Aclimatização de Epidendrum viviparum Lindl (Orchidaceae) em substratos provenientes de subprodutos de palmáceas nativas

Abstract

The acclimatization is an important step in the development of plants and can represent a limiting factor in the micropropagation process. The choice of the right substrate is essential to provide good conditions for seedlings development and can also influence the survival rate. This research studied the use of by-products of regional palms in Epidendrum viviparum acclimatization. This species has occurrence in the state of Roraima and their way of life is epiphyte. Seedlings were initially in vitro sown in Bioactive Substances Laboratory of the Graduate Program in Natural Resources of the Federal University of Roraima and after 24 months were grown in Natural Resource Core greenhouse at the Federal University of Roraima, in the municipality of Boa Vista, Roraima. The design was completely randomized with five treatments and twenty-five repetitions, a total of 125 seedlings. The treatments were: T1 - coconut fiber; T2 - tucumã lumps (Astrocaryum vulgare Mart), T3 - patauá pits (Oenocarpus bataua Mart.), T4 - açaí pits (Euterpe oleracea Mart) and T5 - buriti lumps (Mauritia flexuosa L.). The data were submitted to ANOVA and Tukey's test at 5% of probability. The biometric evaluated parameters, at 80 days of ex vitro cultivation, were: shoot height, the longest root length, number of roots, number of leaves, fresh mass and the survival percentage. Regarding the substrates, were analyzed: dry matter, moisture content, mineral material, organic matter, dissolved phosphorus, nitrogen and pH. The substrate consisted of açaí pits provided the highest shoot length and the largest fresh weight of seedlings. The substrate with tucumã pits induced the highest number of leaves and roots, being the most suitable to the Orchidaceae cultivation. Wherein the substrate comprises burity lumps caused the least seedling development of E. viviparum compared with the other studied substrates.