ACTIVATED CHARCOAL APPLICATION FOR THE MICROPROPAGATION OF Cattleya crispata (Thunb.) Van den Berg

Abstract

 Micropropagation is an alternative for the genetic conservation and propagation of endemic species from “Campo Rupestre Ferruginoso”, such as the orchid Cattleya crispata. The aim of the present study is to assess the influence of activated charcoal on the in vitro germination, multiplication and elongation phases of C. crispata. Seeds extracted from mature capsules were used for inoculation in the culture medium that was adopted to assess the effect of supplementation, or not, with activated charcoal. Data about germination speed, seedling number, length, vigor, oxidation and contamination (bacterial and/or fungal) were assessed through these phases. Based on the results obtained, the use of activated charcoal was efficient in the in vitro germination and multiplication phases of C. crispata, providing greater speed and percentage of germination, less contamination and oxidation of the tissues, greater number, length and vigor of shoots, being effective for the genetic conservation and production of seedlings of the species. Culture medium without the supplementation of activated charcoal provided the best results for the in vitro elongation, with greater length, vigor and less oxidation of shoots.Aplicação de carvão ativado para micropropagação de Cattleya crispata (Thunb.) Van den Berg  RESUMO: A micropropagação é uma alternativa para a conservação genética e propagação de espécies endêmicas do “Campo Rupestre Ferruginoso”, como a orquídea Cattleya crispata. O objetivo do presente estudo é avaliar a influência do carvão ativado nas fases de germinação, multiplicação e alongamento in vitro de C. crispata. Sementes extraídas de cápsulas maduras foram utilizadas para inoculação no meio de cultura adotado para avaliar o efeito da suplementação, ou não, com carvão ativado. Dados sobre velocidade de germinação, número de brotos por explante, comprimento, vigor, oxidação e contaminação (bacteriana e / ou fúngica) foram avaliados por meio dessas fases. Com base nos resultados obtidos, o uso do carvão ativado foi eficiente nas fases de germinação e multiplicação in vitro de C. crispata, proporcionando maior velocidade e porcentagem de germinação, menor contaminação e oxidação dos tecidos, maior número, comprimento e vigor dos brotos, sendo eficaz para a conservação genética e produção de mudas da espécie. O meio de cultura sem a suplementação de carvão ativado proporcionou os melhores resultados para o alongamento in vitro, com maior comprimento, vigor e menor oxidação dos brotos. Palavras-chave: antioxidante; campos rupestres; orquídea; propagação in vitro.   ABSTRACT: Micropropagation is an alternative for the genetic conservation and propagation of endemic species from rupestrian grasslands, such as the orchid Cattleya crispata. The aim of the present study is to assess the influence of activated charcoal on the in vitro germination, multiplication and elongation phases of C. crispata. Seeds extracted from mature capsules were used for inoculation in the culture medium that was adopted to assess the effect of supplementation, or not, with activated charcoal. Data about germination speed, number of shoots per explant, length, vigor, oxidation and contamination (bacterial and/or fungal) were assessed through these phases. Based on the results obtained, the use of activated charcoal was efficient in the in vitro germination and multiplication phases of C. crispata, providing greater speed and percentage of germination, less contamination and oxidation of the tissues, greater number, length and vigor of shoots, being effective for the genetic conservation and production of plants of the species. Culture medium without the supplementation of activated charcoal provided the best results for the in vitro elongation, with greater length, vigor and less oxidation of shoots. Keywords: antioxidant; orchid; propagation in vitro; rupestrian grasslands