Asymbiotic germination, seedling development and plantlet propagation of Encyclia aff. oncidioides - an endangered orchid

Abstract

In order to estimate the best germination conditions of Encyclia aff. oncidioides seeds, five different media (Fast, Knudson C modified by Vajrabhaya, Murashige and Skoog, PB2 and modified Vacin and Went) with different concentrations of plant growth regulators such as benzyladenine (BA), naphthaleneacetic acid (NAA) and gibberellic acid (GA3) were tested. No beneficial effect was observed when BA and NAA were applied to the germination medium and GA₃ inhibited germination. The effect of light, activated charcoal, coconut water and casein hydrolysate on seed germination was also studied. The growth rate of seedlings on three different media supplemented with activated charcoal and plant growth regulators was checked. The applied plant growth regulators had no beneficial effect on the further growth of seedlings. Fast and PB₂ media with 0.2% activated charcoal proved to be the best for E. aff. oncidioides seed germination, seedling development and plantlet propagation.