FORAGE AND GRAIN YIELD, AND SILAGE QUALITY OF HYBRID MAIZE IN TULANCINGO VALLEY, MEXICO

The experiment was established in a complete randomized blocks design. Data were analyzed with SAS GLM procedure and Tukey test (P <= 0.05) for comparison of means. The AMMI model was used with principal components to detect stability response in environments. The H443A hybrid produced higher forage yield (P <= 0.05) on a dry basis (24.0 t ha(-1)) in the loclity of Cebolletas. There were highly significant maize material x location interactions (P <= 0.001). In the silages there were differences (P <= 0.001) between hybrids in the percentage of neutral and acid detergent fiber, starch and net lactation energy. The highest grain yield was obtained with the Cherokee hybrid in Cebolletas (7404 kg ha(-1)) and it was consistent in all four sites (P <= 0.05). The highest weight of 200 grains in the four localities was observed in the hybrid H13 (62.3 g, P <= 0.05), while the largest volumetric weight was obtained with H78 (83.2 kg hL(-1), P <= 0.05). The green and dry forage yield of maize hybrids recommended for altitudes below 2000 masl exceeded those recommended for altitudes above 2000 masl; however, they had lower grain yield (P <= 0.05). The maize hybrid H443A is useful for silage, while Cherokee and Caribu can be useful for forage and grain.