Analysis of the effect of ultra-low concentrations of benzimidazole on the adaptation of Phalaenopsis amabilis (L.) Blume protocorms

This article presents the results of a study on the effect of ultra-low concentrations of benzimidazole on the morphogenesis of Phalaenopsis amabilis (L.) Blume protocorms under conditions of asymbiotic cultivation. The aim of the work was to evaluate the effectiveness of benzimidazole as a growth stimulator to accelerate protocorm development. Seeds were cultured on «Knudson C» medium with four modification variants: a control medium, a medium with the addition of activated charcoal, a medium with benzimidazole at a concentration of 0,0001 mg/ml, and a medium with a combination of benzimidazole and charcoal. During the 32-week experiment, it was found that the addition of benzimidazole significantly accelerated morphogenesis. The formation of leaves and roots in the experimental variants began 2–4 weeks earlier compared to the control. By the end of the experiment, in the groups with benzimidazole, leaves were formed in over 93% of protocorms, and roots in more than 41%, while in the control group these figures were only 40% and 17%, respectively. The greatest stimulating effect, especially on the development of the root system, was observed with the combined use of benzimidazole and activated charcoal. The obtained data allow us to conclude that benzimidazole in an ultra-low concentration is a highly effective and promising growth stimulator for the clonal micropropagation of orchids, significantly reducing the time required to obtain juvenile plants.