The term ble but not cultivable is used for -
It has not been possible to culture Mycobacterium leprae in vitro so far. Can be grown in the footpad of the mouse. It is a long and strenuous process and therefore considered noncultivable REF:Textbook of Microbiology, Ananthanarayan, and Paniker. Page no.: 346, 364
M. leprae
M. tuberclosis
Treponema pallidum
Salmonella
general microbiology