Behavioral preference of dark black chafer, Holotrichia parallela (Coleoptera: Scarabaeidea) adults to volatiles of pear plant

In order to clarify the correlation between the behavioral preference of Holotrichia parallela adults and plant volatiles of pear plant, and to analyze the olfactory behavioral preference of the adults. Based on the result H. parallela adults preferred to feeding and mating towards pear in the ecosystem of pear + walnut + castor + sweetpotato in the previous studies. Gas chromatography-mass spectrometry (GC-MS) was used to analyze volatiles in pear plants. Gas chromatography-electroantennogram (GC-EAD) was used to evaluate the electrophysiological responses of the antennae of H. parallela to pear plant volatiles. The preferences of H. parallela adults to different volatiles were assessed in the binary-choice tube and artificial cage. The results showed that main compounds of the volatiles in pear plants were (E)-β-ocimene, (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), (Z)-3-hexenyl acetate, 2-ethyl-1-hexanol, linalool and α-farnesene. The antennae of male and female adult of H. parallela generated strong potential reactions to pear plant volatiles (E)-β-ocimene, DMNT, 2-ethyl-1-hexanol, and α-farnesene, and weak potential reactions to Linalool and (Z)-3-hexenyl acetate. The female of H. parallela exhibited significant preference tendency to (E)-β-ocimene and α-farnesene while the male showed the significant preference tendency to (E)-β-ocimene, 2-ethyl-1-hexanol and α-farnesene. These research findings provide a theoretical basis for the effective control of H. parallela adult using attractants.