SUBSTRATOS ALTERNATIVOS NA ACLIMATIZAÇÃO DE Phargmipedium sargentianum ROLFE (ORCHIDACEAE)

Abstract

Phragmipedium sargentianum, a terrestrial species, endemic to the Atlantic Forest, a species in the list of endangered species in Brazil. In this study experiments were carried out with a view to seeking a proposal for use of alternative substrates for Sphagnum, in the development of seedlings P. sargentianum during the step of acclimatization. For the acclimatization were used plants from in vitro cultivation, in MS medium supplemented with 20 gL-1 sucrose and 7 gL-1 agar, with two years of age and with approximately 1.9 ± 0.7 cm in length of aerial part. We used six treatments being composed by: T1 sphagnum =; T2 = vermiculite; T3 = sugar cane bagasse carbonized; T4 = sphagnum + vermiculite; T5 = sphagnum + sugar cane bagasse carbonized; T6 = Vermiculite + sugar cane bagasse carbonized, at a ratio of 1:1, totaling six substrates with five replications. The seedlings were transplanted into pots of polypropylene black color. Each repetition received three seedlings. After 47 days we evaluated the survival rate of seedlings, number of leaves and number of roots, height of the aerial part and length of the root system and fresh weight. The data were subjected to analysis of variance and the Tukey test at 5% probability. It can be concluded that the sugar cane bagasse carbonized associated with sphagnum or vermiculite provided the greatest vegetative development in seedlings of orchid P. sargentianum, in the acclimatization stage.