Phytoplasma detection in rose shoots propagated in vitro

The results of PCR examination indicated that during two years of tissue culture at standard conditions, on the medium with BAP 1 mg l-1 and continuous temperature of 20oC, phytoplasma could be detected in diseased plants of rose cv Sacha and Jazz. In the second year of micropropagation phytoplasma detection rate in tissues of infected roses increased and was relatively higher than in the first one. To test whether phytoplasmas are sensitive to temperature and light intensity, phytoplasma-affected micropropagated rose plants were grown on medium with BAP 1.0 or 0.5 mg l-1 and at the temperature of 4, 15, 20 or 25oC in darkness or in the light. PCR analysis indicated that phytoplasma detection was not effected by these conditions during 4 weeks of culturing. However, phytoplasma was not detectable in rose plants after 8 weeks culturing on the same medium without transplanting. Micropropagated rose shoots maintained on medium with Gentamycin or Baytril at the concentration of 25.0 or 50.0 mg l-1 had reduced growth and were chlorotic. However, no direct effect of applied antibiotics on phytoplasma detection was evidenced.