Background Soil erosion affects the stability of terrestrial ecosystems and ecosystem services by directly or indirectly impacting the cycling of soil materials and energy and reducing the fertility of grassland soils. However, research on microbial adaptation to grazing and soil erosion is limited, particularly in relation to grassland ecosystem restora-tion. Here, we assess microbial communities subjected to simulated soil erosion and grazing in a semi-arid grassland of Inner Mongolia, China.Results No significant change was observed in soil variables. However, the structure of the soil microbial commu-nity underwent significant changes as a result of soil erosion and soil erosion plus grazing, leading to a significant increase in the relative abundance of Cyanobacteria(116.80% vs 116.38%). Wind erosion and deposition contributed to an increase in the network complexity of soil bacterial and fungal communities. However, much of this effect was alleviated by grazing. Simultaneously, aeolian processes and grazing regulate soil microbial community assembly, leading to inconsistent patterns of change in bacterial and fungal communities. Under wind erosion and deposi-tion, the relative contribution of deterministic processes(4.44% vs 31.11%) in bacterial communities increased, while the relative contribution of stochastic processes(2.23% vs 20%) in fungal communities reduced. Grazing resulted in a decrease in the relative contribution of deterministic processes(8.89%) in the bacterial community and an increase in the relative contribution of stochastic processes(8.89%) in the fungal community.Conclusion This study presents a comprehensive investigation of the response of soil microbial communities to aeolian erosion–deposition and grazing in a semi-arid grassland. Our findings indicate that microbial communities in the semi-arid grassland show resistance to external disturbances and that light grazing mitigates the effects of aeo-lian erosion–deposition on microbial communities, which is essential for maintaining the stability and biodiversity of grassland ecosystems.
Biological invasions pose significant threats to ecological and economic stability, with invasive pests like the Asian longhorned beetle (Anoplophora glabripennis Motschulsky, ALB) causing substantial damage to forest ecosystems. Effective pest management relies on comprehensive knowledge of the insect's biology and invasion history. This study uses genomics to address these knowledge gaps and inform existing biosurveillance frameworks. We used 2768 genome-wide single nucleotide polymorphisms to compare invasive A. glabripennis populations in North America, using genomic variation to trace their sources of invasion and spread patterns, thereby refining our understanding of this species' invasion history. We found that most North American A. glabripennis infestations were distinct, resulting from multiple independent introductions from the native range. Following their introduction, all invasive populations experienced a genetic bottleneck which was followed by a population expansion, with a few also showing secondary spread to satellite infestations. Our study provides a foundation for a genome-based biosurveillance tool that can be used to clarify the origin of intercepted individuals, allowing regulatory agencies to strengthen biosecurity measures against this invasive beetle.
Anoplophora glabripennis (Asian longhorn beetle, ALB) and Anoplophora chinensis (Citrus longhorn beetle, CLB) are native forest pests in China; they have become important international quarantine pests. They are found using the same Salix aureo‐pendula host tree of Cixi, Zhejiang province, China. On this host tree, we collected additional beetles that appeared to be morphologically intermediate between ALB and CLB. By using a stereoscope, we observed that there were several bumps on the base of the elytra, which was inconsistent with ALB, which typically has a smooth elytral base, but was more like CLB, which has numerous short tubercles on the elytral base. Given their sympatry and intermediate morphology, we hypothesized that these may represent ALB × CLB hybrids. We studied the genomic profiles for 46 samples (ALB, CLB, and putative hybrids) using genotyping‐by‐sequencing (GBS) providing a reduced representation of the entire genome. Employing principal component analyses on the 163 GBS‐derived single nucleotide polymorphism data, we found putative hybrids tightly clustered with ALB, but genetically distinct from the CLB individuals. Therefore, our initial hybrid hypothesis was not supported by genomic data. Further, while mating experiments between adult ALB and CLB were successful in 4 separate years (2017, 2018, 2020, and 2021), and oviposition behavior was observed, no progeny was produced. Having employed population genomic analysis and biological hybridization experiments, we conclude that the putative hybrids represent newly discovered morphological variants within ALB. Our approach further confirmed the advantage of genome‐wide information for Anoplophora species assignment in certain ambiguous classification cases.
The Asian longhorn beetle (ALB) Anoplophora glabripennis is one of the most successful and most feared invasive insect species worldwide. This review covers recent research concerning the distribution of and damage caused by ALB, as well as major efforts to control and manage ALB in China. The distribution and destruction range of ALB have continued to expand over the past decade worldwide, and the number of interceptions has remained high. Detection and monitoring methods for the early discovery of ALB have diversified, with advances in semiochemical research and using satellite remote sensing in China. Ecological control of ALB in China involves planting mixtures of preferred and resistant tree species, and this practice can prevent outbreaks. In addition, strategies for chemical and biological control of ALB have achieved promising results during the last decade in China, especially the development of insecticides targeting different stages of ALB, and applying Dastarcus helophoroides and Dendrocopos major as biocontrol agents. Finally, we analyze recommendations for ALB prevention and management strategies based on native range and invasive area research. This information will hopefully help some invaded areas where the target is containment of ALB.
Human-assisted movement has allowed the Asian longhorned beetle (ALB, Anoplophora glabripennis (Motschulsky)) to spread beyond its native range and become a globally regulated invasive pest. Within its native range of China and the Korean peninsula, human-mediated dispersal has also caused cryptic translocation of insects, resulting in population structure complexity. Previous studies used genetic methods to detangle this complexity but were unable to clearly delimit native populations which is needed to develop downstream biosurveillance tools. We used genome-wide markers to define historical population structure in native ALB populations and contemporary movement between regions. We used genotyping-by-sequencing to generate 6102 single-nucleotide polymorphisms (SNPs) and amplicon sequencing to genotype 53 microsatellites. In total, we genotyped 712 individuals from ALB's native distribution. We observed six distinct population clusters among native ALB populations, with a clear delineation between northern and southern groups. Most of the individuals from South Korea were distinct from populations in China. Our results also indicate historical divergence among populations and suggest limited large-scale admixture, but we did identify a restricted number of cases of contemporary movement between regions. We identified SNPs under selection and describe a clinal allele frequency pattern in a missense variant associated with glycerol kinase, an important enzyme in the utilization of an insect cryoprotectant. We further demonstrate that small numbers of SNPs can assign individuals to geographic regions with high probability, paving the way for novel ALB biosurveillance tools.
The functional diversity of arbuscular mycorrhizal fungi (AMF) affects the resistance and resilience of plant communities to environmental stress. However, considerable uncertainty remains regarding how the complex interactions among elevated atmospheric CO2 (eCO2), nitrogen deposition (eN), precipitation (eP), and warming (eT) affect AMF communities. These global change factors (GCFs) do not occur in isolation, and their interactions likely affect AMF community structure and assembly processes. In this study, the interactive effects of these four GCFs on AMF communities were explored using an open-top chamber field experiment in a semiarid grassland. Elevated CO2, eN, eT, eP, and their interactions did not affect AMF biomass. The relative abundance of Paraglomus increased with N addition across treatment combinations, whereas that of Glomus decreased with N addition, especially combined with eT and eCO2. Precipitation, temperature (T), and N affected AMF phylogenetic α-diversity, and the three-way interaction among CO2, T, and N affected taxonomic and phylogenetic α-diversity. N addition significantly affected the composition of AMF communities. Both variable selection and dispersal limitation played major roles in shaping AMF communities, whereas homogeneous selection and homogenizing dispersal had little effect on AMF community assembly. The contribution of variable selection decreased under eCO2, eN and eT but not under eP. The contribution of dispersal limitation decreased under eCO2, eT, and eP but increased under eN. The assembly of AMF communities under the sixteen GCF combinations was strongly affected by dispersal limitation, variable selection and ecological drift. Elevated CO2, warming, N addition, and increased precipitation affected different aspects of AMF communities. The interactive effects of the four GCFs on AMF communities were limited. Overall, the results of this study suggest that AMF communities in semiarid grasslands can resist changes in global climate.
BackgroundThe functional diversity of arbuscular mycorrhizal fungi ( AMF) affects the resistance and resilience of plant communities to environmental stresses. However, considerable uncertainty remains about how the complex interactions among elevated atmospheric CO 2 (eCO 2 ), nitrogen deposition (eN), increased precipitation (eP), and warming (eT) affect AMF communities. These global change factors (GCFs) always occur simultaneously, and their interactions likely affect AMF community structure and assembly processes. In this study, the interactive effects of these four GCFs on AMF communities were explored in an open-top chamber field experiment in a semiarid grassland. ResultsElevated CO 2 , eN, eT, and eP and their interactions did not affect AM fungal biomass. The relative abundance of Paraglomus increased with N addition across treatment combinations, whereas that of Glomus decreased with N addition, especially combined with eT and eCO 2 . Precipitation, T, and N affected AMF phylogenetic α-diversity, and the three-way interaction among CO 2 , T, and N affected taxonomic and phylogenetic α-diversity. Nitrogen addition significantly affected the β-diversity of AMF communities. Both variable selection and dispersal limitation played major roles in shaping AMF communities, whereas homogeneous selection and homogenizing dispersal had almost no influence on AMF community assembly. The contribution of variable selection decreased under eCO 2 , eN and eT, but not under eP. The contribution of dispersal limitation decreased under eCO 2 , eT, and eP but it increased under eN. The assembly of AMF communities under the sixteen GCF combinations was strongly influenced by dispersal limitation, variable selection and ecological drift. ConclusionsElevated CO 2 , warming, N addition, and increased precipitation influenced different aspects of AMF communities. The interactive effects of the four GCFs on AMF communities were limited. Collectively, the results of this study suggest that AMF communities in semiarid grasslands can resist changes in the global climate.
Global ecosystem functions, services, and commodities are increasingly threatened by biological invasions. As a result, there is an urgent need to manage invasive species through global collaborative research. We propose an 'applied empirical framework' (AEF) to aggressively confront the current global biological invasion crisis. The AEF builds on existing models for invasion science that advocate 1) standardized research designs to reveal key aspects of biological invasion, and 2) collaborative research to facilitate the sharing of resources and information. The AEF further emphasizes the need for 3) the production of research 'tools' (e.g., data, methodologies, technical instruments) designed for direct uptake by agencies that manage biological invasion, and 4) a taxonomically targeted approach in which task forces conduct rapid, in-depth research on top-priority invasive species across their entire geographic range. We review collaborative science and the distinctive roles played by different collaborator types. We then provide an example of the AEF in action through the BioSAFE initiative (Biosurveillance of Alien Forest Enemies), a highly collaborative project aimed at developing genomic research tools to facilitate biosurveillance and intervention for forest invasive species. We illustrate the BioSAFE approach through our research on two polyphagous insect species: the wood-borer Anoplophora glabripennis, Motschusky (Coleoptera: Cerambycidae; Asian longhorned beetle) and the defoliator Lymantria dispar, Linnaeus spp. (Lepidoptera: Lymantriidae; gypsy moth). These examples illustrate how the AEF can focus and accelerate our response to the global biological invasion crisis by applying the resource capabilities of collaborative research groups to generate management tools for top-priority invasive species.
Invasive species pose significant threats to forest ecosystems. Early intervention strategies are the most cost-effective means to control biological invasions, but are reliant on robust biosurveillance. State-of-the-art genomic approaches can provide an unprecedented opportunity to access detailed information on the invasion process and adaptive potential of invasive insects that pose an immediate threat to forests environments. Genomics can improve diagnostics of the invader and identify its route of invasion by determining the source population(s), assess its probability of establishment and patterns of spread, as well as provide evidence of adaptation. Applied biosurveillance efforts by plant health regulatory agencies will benefit substantially from the detailed insights that genomic data bring to our understanding of biological invasions.
Early intervention, effective management, and regulations are essential to mitigate the potential negative impacts of invasive forest insects. Biosurveillance provides the necessary knowledge to inform management, and regulatory practices. Genomic approaches can contribute valuable information to this process. Unfortunately, adoption and incorporation of genomic tools into biosurveillance frameworks is not straightforward. To realize the full potential of genomic knowledge, researchers must work together with end users to ensure full adoption, standardization, validation, and interpretation of genomic results.
Seabuckthorn carpenter moth, Eogystia hippophaecolus (Lepidoptera: Cossidae), is an important pest of sea buckthorn (Hippophae rhamnoides), which is a shrub that has significant ecological and economic value in China. E. hippophaecolus is highly cold tolerant, but limited studies have been conducted to elucidate the molecular mechanisms underlying its cold resistance. Here we sequenced the E. hippophaecolus transcriptome using RNA-Seq technology and performed de novo assembly from the short paired-end reads. We investigated the larval response to cold stress by comparing gene expression profiles between treatments. We obtained 118,034 unigenes, of which 22,161 were annotated with gene descriptions, conserved domains, gene ontology terms, and metabolic pathways. These resulted in 57 GO terms and 193 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. By comparing transcriptome profiles for differential gene expression, we identified many differentially expressed proteins and genes, including heat shock proteins and cuticular proteins which have previously been reported to be involved in cold resistance of insects. This study provides a global transcriptome analysis and an assessment of differential gene expression in E. hippophaecolus under cold stress. We found seven differential expressed genes in common between developmental stages, which were verified with qPCR. Our findings facilitate future genomic studies aimed at improving our understanding of the molecular mechanisms underlying the response of insects to low temperatures.
Eogystia hippophaecolus is a major borer pest of sea buckthorn in China, damaging the environment and sea buckthorn industry. It is widely distributed in the Three-North region of China, and its larvae are resistant to low temperatures. Because heat-shock protein 70 can repair misfolded proteins under low temperatures, thus preventing cell damage and improving tolerance, we investigated the adaptation of E. hippophaecolus HSP70. We screened the transcriptome of E. hippophaecolus for HSP70 homologs, identified a full-length gene, and cloned to obtain the open reading frame, which was 1896 bp in length and encoded 631 amino acids, with a molecular weight of 69.7 kDa. The amino acid sequence contained three signature sequences of the HSP70 family and a C-terminal cytoplasmic character sequence. A phylogenic tree demonstrated that EhHSP70 has high homology with HSP70 genes from other insect species. We measure expression of the HSP70 gene across tissues when larvae of E. hippophaecolus were cold shocked. We also measured expression during cold shock recovery. EhHSP70 expression varied across tissues at 25 degrees C, with the highest expression in the midgut. Compared with the control, the expression of EhHSP70 in the cuticle was fourfold higher after a cold shock of -5 degrees C for 1 h. EhHSP70 expression was also significantly increased during the 1-h period following recovery from cold shock, then decreased. In summary, cold shock promoted the expression of EhHSP70, which may play an important role in the adaptation mechanism of cold tolerance in E. hippophaecolus larvae.
In order to exploit SSR information of Eogystia hippophaecolus,we identify EST-SSR loci and analyze their features according to the transcriptome of E.hippophaecolus.Results show 5126 unigenes contain 7499 SSR loci in total (51.41%).Mononucleotide repeats predominated with an occurrence frequency of 39.52%.There are 77 kinds of repeat motifs existing in E.hippophaecolus transcriptome.(A/T)n (73.74%) is most frequent in all the repeat types,and next is (AT/AT) n (3.37%).Most of the SSR are less than ten times of repetition and are 10 bp in length.The results should contribute to researches in SSR marker,genetic diversity,population genetic structure and genomic signatures identification in E.hippophaecolus.
Olfactory proteins form the basis of insect olfactory recognition, which is crucial for host identification, mating, and oviposition. Using transcriptome analysis of Anoplophora glabripennis antenna, we identified 42 odorant-binding proteins (OBPs), 12 chemosensory proteins (CSPs), 14 pheromone-degrading enzymes (PDEs), 1 odorant-degrading enzymes (ODE), 37 odorant receptors (ORs), 11 gustatory receptors (GRs), 2 sensory neuron membrane proteins (SNMPs), and 4 ionotropic receptor (IR). All CSPs and PBPs were expressed in antennae, confirming the authenticity of the transcriptome data. CSP expression profiles showed that AglaCSP3, AglaCSP6, and AglaCSP12 were expressed preferentially in maxillary palps and AglaCSP7 and AglaCSP9 were strongly expressed in antennae. The vast majority of CSPs were highly expressed in multiple chemosensory tissues, suggesting their participation in olfactory recognition in almost all olfactory tissues. Intriguingly, the PBP AglaPBP2 was preferentially expressed in antenna, indicating that it is the main protein involved in efficient and sensitive pheromone recognition. Phylogenetic analysis of olfactory proteins indicated AglaGR1 may detect CO2. This study establishes a foundation for determining the chemoreception molecular mechanisms of A. glabripennis, which would provide a new perspective for controlling pest populations, especially those of borers.
BACKGROUND:Eogystia hippophaecolus (Hua et al.) (Lepidoptera: Cossidae) is the major threat to seabuckthorn plantations in China. Specific and highly efficient artificial sex pheromone traps was developed and used to control it. However, the molecular basis for the pheromone recognition is not known. So we established the antennal transcriptome of E. hippophaecolus and characterized the expression profiles of odorant binding proteins. These results establish and improve the basis knowledge of the olfactory receptive system, furthermore provide a theoretical basis for the development of new pest control method.RESULTS:We identified 29 transcripts encoding putative odorant-binding proteins (OBPs), 18 putative chemosensory proteins (CSPs), 63 odorant receptors (ORs), 13 gustatory receptors (GRs), 12 ionotropic receptors (IRs), and two sensory neuron membrane proteins (SNMPs). Based on phylogenetic analysis, we found one Orco and three pheromone receptors of E. hippophaecolus and found that EhipGR13 detects sugar, EhipGR11 and EhipGR3 detect bitter. Nine OBPs expression profile indicated that most were the highest expression in antennae, consistent with functions of OBPs in binding and transporting odors during the antennal recognition process. OBP6 was external expressed in male genital-biased in, and this locus may be responsible for pheromone binding and recognition as well as mating. OBP1 was the highest and biased expressed in the foot and may function as identification of host plant volatiles.CONCLUSIONS:One hundred thirty-seven chemosensory proteins were identified and the accurate functions and groups of part proteins were obtained by phylogenetic analysis. The most OBPs were antenna-biased expressed, which are involved in antennal recognition. However, few OBP was detected biased expression in the foot and external genitalia, and these loci may function in pheromone recognition, mating, and the recognition of plant volatiles.