Central Potato Research Institute, Shimla, 171 001, (HP).
Wilt causing bacterium Ralstonia solanacearum had recently been reported to produce unstable nonmucoid phenotype. In host plant it produces nonmucoid and mucoid types and multiply as fast as wild types. However there was no selective population build up of mucoid type in vivo and the proportion of nonmucoid phenotype always exceeded over mucoid types.