Vegetative development of <em>Brassocattleya pastoral </em>‘Rosa’ and <em>Miltonia regnelli</em> Rchb.f. X <em>Oncidium crispum </em>L. (Orchidaceae) in substrates alternative to xaxim (tree fern fiber)

Abstract

The objective of this work was to evaluate substrates to be used in stead of xaxim (tree fern fiber) for the cultivation of two orchid hybrids, namely Brassocattleya pastoral 'Rosa' and Miltonia regnelli Rchb.f. x Oncidium crispum Lodd. The following treatments were evaluated: T₁ de-fibered xaxim, T₂ coconut fiber, T₃ Pinus husk + coconut fiber, T₄ carbonized rice husk + coconut fiber, T₅ coconut fiber + vegetal coal, T₆ carbonized rice husk and T₇ Pinus husk + coconut fiber + plant coal. Substrates mixes were in equal volume proportions The following parameters were evaluated: total fresh mass, aerial part height, number of pseudobulbs, number of buds, number of flowers, root volume; remaining substrate volume, hydrogen ion potential and electric conductivity. The experiment was set according to a completely random design with ten replications per treatment. The resulting means were com­pared by the Tukey’s test at the 5% level of probability. Carbonized rice showed the best results as an alternative substrate to tree fern fiber for Brassocattleya pastoral 'Rosa' and Miltonia regnelli x Oncidium crispum development.

Additional keywords: Orchidaceae; Dicksonia sellowiana; carbonized rice husk; coconut fiber; Pinus husk.