AGRONOMIC CORN HYBRIDS RESPONSE UNDER IRRIGATION AND RAINFED AT TWO SOWING DENSITIES IN HIGH VALLEYS OF MEXICO

Background. In maize production, irrigation water as an input with monetary value should increase the benefit; rain is the most sustainable source of water, but it does not ensure benefit. Objective. To evaluate the agronomic response of corn hybrids under irrigation and rainfed at two sowing densities. Methodology. The experiment design was factorial in complete randomized blocks and three repetitions with: genotypes (G) ten materials (G1…G10), two levels of humidity (H) such as irrigation (H1) and rainfed (H2), two planting densities. (D) with D1= 55 thousand plants ha-1 and D2=75 thousand plants ha-1, in two environments (A) in the State of Mexico; Cuautitlan (A1) and Texcoco (A2). Results. The general mean of grain yield was 7.1 t.ha-1 and water use 10.7 kg.mm-1. The results of these variables successively for the factors were: The hybrid (IA249AE X FSN 87) X GNF resulted with the highest means 8.9 t.ha-1 and 13.35 kg.mm-1; irrigation presented a higher yield of 7.39 t.ha-1, but rainfed was higher in water use with 11.41 kg.mm-1; Cuautitlán was higher with 9.4 t.ha-1 and 13.4 kg.mm-1; the D1 density was higher with 7.19 t.ha-1 and 10.75 kg.mm-1. The first-order interactions were significant, at least in one response variable. Implications: Additional research is required about water corn productivity to identify the potential of genotypes of corn in Mexico Basin. Conclusions. Rainwater availability had a greater effect than irrigation on corn hybrid grain yield and water use in Cuautitlán, and irrigation was less productive at that site. The higher population density responds to the availability of more resources such as water.