Cultivo in vitro Cattleya violacea Rolfe 1889 (Orchidaceae) utilizando meios de cultura alternativos

Abstract

Cattleya violacea Rolfe (1889) is considered the orchid symbol of Roraima, very appreciated by collectors, orchid growers and producers, that aims to cultivate this species in their collections. The objective of this work is to develop an in vitro cultivation protocol for C. violacea using alternative culture media to the agar and salts and vitamins that make up the traditional medium Knudson C in order to reduce costs for this form of reproduction of orchids . Seedlings used in this study were from in vitro germination of C. violacea estriata with 1.0 cm and 02 leaves. The tested media were composed of agar, vermiculite and charcoal added 60.00 g L-1 pulp regional fruit cupuaçu (Theobroma grandiflorum Schum [Willd. Ex. Spreng]), Buriti (Mauritia flexuosa L.) caja (Spondiaslutea L.), açaí (Euterpe oleracea Mart.), soursop (Annona muricata L.) and murici (Birsonima crassifolia L.) plus 40.0 L-1 ml of coconut water, 2.0 g L -1 activated and 20.0 g L-1 sucrose coal. The pH was adjusted to 5.7 ± 0.1. The experimental design was completely randomized, with 18 treatments and 05 repetitions containing 05 seedlings per bottle. The data were subjected to multivariate analysis of variance (AMOVA) and used the Tukey test at 5% significance level. The biometric parameters evaluated in seedlings after six months of subculture media tested were, shoot height, number of leaves, number of roots, the greater root length and number of shoots. It was observed that the means consisting of agar, and fruit resulted in the highest growth of C. violacea as the seedling shoot height, number of leaves, number of roots, than the traditional means Knudson C. Since the medium composed of agar and Buriti promoted the further development of seedlings and the medium formed by Buriti and vermiculite (BU2), in relation to the shoot number, positively influenced the choice of the best culture medium studied for the subculture of C. violacea.