الفهرس | Only 14 pages are availabe for public view |
Abstract The present work was conducted in the Experimental Farm, Faculty of Agriculture, Mansoura University, aiming to survey insect natural enemies agents which associated with I. seychellarum (on ficus and coral trees), M. hirsutus (on hibiscus plants) and S. sacchari (on sugarcane plants in Dikernes district). Also, to estimate the role of such natural enemies in managing these pests. Also, some laboratory experiments were carried out to investigate the pathogenicity of isolated entomopathogens and to evaluate the searching behavior of the main predators in response to host plant species. The obtained results could be summarized as follow : 1) The coccidiphagus predator, C. montrouzieri approved to be the main mortality factor on S. sacchari and M. hirsutus populations. It was the most abundant predator and showed a tendency to aggregate where its prey density is high. 2) The high population level (predator / prey ratio) and the aggregation behavior of R. cardinalis suggested that this species is an important bioagent against the margarodid, I. seychellarum on ficus, guava and kaki trees. 3) Olfactory stimulants produced by the host plant may play a role in host recognition and predator activity (killing power). 4) The entomopathogenic bacteria, Bacillus sp., Streptomyces sp. and Micrococcus sp. promise to be a good bioagents against I. seychellarum. 5) The bacterial control agents can be integrated with the predator, R. cardinalis in IPM program for I. seychellarum. 6) The fungal pathogen, A. flavus exhibited high activity as a mortality factor against S. sacchari. |