The objective of this research was to study the immediate effect of drying delay of
annual ryegrass seeds (Lolium multiflorum Lam.), cv. Comum-RS, on their physiological quality.
Treatments of harvest (seeds with moisture contents of 38.2, 35.0 and 27.8%) and periods of
drying delay (zero, two, four, six, eight, 12, 18, 24, 36 and 48 hours), in completely randomized
split plots, with two replications, were compared. Seeds were placed in 18 polystyrene boxes,
each with 24kg. Seeds were dried on a shadowy concrete floor for 12 hours and drying was
completed in an oven (35ºC) with forced air circulation. Moisture content, germination, vigor
(five-day germination and accelerated aging tests) and 1000-seeds weight were evaluated. Results
allowed to conclude that: seeds of annual ryegrass present a period of tolerance to drying delay,
after witch physiological quality fails strongly; period of tolerance and deleterious effect of seeds
drying delay on their physiological quality change according to interaction of moisture content
and temperature of seed mass; temperature and/or moisture content decreasing allows to prolong
the period of drying delay.