¿Cómo impacta la fecha de siembra sobre la aptitud granífera y forrajera en maíz?

YÉSICA DANIELA CHAZARRETA; SANTIAGO ALVAREZ PRADO; MARIA ELENA OTEGUI

Pergamino

Congreso; XII Congreso Nacional de Maíz; 2022

INTA - UNNOBA - AIANBA

Late-sown maize (Zea mays L.) crops represent 50 % of the current maize area in Argentina. Themain goal of this work was to evaluate the effect of late sowing dates on grain and forageaptitudes in a set of eight commercial maize hybrids when grown under contrasting sowing date× year environments in the Central Pampas region. Grain yield, harvest index, grain dry-down,fresh biomass, and duration of the chopping window for whole-plant silage were measured toevaluate grain and forage aptitudes. Grain yield was maximized in early (2019/2020) as well aslate sowing dates (2020/2021), whereas the harvest index was always higher in the early sowingdates. In early sowings, both kernel desiccation rates (before and post physiological maturity)were highest (in absolute values). Hybrids differed in their kernel desiccation rates. The choppingwindow occurred earlier (32 – 46 days after silking) and was shorter (13 days) in early than in latesowing dates (46 - 66 days after silking and 21 days, respectively). Fresh biomass production washigher in the late sowing date environments than in the early ones. Thus, the best genotype forgrain yield is not necessarily the best one for forage yield, as suggested by the change of rankingbetween hybrids depending on the environment and the crop final usage.