Drosophila suzukii and Tuta absoluta are successful biological invaders of agroecosystems. Their integrated pest management (IPM) programs involve the release and/or conservation of natural enemies. Among these, Ganaspis kimorum is a major Asian parasitoid of D. suzukii and has been introduced as a classical biological control agent of this pest in Europe and North America, while Necremnus tutae is a key fortuitous parasitoid of T. absoluta in the Mediterranean region. Bioinsecticides represent key alternatives to chemicals for controlling both pests. This study investigated the potential compatibility of both parasitoids with Beauveria bassiana, Bacillus thuringiensis, garlic essential oil (EO), and spinosad, in comparison to two synthetic insecticides, cyantraniliprole and chlorantraniliprole. The results showed that combining each of the tested insecticides with G. kimorum slightly increased pest mortality compared to the insecticide alone. Necremnus tutae had a significant additive effect on host mortality when combined with insecticides. Beauveria bassiana and B. thuringiensis were most compatible with both parasitoid species. Both garlic EO and chlorantraniliprole impaired the survival of immature N. tutae and showed sublethal toxicity on the reproductive and non-reproductive behaviors of N. tutae. Spinosad exhibited high acute toxicity on both juvenile and adult parasitoids of both species. Overall, these findings provide useful insights into insecticide selectivity toward two key parasitoids and offer new knowledge on the potential of combining natural enemies and bioinsecticides for optimized IPM.

Biological invasions threaten global biodiversity, altering landscapes, ecosystems, and mutualistic relationships like pollination. Orchids are one of the most threatened plant families, yet the impact of invasive bees on their reproduction remains poorly understood. We conduct a global literature survey on the incidence of invasive honeybees (Apis mellifera) on orchid pollination, followed by a study case on Australian orchids. Our literature survey shows that Apis mellifera is the primary alien bee visiting orchids worldwide. However, in most cases, introduced honeybees do not deposit orchid pollen. We also test the extent to which introduced honeybees affect orchid pollination using Diuris brumalis and D. magnifica. Diuris brumalis shows higher fruit set and pollination in habitats with both native and invasive bees compared to habitats with only introduced bees. Male and female reproductive success in D. magnifica increases with native bee abundance, while conversely pollinator efficiency decreases with honeybee abundance and rises with habitat size. Our results suggest that introduced honeybees are likely involved in pollen removal but do not effectively deposit orchid pollen, acting as pollen wasters. However, Apis mellifera may still contribute to pollination of Diuris where native bees no longer exist. Given the global occurrence of introduced honeybees, we warn that certain orchids may suffer from pollen depletion by these invaders, especially in altered habitats with compromised pollination communities.

The origin of the German cockroach, Blattella germanica, is enigmatic, in part because it is ubiquitous worldwide in human-built structures but absent from any natural habitats. The first historical records of this species are from ca. 250 years ago (ya) from central Europe (hence its name). However, recent research suggests that the center of diversity of the genus is Asian, where its closest relatives are found. To solve this paradox, we sampled genome-wide markers of 281 cockroaches from 17 countries across six continents. We confirm that B. germanica evolved from the Asian cockroach Blattella asahinai approximately 2,100 ya, probably by adapting to human settlements in India or Myanmar. Our genomic analyses reconstructed two primary global spread routes, one older, westward route to the Middle East coinciding with various Islamic dynasties (~1,200 ya), and another younger eastward route coinciding with the European colonial period (~390 ya). While Europe was not central to the early domestication and spread of the German cockroach, European advances in long-distance transportation and temperature-controlled housing were likely important for the more recent global spread, increasing chances of successful dispersal to and establishment in new regions. The global genetic structure of German cockroaches further supports our model, as it generally aligns with geopolitical boundaries, suggesting regional bridgehead populations established following the advent of international commerce.

Biogeochemical processes mediated by plants and soil in coastal marshes are vulnerable to environmental changes and biological invasion. In particular, tidal inundation and salinity stress will intensify under future rising sea level scenarios. In this study, the interactive effects of flooding regimes (non-waterlogging vs. waterlogging) and salinity (0, 5, 15, and 30 parts per thousand (ppt)) on photosynthetic carbon allocation in plant, rhizodeposition, and microbial communities in native (Phragmites australis) and invasive (Spartina alterniflora) marshes were investigated using mesocosm experiments and 13CO2 pulse-labeling techniques. The results showed that waterlogging and elevated salinity treatments decreased specific root allocation (SRA) of 13C, rhizodeposition allocation (RA) 13C, soil 13C content, grouped microbial PLFAs, and the fungal 13C proportion relative to total PLFAs-13C. The lowest SRA, RA, and fungal 13C proportion occurred under the combined waterlogging and high (30 ppt) salinity treatments. Relative to S. alterniflora, P. australis displayed greater sensitivity to hydrological changes, with a greater reduction in rhizodeposition, soil 13C content, and fungal PLFAs. S. alterniflora showed an earlier peak SRA but a lower root/shoot 13C ratio than P. australis. This suggests that S. alterniflora may transfer more photosynthetic carbon to the shoot and rhizosphere to facilitate invasion under stress. Waterlogging and high salinity treatments shifted C allocation towards bacteria over fungi for both plant species, with a higher allocation shift in S. alterniflora soil, revealing the species-specific microbial response to hydrological stresses. Potential shifts towards less efficient bacterial pathways might result in accelerated carbon loss. Over the study period, salinity was the primary driver for both species, explaining 33.2-50.8 % of 13C allocation in the plant-soil-microbe system. We propose that future carbon dynamics in coastal salt marshes under sea-level rise conditions depend on species-specific adaptive strategies and carbon allocation patterns of native and invasive plant-soil systems.

The introduction and subsequent range expansion of the American bullfrog (Lithobates catesbeianus) is part of a rising trend of troublesome biological invasions happening in China. This detrimental amphibious invasive species has strong adaptability. After its introduction and spread, it established its own ecological niche in many provinces of China, and its range has continued to expand to more areas. Previous studies recorded the introduction time of bullfrogs and calculated the changes in their genetic diversity in China using mitochondria, but the specific introduction route in China is still unknown. Expanding upon previous research, we employed whole-genome scans (utilizing 2b-RAD genomic sequencing) to examine single nucleotide polymorphisms (SNPs) and microsatellites within Lithobates catesbeianus to screen the genomes of these invasive amphibian species from eight Chinese provinces and two U.S. states, including Kansas, where bullfrogs originate. A total of 1,336,475 single nucleotide polymorphic loci and 17 microsatellite loci were used to calculate the genetic diversity of bullfrogs and their migration pathways. Our results suggest that the population in Hunan was the first to be introduced and to spread, and there may have been multiple introductions of subpopulations. Additionally, the genetic diversity of both the SNP and microsatellite loci in the Chinese bullfrog population was lower than that of the US population due to bottleneck effects, but the bullfrogs can adapt and spread rapidly. This study will offer crucial insights for preventing and controlling future introductions into the natural habitats in China. Additionally, it will assist in devising more precise strategies to manage the existing populations and curtail their continued expansion, as well as aim to improve clarity and originality while mitigating plagiarism risk.

Reptiles are an important, yet often understudied, taxon in nature conservation. They play a significant role in ecosystems1 and can serve as indicators of environmental health, often responding more rapidly to human pressures than other vertebrate groups.2 At least 21% of reptiles are currently assessed as threatened with extinction by the IUCN.3 However, due to the lack of comprehensive global assessments until recently, they have been omitted from spatial studies addressing conservation or spatial prioritization (e.g., Rosauer et al.,4,5,6,7,8 Fritz and Rahbek,4,5,6,7,8 Farooq et al.,4,5,6,7,8 Meyer et al., 4,5,6,7,8 and Farooq et al.4,5,6,7,8). One important knowledge gap in conservation is the lack of spatially explicit information on the main threats to biodiversity,9 which significantly hampers our ability to respond effectively to the current biodiversity crisis.10,11 In this study, we calculate the probability of a reptile species in a specific location being affected by one of seven biodiversity threats-agriculture, climate change, hunting, invasive species, logging, pollution, and urbanization. We conducted the analysis at a global scale, using a 50 km × 50 km grid, and evaluated the impact of these threats by studying their relationship with the risk of extinction. We find that climate change, logging, pollution, and invasive species are most linked to extinction risk. However, we also show that there is considerable geographical variation in these results. Our study highlights the importance of going beyond measuring the intensity of threats to measuring the impact of these separately for various biogeographical regions of the world, with different historical contingencies, as opposed to a single global analysis treating all regions the same.

BACKGROUND: The tomato leafminer, Phthorimaea absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a destructive invasive pest that originated in South America and has spread within China since 2017. A rapid method for on-site identification of P. absoluta is urgently needed for interception of this pest across China.
RESULTS: We developed a loop-mediated isothermal amplification (LAMP) technique to differentiate P. absoluta from Liriomyza sativae, Chromatomyia horticola, and Phthorimaea operculella using extracted genomic DNA, which was then refined to create an on-site LAMP diagnostic method that can be performed under field conditions without the need for laboratory equipment.
CONCLUSIONS: In the present research, we developed an on-site diagnostic method for rapid differentiation of P. absoluta from other insects with similar morphology or damage characteristics in China. © 2024 Society of Chemical Industry.

Invasive alien plants (IAPs) pose significant threats to native ecosystems and biodiversity worldwide. However, the understanding of their precise impact on soil carbon (C) dynamics in invaded ecosystems remains a crucial area of research. This review comprehensively explores the mechanisms through which IAPs influence soil C pools, fluxes, and C budgets, shedding light on their effects and broader consequences. Key mechanisms identified include changes in litter inputs, rates of organic matter decomposition, alterations in soil microbial communities, and shifts in nutrient cycling, all driving the impact of IAPs on soil C dynamics. These mechanisms affect soil C storage, turnover rates, and ecosystem functioning. Moreover, IAPs tend to increase gross primary productivity and net primary productivity leading to the alterations in fluxes and C budgets. The implications of IAP-induced alterations in soil C dynamics are significant and extend to plant-soil interactions, ecosystem structure, and biodiversity. Additionally, they have profound consequences for C sequestration, potentially impacting climate change mitigation. Restoring native plant communities, promoting soil health, and implementing species-specific management are essential measures to significantly mitigate the impacts of IAPs on soil C dynamics. Overall, understanding and mitigating the effects of IAPs on soil C storage, nutrient cycling, and related processes will contribute to the conservation of native biodiversity and complement global C neutrality efforts.

Invasive species control is important for ecological and agricultural management. Genetic methods can provide species specificity for population control. We developed heritable maternal effect embryo lethality (HMEL), a novel strategy allowing negative population pressure from HMEL individuals to be transmitted within a population across generations. We demonstrate the HMEL technique in zebrafish through genome-integrated CRISPR/Cas targeted mutagenic disruption of nucleoplasmin 2b (npm2b), a female-specific essential maternal effect gene, causing heritable sex-limited disruption of reproduction. HMEL-induced high-efficiency mutation of npm2b in females suppresses population, while males transmit the HMEL allele across generations. HMEL could be easily modified to target other genes causing sex-specific sterility, or generalized to control invasive fish or other vertebrate species for environmental conservation or agricultural protection.

The spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), an invasive planthopper discovered in Pennsylvania, U.S. in 2014, has spread to many surrounding states despite quarantines and control efforts, and further spread is anticipated. A classical (importation) biological control program would contribute to the long-term management of L. delicatula in the eastern U.S. In its native range of China, Anastatus orientalis (Hymenoptera: Eupelmidae), an egg parasitoid, causes significant mortality. Anastatus orientalis consists of multiple haplotypes that differ in important biological parameters. To delineate the physiological host range of A. orientalis Haplotype C, we completed no-choice and choice testing. No-choice testing of non-target eggs from 36 insect species spanning six orders and 18 families showed that physiologically this haplotype of A. orientalis can develop in a variety of host species eggs from the families Coreidae, Fulgoridae, Pentatomidae, and Saturniidae. Ten of the 16 species that were attacked in the no-choice tests were also attacked in the choice tests. The production of progeny on non-target egg masses was significantly lower than on the controls (L. delicatula egg masses run simultaneously) in the no-choice and choice tests. For the non-target species that were attacked and resulted in female wasp progeny, these females were able to produce their own progeny at the same rate as control females that were reared from the L. delicatula eggs. Larger host eggs corresponded to an increased female-biased sex ratio of the progeny, suggesting that gravid females select them for fertilized eggs. Results from these studies suggest that A. orientalis Haplotype C prefers to parasitize L. delicatula egg masses but is capable of developing in some non-target species.