This work was carried out with the aim of studying the effect of pulp of fruits on the growth of orchids seedlings in vitro. Three species of epiphytic brazilian orchids were used: Laelia longipes Rchb.f., Laelia tenebrosa Rolfe e Miltonia spectabilis (Lindley). The following nutritive media were tested: 10:10:10 (N:P:K), at 1 gL-1, 10:30:20 at 1 gL-1, apple pulp, at 10 gL-1, tomato pulp at 10 gL-1, banana pulp at 50 gL-1, and also the KNUDSON, VACIN and WENT, MURASHIGE and SKOOG (MS) media. In seedlings of L. Longipes cultivated in 10:10:10 and banana pulp was observed higher accumulation, and the lowest one in MS. Analysis of dry mass results for Miltonia spectabilis showed that the media 10:30:20 and banana pulp propiciated the highest dry mass accumulation and the MS medium, the lowest. In decreasing order of total dry mass accumulation are the media 10:30:20 and banana pulp, followed by 10:10:10, tomato pulp, KNUDSON (58,3%), VACIN e WENT (18,7%), apple pulp (13,2%) and MS (4,1%). For Laelia tenebrosa, seedlings cultivated in banana pulp incorporated higher dry mass content, followed by those cultivated in 10:10:10, whereas the remaining media propitiated reduced accumulation.
orchids micropropagation; nutritive media; in vitro nutrition