SYNANTHEDON MYOPAFEFORMIS در كنترل لاروهاي پروانه زنبورنماي چوبخوار تنه درختان سيب HETERORHABDITIS BACTERIOPHORA و STEINERNEM كارآيي نماتدهاي بيماري زاي حشرات

An Evaluation of the Efficacy of the Entomopathogenic Nematodes Steinernema sp. and Heterorhabditis Bacteriophora in Controlling Immature Stages of the Apple Clearwing Synanthedon myopaeformis

Control of apple clearwing, Synanthedon myopaeformis Brkh., is of economic importance in apple orchards, West Azabaijan. Application of toxic chemicals to control this pest is considered impractical due to the risk of residues on fruits, the long adult emergence period and the concealed feeding habit of larvae. As an alternative, biological control measures using entomopathogenic nematodes for pest and management have recently gone under more investigation. To evaluate the efficacy of entomopathogenic nematodes in pest control, experiments were carried out at the beginning and the end of the growing season in a heavily infested apple orchard during 1997 and 1998. As inoculum, third stage juveniles of Steinernema sp. and Heterorhabditis bacteriophora were sprayed onto the trunks of infested trees at a concentration of 106 L3 in 300 cm^3 of distilled water. As a result, 63%, 75%, 63% and 69% of the pest larvae were found to be parasitized by Stinernema sp. on April 25th and September 6,h in 1997 and 98, respectively, whereas H. bacteriophora infected 3.3% and 5% of the pest larvae in 1997. Considering the results obtained, it is expected that in case of mass production of effective strains of Steinernema sp., and providing optimal conditions for their activity, this species may be successfully used in integrated management of apple clearwing larvae.