Abstract
Despite the importance of fungi as natural regulators ofmany insect pests, only afew have been developed as bioinsecticides and used on an operational scale. Entomopathogenic fungi are ojien still considered as 100 dependent on environmental factors. Therefore one of the greatest challenges for improving fungi as microbial control agents is to identify and establish a hierarchy of pertinent environmental constraints and to develop ways to overcome them. Environmental conditions prevailing in the habitats of the targeted pest populations need to be analyzed so that well-adapted isolates can be selected