The codling moth Cydia pomonella, a major invasive pest of pome fruit, has spread around the globe in the last half century. We generated a chromosome-level scaffold assembly including the Z chromosome and a portion of the W chromosome. This assembly reveals the duplication of an olfactory receptor gene (OR3), which we demonstrate enhances the ability of C. pomonella to exploit kairomones and pheromones in locating both host plants and mates. Genome-wide association studies contrasting insecticide-resistant and susceptible strains identify hundreds of single nucleotide polymorphisms (SNPs) potentially associated with insecticide resistance, including three SNPs found in the promoter of CYP6B2. RNAi knockdown of CYP6B2 increases C. pomonella sensitivity to two insecticides, deltamethrin and azinphos methyl. The high-quality genome assembly of C. pomonella informs the genetic basis of its invasiveness, suggesting the codling moth has distinctive capabilities and adaptive potential that may explain its worldwide expansion.

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Eupatorium adenophorum is one of the more noxious invasive plants worldwide. However, the mechanisms underlying its invasiveness are still not well elucidated. In this study, we compared the invader with its two native congeners (E. heterophyllum and E. japonicum) at four irradiances in terms of growth, biomass allocation, morphology, and photosynthesis. The higher light-saturated photosynthetic rate (P max ) and total leaf area of the invader may contribute to its higher relative growth rate (RGR) and total biomass compared with its native congeners. Total biomass and RGR increased significantly with the increase of P max and total leaf area. The higher support organ mass fraction and the lower root mass fraction of the invader may also contribute to its higher RGR and biomass through increasing carbon assimilation and reducing respiratory carbon loss, respectively. The higher growth rate of the invader increased its total leaf area, ramet number, and crown area. These traits may help the invader to form dense monoculture, outshading native plant species. However, consistently higher leaf area ratio, specific leaf area, and leaf mass fraction were not found across irradiances for the invader compared with its native congeners. Higher plasticity in response to irradiance was also not found for the invader. The invader retained advantages over the natives across irradiances, while its performance decreased with lower irradiance. The results indicate that the invader may be one of the few super invaders. Reducing irradiance may inhibit its invasions.

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Diglyphus species are dominant biocontrol agents for suppressing outbreaks of agromyzid leafminers in fields. In July 2015, we collected a new thelytokous species of Diglyphus in Qinghai, China. The wasp is here named as D. wani Liu, Zhu & Yefremova sp. nov., based on morphological and molecular analyses. The life history and biocontrol potential of the wasp were studied in the laboratory and by providing Liriomyza sativae larvae. The intrinsic rate of increase, finite rate of increase, and mean generation time were 0.2373 d−1, 1.2678 d−1, and 15.9 d, respectively. The wasps showed three types of host-killing behaviour, namely parasitism, host feeding and host stinging, resulting in 47.6, 94.4 and 3.4 host larvae killed per wasp over a lifetime, respectively. The finite total host-killing rate was 1.0071 and the wasp showed strong synovigeny. The wasp may be a crucial biocontrol agent against agromyzid leafminers.