Some factors affecting the spread of mycoplasma in plants

Studying the spread of mycoplasma, the causal agent of potato witches' broom disease, in tomato plants after grafting with infectious grafts ofNicotiana glauca Grah., we found that after 9 days of graft symbiosis a hundred per cent infection occurred, whereas with infectious grafts ofSolanum lycopersicum this took place after 16 days. The first symptoms of the disease were manifested on tomato plants 21 days after grafting with infectiousNicotiana glauca grafts and 28 days after grafting with infectious tomato grafts. The results obtained present evidence for the possible preference of tomato plants for mycoplasma.