The aim of the trial was the injury on physiological quality evaluation of prechilling
treatment to overcome seed dormancy in annual ryegrass (Lolium multiflorum Lam.).
Storage periods (zero and seven months) and pre-chilling periods (zero, three, six, nine and 12
days) were studied in a factorial completely randomized design. Before germination test at 20ºC,
seeds were placed in a refrigerator, at 8±1ºC, as dormancy overcoming treatment. Besides
germination, dormant and dead seeds were also evaluated. Results allowed to conclude: dormancy
overcoming treatments used are not enough to total dormancy overcoming in annual ryegrass
seeds, immediately after harvest and drying; increasing pre-chilling period, more than nine days,
do not improve dormancy overcoming, immediately after harvest; six days pre-chilling treatment
overcomes closely all dormancy in seeds stored for seven months; pre-chilling causes stress in
seeds stored for seven months; according to age, seeds react differently to pre-chilling period
duration.