Identifying pests in precision agriculture using low-cost image data acquisition.

Unmanned Aerial Vehicles (UAVs), often called drones, have gained progressive prevalence for their swift operational ability as well as their extensive applicability in diverse real-world situations. Of late, UAV usage in precision agriculture has attracted much interest from scientific community. This study will look at drone aid in precise farming. Big data has the ability to analyze enormous amounts of data. Due to this, it is one of the diverse crucial technologies of Information and Communication Technology (ICT) which had applied in precision agriculture for the abstraction of critical information as well as for assisting agricultural practitioners in the comprehension of the most feasible farming practices, and also for better decision-making. This work analyses communication protocols, as well as their application toward the challenge of commanding a drone fleet for protecting crops from infestations of parasites. For computer-vision tasks as well as data-intensive applications, the method of deep learning has shown much potential. Due to its vast potential, it can also be used in the field of agriculture. This research will employ several schemes to assess the efficacy of models includes Visual Geometry Group (VGG-16), the Convolutional Neural Network (CNN) as well as the Fully-Convolutional Network (FCN) in plant disease detection. The methods of Artificial Immune Systems (AIS) can be used in order to adapt deep neural networks to the immediate situation. Simulated outcomes demonstrate that the proposed method is providing superior performance over various other technologically-advanced methods.

DNA-based assessment of root lesion nematode infections in cereal roots.

Root lesion nematodes (RLN) of the genus Pratylenchus are causing significant damage in cereal production worldwide. Due to climate change and without efficient and environment-friendly treatments, the damages through RLNs are predicted to increase. Microscopic assessments of RLNs in the field and the greenhouses are time-consuming and laborious. As a result, cereal breeders have mostly ignored this pest. We present a method measuring RLN in infected cereal roots using a standardized PCR approach. Publicly available Pratylenchus neglectus primer combinations were evaluated. An optimal primer combination for RT-qPCR assay was identified to detect and quantify P. neglectus within infected cereal roots. Using the RT-qPCR detection assay, P. neglectus could be clearly distinguished from other plant parasitic nematodes. We could identify P. neglectus DNA in barley and wheat roots as low as 0.863 and 0.916 ng/µl of total DNA, respectively. A single P. neglectus individual was detected in water suspension and within barley and wheat roots. The RT-qPCR detection assay provides a robust and accurate alternative to microscopic nematode identification and quantification. It could be of interest for resistance breeding, where large populations must be screened to detect and quantify P. neglectus in farmer's fields.

Optimal Pest Control Strategies with Cost-effectiveness Analysis.

Pest and plant diseases cause damages and economic losses, threatening food security and ecosystem services. Thus, proper pest management is indispensable to mitigate the risk of losses. The risk of environmental hazards induced by toxic chemicals alongside the rapid development of chemical resistance by insects entails more resilient, sustainable, and ecologically sound approaches to chemical methods of control. This study evaluates the application of three dynamical measures of controls, namely, green insecticide, mating disruption, and the removal of infected plants, in controlling pest insects. A model was built to describe the interaction between plants and insects as well as the circulation of the pathogen. Optimal control measures are sought in such a way they maximize the healthy plant density jointly with the pests' density under the lowest possible control efforts. Our simulation study shows that all strategies succeed in controlling the insects. However, a cost-effectiveness analysis suggests that a strategy with two measures of green insecticide and plant removal is the most cost-effective, followed by one which applies all control measures. The best strategy projects the decrease of potential loss from 65.36% to 6.12%.

Crop rotation mitigates impacts of corn rootworm resistance to transgenic Bt corn.

Transgenic crops that produce insecticidal proteins from Bacillus thuringiensis (Bt) can suppress pests and reduce insecticide sprays, but their efficacy is reduced when pests evolve resistance. Although farmers plant refuges of non-Bt host plants to delay pest resistance, this tactic has not been sufficient against the western corn rootworm, Diabrotica virgifera virgifera In the United States, some populations of this devastating pest have rapidly evolved practical resistance to Cry3 toxins and Cry34/35Ab, the only Bt toxins in commercially available corn that kill rootworms. Here, we analyzed data from 2011 to 2016 on Bt corn fields producing Cry3Bb alone that were severely damaged by this pest in 25 crop-reporting districts of Illinois, Iowa, and Minnesota. The annual mean frequency of these problem fields was 29 fields (range 7 to 70) per million acres of Cry3Bb corn in 2011 to 2013, with a cost of $163 to $227 per damaged acre. The frequency of problem fields declined by 92% in 2014 to 2016 relative to 2011 to 2013 and was negatively associated with rotation of corn with soybean. The effectiveness of corn rotation for mitigating Bt resistance problems did not differ significantly between crop-reporting districts with versus without prevalent rotation-resistant rootworm populations. In some analyses, the frequency of problem fields was positively associated with planting of Cry3 corn and negatively associated with planting of Bt corn producing both a Cry3 toxin and Cry34/35Ab. The results highlight the central role of crop rotation for mitigating impacts of D. v. virgifera resistance to Bt corn.

Pest susceptibility, yield and fiber traits of transgenic cotton cultivars in Multan, Pakistan.

Cotton (Gossypium hirsutum L.), being a cash and fiber crop is of high significance in Pakistan. Numerous insect pests and viral diseases in Pakistan and around the world attack cotton crop. Genetically modified cotton (transgenic, resistant to lepidopteran insects), hereafter written as 'Bt-cotton' has been introduced in many regions of the world to combat bollworms. However, cultivars differ in their pest susceptibility, yield response and fiber quality traits. Nonetheless, recent studies have indicated that lepidopteran pests are evolving resistance against 'Bt-cotton'. Several 'Bt-cotton' cultivars have been developed in Pakistan in the past decade; however, limited is known about their pest susceptibility, seed-cotton yield and fiber quality traits. This two-year field study evaluated pest susceptibility, yield and fiber quality traits of thirteen newly developed 'Bt-cotton' cultivars in Pakistan. The cultivars differed in their susceptibility to sucking insects during both years of study. The cultivars 'FH-647', 'SLH-8', 'FH-Lalazar' and 'IUB-013' were more susceptible to jassid, whereas 'BS-52' exhibited higher susceptibility to whitefly during both years of study. Similarly, cultivars 'AGC-999' and 'MNH-992' proved highly susceptible to thrips during each study year. Although 'Bt-cotton' is resistant to bollworms, cultivars 'SLAH-8', 'VH-305' and 'BH-184' were susceptible to spotted bollworm, while 'SLAH-8', 'RH-647' and 'VH-305' were infested by American bollworm. The most susceptible cultivars to cotton leaf curl virus (CLCuV) attack were 'RH-647', 'IR-NIBGE-7' and 'VH-305'. The highest seed-cotton yield was recorded for 'FH-Lalazar' during both years of study. Similarly, the highest ginning out turn was recorded for cultivars 'BS-52', 'VH-305', 'RH-647', 'IUB' and 'AA-919'. The cultivar 'FH-Lalazar' exhibited low pest susceptibility and CLCuV infestation compared to the rest of cultivars. The highest and the lowest gross and net incomes and benefit:cost ratio were noted for 'FH-Lalazar' and 'RH-647, respectively. Keeping in view the low pest susceptibility and high seed-cotton yield, 'FH-Lalazar' could be recommended for higher yield and economic returns in Multan, Pakistan. Nonetheless, regional trials should be conducted for site-specific or region-specific recommendations.

Safety assessment of a new benzoylphenylurea TXH09 and its efficacy against two borers Ostrinia furnacalis and Grapholitha molesta in field.

Benzoylphenylureas as an important type of insect growth regulators, acting on the moulting stage in immature insects, are highly effective and low toxic. The new benzoylphenylurea TXH09 [N-((2,6-dimethyl-4-(heptafluoropropyl-2-yl)phenyl)carbamoyl)-2,6-difluorobenzamide] has high efficacy against chewing insect pests harming vegetables and rice. In this paper, the efficacy of TXH09 against two intractable borers Ostrinia furnacalis and Grapholitha molesta were evaluated in field, and safety assessment by exploring the characteristics of photodegradation, cytotoxicity, micronucleus generation and chromosome aberration was performed. The results showed that TXH09 had good capability in preventing infested corn and reducing the population of O. furnacalis larvae, and maintained high efficacy on shoot protection and peach conservation against G. molesta larvae. There were no significant differences between the control effects of TXH09 and that of hexaflumuron or diflubenzuron at the same active dose. TXH09 photolysis in solvents N,N-dimethylformamide, toluene and methanol yielded two major products, and the photodegradation of TXH09 was more prone to occur in N,N-dimethylformamide. TXH09 and the mixture of its photoproducts showed higher cytotoxicity on insect Sf-9 cells than on human Hek293 cells. Moreover, TXH09 didn't show significant effects in inducing micronucleated cells in both male and female mice and chromosomal aberrations in mouse spermatocytes by its own. In conclusion, TXH09, as an effective insecticide, has good environmental safety performance against O. furnacalis and G. molesta in field.

Sub-THz spectroscopic characterization identification for pine wood nematode ribosomal DNA.

This paper, we introduced Sub-terahertz (Sub-THz) technology to identify nematode DNA sequence. First, data mining technology and restriction enzyme digestion were used to cut out two corresponding sequences, each containing about 100 base pairs that could represent the characteristic fragments of Bursaphelenchus xylophilus (Bx) and Bursaphelenchus mucronatus (Bm) rDNA in internal transcribed spacer 1 (ITS1) region. Then, vibration spectra of the two enzyme-cut sequences were measured by Fourier transform infrared spectroscopy (FTIR). Meanwhile, the spectrum was analyzed by molecular dynamics method. It was found that the calculated and experimental spectra of the two enzyme-cut sequences were consistent, although the differences of the sequences could not be well reflected in the spectra. The vibration modes corresponding to diverse absorption peaks in the spectra were quite different, which were closely related to the internal bases sequencing. This can be used as an indicator for identifying Bx and Bm DNA. Moreover, the normal mode analysis (NMA) method was first adopted for spectral attribution analysis of DNA long sequences. Finally, the vibration spectra of shorter sequences predicted by second-order Markov chains and Monte Carlo method were studied. To some extent, the predicted short sequences can represent the complete sequence as the initial calculation structure.

Gb8, a new gene conferring resistance to economically important greenbug biotypes in wheat.

KEY MESSAGE: A new greenbug resistance gene Gb8 conferring broad resistance to US greenbug biotypes was identified in hard red winter wheat line PI 595379-1 and was mapped to the terminal region of chromosome 7DL. Greenbug [Schizaphis graminum (Rondani)] is a worldwide insect pest that poses a serious threat to wheat production. New greenbug resistance genes that can be readily used in wheat breeding are urgently needed. The objective of this study was to characterize a greenbug resistance gene in PI 595379-1, a single plant selection from PI 595379. Genetic analysis of response to greenbug biotype E in an F2:3 population derived from a cross between PI 595379-1 and PI 243735 indicated that a single gene, designated Gb8, conditioned resistance. Linkage analysis placed Gb8 in a 2.7-Mb interval in the terminal bin of chromosome 7DL (7DL3-082-1.0), spanning 595.6 to 598.3 Mb in the Chinese Spring IWGSC RefSeq version 1.0 reference sequence. Gb8 co-segregated with a newly developed SSR marker Xstars508, positioned at 596.4 Mb in the reference sequence. Allelism tests showed that Gb8 was different from three permanently named genes on the same chromosome arm and the estimated genetic distance between Gb8 and Gb3 was 15.35 ± 1.35 cM. Gb8 can be directly used in wheat breeding to enhance greenbug resistance.

Resource Allocation for Epidemic Control Across Multiple Sub-populations.

The number of pathogenic threats to plant, animal and human health is increasing. Controlling the spread of such threats is costly and often resources are limited. A key challenge facing decision makers is how to allocate resources to control the different threats in order to achieve the least amount of damage from the collective impact. In this paper we consider the allocation of limited resources across n independent target populations to treat pathogens whose spread is modelled using the susceptible-infected-susceptible model. Using mathematical analysis of the systems dynamics, we show that for effective disease control, with a limited budget, treatment should be focused on a subset of populations, rather than attempting to treat all populations less intensively. The choice of populations to treat can be approximated by a knapsack-type problem. We show that the knapsack closely approximates the exact optimum and greatly outperforms a number of simpler strategies. A key advantage of the knapsack approximation is that it provides insight into the way in which the economic and epidemiological dynamics affect the optimal allocation of resources. In particular using the knapsack approximation to apportion control takes into account two important aspects of the dynamics: the indirect interaction between the populations due to the shared pool of limited resources and the dependence on the initial conditions.

Resistance to Cereal Cyst Nematodes in Wheat and Barley: An Emphasis on Classical and Modern Approaches.

Cereal cyst nematodes (CCNs) are among the most important nematode pests that limit production of small grain cereals like wheat and barley. These nematodes alone are estimated to reduce production of crops by 10% globally. This necessitates a huge enhancement of nematode resistance in cereal crops against CCNs. Nematode resistance in wheat and barley in combination with higher grain yields has been a preferential research area for cereal nematologists. This usually involved the targeted genetic exploitations through natural means of classical selection breeding of resistant genotypes and finding quantitative trait luci (QTLs) associated with resistance genes. These improvements were based on available genetic diversity among the crop plants. Recently, genome-wide association studies have widely been exploited to associate nematode resistance or susceptibility with particular regions of the genome. Use of biotechnological tools through the application of various transgenic strategies for enhancement of nematode resistance in various crop plants including wheat and barley had also been an important area of research. These modern approaches primarily include the use of gene silencing, exploitation of nematode effector genes, proteinase inhibitors, chemodisruptive peptides and a combination of one or more of these approaches. Furthermore, the perspective genome editing technologies including CRISPR-Cas9 could also be helpful for improving CCN resistance in wheat and barley. The information provided in this review will be helpful to enhance resistance against CCNs and will attract the attention of the scientific community towards this neglected area.

Technical and economic efficiency of methods for extracting genomic DNA from Meloidogyne javanica.

Plant parasitic nematodes reduce the production of agricultural crops. Species diagnosis is essential to predict losses, determine economic damage levels and develop integrated pest management programs. DNA extraction techniques need to be improved for precise and rapid molecular diagnosis of nematodes. The objective of the present study was to evaluate the efficiency of DNA extraction and amplification by PCR, cost and execution time by Chelex, Worm Lysis Buffer Method (WLB), Holterman Lysis Buffer Method (HLB) and FastDNA methods for nematodes of the Meloidogyne genus. The qualitative and quantitative efficiency of DNA extraction varied between methods. The band size of the amplified PCR product with WLB, Chelex and HLB methods was 590 bp. Extraction with the FastDNA is not recommended for DNA extraction from nematodes because it results in a low DNA concentration without bands in PCR amplification, besides presenting high cost. The efficiency of the WLB method to extracting DNA from Meloidogyne javanica was greater, ensuring a higher concentration and purity of the extracted material and guaranteeing lower costs and greater ease of PCR amplification.

Optimal design for dynamical modeling of pest populations.

We apply SE-optimal design methodology to investigate optimal data collection procedures as a first step in investigating information content in ecoinformatics data sets. To illustrate ideas we use a simple phenomenological citrus red mite population model for pest dynamics. First the optimal sampling distributions for a varying number of data points are determined. We then analyze these optimal distributions by comparing the standard errors of parameter estimates corresponding to each distribution. This allows us to investigate how many data are required to have confidence in model parameter estimates in order to employ dynamical modeling to infer population dynamics. Our results suggest that a field researcher should collect at least 12 data points at the optimal times. Data collected according to this procedure along with dynamical modeling will allow us to estimate population dynamics from presence/absence-based data sets through the development of a scaling relationship. These Likert-type data sets are commonly collected by agricultural pest management consultants and are increasingly being used in ecoinformatics studies. By applying mathematical modeling with the relationship scale from the new data, we can then explore important integrated pest management questions using past and future presence/absence data sets.

Genetics of lineage diversification and the evolution of host usage in the economically important wheat curl mite, Aceria tosichella Keifer, 1969.

BACKGROUND: Understanding the mechanisms that underlie the diversification of herbivores through interactions with their hosts is important for their diversity assessment and identification of expansion events, particularly in a human-altered world where evolutionary processes can be exacerbated. We studied patterns of host usage and genetic structure in the wheat curl mite complex (WCM), Aceria tosichella, a major pest of the world's grain industry, to identify the factors behind its extensive diversification. RESULTS: We expanded on previous phylogenetic research, demonstrating deep lineage diversification within the taxon, a complex of distinctive host specialist and generalist lineages more diverse than previously assumed. Time-calibrated phylogenetic reconstruction inferred from mitochondrial DNA sequence data suggests that lineage diversification pre-dates the influence of agricultural practices, and lineages started to radiate in the mid Miocene when major radiations of C4 grasses is known to have occurred. Furthermore, we demonstrated that host specificity is not phylogenetically constrained, while host generalization appears to be a more derived trait coinciding with the expansion of the world's grasslands. Demographic history of specialist lineages have been more stable when compared to generalists, and their expansion pre-dated all generalist lineages. The lack of host-associated genetic structure of generalists indicates gene flow between mite populations from different hosts. CONCLUSIONS: Our analyses demonstrated that WCM is an unexpectedly diverse complex of genetic lineages and its differentiation is likely associated with the time of diversification and expansion of its hosts. Signatures of demographic histories and expansion of generalists are consistent with the observed proliferation of the globally most common lineages. The apparent lack of constrains on host use, coupled with a high colonization potential, hinders mite management, which may be further compromised by host range expansion. This study provides a significant contribution to the growing literature on host-association and diversification in herbivorous invertebrates.

Genome Sequences of Three Races of Peronospora effusa: A Resource for Studying the Evolution of the Spinach Downy Mildew Pathogen.

Downy mildew disease, caused by the obligate oomycete pathogen Peronospora effusa, is the most important economic constraint for spinach production. Three races (races 12, 13, and 14) of P. effusa have been sequenced and assembled. The draft genomes of these three races have been deposited to GenBank and provide useful resources for dissecting the interaction between the host and the pathogen and may provide a framework for determining the mechanism by which new races of the pathogen are rapidly emerging.

Cry1Ac production is costly for native plants attacked by non-Cry1Ac-targeted herbivores in the field.

Plants are the primary producers in most terrestrial ecosystems and have complex defense systems to protect their produce. Defense-deficient, high-yielding agricultural monocultures attract abundant nonhuman consumers, but are alternatively defended through pesticide application and genetic engineering to produce insecticidal proteins such as Cry1Ac (Bacillus thuringiensis). These approaches alter the balance between yield protection and maximization but have been poorly contextualized to known yield-defense trade-offs in wild plants. The native plant Nicotiana attenuata was used to compare yield benefits of plants transformed to be defenseless to those with a full suite of naturally evolved defenses, or additionally transformed to ectopically produce Cry1Ac. An insecticide treatment allowed us to examine yield under different herbivore loads in N. attenuata's native habitat. Cry1Ac, herbivore damage, and growth parameters were monitored throughout the season. Biomass and reproductive correlates were measured at season end. Non-Cry1Ac-targeted herbivores dominated on noninsecticide-treated plants, and increased the yield drag of Cry1Ac-producing plants in comparison with endogenously defended or undefended plants. Insecticide-sprayed Cry1Ac-producing plants lagged less in stalk height, shoot biomass, and flower production. In direct comparison with the endogenous defenses of a native plant, Cry1Ac production did not provide yield benefits for plants under observed herbivore loads in a field study.

The phenotypic and molecular assessment of the non-conserved Arabidopsis MICRORNA163/S-ADENOSYL-METHYLTRANSFERASE regulatory module during biotic stress.

In plants, microRNAs (miRNAs) have evolved in parallel to the protein-coding genes that they target for expression regulation, and miRNA-directed gene expression regulation is central to almost every cellular process. MicroRNA, miR163, is unique to the Arabidopsis genus and is processed into a 24-nucleotide (nt) mature small regulatory RNA (sRNA) from a single precursor transcript transcribed from a single locus, the MIR163 gene. The MIR163 locus is a result of a recent inverted duplication event of one of the five closely related S-ADENOSYL-METHYLTRANSFERASE genes that the mature miR163 sRNA targets for expression regulation. Currently, however, little is known about the role of the miR163/S-ADENOSYL-METHYLTRANSFERASE regulatory module in response to biotic stress. Here, we document the expression domains of MIR163 and the S-ADENOSYL-METHYLTRANSFERASE target genes following fusion of their putative promoter sequences to the ß-glucuronidase (GUS) reporter gene and subsequent in planta expression. Further, we report on our phenotypic and molecular assessment of Arabidopsis thaliana plants with altered miR163 accumulation, namely the mir163-1 and mir163-2 insertion knockout mutants and the miR163 overexpression line, the MIR163-OE plant. Finally, we reveal miR163 accumulation and S-ADENOSYL-METHYLTRANSFERASE target gene expression post treatment with the defence elicitors, salicylic acid and jasmonic acid, and following Fusarium oxysporum infection, wounding, and herbivory attack. Together, the work presented here provides a comprehensive new biological insight into the role played by the Arabidopsis genus-specific miR163/S-ADENOSYL-METHYLTRANSFERASE regulatory module in normal A. thaliana development and during the exposure of A. thaliana plants to biotic stress.

Degenerate ITS7 primer enhances oomycete community coverage and PCR sensitivity to Aphanomyces species, economically important plant pathogens.

Metagenomic analysis of oomycetes through deep amplicon sequencing has been conducted primarily using the ITS6-ITS7 primer set that targets the ITS1 region. While this primer set shows a perfect match to most oomycete taxa, ITS7 contains 3 mismatches to the corresponding binding site of plant pathogens within the genus Aphanomyces. Polymerase chain reaction (PCR) efficiency differs for taxa with uneven primer matching characteristics, which may explain why previous studies have detected this genus at low abundance. To overcome the impact of these mismatches on PCR sensitivity, the mismatched nucleotides were replaced with degenerate nucleotides. Oomycete communities from 35 soil samples collected from asymptomatic and root rot diseased sites in pea fields across Alberta were analyzed simultaneously using ITS6-ITS7 and ITS6-ITS7-a.e. (modified version of ITS7) primer sets on 1 Illumina MiSeq run. The number of high-quality reads obtained by ITS6-ITS7-a.e. was more than twice that of ITS6-ITS7. The relative abundance of Pythium spp. was reduced and Aphanomyces spp. increased. Aphanomyces cf. cladogamus and Aphanomyces euteiches were the second and third most abundant species, respectively, in the pea rhizosphere using the ITS7-a.e. primer, but were rare using the ITS7 primer. These results indicate that use of ITS7-a.e. provides a more accurate picture of oomycete communities than ITS7 by enhancing PCR sensitivity to Aphanomyces.

Soft selective sweeps in fungicide resistance evolution: recurrent mutations without fitness costs in grapevine downy mildew.

Adaptation produces hard or soft selective sweeps depending on the supply of adaptive genetic polymorphism. The evolution of pesticide resistance in parasites is a striking example of rapid adaptation that can shed light on selection processes. Plasmopara viticola, which causes grapevine downy mildew, forms large populations, in which resistance has rapidly evolved due to excessive fungicide use. We investigated the pathways by which fungicide resistance has evolved in this plant pathogen, to determine whether hard or soft selective sweeps were involved. An analysis of nucleotide polymorphism in 108 field isolates from the Bordeaux region revealed recurrent mutations of cytb and CesA3 conferring resistance to quinone outside inhibiting (QoI) and carboxylic acid amide (CAA) fungicides, respectively. Higher levels of genetic differentiation were observed for nucleotide positions involved in resistance than for neutral microsatellites, consistent with local adaptation of the pathogen to fungicide treatments. No hitchhiking was found between selected sites and neighbouring polymorphisms in cytb and CesA3, confirming multiple origins of resistance alleles. We assessed resistance costs, by evaluating the fitness of the 108 isolates through measurements of multiple quantitative pathogenicity traits under controlled conditions. No significant differences were found between sensitive and resistant isolates, suggesting that fitness costs may be absent or negligible. Our results indicate that the rapid evolution of fungicide resistance in P. viticola has involved a soft sweep.

Development of a pathway model to assess the exposure of European pine trees to pine wood nematode via the trade of wood.

Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a threat for pine species (Pinus spp.) throughout the world. The nematode is native to North America, and invaded Japan, China, Korea, and Taiwan, and more recently Portugal and Spain. PWN enters new areas through trade in wood products. Once established, eradication is not practically feasible. Therefore, preventing entry of PWN into new areas is crucial. Entry risk analysis can assist in targeting management to reduce the probability of entry. Assessing the entry of PWN is challenging due to the complexity of the wood trade and the wood processing chain. In this paper, we develop a pathway model that describes the wood trade and wood processing chain to determine the structure of the entry process. We consider entry of PWN through imported coniferous wood from China, a possible origin of Portuguese populations, to Europe. We show that exposure increased over years due to an increase in imports of sawn wood. From 2000 to 2012, Europe received an estimated 84 PWN propagules from China, 88% of which arose from imported sawn wood and 12% from round wood. The region in Portugal where the PWN was first reported is among those with the highest PWN transfer per unit of imported wood due to a high host cover and vector activity. An estimated 62% of PWN is expected to enter in countries where PWN is not expected to cause the wilt of pine trees because of low summer temperatures (e.g., Belgium, Sweden, Norway). In these countries, PWN is not easily detected, and such countries can thus serve as potential reservoirs of PWN. The model identifies ports and regions with high exposure, which helps targeting monitoring and surveillance, even in areas where wilt disease is not expected to occur. In addition, we show that exposure is most efficiently reduced by additional treatments in the country of origin, and/or import wood from PWN-free zones. Pathway modelling assists plant health managers in analyzing risks along the pathway and planning measures for enhancing biosecurity.