【Aim】 The oviposition deterrence of herbivore-induced plant volatiles (HIPVs) from cotton plants damaged by the larvae of the turnip moth, Agrotis segetum, was evaluated on conspecific females, and the composition and functions of the major HIPVs were characterized in this study in order to identify the active components attracting or deterring adult oviposition.【Methods】 We identified HIPVs from cotton plants damaged by A. segetum larvae using a gas chromatography-mass spectrometer (GC-MS) and evaluated the electrophysiological activity and oviposition deterrent bioactivity of the major HIPVs to female adults of A. segetum using the electroantennogram (EAG) and oviposition cage bioassay method, respectively.【Results】 The female adults of A. segetum preferred to lay eggs on the healthy cotton plants over the damaged cotton plants, and the number of eggs laid on the healthy cotton plants was 6.59 times as high as that on the damaged cotton plants by A. segetum larvae. The HIPVs emitted from the cotton pants damaged by A. segetum larvae mainly consisted of benzaldehyde, linalool, β-caryophyllene, humulene, tetradecane, hexadecane, etc. Among them, benzaldehyde and linalool elicited strong EAG responses on the female antennae, showing a dose-response pattern. In the oviposition cage bioassay, linalool significantly deterred oviposition of female adults of A. segetum, while benzaldehyde attracted female adults to oviposit. 【Conclusion】 HIPVs emitted from cotton plants damaged by A. segetum larvae significantly deter oviposition of conspecific females, and linalool is considered as a potential oviposition deterrent.

 【Aim】 In the previous study, we found that both Artemisia argyi and Torilis scabra have attractive or repellent effects on insects. However, there are no reports on the effects of A. argyi and T. scabra and their volatiles on Bemisia tabaci MED adults. Therefore, this study aims to test whether A. argyi and T. scabra and their volatiles could be used for green prevention and control of B. tabaci MED adults. 【Methods】 The preference of B. tabaci MED adults to four plants including Solanum lycopersicum, A. argyi, T. scabra and Cucumis sativus and olfactory responses of B. tabaci MED adults to A. argyi and T. scabra were detected by four-arm olfactometer and Y-tube olfactometer, respectively, and the components and relative contents of volatiles in A. argyi and T. scabra leaves were identified and analyzed by GC-MS. Finally, the olfactory responses of B. tabaci MED adults to the main volatiles of A. argyi and T. scabra leaves were detected by Y-tube olfactometer. 【Results】 The numbers of B. tabaci MED adults referring to S. lycopersicum and C. sativus (22 and 21, respectively) were significantly higher than those to A. argyi and T. scabra (16 and 9, respectively). Further determination of the selectivity of B. tabaci MED adults to A. argyi and T. scabra showed that the number of B. tabaci MED adults preferring to A. argyi (60) was extremely significantly higher than that to the blank control (22), while the number of B. tabaci MED adults preferring to T. scabra (22) was extremely significantly lower than that to the blank control (55). GC-MS analysis showed that the α-copaene content in A. argyi leaves was the highest, and the cyclohexene content in T. scabra leaves was the highest. Olfactory response tests indicated that the number of B. tabaci MED adults preferring to α-copaene (1 μg/L)(60) was extremely significantly higher than that to the blank control (24), and the number of B. tabaci MED adults preferring to cyclohexene (1 μg/L)(20) was extremely significantly lower than that to the blank control (62). 【Conclusion】 The volatiles of A. argyi leaves show strong attraction to B. tabaci MED adults, and the volatiles of T. scabra leaves show strong repellency to B. tabaci MED adults. Therefore, the volatiles of A. argyi and T. scabra leaves can be used as food attractant or repellent to control B. tabaci MED adults effectively.

 Confronted with herbivores, plants have evolved a sophisticated network of defense, which can be classified as constitutive and induced. After perceiving herbivore-derived molecular via receptors, the tea plant (Camellia sinensis) will initiate early signaling events, and then activate multiple signaling pathways of plant pheromones, such as jasmonic acid (JA), salicylic acid (SA), ethylene (ET), gibberellin and other phytohormones, resulting in the accumulation of secondary metabolites, and eventually induce direct and indirect resistances to pests. Based on the recent research progress in tea plant defense responses induced by main insect pests and their regulatory mechanisms, we summarized the components and ecological functions of herbivore-induced plant volatiles (HIPVs) of the tea plant, and their application in green pest control, uncovered the important defense signaling network involved in the regulation of insect-induced resistance in the tea plant, emphasized on the research progress of the JA pathway in the tea plant, and proposed suggestions for future research. The infestation of Ectropis obliqua, Matsumurasca onukii and Myllocerinus aurolineatus induces 17 shared volatiles from tea plants, but induces eight, three and two specific volatiles from tea plants, respectively. Among the above volatiles, five, one and six volatiles were found to have attractiveness to E. obliqua, M. onukii and M. aurolineatus, respectively, while two volatiles and one volatile are involved in the repellence against E. obliqua and M. onukii, respectively. Thus, the attractants to these three insect species and the repellents against M. onukii have been screened out. The JA pathway and SA pathway are the two main pathways involved in the defense responses in tea plants to multiple insect pests, and the JA pathway plays a vital role. Meanwhile, several plant hormones, including auxin, abscisic acid, gibberellin, etc., also take part in tea plant induced defense processes. So far, many genes associated with JA biosynthesis and regulation have been cloned and characterized. Based on the understanding of their functions in tea plant resistance against insects, the fact that JA pathway positively regulates direct or indirect tea plant resistance to insects was revealed. We suggest that the further study should focus on further clarifying the molecular mechanisms of insect-induced resistance in the tea plant, and the utilization of induced defense against insect pests in tea plants. This article will provide guidance for in-depth research on the molecular mechanisms in induced resistance in the tea plant and further development of green pest prevention and control technologies.