Shubham Srivastav, Kamala Jayanthi Pagadala Damodaram, Sumathi Manoharan, Arul Dhayalan, Naresh Ponnam, Vasugi Chinnaiyan, Sridhar Vaddi, Selvakumar Govindan, Rachana Rajan Remani, Ganesan Sangeetha, Prabhudev Magala Veerabhadraswamy, Jessa Joseph, Rajeshwaran Balakumar
Linalool is a promising attractant semiochemical for T. parvispinus, with potential application in semiochemical-based integrated pest management strategies, subject to validation under open-field conditions for sustainable pest control. © 2026 Society of Chemical Industry.
BACKGROUND: The southeast Asian thrips, Thrips parvispinus (Karny), is an invasive and economically important pest that has recently emerged as a major threat to chilli cultivation in India. Adults preferentially colonize flowers and the undersides of leaves, causing severe damage through feeding and oviposition. The initial report of T. parvispinus in India from papaya (Carica papaya L.) flowers suggested that floral volatile cues may play an important role in host location.
RESULTS: This study investigated the behavioural responses of adult T. parvispinus to volatile organic compounds (VOCs) emitted by chilli foliage, chilli flowers, and papaya flowers using a four-arm olfactometer. Behaviourally active volatiles were identified through coupled gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). Olfactometer assays showed that T. parvispinus was significantly attracted to both chilli and papaya floral volatiles, with floral odours eliciting stronger attraction than chilli foliage. Among the electrophysiologically active compounds, linalool was identified as the most potent attractant. In dual-choice assays, linalool elicited significantly greater attraction than chilli floral volatiles (P < 0.0001) and papaya floral volatiles (P = 0.0002). At 100 ppm, linalool induced significant attraction (P = 0.0002), while dose-response assays (1-1000 ppm) demonstrated significant attraction at 1, 25, 50, and 75 ppm (P = 0.02-0.04). Molecular docking further revealed moderate-to-strong binding affinities of linalool with all tested odourant-binding proteins (OBPs, -4.3 to -5.5 kcal mol-1), with the strongest interaction observed for OBP6.
CONCLUSION: Linalool is a promising attractant semiochemical for T. parvispinus, with potential application in semiochemical-based integrated pest management strategies, subject to validation under open-field conditions for sustainable pest control. © 2026 Society of Chemical Industry.