preservation and dissemination purposes. Safeguarding plant genetic resources is of relevance to ensure Mexican food sovereignty. Under the context of climate change, the agronomic characteristics and virtues of Zapalote Chico constitute a  viable option to be considered in national and international breeding programs. The objective of the present study was to perform a morphological characterization of 18 outstanding landraces of the Zapalote Chico race to determine the degree of the extant variability. Sixteen quantitative and nine traits of the plant, tassel and ear were recorded. The analysis of variance of the quantitative traits showed highly significant statistical differences in 13 traits and in two the difference was significant. In the principal component analysis the first three components accounted for 59.06 % of the cumulative variance; the characters with the greatest descriptive value of phenotypic variability between the populations evaluated were the ratio between the height of the upper ear and plant height, plant height, ear height, number of kernel rows, ear diameter and tassel central axis length. The accessions that contributed the most to variability were ZAP-MOR, OAX-827, OAX-832 and COL-51. Similarity was more evident in populations from higher and lower altitudes, as those from the intermediate altitude were markedly separated, which may be due to the fact that they are from the study location and were tested at the same place.