PROTEIN, LYSINE AND TRYPTOPHAN IN NATIVE POPULATIONS OF MIXTECO MAIZE

Abstract

The landrace diversity of maize (Zea mays L.) in the Mixteca Oaxaqueña region in México is a response to natural and human selection pressures. In order to evaluate the protein, lysine and tryptophan content in the native Mixteca maizes, a collection of 70 population samples at 51 farmer communities belonging to 13 municipalities of the Tlaxiaco, Oaxaca district was determined. Populations were planted during the 2008 Spring - Summer agricultural cycle under a complete randomized blocks design with four replications at San Martín Huamelulpam. At harvest, a random 300 g kernel sample per experimental plot was taken and the protein, lysine and tryptophan contents were assessed. Significant differences (P ≤ 0.05) were observed among and within groups of accessions of Mixteca maizes with different kernel color (yellow, blue, white, red and color combinations) for the protein, lysine and tryptophan content in the whole kernel. Control and evaluated accessions of yellow, white, red kernel and color combinations of kernel color showed no significant differences in lysine and tryptophan content. In protein, 10 accessions surpassed the QPM control. Accession CIIDIR-185 is promissory since it presented similar values in tryptophan and lysine, and higher values in protein content in relation to the control.