Identification Of Sex Pheromone And Binding Properties Of OBPs From Batocera Horsfieldi (Hope)

Batocera horsfieldi (Hope)(Coleopetra:Cerambycidae) is a stem borer and a major destructive pest damaging various trees. It is difficult to control because of cryptic feeding habit of larve and long life period. Therefore, to be effective, control strategies have to be based on controlling or killing longhorned beetle adults that are exposed to wild to feed and copulate.The subject depends on the prelimimary work by our laboratory. We circumstantial obsevered the mating behavior of B. horsfieldi adults. Isolation and identification the sex pheromone (long range and contact) were performed by some technical means as Y-tube,GC-EAD,GC-MS. Meanwhile, we analyzed the binding properties of one odorant binding protein (OBP) of B. horsfieldi. The major results of this paper list as below:1. The rhythms of B. horfieldi mating behaviorThrough the experiment, we observed the mating behavior of the B. horfieldi adults by video camera. We found that B. horfieldi adults prefer to mating at the three periods (10:00～12:00;16:00～18:00;23:00～01:00;) in one day. The adults mate not too much at early stage of emergence. Mating frequency is significant increase at10days after emergence.The mating frequency peaked at20days later of emergence.2. Isolation and identification of the contact sex pheromone of the B. horfieldiWe used GC-MS to identify the extractive from the surface of B. horfieldi adults. We identified20compounds from the extractive.7compounds like C25,11-Me-C25,2-Me-C26, C27,13-Me-C27,3-Me-C27and9-Me-C29may be the active components.3. Isolation and identification of the volatile sex pheromone of the B. horfieldiWe demonstrated the male adults B. horfieldi have volatile pheromone. The female adults have significant EAG response to one component of the volatile from male adults. It is perhaps the valid component of the volatile pheromone. Through the GC-MS test, we speculate the component has6to8carbon atoms as a straight chain, and contains a hydroxyl or aldehyde group.4. Binding properties of BhorOBP2By competitive binding experiments with1-NPN as a probe, we tested18kinds of volatiles from the host plant of B. horfieldi. BhorOBP2have better binding affinity with trans-2-hexenal2-butylaluminum, salicylaldehyde, verbenone, cis-3-hexyl alcohol, trans-2-hexyl alcohol, β pinene, ethyl acetate (Ki<50).