Growth and infectivity of callus cultures of tomato plants infected with a mycoplasma disease — Potato witches' broom

Abstract

Callus tissues were derived from the stem of healthy tomato plants (Lycopersicum esculentum Mill. ev. Průhonické) and of plants infected with potato witches' broom—a disease caused by mycoplasma. Callus cultures were established on modified fully synthetic media described byMorel (1948) and byMurashige andSkoog (1962). Callus cultures obtained from diseased plants were grown and subcultured on both media, growth in primary isolates from healthy plants took place on the Murashige and Skoog medium only. Growth of callus tissue derived from diseased plants was more vigorous even after several subcultivations in comparison with callus tissues isolated from healthy plants. Variations in the morphology in these callus cultures were not noted. Callus cells of diseased plants varied in size; they were about 50% larger than those from healthy ones. Implantation of primary and subcultivated callus tissues into tomato stems of healthy plants did not show any symptoms of infection on test plants.