obligate pathogen meaning in Hindi

Study of obligate pathogens is difficult because they cannot usually be reproduced outside the host.
"Ascosphaera aggregate " is an obligate pathogen with a preference for bees belonging to the family Megachilidae.
It is an obligate pathogen with cladoceran crustaceans from the " Daphnia " genus serving as its hosts.
It is best known by its representative " Pandora neoaphidis ", which acts as an obligate pathogen in various species of aphids.