Archive for the ‘Emerging/invasive pests’ Category


Fall armyworm feeding on sorghum in Niger

 How do we fight the Fall armyworm, the new wound of African agriculture ?

Two years after its first detection in West Africa, this invasive caterpillar is threatening the food security of millions of small farmers in over 30 African countries. To solve the future food needs in sub-Saharan Africa, entomologists must be a critical part of the puzzle. From Nigeria to Ethiopia, South Africa to Chad, African smallholder farmers often face severe crop losses from damaging bugs from locusts to cassava’s whiteflies, cowpea pod borers or maize and sorghum stem borers. According to the Center for Agriculture and Biosciences International (CABI), pests, (some emerging due to climate change or shifts in land use), reduce African crop harvests by 50%. Most smallholder farmers don’t have the ability to diagnose crop problems quickly and often have no means or knowledge to control these pests. With climate change and increased movement of goods and people, emerging pests will worsen an already serious problem.

Now, a foreign caterpillar from the Americas, the fall armyworm (FAW) Spodoptera frugiperda is quickly invading the continent, swallowing entire fields of maize, but also sorghum, millets and many other staple crops.  There were already armyworms in Africa –worldwide – but the fall armyworm is particularly voracious and versatile, and spreads fast. Targeting over 80 crop species, the caterpillar eats day and night. It’s life cycle can be as short as 30 days and the adult moth is able to fly 100km a night. It is no surprise then that it has invaded over 30 African countries since it was first reported in Nigeria in early 2016. The pest poses a serious threat to the food and nutrition security of millions of farming households in sub-Saharan Africa. According to CABI, the FAW could potentially cause maize yield losses in a range from 8.3 to 20.6 million tons annually in Africa, worth between 2.5 and 6.2 billion dollars, in the absence of any means of control, in just 12 maize-producing countries. But FAW attacks concern also many other important food crops including sorghum and millets, where damages were reported for example in Ethiopia, Kenya, Malawi, Mali, Niger and Rwanda. So what could be the response to this pest problem that is here to stay?

Chemical or natural ways to control the FAW 

Looking at what happens in their native lands in Americas, when caterpillars damage over a quarter of the crop field, systemic pesticides are recommended. Some scientists have noted in the past some excesses which have harmed farmers health and the environment without economic sense, alongside building FAW’s pesticide resistance. Pesticide use may be considered against FAW invasion – plant breeders on ICRISAT research stations used it this summer to protect their experiments – but most of the chemicals that control FAW are not tested and registered in most African countries. Therefore, there is a need to evaluate and fast track registration of effective chemicals for the control FAW. This chemical response is however expensive and often out of reach of most smallholders, and will certainly not be used for their staple food like sorghum and millet.

Natural ways to combat FAW can be an efficient and appropriate approach. Biological control, ie the use of natural enemies of a pest, is a successful approach for many devastating insects like pearl millet head borer which can be almost eradicated by parasitic wasps. FAW has several enemies (predators, parasitoids and pathogens) in its native continent but they may be different than the enemies of the local armyworms species. It is advised to list an inventory of possible natural enemies present in Africa, focusing on parasitoid Telenomus wasps, which control quite well the population of FAW in the Americas. About 11 Telenomus species parasitizing many Lepidoptera insects in Africa could be tested for effectiveness against FAW.  If no indigenous biological control is effective, some parasitoids could be introduced from the Americas after careful pre-release studies. After defining the effective biological control methods, local production of parasitoids should be set up. This could however take years.

Biological pesticides such as the spray application of Bacillus thuringiensis or nuclear polyhedrosis virus (NPVSf) have shown good results against FAW and could be tested in the context of African farms. However, this solution could be out of reach for most small farmers.

Plants also have the extraordinary capacity to repel or attract insects by emitting specific volatiles. Some “call” caterpillar enemies, such as wasp parasitoids, when the caterpillar starts feeding on the plant. Other plants repel – like the tropical forage legume Desmodium – or attract FAW. A push-pull strategy using Desmodium as intercrop and Brachiaria another forage crop as border can reduce by more than 80% FAW damage as this recent study from the International Center of Insect Physiology and Ecology (ICIPE) shows. Such habitat management approaches including crop rotations, intercropping with compatible companion crops and conservation agriculture need to be tested as such options are more manageable for smallholder farmers.

Developing and distributing resistant varieties could be central to an Integrated Pest Management strategy against FAW. ICRISAT has already developed sorghum lines resistant to stem borer (Lepidoptera) that will be evaluated for responses to FAW, working closely with EMBRAPA-Brazil who has in the past screened sorghum germplasm for FAW resistance. Two potential sorghum lines have been identified in the ICRISAT Genebank, which could be useful for breeding for FAW resistance.

Yet, this breeding effort will also take several years to achieve results, and then there will be the “seed systems challenge” of disseminating these improved seeds to farmers.

Providing a rapid response to African smallholder farmers

While FAO and other players are debating big plans to combat FAW, African smallholder farmers need fast responses to save their harvests in the months to come, faster than plant breeding, biopesticides or biological control. If we take a closer look at the insect cycle and impact on the plant, may be it is a change of perspective that is needed.

First we need to know the extent of the problem. Mobile technologies could help map in real-time the exact location of the attacks. With the fast adoption of smartphones across the continent (about 300 million users already), African farmers could access mobile plant diagnosis applications such as Plantix to check if their field is affected by FAW – there are 30 different types of armyworms (Spodoptera genus), some other than the fall species, creating havoc in some Indian States this year due to favorable weather conditions – and report it to the online community. FAW Hot spots mapping could help assess the damages, understand and forecast future outbreaks and plan long-term FAW management.

Farmers may also have to accept limited damages to the adult crop up to a certain level, let’s say 20%, and invest on protecting seedlings with affordable seed treatment, coating seeds with an appropriate pesticide and fertilizer blend that would protect the seedlings to avoid total wipe out of the crop if the caterpillar attacks early. When feeding on seedlings, FAW may eat buds and tipping points, killing the plant.

Seed treatment is far more affordable for small farmers than spraying the field when the crop has matured, and worth the investment. In West Africa, ICRISAT scientists have demonstrated that 2$/ha of millet and sorghum seed treatment with Apron Star could protect seedlings from pests and fungi up to 40 days, improve crop density by a quarter and yields by up to 50%. Training of farmer organizations and the distribution of small packs of seed treatment, could be implemented quite quickly with the right public private partnership.

While the presence of the fall armyworm is now irreversible in Africa, as insects know no borders, there is now a collective international effort to control its damage. The scope and speed of fall armyworm destruction show how African smallholder farming is vulnerable to emerging risks. It is important that varied approaches to tackle this emerging pest are explored, from biological control, biopesticides to pest tolerance crop breeding. But because so many farming families have no other livelihoods and safety nets, research should focus also on delivering scalable and affordable solutions for the next season.

About the authors

Jerome Bossuet
Co-Head – Communications and Partnerships
Strategic Marketing & Communication
Dr Malick Niango Ba
Country Representative – Niger
West & Central Africa Program

Article page: Click here


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VA Tech logo

Invasive plants have surprising ability to pioneer new continents and climates, Virginia Tech researchers discover

December 4, 2017

Velvetleaf plant
Velvetleaf represents one of the many invasive plant species that was tested by Dan Atwater and Jacob Barney.

Virginia Tech scientists have discovered that invasive plant species are essentially able to change in order to thrive on new continents and in different types of climates, challenging the assumption that species occupy the same environment in native and invasive ranges.

It’s no secret that globalization, aided by climate change, is helping invasive species gain a foothold across the planet, but it was something of a surprise to Virginia Tech researchers just how mutable these invaders are.

The study, by Jacob Barney, an associate professor in the College of Agriculture and Life Sciences’ Department of Plant Pathology, Physiology, and Weed Science, and Dan Atwater, a lecturer in the Department of Biological Sciences at North Carolina State University and Barney’s former post-doctoral advisee, was published Dec. 4 in Nature Ecology and Evolution, a new online journal.

Two Virginia Tech researchers
Dan Atwater, left, and Jacob Barney examined 815 terrestrial plant species from every continent, along with millions of occurrence points, and compared models in the largest global invasive species study to date.

“This is important for both changing how we think about species and where they grow,” said Barney, who is also a fellow in the Fralin Life Science Institute and an affiliate of the Global Change Center. “The findings also change our ability to predict where they will grow and how they may respond in a changing climate. This could be a game-changer for invasive species risk assessment and conservation.”

Atwater used data compiled by undergraduate Carissa Ervine, also an author on the paper, to test a long-held assumption in ecology – that the climate limitations of plants do not change, which means we can predict where they will grow. Small studies supported this supposition. However, the Virginia Tech researchers blew this assumption away by testing more than 800 species using new models developed by Atwater and Barney.

“Some people would say that invasive species have different distributions in a new climate. But we found they are occupying a wider range of new climates,” said Atwater. “Species are changing in their ecology when they move from one continent to another. We should expect species to change, possibly permanently, when they cross continents.”

The results have major consequences for applying environmental niche models to assess the risk of invasive species and for predicting species’ responses to climate change. Species capable of changing their ecology and the climates they call home may pose a challenge to researchers using native range data to forecast the distribution of invasive species.

The driver behind the study was a desire to forecast the future distribution of invasive species, which pose a serious threat to human, environmental, and economic health. The researchers began by posing the question: Do invasive species occupy the same climate in invasive range that they do in their native range? To find out, they compared native and invasive species.

Barney and Atwater examined 815 terrestrial plant species from every continent, along with millions of occurrence points, or locations where the plants have been known to occur, and compared models in the largest global invasive species study to date. They found evidence of climatic niche shifts in all of the 815 plant species introduced across five continents. A climatic niche refers to the set of climates in which a species has a stable or growing population.

Generally, their findings suggest that niche shifts reflect changes in climate availability at the continent scale and were the largest in long-lived and cultivated species. If species move to a warmer continent, for instance, they tend to shift toward occupying warmer climates. In short, cultivated plants with long lifespans are particularly adept at making themselves home in new climates.

“There are not only implications for predicting where invasive species will occur, there are management repercussions as well,” said Barney. “As an example, for certain species we use biocontrol, introducing one organism to control another, an approach that may not be effective or safe if the targeted species undergoes ecological change. When we do climate modeling, we assume the climate niche may be the same when it may not be. So, there are a broad range of implications in a broad range of fields.”

Barney raised another concern.

“By cultivating species — bending them for agricultural or ornamental purposes and selecting for traits, such as cold-hardiness, we push them into environments they would not have occupied,” he said. “Those selection pressures in breeding, plus the environments we put them in, may exaggerate this change. Short-lived species, for example, go into dryer climates. So the take home is that different species’ traits influence the direction of a niche shift.”

Once Atwater and Barney understand these drivers more fully, they hope to be able to predict how the geographic range of an invasive species will increase in order to pinpoint areas likely to be invaded.

“The other piece layered onto this is the assumption that the climate is stable, which is not the case,” said Atwater. “We have also relied on the assumption that a species is a species and its ecological tendencies remain constant. This too is not the case. Species vary in space and time. They behave differently on different continents and in different climates. Consequently, the concept of a species climatic niche is less stable and less clearly defined.”

With food production, human health, ecosystem resilience, and biodiversity at stake as global invasions outpace our ability to respond, a greater understanding of climatic niche shifts is critical to future attempts to forecast species dynamics, according to the researchers.


—      Written by Amy Painter



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IPM IL Logotuta larva on tomato (2)iapps-logo3

The 12th Arab Congress of Plant Protection was held in Hurghada, Egypt, from November 4-10, 2017. There were about 300 participants from Egypt, Syria, Lebanon, Jordan, Sudan, Tunisia, Algeria, Morocco, Pakistan, Italy, and the U.S.A. Participating regional and international organizations were FAO, EPPO, CIMMYT, ICARDA and CIHEAM. Prof. R. Muniappan, Director, IPM Innovation Lab, representing IAPPS in this congress,              presented a keynote address entitled, “Building Bridges between Plant Protection Disciplines for Sustainable Crop Protection”. Key symposia included the South American tomato leafminer, Tuta absoluta.

ARab cong tuta sym particpants

Participants in the South American tomato leafminer, Tuta absoluta, symposium.



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From the Aliens’ list/PestNet

From: Arne Witt <a.witt@cabi.org>
Date: 9 November 2017 at 20:25
Subject: [Aliens-L] FAW

New report reveals cost of Fall Armyworm and provides recommendations for control



The report, commissioned by the UK’s Department for International Development (DFID), reviews the current evidence of the potential impact of the pest and quantifies the likely economic effect on agricultural sectors in affected countries and regions if left unmanaged.

In the absence of any control methods, we estimate that the pest has the potential to cause huge maize yield losses in Africa and we expect it to spread throughout suitable habitats in mainland sub-Saharan Africa within the next few cropping seasons. Northern Africa and Madagascar are also at risk. This would clearly have a huge impact on food security and the achievement of SDG 2 (Zero Hunger).

Control of Fall Armyworm requires an integrated pest management (IPM) approach and immediate recommendations we make in the report include raising awareness on Fall Armyworm symptoms, early detection and control, and the creation and communication of a list of recommended, regulated pesticides and biopesticides to control the pest. Work must also start to assess which crop varieties can resist or tolerate Fall Armyworm. In the longer run national policies should promote lower risk control options through short term subsidies and rapid assessment and registration of biopesticides and biological control products.

To see the reports:

Download the 10 page summary of the evidence note

Download the full evidence note


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Penn State News

Via PestNet


Spotted lanternfly adult - lateral view

The spotted lanternfly threatens agricultural sectors worth nearly $18 billion to Pennsylvania’s economy.

Image: Greg Hoover


UNIVERSITY PARK, Pa. — As populations of the invasive spotted lanternfly explode — and the state-imposed quarantine area in southeastern Pennsylvania expands — researchers in Penn State’s College of Agricultural Sciences are looking for solutions to help stop the insect’s spread and save agricultural crops from serious damage.

The spotted lanternfly was found for the first time in the United States in Berks County in September 2014. More than three years later, the Pennsylvania Department of Agriculture’s quarantine, which began with five townships in eastern Berks County, now covers all of Berks, Bucks, Chester, Lehigh, Montgomery, Northampton, Carbon, Delaware, Lancaster, Lebanon, Monroe, Philadelphia and Schuylkill counties. The quarantine regulates or limits the movement of plants, plant-based materials and outdoor household items out of the quarantine area unless certain conditions are met.

Officials are worried about the threat the spotted lanternfly poses to Pennsylvania agriculture, including the grape, tree-fruit, hardwood and nursery industries, which collectively are worth nearly $18 billion to the state’s economy. Homeowners also could sustain damage to high-value ornamentals in their landscape.

Native to China, India, Japan and Vietnam, the spotted lanternfly does not attack fruit or foliage. Rather, it uses its piercing-sucking mouthparts to feed on the woody parts of plants — such as tree trunks or branches and grape vines — where it excretes a substance known as honeydew and inflicts wounds that weep with sap. The honeydew and sap can attract other insects and provide a medium for growth of fungi, such as sooty mold, which covers leaf surfaces and can stunt growth. Plants with heavy infestations may not survive.

Said Tom Baker, distinguished professor of entomology and chemical ecology, who has 40 years of experience in entomology research, “The spotted lanternfly is the weirdest, most pernicious insect I’ve ever seen.”

Penn State researchers are attacking the problem on several fronts.

“After this pest was discovered in Pennsylvania in 2014, we began basic research to learn where it came from and to better understand its biology and behavior before we could start to develop tactics for managing it,” said Julie Urban, senior research associate in the Department of Entomology. “As a result, we have several ongoing projects that we hope will lead to practical solutions in the near future.”

Spotted lanternfly wingspan

Despite its colorful wings, the spotted lanternfly — one of a group of insects known as planthoppers — is a weak flyer but a strong and quick jumper.

Image: Pennsylvania Department of Agriculture


For instance, with support from the U.S. Department of Agriculture, Urban is studying the population genetics of spotted lanternfly in Pennsylvania. Identifying novel genetic markers and genotyping the insect can help in the effort to more precisely pinpoint the Asian origin of the lanternfly invasion and to geographically narrow the search for natural predators and parasitoids.

“Novel genetic markers that are variable within the Pennsylvania population also will help us estimate the effective size of the current population, enable us to track population growth and movement, and detect subsequent invasions,” she said.

Another line of inquiry, Urban said, is characterizing bacteria and fungi associated with spotted lanternfly. Using next-generation DNA sequencing, her team tested for the presence of bacterial and fungal communities in the lanternfly salivary glands and proboscis (mouthpart) and in abdominal tissue.

“We found that salivary gland and proboscis tissue did not harbor any detectable levels of bacteria or fungi. This means it’s unlikely that spotted lanternfly is transmitting bacterial or fungal pathogens to plants through feeding, although we are continuing to investigate potential transmission of other pathogens,” she said.

“In abdominal tissue, some bacteria present can differ depending on geographic range. Comparing the microbiome of the digestive tract of the Pennsylvania population with specimens from Asia may help us understand differences in host-plant preferences and feeding behavior, and we may find that Asian populations harbor bacteria that are natural pathogens of spotted lanternfly.”

Researchers also are monitoring the microbial communities on several economically important host plants to assess changes in composition and abundance of bacteria and fungi due to spotted lanternfly feeding and honeydew deposition. In addition, Urban’s team is examining the microbial communities present in a frothy substance found at the base of Ailanthus (tree-of-heaven) plants that show heavy lanternfly feeding damage and honeydew deposition.

Tree-of-heaven is one of the spotted lanternfly’s highly preferred host plants, and Urban said the froth will be analyzed to determine whether it serves as an attractant to the pest. “We will aim to determine the source of any potentially attractive compounds, which may be helpful in developing spotted lanternfly lures,” she said.

This work also may assist scientists in identifying beneficial bacteria that could help manage lanternfly-associated sooty mold by killing or out-competing the fungus, Urban explained.

Spotted lanternfly nymphs

The first three stages of immature spotted lanternflies are black with white spots. Fourth-instar nymphs, shown here, begin to appear in July and and will molt to become adults.

Image: Penn State Extension


Entomologist Baker has used funding from USDA’s Animal and Plant Health Inspection Service to study the mating and dispersal behaviors of spotted lanternfly. He noted that the use of insect pheromones for mating disruption has been deployed successfully for other insect pests.

“However, so far we have found no evidence that the spotted lanternfly uses pheromones to find mates, so that may not be something we can use for mating disruption or to develop lures or traps,” he said.

Baker’s laboratory has collected data on how spotted lanternflies disperse — how far they fly, what they orient to, what they land on and so forth. “Understanding the natural dispersal behavior could be helpful to state and federal agriculture officials and industry stakeholders in planning for where and in what direction the front edge of an infestation will spread,” he said.

In the short term, researchers are closing in on pesticide solutions that can help protect crops from spotted lanternfly damage. Erica Smyers, a doctoral candidate in entomology advised by Urban, has performed efficacy testing on several insecticides to gauge their potential for reducing populations of the pest. Dave Biddinger, research associate professor of entomology at Penn State’s Fruit Research and Extension Center in Biglerville, is helping to analyze the results.

Once data analysis is complete, scientists will seek an emergency exemption from the U.S. Environmental Protection Agency under Section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act to permit growers to use the most promising of these chemicals on certain crops.

In the meantime, Penn State entomologists are collaborating with other university and government scientists and seeking additional USDA grants to continue research on spotted lanternfly host-plant requirements, the development of biocontrols such as natural enemies, host-plant effects of sooty mold, and other topics related to this exotic and unusual pest.

More information about spotted lanternfly is available on the Penn State Extension website and on the Pennsylvania Department of Agriculture

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Public release: 30 Oct 2017


A newly developed technique can predict the risk of plant disease or infestation across the globe. Described in open-access journal Frontiers in Applied Mathematics and Statistics, the technique considers pest-host interactions and the geographical distribution of vulnerable plants to provide maps of potential disease hotspots. This could help governments to understand the risk of outbreaks before they happen.

Diseases and pests can have a devastating impact on plants, the surrounding ecosystem, and food supplies. These effects can be particularly damaging when a pest or pathogen invades a new territory, in which native plants have little natural resistance and the destructive invader has few native predators or competitors.

Government agencies try to restrict pests and pathogens by controlling the movement of plants and animals between countries and regions. However, with international trade and travel, it can be difficult or impossible to stop pests and pathogens from spreading.

One way to get a head start in preventing infection and infestation outbreaks is to analyze where known pests and pathogens are currently located, and then look at the distribution of plants that might be vulnerable to attack. However this type of in-depth analysis can be time-consuming, given the huge array of plant, pathogen and pest species.

To better help predict outbreaks, researchers in Mexico developed a new series of algorithms to help predict outbreaks. Their technique is based on the principle that closely related plants that grow near each other are prone to infection or infestation by the same pathogens or pests. By studying the geographical distribution of closely related plants, the research team generated maps of potential disease hotspots.

To test their algorithms, the team applied them to an invasive pest present in North America, the redbay ambrosia beetle. This invasive beetle transmits Laurel Wilt Disease, which can be deadly for plants of the laurel family. The researchers consulted online databases to find a group of ambrosia beetles that are closely related to the redbay ambrosia beetle, and a group of plant species that are associated with these beetles.

Using known beetle/plant interactions as a starting point, and then using their algorithms to estimate the probability that closely related plants would be similarly impacted, the researchers calculated the probability of each plant being affected by a particular beetle species.

The team then incorporated data about the known geographical distribution of each plant. If plants are found over large areas, then they are at higher risk for contracting and spreading an outbreak. Using their algorithms, the researchers calculated the probability of multiple plant species being infested by a beetle when the plants are present at the same site.

Using the technique, the team created maps showing regions of the world most likely to suffer infestation, or interaction between the beetles and plants. The maps accurately reflected the native territories of the beetles, along with the recent invasive behavior of some beetles, including the southward advance of one beetle across the United States. Worryingly, the model indicated that similar plants in Central and South America could be vulnerable to invasion next.

These types of maps could be very helpful for government agencies and ecologists in understanding and predicting outbreaks, by highlighting current or potential disease hotspots, but the team need further data from fieldwork to check the system’s accuracy.

However, these algorithms are not just applicable to plant infestations. “The method provides easy-to-use computer tools, which can be applied to understand and predict interactions between any group of organisms,” says Andrés Lira-Noriega, a researcher involved in the study.


This article is part of the Frontiers Research Topic “Data Mining and Methods for Early Detection, Horizon Scanning, Modelling, and Risk Assessment of Invasive Species”

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.Eureka



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Korea Herald

Fire ants found in Korea belong to American species: ministry

By Yonhap

  • Published : Oct 10, 2017 – 13:24
  • Updated : Oct 10, 2017 – 14:32
Red fire ants found in the southern port of Busan are presumed to be identical to a species in the United States, but further inspection is needed to figure out their exact origin, South Korea’s quarantine authority said Tuesday.

Twenty-five fire ants were discovered in a storage container at Busan’s Gamman port Sept. 28, and a nest capable of accommodating 1,000 was also found, raising alarm that the highly invasive insects were inadvertently brought into the country.

The Ministry of Agriculture, Food and Rural Affairs said it has conducted emergency quarantine measures and stepped up monitoring to prevent further spread, noting it did not find other ants in the 34 ports and two inland container depots examined so far.

Park Bong-gyun, the chief of the Animal and Plant Quarantine Agency, briefs on red ants at a government building in Sejong on Oct. 10, 2017. (Yonhap)

Although the remains of a queen ant were not found, the ministry tentatively concluded that it already died based on the size and scope of the colony discovered in the cracked asphalt.

“Red fire ants are generally found in the United States, but they have since spread to China, Australia and Japan, giving birth to special genetic variations as they evolve in their new environment,” Park Bong-gyun, the chief of the Animal and Plant Quarantine Agency, said in a briefing.

“It is premature to say the red fire ants came from the US at this point, as an in-depth epidemiological inspection into their variation is needed to figure out their origin.”

Gamman port received containers from six nations between May and September — China, Japan, Taiwan, the US, Australia and Malaysia — with 60 percent coming from China, the ministry said.

Quarantine officials will continue to sterilize the area within a 100-meter radius of the container depot until next week and conduct inspections on the pavement and other areas.

The ministry said it will work with other related organizations to regularly monitor and inspect major ports to prevent the inflow of red fire ants. (Yonhap)

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