Effect of deep of sowing and light intensity on germination of 'baru' seeds (Dipteryx alata Vog.)

Abstract

Effects of five deeps of sowing and two light intensities on germination of "baru" seeds have been studied. Seeding was done in plastic pots of 22.5 cm of diameter by 18.5 cm of height, filled with washed sand, at 0, 1, 2, 3 e 4 cm of deep and light intensities were 100% of natural light, in an open field nursery, and 50% of natural light, in an woven nylon covered lath house. Light conditions, deeps of sowing, and their interaction affected seed germination rate and speed of germination. Germination rates averaged 72.8% and 52.5%, and speed of germination were 17.1% and 11.1% seeds germinated per week, at 100% of light and 50% of light, respectively. Deeps of 1, 2 and 3 cm have been found to be the best ones with germination rates of 79.4%, 81.9%, and 78.8% and speeds of germination of 18.4%, 19.2%, and 17.5% of seeds germinated per week, respectively. Interaction have been found to be significant at 0 cm of deep, where both germination rate and speed of germination, only at this deep, where better at the 50% of light. In conclusion, baru seeds should be planted from 1 to 3 cm of deep at 100% of light intensity, to get the best results on final germination and speed of germination.