Efecto del momento de cosecha y la temperatura de secado sobre la emergencia y el vigor de semillas de maíz en siembras tempranas

JUAN SANTIAGO MARTIREN; DIEGO BATLLA

Congreso; IX Congreso Nacional de Maíz; 2010

High seed vigor is essential to obtain high corn yields under typical early planting dates exposed to low soil temperature. Due to the fact that harvest time and drying temperature can affect hybrid seed vigor parameters, quantifying the effect of these variables is of paramount importance for producing corn seed with high vigor. In this context, the objective of the present work was to evaluate the effect of harvest time and drying temperature on corn seed emergence and seedling vigor traits under low temperature conditions. To achieve this objective, final emergence percentage and seedling dry weight under early sowing conditions, were evaluated for seeds harvested between 42 and 16% seed moisture content and dried at high (50ºC) and low (35ºC) air temperatures. Obtained results suggest the existence of a “critical point” around the time of physiological maturity (PM) after which seeds dried at high temperatures achieved maximum percentage of emergence and maximum seedling dry weight (similar to that observe for seeds dried at low temperatures; 35ºC), and that the acquisition of this drying tolerance take place in a short time between 41 and 33% seed moisture content. These results highlight the importance of a correct estimation of PM for planning hybrid seed drying schedules to obtain high seed vigor, as is beyond this point (PM) that seeds could be dried in a wider range of temperatures without affecting their germination quality and vigor related traits.