Identification and characterization of volatile attractants for the flower thrips, (Frankliniella intonsa), from the host Hemerocallis citrina

Introduction Flower thrips ( Frankliniella intonsa Trybom) is a widespread pest threatening vegetables globally, with severe infestations in daylily ( Hemerocallis citrina Baroni) planting regions in China. Methods Volatile compounds from H. citrina at leafing, bolting, and flowering stages were identified via gas chromatography-mass spectrometry (GC-MS). Behavioral assays using a Y-tube olfactometer and field trapping experiments were conducted to evaluate the attractiveness of key volatiles. Results A total of 60 volatile compounds were detected, with aromatic compounds (especially sesquiterpenes) prominent during peak thrip infestations. E-β-farnesene, nerol, and linalool attracted thrips at 100 mg/mL and 10 mg/mL in behavioral assays. Field tests showed nerol (160.0 ± 98.6 thrips/trap) and a mixed-component lure (182.5 ± 83.7 thrips/trap) had superior attractiveness; yellow sticky cards outperformed other colors. The three active components synergistically increased thrip capture on all card types. Discussion These findings provide a theoretical foundation for environmentally friendly control strategies of flower thrips using host plant volatiles.