FORAGE YIELD AND SILAGE NUTRITIONAL QUALITY IN NATIVE AND HYBRID MAIZE (Zea mays L.): RESPONSE TO A SEEDING DENSITY GRADIENT

The livestock sector can utilize native maize (Zea mays L.) varieties as an alternative source of feed for livestock during the dry season. However, their capacity to withstand high planting densities has not been fully evaluated. The objective of this study was to evaluate the agronomic and forage performance, as well as the nutritional quality of silage produced from the native maize varieties Crema Carrillo Puerto and Criollo Tezonapa, compared with the hybrids HV-570, H-518, and Imparable, at planting densities of 15 625, 50 000, and 90 000 plants ha-1. Planting was established in a completely randomized block design with a split-plot arrangement and four replications. The variables evaluated included days to male (MF) and female (FF) flowering; leaf width (LW), length (LL), and number of leaves (NL); plant height (PH), stem diameter (SD), and green forage yield (GFY). In addition, the dry matter, moisture, ash, fat, fiber, protein, and nitrogen-free extract contents of the corn silage were calculated. Data were analyzed using the GLIMMIX procedure of SAS, and treatment means were compared using the least significant difference (LSD) test at α = 0.05. The native maize variety Crema Carrillo Puerto reached female flowering (FF) 76 d after sowing (DAS), whereas the hybrids reached FF at 64 DAS, 12 d earlier than the native maize varieties. At a density of 90 000 plants ha-1, Crema Carrillo Puerto showed greater plant height (226.67 cm) and stem diameter (1.91 cm). In contrast, at the same plant density, the Criollo Tezonapa variety showed higher values for leaf length (106.65 cm) and a greater number of leaves (14 leaves per plant). Criollo Tezonapa showed a higher green forage yield (36.93 Mg ha-1) and a crude protein content similar to that of the hybrids. These results indicate that native maize varieties can be successfully incorporated into intensive forage systems for the production of high-quality silage, demonstrating the adaptability of these genotypes and supporting their diversification of use and conservation.