Inclusion of organic components in culture medium to improve the in vitro propagation of Cattleya warscewiczii and Cattleya gaskelliana

Abstract

Worldwide, orchid species are threatened mainly due to human action. For this reason, it is important search for inexpensive in vitro culture media that will help their rapid germination, propagation and conservation. Therefore, this research evaluated the viability, germination and in vitro development of Cattleya gaskelliana and Cattleya warscewiczii using different culture media. Capsules of the orchids were collected, seeds were submitted to different pretreatments (Chlorine 0.5%, Chlorine 1%, distilled water and Sucrose) and seed viability were tested with two concentrations of tetrazolium (0.25% and 0.5%) and two exposure times (24 h and 48 h). Afterwards, the seeds were grown on the following culture media: Murashige and Skoog (MS) basal medium, MS plus 0.5 mg L − 1 of indoleacetic acid (MS+IAA), MS plus 0.5 mg L − 1 of gibberellic acid (MS+GA3), MS supplemented with coconut water (MS+C), MS supplemented with pineapple juice (MS+P) and the commercial medium Orchid Seed Sowing Medium (OSM). Viability for Cattleya gaskelliana was 90.6% in 0.5% tetrazolium, whereas for Cattleya warscewiczii was 90% in 0.25% concentration at 48 h exposure. The most efficient media regarding seedling development of C. gaskelliana and C. warscewiczii during 18 weeks of cultivation were MS+C and MS+P with significant differences (P ≤ 0.05). The use of organic components in the culture media, favors the seeds germination, stimulates the growth and development of C. gaskelliana and C. warscewiczii, contributing in this way, in the decrease of costs generated by plant growth regulators.