Attraction of Heterorhabditis sp. toward synthetic (E)–ß-caryophyllene,a plant SOS signal emitted by maize on feeding by larvaeof Diabrotica virgifera virgifera

Abstract: Most plants when damaged by herbivore insects, synthesize and release indirectdefense mechanism by release of various chemicals that attract parasitic or predatory insects,which are natural enemies of the herbivores. When attacked by Western corn rootworm, roots ofmany maize plant varieties emit (E)-β-caryophyllene that attracts the neighboringentomopathogenic nematodes to kill the feeding pest. Through plant genetics and biotechnologyit was possible to manipulate this volatile compound in order to increase the effectiveness ofentomopathogenic nematodes in reducing the damage of the pest. In order to further use thisstrategy to improve the effectiveness of Heterorhabditis bacteriophora, we investigate theapplicability of the strategy to be used for genetic selection of enhance host finding and testeddifferent standard laboratory bioassays using three different sand and one agar plate assay.Synthetic (E)-β-caryophyllene and H. megidis (the strain which showed in previous investigation,significant attraction to caryophyllene) were used. In all the bioassays tested no significantdifference were observed between the treatment and control.