Resumo

GAYTAN-BAUTISTA, Rodolfo; MARTINEZ-GOMEZ, Ma. Isabel  e  MAYEK-PEREZ, Netzahualcóyotl. Grain and forage yield in maize hybrids and their advanced F₂ generation. Agric. Téc. Méx [online]. 2009, vol.35, n.3, pp.295-304. ISSN 0568-2517.

To cope with the high seed cost of maize hybrids, small-scale farmers use F₂ and F₃ seed. The objective of this study was to determine the effect of using seed from self-pollinated hybrids on grain and forage yields of maize hybrids. The study was conducted under irrigated conditions at Tepezalá and Pabellón de Arteaga, Aguascalientes, and Calera de Victor Rosales, Zacatecas, Mexico during 2001. Twenty-two commercial hybrids and their respective advanced F₂ generation were sown under a split split plot arrangement in a complete random block design with three replications. Grain and forage yield, plant height, days to masculine and feminine flowering and husk height were determined. A profit/cost analysis was performed. On average, the use of F₂ seed diminished 22% grain and 8% forage yields. Most of the hybrids and their advanced generations did show grain and dry forage yield stability across locations. Due to generational advance, the profit/cost ratio diminished 9% for grain production and increased 11% for dry forage production. Hybrids SB-302 and AS-948 showed high grain and dry forage yields, less reduction with the advance of generation and high profit/cost ratios.

Palavras-chave : Zea mays L.; F₁ and F₂ hybrid generations; profitability.