This experiment was carried out to study the growth of Bombacopsis glabra (Pasq.) A. Robyns seedlings under different light intensities. The germination capacity of the seeds was determined by the index and percentage of germination speed of a hundred seeds (1 seed/sac). After 40 days, seventy-five saplings were transferred to 50% and 30% shade and beds under direct sunlight. Sapling development was carried out in randomized block design with three repetitions of five saplings, with stem height and lap diameter being evaluated on the 61st, 82nd, 103rd and 124th day after sapling emergence. Chlorophyll content a, b, total and ratio a/b; dry mass of the plant (DM), leaf area (LA), relative growth rate (RGR), leaf area rate (LAR) and net assimilating rate (NAR) and survival sapling percentage were measured on the 103rd and 124th days, when the experiment was concluded. The seeds presented 95% of germination and a high index of germination speed (1.7). The saplings presented 100% of survival in all the treatments. Shade levels did not affect sapling survival, stem diameter, leaf area, chlorophyll a and b, RGR, LR and LAR during the studied intervals. The saplings grown under 50% shadow presented a higher height, larger concentration of total chlorophyll and a lower a/b ratio. Bombacopsis glabra propagates easily, presenting a good development at full sunlight and enduring 30% and 50% shade.
Bombacopsis glabra (Pasq.) A. Robyns; germination; shading; growth
