Bulblet Formation in Achimenes longiflora

Abstract

The bulblet formation in Achimenes longiflora D.C. cv. Major was investigated under controlled conditions in growth chambers. The bulblet formation in Achimenes longiflora cuttings was found to be inhibited by long‐day treatment such as continuous illumination. The degree of inhibition depended, however, on the quality of the light. High intensity far red and especially infrared emission was needed to effectively suppress the bulbing. As opposed to this, red light was found to be stimulatory. When red light (660 nm) was substituted for 20% of the white light, the bulbing was promoted over 400%.Gibberellic acid was totally inhibitory in all cases. The cytokinins benzyladenine and 6‐γ,γ‐dimethylallylaminopurine were strongly promotive and even inductive under inhibitory light conditions. The growth inhibitor N‐dimethylamino succinamic acid also stimulated bulblet formation. α‐Naphthyl‐acetic acid was strongly inhibitory, an effect which could not be overcome by benzyladenine.