Pinus taeda L. is the main forest tree species planted in Southern Brazil and its wood is used for sawlogs, venner, particle board, medium density fiberboard (MDF), pulp and paper industries. Due to its high economic importance, interest exists in developing techniques for vegetative propagation aiming at mass multiplication. The purpose of the present work was to evaluate the effect of the age of seedlings used as mother plants (60, 90, 120 and 150 day-old) and of the four seasons of the year on rooting of P. taeda minicuttings. Minicuttings of 5 cm in length were collected from herbaceous branches and treated with Captan® solution (0.1%). Minicuttings were planted in plastic tubes containing Mecplant® substrate overlayered with vermiculite. Minicuttings were maintained in greenhouse for 120 days with temperature between 15 and 25ºC and 90% relative humidity. The parameters evaluated were: percentage of rooted, surviving and dead minicuttings, length of the three larger roots, number of roots and minicutting dry weight. Seedling age influenced the rooting percentage, and the highest value (85%) was obtained with 60-day-old seedlings. The winter was the most favorable season for the collection of minicuttings.
Rooting; season; age
