[" 74.One of the major difficulties in the biological "],[" control of insect/pest is that "],[" 1.The method is less effective as compared "],[" with the use of insecticides "],[" 2.The practical difficulty of introducing the "],[" predator to specific areas "],[" 3.The predator develops a preference to "],[" other deits and may itself become a pest "],[" 4.The predator does not always survive "],[" when transferred to a new environment "]