Differences between volatiles that affect the attraction of different Rosa chinensis (Rosales: Rosaceae) cultivars for Frankliniella intonsa (Thysanoptera: Thripidae)

Abstract

Frankliniella intonsa Trybom is a common flower-inhabiting thrips species and an economically important pest of numerous horticultural and agricultural crops. Olfactory cues are important for thrips to find host plants. In this study, the olfactory behavioral responses of F. intonsa to volatiles from five Rosa chinensis cultivars (Samantha, Zeprti, Queen Elizabeth, Golden Scepter, and Witte Koster) were tested in Y-tube and six-arm olfactometer experiments. Then the volatile components of the R. chinensis flowers were analyzed by SPME coupled with gas chromatography–mass spectrometry (GC–MS). Both female and male thrips showed significant preferences for volatiles from the five R. chinensis cultivars compared with clean air (CA). However, according to the six-arm olfactometer bioassays, female F. intonsa adults were better than male thrips at recognizing the odor stimulation and showed the strongest olfactory preference for Samantha, followed by Zeprti, Queen Elizabeth, Golden Scepter, and then Witte Koster. SPME-GC–MS analysis identified 56, 53, 53, 57, and 60 components in the volatile profiles of Samantha, Zeprti, Queen Elizabeth, Golden Scepter, and Witte Koster, respectively. Eugenol (12.53%) was the most abundant volatile compound in cultivar Witte Koster, ɑ-pinene was the most abundant compound in Samantha (18.26%) and Zeprti (23.73%), and phenylethyl alcohol was the most abundant in Queen Elizabeth (30.10%) and Golden Scepter (31.33%). Therefore, the olfactory responses of F. intonsa to different R. chinensis cultivars demonstrated that host-related volatiles play an important role in thrip host-searching. Future mitigation approaches, for example, attractant traps, could still be used for key monitoring and control of this pest.