Disinfestation of orchid seeds is necessary when the germination is performed in vitro. In such case, cultures are supplemented by a source of sugar and salts in order to obtain energy and other requirements. However, the presence of sugar and salts easily allows the development of unwanted microorganisms. To avoid such phenomenon, an efficient procedure must be done as a pretreatment of the seeds with liquid or gaseous substances. In this study with several Brazilian orchids, the seeds were disinfested with sodium hypochlorite solutions containing 0.4% or 0.8% active chlorine for five minutes and sodium hypochlorite or formaldehyde fumes up to two hours, this procedure being efficient for such purpose and making it possible to be used routinely.
orchids; in vitro culture; germination; sodium hypoclorite; formaldehyde