Espécies potenciais para plantio em área antropizada na região central do Rio Grande do Sul

Abstract

The success of forest plantations, both for restoration and commercial purposes, is directly related to the production process of seedlings in the nursery and to the cultural treatments used after planting. Thus, the objective of this study was to verify the survival and initial growth of Casearia sylvestris, Handroanthus heptaphyllus, Inga vera, Parapiptadenia rigida and Schinus terebinthifolius seedlings in anthropized area, according to container used in nursery seedlings production and use of mulching on planting. The experiment was conducted in a factorial scheme (2x2), considering the types of containers used in the production of the seedlings (plastic bag and tube) and the presence or absence of mulching around the planting seedlings. The planting occurred in October 2013, in a randomized block design, with five replications. At 24 months after planting the survival of the seedlings was verified, besides the morphological and physiological attributes. As for survival on the field, only I. vera presented a difference between treatments, with a higher value for seedlings produced in a plastic bag (86.67%). The other species obtained similar averages among the treatments, presenting rates of 72.5; 85.0; 80.01 and 81.7%, respectively, for the seedlings of C. sylvestris, H. heptaphyllus, P. rigida and S. terebinthifolius. There was a positive effect of the use of plastic bag for the attributes increase in height (IncH) and in stem diameter (IncDC), crown area (AC) and shoot dry mass (MSPA) for C. sylvestris , H. heptaphyllus and Inga vera. For P. rigida, the use of the plastic bag was superior in AC and MSPA and for seedlings of S. terebinthifolius, only in IncH. The presence of mulching at the planting favored the attributes IncH, IncDC, AC and MSPA of H. heptaphyllus, as well as AC and MSPA of C. sylvestris, however, was unfavorable to IncH of P. rigida seedlings. For I. vera and S. terebinthifolius, the use of mulching was not effective in aiding the growth of both species. Regarding the physiological parameters, no difference was observed between the treatments tested, independent of the specie, possibly due to its adaptation to the planting area. Thus, the morphological attributes indicate that seedlings of C. sylvestris, H. heptaphyllus, I. vera and P. rigida produced in a 1.5 L plastic bag container present high survival, higher growth and area coverage. On the other hand, seedlings of S. terebinthifolius can be produced in 180 cm³ tube type containers, when destined to plantations of restoration in anthropized area. Mulching as a cultural treatment should be applied in the planting of C. sylvestris and H. heptaphyllus to favor its growth in the field, however, for the other species the use of this cultural tract should be investigated in future studies, being tested more quantity/volume of coverage, not only in the surroundings, but throughout the planting area.