First report of Heterorhabditis bacteriophora (Poinar, 1975) (Nematoda: Heterorhabditidae) isolated from the red palm weevil Rhynchophorus ferrugineus (Oliver, 1790) (Coleoptera: Curculionidae) in Turkey

摘要

Infestation levels of the red palm weevil, Rhynchophorus ferrugineus (Oliver, 1790) and its natural enemies on palm trees in recreation areas were investigated in the Adana province of Turkey in 2008. The trunks of dead palms were sampled for R. ferrugineus and for the presence of entomo-pathogenic nematodes. While 20% of Phoenix canariensis Hort. were found to be killed by R. ferrugineus, only 2 trees from other species, 1 Washingtonia filifera (L. Linden) and 1 Phoenix dactlylifera L., were killed.Only one species of entomopathogenic nematode, Heterorhabditis bacteriophora (Poinar, 1975) (Nematoda: Heterorhabditidae), was isolated from the R. ferrugineus specimens. Seasonal mortality rate in the total larval population (total 565 larval specimens) of R. ferrugineus was 69%. H. bacteriophora resulted in a significant mortality rate (80%) in the pupae population (total 314 pupal specimens). Overall, 70% of the total of 879 pre-adult specimens were found to be fatally infested by the attacks of this nematode. Heterorhabditis bacteriophora killed few adults, corresponding to 2% of the overall mortality rate. It is concluded that H. bacteriophora could be evaluated as a potential candidate for biological control of R. ferrugineus in the Mediterranean region.