The effect of hypo- and hyperthermia on the infection of potato by Clavibacter michiganensis subsp. sepedonicus

The influence of ring rot pathogen Clavibacter michiganensis subsp. sepedonicus (Cms) on activity of weak-associated with wall cell peroxidase of cell suspension cultures of two potato (Soianum tuberosum L.) cultivars which are differs in resistance to this pathogen during hypo-and hyperthermia. In low resistant cultivar temperature changes did not caused changes in weak-associated with wall cell peroxidase activity. Pathogen influence did not cause changes in its activity in these conditions too. At the same time pathogen actively grew under low temperature conditions, but at 38°C the increase of bacterial cell number was detected only during the first five days of experiment, but after this date bacterial cell began perishes. In resistant cultivar temperature increase caused some increase of peroxidase activity. Temperature decrease caused the decrease of peroxidase activity, but following pathogen addition caused increase of weak-associated with wall cell peroxidase activity. In high temperature conditions pathogen addition caused significant increase of peroxidase activity during the first minutes after pathogen addition (because of changes in peroxidase molecule activity) and after 1.5-2 h of incubation (because of changes in genome expression and peroxidase synthesis). The data obtained allows us to conclude that if potatoes are putting in cold soil it could promote potato contamination by ring rot.