Resumen

PENA RAMOS, Alfonso; GONZALEZ CASTANEDA, Fernando  y  ROBLES ESCOBEDO, Francisco Javier. Agronomic management to increase grain and forage yield in full season maize hybrids. Rev. Mex. Cienc. Agríc [online]. 2010, vol.1, n.1, pp.27-35. ISSN 2007-0934.

The agronomic management of maize impacts grain yield and production and quality of forage. The objective was to determine the effects of two nitrogen levels and three plant stands upon grain yield and dry matter production, also on the forage quality of full season maize hybrids. The experiment was established on May 2003 in Aguascalientes, Mexico. The experimental design was a completely random with split-split plots, in large plots N levels, 180 and 240 kg ha^-1, were tested; in medium plot plant stands, 60 000, 80 000 and 100 000 plants ha^-1 and the hybrids H-376 and Lobo in the small plots. The recorded variables were: grain yield per ha and total dry matter production, neutral and acid detergent fiber content, dry matter digestibility in vitro and milk production per ton of dry matter as well as per hectare. The 240-90-00-fertilization level increased grain yield and total dry matter in 1.3 and 3.3 t ha^-1 respectively. The increase in plant stand from 80 000 to 100 000 plants ha^-1 increased grain yield in 1 t ha^-1 and the change of 60 000 to 100 000 plants ha^-1 increased total dry matter in 3.2 t ha^-1. The H-376 had the greatest yield of total dry matter with 21.7 t ha^-1 and the largest contents of neutral and acid detergent fiber, and the lowest digestibility in vitro; nonetheless Lobo produced 216 kg of milk t^-1 and 3.5 t of milk ha^-1 more than H-376.

Palabras llave : late maturity hybrids; maize; nitrogen fertilizer; plant stand.