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The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries. Since its first detection in China in late 2017, this pest has been now present in nearly 20 provinces/prefectures in China and is threating tomato and other Solanaceous crops such as potato, eggplants, and tobacco. Here, we provide a timely review on the current distribution, damage, management, and research in China. A standard survey form was designed and 30 answered surveys from 25 provinces have been received. The data showed that the damage has been witnessed in most of the regions despite that the severities vary among the regions. The management is chemical-control biased, and more efforts are needed to increase the adoption of non-chemical alternatives in the Integrated Pest Management packages. An Integrated Pest Management (IPM) package called “CAMEFA” was developed and demonstrated in Yunnan and Xinjiang, the two earliest regions for the invasion. Yet, the adoption by local growers is still limited. Besides T. absoluta, we suggest a multi-pest approach by combing IPM tactics coping with other major insect pests sharing the crop. Lastly, international projects are deemed to serve as a key lever for promoting IPM of T. absoluta and other invasive insect pests.

Cytochrome b5(Cyt-b5) is a small heme protein and known to be involved in a wide range of biochemical transformations, including cytochrome P450 monooxygenase (CYP)-mediated metabolism of endogenous and exogenous compounds. Studies on Cyt-b5are more concentrated in mammals, but are relatively rare in insects. The characteristics and function of Cyt-b5from Locusta migratoriahave not been described yet. We sequenced the full-length cDNA sequence of Cyt-b5from L. migratoria(LmCyt-b5) by reverse transcription-PCR (RT-PCR) based on locust transcriptome database. The phylogenetic analysis showed that LmCyt-b5was closely related to the Cyt-b5from Blattodea. LmCyt-b5was highly expressed in ovary, Malpighian tubules, midgut, gastric caeca, and fat bodies. Silencing of LmCyt-b5had no effect on the susceptibility of L. migratoriato four different insecticides. Suppression of LmCyt-b5or silencing of both LmCyt-b5and LmCPRdid not significantly change the total CYP activity toward the substrate 7-ethoxycoumarin (7-EC). However, coexpression of LmCYP6FD1 with LmCPR and LmCyt-b5together in Sf9 cells by using Bac-to-Bac baculovirus expression system significantly increased the catalytic activity of LmCYP6FD1 toward 7-EC as compared with the coexpression of LmCYP6FD1 with cytochrome P450 reductase (LmCPR) or LmCyt-b5separately. These results suggest that LmCyt-b5plays an important role in the catalytic reaction of LmCYP6FD1 toward 7-EC in our in vitroexperiments. Further study is needed to clarify the role of LmCyt-b5in CYP-mediated catalytic reactions in L. migratoria.