The aims of this paper were to develop protocols to obtain in vitro seedlings of P. taeda, evaluate the use of alternative substrates as well as analyze the effect of pre-germinative treatments for optimizing germination. Disinfestation treatments using sodium hypochlorite, influence of photoperiod and pre-germinative treatments, and the possibility of using alternative substrates (maize starch, filter paper, hydrophile cotton, vermiculite, agar-water and addition of activated charcoal into the nutritive medium) were tested for germination. In vitro germination, fungal and bacterial contamination were evaluated. The best seed disinfestation treatment was ethanol at 70 % for 30 seconds + sodium hypochlorite at 3 % for 5 minutes. However, it caused a toxic effect. Alternative substrates provide adequate physical conditions to tissue culture, but do not favor germination. Nevertheless, the use of hydrophile cotton associated with seed soaking for 72 hours, without disinfestation, enhances germination and provides in vitro seedlings with low contamination.
Seed desinfestation; Tissue culture and Alternative substrates
