Emergence and early growth of Peltophorum dubium (Spreng.) Taubert seedlings under different substrata

This work carried out to determine substrate for germination and vigor tests of Peltophorum dubium (Spreng.) Taubert seeds. The experiment was carried out in a greenhouse of the Laboratory of Vegetal Ecology of the Centro de Ciencias Agrarias of the Universidade Federal da Paraiba, Northeast Brazil. Were compared the substrates sand (T-1); sand + vermiculite in the ratio of 1:1 (T-2), 3:1 (T-3) and 1:3 (T-4); vegetal soil (T-5), vegetal soil + sand in the ratio of 1:1 (T-6), 3:1 (T-7) and 1:3 (T-8), vegetal soil + vermiculite in the ratio of 1:1 (T-9), 3:1 (T-10) and 1:3 (T-11), vermiculite (T-12), bioclone (R) (T-13), bioplant (T-14) and plugmix (R) (T-15). The design used was entirely randomized with 15 treatments (substrates) and four repetitions of 25 seeds. The evaluation was made through the determination of: percentage of emergency, first counting, index of speed, average time and relative frequency of emergency, length and dry mass of the root and aerial part of seedlings. The results evidenced that the substrates pure commercial vermiculite, bioclone, bioplant and plugmix, well as the mixture sand + vermiculite in the ratio of 3:1, vegetal land + sand in the ratio of 1:1 and vegetal soil + vermiculite in the ratio of 1:3 are less efficient for conduction of germination tests with seeds of P. dubium, while the substrate sand + vermiculite in the ratio of 3:1 is most efficient in detecting differences of vigor in the seeds of the different treatments.