Vitreous state in vitro culture: ethylene versus cytokinin.

The occurrence of a developmental anomaly i in vitro culture, named "vitreous plant", has been shown to be a deficiency in lignification. Several causes have been proposed, most recently the physical state of the culture medium and ethylene. Experiments, conducted to verify these suggestions, led toresults that did not confirm either the physical state or ethylene as causal agents. It rather appeared that cytokinins did induce the anomaly, probably by excessively promoting cell-divisions at the expense of cell-differentiation.