ABSTRACT
Acacia mearnsii De Wild is an economically and socially important species for the State of Rio Grande do Sul. The seedlings of that specie are producted with seeds, which have a hard seed- coast. The effect of different methods to overcome dormancy, and the best photoperiod for the germination of the seeds were determined. Usually the hot water immersion is used to overcome dormancy of black wattle seeds. However, the storage of the seeds is compromise due to the slow drying process wherever the air moisture is high. The scarification of the seeds and the hot water were compared. Also, four photoperiods were tested: 16 hours under fluorescent lighting, 12 hours under fluorescent lighting, 24 hours under fluorescent lighting, and 24 hours in the dark. The seeds were placed in plastic germination boxes, with sterile vermiculite, and were incubated at 25°C. The germination was evaluated 7, 14 and 21 days after seeding. The hot water with temperature de 80°C was 15% superior to the scarification method. Germination was higher when the seeds were incubated under 12 hours of fluorescent lighting.
Keywords:
dormancy; sacrification; luminosity