Australia: Papaya mealybug confirmed in Northern Territory

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Wednesday, 26 July 2023 08:31:15

PestNet

Grahame Jackson posted a new submission ‘Papaya mealybug confirmed in Northern Territory’

Submission

Papaya mealybug confirmed in Northern Territory

Mirage News
https://www.miragenews.com/papaya-mealybug-confirmed-in-northern-territory-1050552/

The Department of Industry, Tourism and Trade has increased plant surveillance after a confirmed sample of the papaya mealybug was found in the Darwin region.

The suspected Paracoccus marginatus was discovered after the Plant Biosecurity team received a call from a concerned resident in Parap last week, who identified a cluster of white coloured insects on their papaya plants.

There are many species of mealybug including a native Australian species which can appear to be similar in appearance. To confirm whether the retrieved sample was Paracoccus marginatus, the insects were subject to further testing, which subsequently came back positive this week.

Additional surveillance has since identified infestations at residential properties in Parap, the Narrows and Winnellie.

The papaya mealybug appears as a cluster of white ‘cotton-like’ mass, usually found on the fruit or underside of the leaves of affected plants.

Although the papaya mealybug does not pose a threat to humans or animals, affected plants may appear deformed, wilted and the papaya fruit likely to remain hard and bitter, with the papaya, hibiscus and frangipani species particularly susceptible.

Surveillance and testing has been ramped up across the Top End. The Plant Biosecurity team will continue surveillance activities and the public is requested to not move suspected infected plants, plant cutting or fruit from their gardens.

The team will work closely with residents and industry during the surveillance period.

Residents of the Darwin region are advised to check plants on their properties and report anything unusual to the Exotic Plant Pest Hotline on 1800 084 881.

During this time, the public are requested to not take cuttings from plants such as hibiscus, frangipani and papaya and to refrain from purchasing plants from uncertified sources.

/Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.


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Aphids make tropical milkweed less inviting to monarch butterflies

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NEWS RELEASE 26-JUL-2023

EurekAlert

Peer-Reviewed Publication

UNIVERSITY OF FLORIDA

Many gardeners will tell you that aphids are the bane of their existence. According to a new study from the University of Florida, these tiny pests also pose problems for the iconic monarch butterfly. The study found that when oleander aphids infested tropical milkweed — a nonnative milkweed species commonly used across southern portions of the U.S. stretching from California to Florida — the butterflies laid fewer eggs on the plants, and caterpillars developing on those plants were slower to mature.

Monarch butterflies depend on milkweed and its close relatives to complete their life cycle. The study’s findings suggest that when aphids attack tropical milkweed, they compromise this monarch resource.

“Around the country, efforts are underway to plant milkweed in urban areas to support monarch populations. We know that aphids and similar insect pests commonly reach high densities on plants, including milkweed, in urban settings. Our study helps us better understand how such pest outbreaks may affect monarch survival on the most

common ornamental milkweed species produced and planted in the South,” said Adam Dale, senior author of the study and an associate professor in the UF/IFAS entomology and nematology department.

Throughout the southern U.S., tropical milkweed is commonly used both to attract and support monarchs and as an ornamental plant, and many nurseries and big box stories carry it. However, milkweed often harbors oleander aphids, a type of aphid that goes after oleander and milkweed plants. Oleander aphids suck the sap out of the plants, stunting them and leaving behind a moldy residue.

“It’s long been known that oleander aphids flock to milkweed, especially in nurseries and urban areas, and that led us to wonder if and how that affected the monarchs who used these plants,” said Bernie Mach, first author of the study and a postdoctoral researcher in the UF/IFAS entomology and nematology department.

While the study did not investigate exactly why aphid-infested plants are poorer hosts for monarchs, the scientists say that past research on how aphids affect tropical milkweed, combined with their findings, offers some clues.

“Milkweed defends itself against pests with chemical compounds in its sap called cardenolides — this chemical is actually what makes monarch butterflies toxic to certain predators,” Mach explained. “Tropical milkweed has particularly high levels of cardenolides that ramp up even more when it is attacked by large infestations of oleander aphids. We think that these ramped up levels may deter monarchs from laying eggs on these plants and also affect their caterpillars.”

However, one point is clear: Aphid-free tropical milkweed appears to give monarchs a better chance at success.

In the study, the researchers grew tropical milkweed in a nursery setting, introducing aphids to one group of plants while keeping another group aphid-free. The researchers released monarch butterflies around each group of plants, then counted the eggs the butterflies laid on the plants. The butterflies laid three times as many eggs on aphid-free plants as they did on aphid-infested plants.

The researchers also monitored the development of the caterpillars that hatched out of those eggs. At the end of the experiment, caterpillars on aphid-free plants ate twice as much leaf material as caterpillars on aphid-infested plants. All caterpillars on aphid-free plants grew to full size, while most of those on the aphid-infested plants lagged behind or died.

For home gardeners in the southern U.S. who want to conserve monarch butterflies through landscaping, the authors note that native milkweed species like swamp milkweed have lower cardenolide levels, and other research has shown that monarchs do well on these plants even when aphid levels are high. For those who want to use tropical milkweed as a way to help monarch butterflies, the researchers share a simple but effective way to control oleander aphids: insecticidal soap.

“Spraying the aphids directly with insecticidal soap — while avoiding monarch caterpillars and butterflies — is an effective way to keep oleander aphids down and help tropical milkweed stay in better shape,” Mach said.

However, insecticidal soap isn’t always a feasible option in a nursery where growers are trying to keep hundreds or thousands of plants aphid-free, Dale said. In the next phase of this research, Dale and Mach will investigate pest management options that keep aphids at low levels and aren’t harmful to monarch butterflies.


JOURNAL

PLoS ONE

ARTICLE PUBLICATION DATE

26-Jul-2023

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USDA Research Identifies Moths that Slow the Spread of Invasive Fern

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Southeast Asian fern-feeding larva or caterpillar. (Photo by John Goolsby, ARS)USDA Research Identifies Moths that Slow the Spread of Invasive FernFor media inquiries contact: Autumn Canaday, (202) 669-5480

July 27, 2023The invasive Old World Climbing Fern was introduced to Florida’s ecosystem from southeast Asia around 1965. It soon dominated the state’s native vegetation, infesting more than 100,000 acres in a short amount of time. The fern spreads quickly and has destroyed numerous native plant populations, smothering trees and shrubs with vines that can grow up to 90 feet in length. You’ll now find this invasive fern throughout south and central Florida, specifically in wetlands and other habitats like the Everglades tree islands, bald cypress domes, and sawgrass prairies.USDA-Agricultural Research Service (ARS) and the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australian Biological Control Laboratory (ABCL), scientists began to search for a way to solve this agricultural challenge and soon found an answer to slow the fern’s spread.ARS and ABCL researchers collected, identified, and tested caterpillars feeding on the Old World climbing fern in its native habitat. One species of fern-feeding snout moth, Neomusotima conspurcatalis, commonly known as the Brown lygodium moth,is a member of the subfamily of Musotiminae and has been a successful deterrent to this invasive fern.  The Musotiminae belongs to the Crambidae family that have protruding labial palpi, or “noses,” giving the family the common name of “snout moths.” Most of the moths that ARS researchers discovered in southeast Asia were snout moths, which at that time, belonged to a subfamily that had not been studied by the Agency.  “Early detection of potential invasive species is crucial so USDA can quickly implement strategies that protect U.S. agriculture, forestry, and the environment,” said ARS researcher Alma Solis. “This study led to the discovery of a number of new fern-feeding species and the identity of their caterpillars, which were previously unknown to science.”ARS researchers studied the snout moth’s external wing patterns, dissected its insides, specifically the genitalia and wings, and compared it to other southeast Asian moth species. All of the snout moth’s immature stages, including larvae, and pupae, had never been seen before and were considered new to science. The research team also compiled a chart to compare adult and immature morphologies, host plants, and geographic distribution of the fern-feeding species. The findings permitted ARS to create criteria for biological control workers across the globe to distinguish Musotiminae species in their own countries or eco-systems. The snout moth was later introduced to Florida and slowed the spread of the Old World Climbing Fern with their eating habits.ARS researchers, and research partners for the state of Florida, continue to study the interactions of snout moths with parasites, predators, and fungi. Together they are working together to deter the spread of this invasive fern throughout the nation and protect America’s native vegetation.The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact.

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The arms race between crop plants and fungal pathogens

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by Mia von Scheven, Max Planck Society

Blumeria graminis AVR effectors adopt a common structural scaffold. (A) Cartoon representation of the crystal structures of AVRA6, AVRA7, AVRA10, AVRA22, and AVRPM2. The effectors exhibit a canonical (α+β) RNase-like fold. (B) Disulfide bonds are conserved in Blumeria AVRs. AVRA6, AVRA7, AVRA10, AVRA22, and AVRPM2 form intramolecular disulfide bridges that connect the N and C termini. The disulfide bridge is indicated in the density map. (C) Amino acid sequences alignment of AVRA6, AVRA7, AVRA10, AVRA22, and AVRPM2 without signal peptides. Red background indicates amino acid similarity. The alignment was generated using ESPript 3.0 (46). (D) Maximum likelihood phylogeny including all predicted CSEPs from B. graminis f. sp. Poae, lolium, avenae, tritici 96224, hordei DH14, secalis S1459, triticale T1-20, and dactylidis. AVRA6, AVRA7, AVRA10, AVRA22, and AVRPM2 are widely separated in the phylogeny. (E) Superposition of AVRA6, AVRA7, AVRA10, AVRA22, and AVRPM2.. Credit: Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2307604120

Many cereal crops, such as wheat and barley, are prey to devastating fungal diseases caused by infection with so-called grass powdery mildews. A key battleground between the plants and the powdery mildews is the interaction between plant immune receptors and pathogen effectors, molecules which are delivered into host cells by pathogens to establish infection.

These effectors and immune receptors are locked in a molecular arms race in which the fungus needs to continuously adapt its effector repertoire to avoid recognition by adapted immune receptors and maintain virulence activity.

However, the structures and functions of these numerous effectors—which can run into the hundreds for individual fungal lineages—remain incompletely characterized.

Now, scientists from Germany, Switzerland and China led by Paul Schulze-Lefert, director at the Max Planck Institute for Plant Breeding Research in Cologne and Jijie Chai who holds positions at Westlake University, Hangzhou and Tsinghua University, both in China, have reported the structures of several powdery mildew effectors from different subfamilies.

These structures show how effectors adopt a common structural scaffold with some local variations that allow them to evade recognition by immune receptors. Their findings are published in the Proceedings of the National Academy of Sciences.

Using X-ray crystallography, a technique that allows scientists to deduce the positions of atoms in a molecule based on electron density, first authors Yu Cao and Florian Kümmel and colleagues acquired structures for five different effectors from two different powdery mildews that infect barley and wheat. Strikingly, although the similarity between the effectors was very low at the level of DNA sequence, they were all found to adopt a common structural fold, known as RALPH after RNase-like proteins associated with haustoria.

Analysis of these structures revealed that they are indeed similar to that of RNase proteins, enzymes that bind to, and break down RNA molecules. Intriguingly, however, these effectors do not possess any RNase activity. Instead, the authors suggest that this common fold RALPH framework may be important for critical processes related to infection, such as assembly into functional effectors and the ability to cross biological membranes. The local structural changes in the RALPH scaffold may explain why the effectors can associate with different host proteins to allow infection.

Armed with an understanding of the structural template of a RALPH effector, the researchers then set out to determine whether they could engineer recognition between immune receptors and effectors in instances where effector divergence had led to immune escape.

Strikingly, they found that six amino acid substitutions were sufficient to turn a sequence-diverged effector into one that was recognized by a specific immune receptor. Analysis of further effector-receptor pairs allowed the authors to conclude that each immune receptor detects largely distinct patches on the surface of its corresponding effector.

“It is one of the eureka moments of science when, in evolution, the molecular arms race between plants and pathogens can be explained by local structural changes within a shared three-dimensional protein architecture,” says Paul Schulze-Lefert.

More information: Yu Cao et al, Structural polymorphisms within a common powdery mildew effector scaffold as a driver of coevolution with cereal immune receptors, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2307604120

Journal information: Proceedings of the National Academy of Sciences 

Provided by Max Planck Society 


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Plants can skip the middlemen and directly recognize disease-causing fung

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Bees Look For a Balanced Diet

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ENTOMOLOGY TODAY  LEAVE A COMMENT

A study of managed bumble bees and honey bees on a blueberry farm finds that most of the pollen they collect comes from other plants, suggesting that supplementing crops with a diversity of nearby plant types makes for healthier bees. Shown here are honey bee hives near blueberry fields. (Photo by Kelsey Graham, Ph.D.)

By Andrew Porterfield

Managed bees provide a critical service to crop growers, providing pollination as the bees search for nectar and pollen for their own needs. But many crops cannot provide for all the nutritional needs of bees. In those cases, bees begin searching for alternative sources of food.

This means that beekeepers and farmers may need to find ways to provide alternate food sources for their bees—while the bees will still be attracted to crop pollen and nectar, it won’t be an exclusive relationship. But, in turn, the bees will likely be healthier. To find out how managed honey bees (Apis mellifera) and bumble bees (Bombus impatiens) seek out a balanced diet, a group of researchers from Michigan State University looked at pollination and feeding behavior of bees around blueberry crops in that state.

The team, led by Kelsey Graham, Ph.D., a research associate at Michigan State’s Entomology Department at the time of the study and now at the U.S. Department of Agriculture’s Agricultural Research Service, determined what plants managed honey bees and bumble bees visited during high bush blueberry pollination season. They found that the most pollen collected was from plants other than blueberries, even though the blueberry bushes were the most abundant resources during the study. They also found that honey bee and bumble bee collection behavior varied a lot. Their results were published in July in Environmental Entomology.

Overhead view of a white square bowl containing a few dozen small pollen balls, varying in color from dark yellowish brown to sandy brown to medium gray and dark gray.
A researcher in a white full-body beekeeping suit kneels by a low bumble-bee hive in a grassy area near a blueberry field, holding a sampling tube. In front of the researcher on top of the hive is a clipboard with a sheet of paper and a green tray with several small vials in rows.

In 2018 and 2019, the team collected pollen from bee colonies at 14 blueberry farms in Michigan. At each field, they used a 10-frame pollen trap immediately before the start of blueberry blooming (in early or mid-May) and collected samples through the end of the bloom (early to mid-June). At the same time, the researchers placed bumble bee colonies at the margin of each site, far enough away from the honey bee colonies to prevent raiding and robbing. The team used microscopes to identify the plant sources of the pollen.

Perhaps typical for them, bumble bees collected pollen from a wider range of plant species than did honey bees. Honey bees collected 21 pollen types in both 2018 and 2019. Bumble bees, however, collected 29 types in 2018 and 52 pollen types in 2019.

Surprisingly, common buckthorn (Rhamnus cathartica), an invasive species native to Europe and Asia, was one of the most abundant pollens collected by both types of bees. Willow (Salix spp.) was another. “Collection is likely from an invasive species in this area of Michigan, though there are some native species they could be visiting,” says Graham. “I think it surprises people to find out that blueberry pollen was not a dominant pollen collected by honey bees. While honey bees still provide pollination services for this crop through some pollen collection and nectar visits, it’s not a preferred pollen type.”

Microscope image of pollen grains from highbush blueberry. In the center of the image are two clumps of several round grains, purple in color. A scale bar indicates each clump is approximately 45 microns in diameter. Accompanying text reads "Vaccinium corymbosum (Blueberry cultivar), Highbush Blueberry, Michael Killewald, Isaacs Lab, Michigan State University, 2017, 400X."
Microscope image of pollen grains from common buckthorn. Toward the right of the image is a group of nine grains, purple in color and mostly triangular in shape with rounded corners. A tenth grain sits alone to the left. A scale bar indicates each grain is approximately 20 microns in diameter. Accompanying text reads "Rhamnus cathartica, Common Buckthorn, Michael Killewald, Isaacs Lab, Michigan State University, 400X, 2017."
Microscope image of pollen grains from black cherry. In the center of the image are six grains, purple in color and mostly triangular in shape with rounded corners. A scale bar indicates each grain is approximately 25 microns in diameter. Accompanying text reads "Prunus serotina, Black Cherry, Michael Killewald, Col. Tom Wood, Isaacs Lab, Michigan State University, 400X, 2017."

Although blueberry is a pollen-dependent crop that relies on managed and wild bees to yield fruit, blueberry pollen is not particularly nutritious for bees. Pollen provides proteins, fats, sterols, and micronutrients to support adult bee and brood health. However, the protein content of blueberry pollen is 13.9 percent, too low to sustain a healthy honey bee colony.

Therefore, bees will forage for other nutritional resources. Meanwhile, other studies have shown that a diversity of pollinators can improve pollination services for plants.

Graham and her team also studied whether landscape diversity influenced foraging behavior, but it appeared to have no effect on the diversity of pollen the bees collected. In other words, bees sought out a multitude of pollen types, even if they had to go further to find it. “This definitely suggests that honey bees and bumble bees are making foraging decisions based on floral characteristics and nutrition rather than just what they come across in the landscape,” Graham says.

The potential downside, though, to a predominantly crop landscape is that, as at least one other study has shown, the additional energy expended to collect pollen from other plants may reduce brood production.

“It’s somewhat rare that a single pollen source can fulfill all macro and micro nutritional requirements,” Graham says. “So, in landscapes where the crop is the primary plant available, supplemental plants through pollinator plantings or preserving natural habitats near farms can provide a large benefit to bees.”

Read More

Identity and diversity of pollens collected by two managed bee species while in blueberry fields for pollination

Environmental Entomology

Andrew Porterfield is a writer, editor, and communications consultant for academic institutions, companies, and nonprofits in the life sciences. He is based in Camarillo, California. Follow him on Twitter at @AMPorterfield or visit his Facebook page.

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 apis melliferabee foraging landscapeblueberryBombus impatiensbumble beesenvironmental entomologyforaginghoney beesKelsey Grahammanaged honey beesnectarpollenpollination

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Rise of the Spray Drone

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Sizes vary, but a sprayer drone can typically apply a 10′ to 40′ swath, depending on the wingspan, with bigger drones covering up to 50 acres an hour.(Bryan Young)

Squinting through the morning sun, Jesse Patrick watches the top of his corn crop whip in the downdraft of a large spray drone pipping fungicides into the canopy.“The drone is only putting out 2 gal. an acre, but the thing that surprised me was the swath and amount of downdraft coming off of it even flying 15′ above the corn,” Patrick recalls.This seventh-generation farmer, who grows soybeans, corn, wheat, hay and sorghum, is used to battling weeds and disease in his heavy Georgia clay soils about an hour east of Atlanta. Treating those yield robbers with a drone, however, is new.

“When the drone lands, you pull the battery out, fill it up, put in a new battery and the whole thing takes about 15 seconds,” Patrick says. “It’s a pretty well-oiled machine.”Rise-of-the-Spray-Drone-3Drone-driven sprayers are popping up across the country as better batteries, longer flight times and bigger machines make it possible to spray sizable acreage in a timely manner.“There’s a 10-gal. tank so every 5 acres he has to come back to refill,” Patrick explains. “We knocked out 150 acres in about four to six hours.”

Does it Work?

While farmers such as Patrick find the technology useful, especially for spot spraying and targeting fields in less-than-ideal conditions, weed scientists are buzzing with more caution.“We [weed scientists] are very sensitive about the resistance issue we have in weeds to herbicides, and as I’ve heard about using drones for applications, I wonder who’s testing it,” says Bryan Young, a weed scientist at Purdue University. “I wondered if we are going to generate more resistance, if this is a sub-optimal application, and I wasn’t getting a lot of answers.”That kick-started a research project into drone sprayers and verifying the new application method is effective enough to do the job. Young has witnessed the potential benefits of sprayer drones; however, as with all new technology, he’s still quantifying and investigating the results.Rise-of-the-Spray-Drone-5

“I was looking around for any guidelines on the best spray drone design in terms of nozzles and boom configuration,” Young says. “Frankly, to date, I can’t tell you where the industry is headed for sure or what is the best setup for herbicide application. This is an emerging technology for commercial applications in the U.S.”Drone operators often tout the strong down draft helping push product into the canopy, but then fly at higher elevations to maximize field coverage or spray swath. Young says these application methods are significantly different than traditional aerial applications, and it’s why he’s part of a working group looking into whether product labels should include separate drone application guidelines.“Right now, the U.S. EPA has left it up to each state to determine whether drones can be used for herbicide applications following the aerial component of the herbicide labels,” Young explains. “Not all states agree on that and not all countries agree.”Then there’s the question of drift. It’s still being investigated exactly how much different spraying with a drone is versus a ground-based sprayer or even by airplane.

Wind Tunnel Testing

“Underneath the drone’s propellers what would normally be a flat fan spraying from the nozzle, all of a sudden, [the pattern] starts to bend and oscillate,” explains Kyle Butz, a technical adviser with Spray Analytics.He’s been working with Sidaard Gunasekaran, a professor of mechanical and aerospace engineering at the University of Dayton, to test the effects of drone propellers on pesticide and herbicide application during flight. The two recently released their findings on droplet drift using the university’s low-speed wind tunnel.Rise-of-the-Spray-Drone-4“I think Kyle and I both asked the same question: On what basis are they deciding where to put the nozzles?” Gunasekaran recounts. “It turns out, they just take an agriculture nozzle, stick it underneath the propeller and then go fly without understanding the aerodynamics or the right location for that nozzle.”In search of answers, Gunasekaran and Butz developed a test rig with two propellers, a spray nozzle and a measurement system. They confirmed the propellers do in fact pull droplets back into the down draft while blowing smaller droplets out away from the target zone.“If you have smaller droplets, called fines, which are anything under 140 microns, they are prone to drift,” Gunasekaran says.From a sprayer’s perspective, however, there’s always been a balancing act between droplet sizes and efficacy.“Ultimately, spray applications come down to, one, droplets have to be large enough to safely reach the target, and two, they have to be small enough to work the way they’re supposed to be working,” Butz explains.Their recommendation is to start with products less likely to drift and use a drone in scenarios or situations that are less sensitive.Rise-of-the-Spray-Drone-2

A Tool Worth Trying

Like with all new technology, drone sprayers will no doubt have to earn their stripes. For farmers such as Patrick, it’s just another tool to deploy when the situation is right, such as when the aphids are going crazy on his sorghum but it just rained 2″ and he can’t run a sprayer.Today, he does not see this technology replacing the pre- or post-emerge passes on his operation.“However, at the end of the year, if you don’t want to run over a bunch of crops to spot spray, I think drone sprayers are definitely a tool we can use,” he says.“There’s a definite fit for these drones,” Young agrees. “It can allow us to be more timely with some of our pesticide applications and for us to be better stewards of pesticides.”

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Yemen: FAO trains farmers on alternative pest control and other best agricultural practices for FAW management

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Yemen: FAO trains farmers on alternative pest control and other best agricultural practices for FAW management

Format News and Press Release  Source

  Posted31 Aug 2023  Originally published31 Aug 2023  OriginView original

Farmers use a natural extract from local trees to manage the pest sustainably

It was a sad day when Ali Abdoul from Al-Buniyah, Yemen turned the leaf of his sorghum crop and saw a worm. This loathed pest is not just any worm, it is the so-called Fall armyworm that attacks many crops, with a clear preference for maize, and ruins livelihoods in a growing number of countries worldwide.

This pest made its way to the Taiz Governorate in July 2018, adding additional misery to Yemeni farmers, who were already grappling with a litany of challenges.

“For us farmers, pests are a menace as they devour crops…. In Yemen, pesticides are now very costly. We sometimes have to sell some crops from the previous harvest to get money to buy pesticides and save the current crop,” said Ali.

Many other farmers in Yemen share Ali’s sentiments. About 70 percent of Yemenis live in rural areas and depend heavily on agriculture as a critical source of food and income. The eight-year conflict in the country has worsened the situation and the prices of farming inputs have shot up.

In addition to rising input costs, farmers have faced a shortage of critical agricultural necessities such as seeds and fertilizer, a sharp increase in the price of fuel and unpredictable weather patterns.

And now they had Fall armyworm.

Ali describes how farmers were desperate to manage the new pest and tried different control methods without success. Home mixtures weren’t effective, and chemical pesticides caused harm to the environment and agricultural soils.

It was at this time when they were still struggling with the new pest that Ali, together with other farmers, started attending farmer field schools (FFS) organized by the Food and Agriculture Organization of the United Nations (FAO).

“Two agricultural officers from FAO came and taught us to concoct natural insecticides using the mraemrah tree,garlic and hot pepper. The training we got through the farmer field school included how to crush, grind and filter the impurities and then spray the mixture on the crops,” said Ali.

The mraemrah tree, also known as Melia azedarach, chinaberry tree or bead tree, is commonly found in Yemen. It produces chemicals that can serve as a natural insecticide, hampering the growth and development of the Fall armyworm. Not only is the tree available locally, the biopesticide can be prepared directly in villages and in small quantities.

This pest control method was a traditional practice, but they had never tried it on the Fall armyworm. Ali and his fellow farmers were astounded by the results.

“Using biopesticides extracted from mraemrah was something new to us. After spraying, we found that the results were excellent. We were impressed, and we resolved that going forward, we will continue using the pesticide extracted from the mraemrah tree to manage Fall armyworm,” said Ali.

Ali added that the farmers realized that using the mixture was much cheaper than using chemicals and that it had no environmental impact.

“This biopesticide is helping us in a huge way. We were also taught that this type of pesticide is not harmful to human and animal health,” added Ali.

These biopesticides are not only safer for human health and the environment, they are also safer for beneficial insects like bees and other pollinators.

Through the FFS, FAO was able to train farmers on these methods of alternative pest control and other best agricultural practices. This learning environment allows farmers to practice, test and evaluate new sustainable methods and technologies by comparing the results of the demonstration plots with their conventional ones.

In addition, the FFS approach has significantly strengthened the social cohesion among Yemeni farmers, especially in the conflict areas, by helping them decide together as a group a plan of action for their fields instead of each deciding individually.

The FAO project has also provided monitoring equipment (including pheromone traps used to attract pests to a specific location) and smartphones offering the FAMEWS mobile application to collect, record and transmit data gathered from pheromone traps. FAO trained technical staff on the use of the mobile application to help in scouting for and monitoring the pest.

Worldwide, FAO promotes an integrated pest management approach that minimizes reliance on chemical pesticides and incorporates sustainable practices, such as regular monitoring for pests.

With support from FAO, the national authorities in Yemen have since built the capacity to identify, monitor and manage Fall armyworm. FAO is rolling out this training and encouraging the use of biopesticides in other countries struggling with this pest.

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UK: First report of eggplant mottled dwarf virus

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UK: First report of eggplant mottled dwarf virus

Grahame Jackson/ PestNet

 Sydney NSW, Australia

 For your information

 10 days ago

EGGPLANT MOTTLED DWARF VIRUS – UK: FIRST REPORT

EGGPLANT MOTTLED DWARF VIRUS – UK: FIRST REPORT

A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org

Date: Mon 21 Aug 2023
Source: Springer via Journal of Plant Pathology [edited]
https://link.springer.com/article/10.1007/s42161-023-01483-1

Citation: Frew L, Hogan C, Andrews K, et al. First report of eggplant mottled dwarf virus in _Pittosporum tobria_ in the United Kingdom. J Plant Pathol. 2023; https://doi.org/10.1007/s42161-023-01483-1.
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In August 2020, a sample of _Pittosporum tobria_ was submitted to Fera Science Ltd. from a nursery in West Sussex, United Kingdom (UK). The sample was sent in during a routine plant health inspection, where the presence of an unknown disease was discovered on 20 plants. Symptoms included chlorotic mottling of veins and adjacent tissues along with the distortion of leaves. The sample was tested by high throughput sequencing (HTS) on a MinION sequencer (Oxford Nanopore Technologies) and nucleotide sequence analyses (GenBank Accession No. OQ716556). A total number of 178 904 read pairs were obtained, and eggplant mottled dwarf virus (EMDV) and pittosporum cryptic virus 1 (GenBank Accession No. OQ716558) were identified. The presence of EMDV was confirmed by ELISA using a specific antiserum (Loewe, Germany).

In February 2022, 2 _Pittosporum tobria_ were submitted to Fera Science Ltd. from a nursery in Gloucestershire, UK. Plants exhibited similar symptoms to those previously seen, and tested positive for EMDV by ELISA (DSMZ, Germany). EMDV and pittosporum cryptic virus 1 were confirmed by HTS using a MiSeq sequencer (Illumina UK) (Fowkes et al. 2021) (GenBank Accession No. OQ716555, OQ716557, OQ716559). In both instances, plants were destroyed on advice from DEFRA (Department of Environment, Food and Rural Affairs).

EMDV has been assigned to the species _Alphanucleorhabdovirus melongenae_ in the genus _Alphanucleorhabdovirus_, family Rhabdoviridae. It can spread through infected propagation material (De Stradis et al. 2008). EMDV can be transmitted by the leafhopper _Anaceratogallia ribauti_ (Giustina et al. 2000), and as this leafhopper is present in the UK, there is a possibility that this vector could be a source of the spread of the virus. Although the virus is highly damaging in vegetable crops, its impact remains minor because incidence in the field is very low. This is the 1st record of EMDV in the UK.


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ProMED

[A summary of EMDV is available at https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.20496. – Mod.JH

ProMED map of United Kingdom: https://promedmail.org/promed-post?place=8711796,40]

 ProMED

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Stink Bug Saliva: A Potent Mix to Bypass Plant Defenses

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Stink Bug Saliva: A Potent Mix to Bypass Plant Defenses

ENTOMOLOGY TODAY  1 COMMENT

The biochemical conflict between plants and the insects that eat them is vastly complex, as illustrated by new research identifying nearly 700 proteins in the saliva of just five stink bug species, many of which play potential roles in suppressing or deactivating plants’ own chemical defenses. The southern green stink bug (Nezara viridula), shown here, was one of the species included in the study. (Photo by Johnny N. Dell, Bugwood.org)

By Ed Ricciuti

Ed Ricciuti

Not long after insects appeared about 400 million years ago, some of them began eating plants, which in turn developed defenses against becoming food, triggering an evolutionary arms race. It’s a course without a finish line as, over time, plants evolve measures to protect against predation and insects come up with countermeasures that enable them to maintain their food supply. And so the cycle goes.

Morphology, such as the shape of insect mouthparts and plant spines, plays a role, but the main weapons in the conflict between insect and plant are biochemical, complex, and far from understood by science. One step toward understanding the complexities of chemical warfare in the insect-plant world is described in a new report about research on voracious, plant-eating stink bugs (Pentatomidae), published in July in the Annals of the Entomological Society of America.

In the study, researchers at the United States Department of Agriculture (USDA) and Washington State University (WSU) identified an astounding 677 proteins from the salivary glands of only five species of stink bugs that could be involved in suppression of plant defenses against predation. Past research on other insects suggests many of these proteins could suppress plant alarm systems that trigger defenses and could even deactivate the chemical molecules that make those defenses work. Plants defend themselves with weapons such as chemicals that kill or trap attackers, attract as allies natural enemies of herbivores, and changing insect behavior, and insects like stink bugs have intricate strategies in opposition.

The biochemical conflict between plants and the insects that eat them is vastly complex, as illustrated by new research identifying nearly 700 proteins in the saliva of just five stink bug species, many of which play potential roles in suppressing or deactivating plants' own chemical defenses. The brown marmorated stink bug (Halyomorpha halys), adults shown here, was one of the species included in the study. (Photo by Adrian T. Marshall, Ph.D.)

It may sound esoteric but the effort to understand the chemistry involved in the give-and-take between insect and plant has exceedingly practical implications. Why focus on stink bugs, though?

“Stink bugs encompass many species which are major pests of agricultural commodities including soybean, cotton, wheat, and tree fruits,” says Adrian T. Marshall, Ph.D., lead author of the study and a postdoctoral research associate at the USDA Agricultural Research Service and previously at WSU.

The research was conducted by analyzing ribonucleic acid (RNA) of stink bug salivary glands for the coded instructions necessary to manufacture various proteins. RNA not only carries the code for making proteins but also the amino acids that are the building blocks of these all-important, highly complex molecules.

Despite identifying several hundred proteins, untangling what they all do is tall task yet to be cleared. “We want to make clear that we can only guess their role based on previous literature,” Marshall says.

The study was sparked by the fact that stink bug damage is difficult to identify for growers and packing warehouses. “Data from the study can help future research start to piece out the individual functions of stink bug saliva in feeding,” Marshall says. “We hope this can be used to build tools for specifically identifying stink bug feeding damage through their excreted salivary enzymes.”

In a study of the proteins found in the saliva of stink bugs, Adrian T. Marshall Ph.D., and fellow researchers dissected specimens under microscopes to extract salivary glands for RNA sequencing and analysis. (Photo courtesy of Adrian T. Marshall, Ph.D.)
Microscope view of the head and antennae of a stink bug on a white background. At the base of the head is a tangle of whitish tissue.

Salivary proteins of many insects have various functions. The ability of some proteins to predigest plant food is well documented in several types of insect, including stink bugs. When feeding, they pierce a plant with tubular mouthparts, called a stylet, and through it inject saliva containing enzymes that liquefy and predigest tissue, which is then sucked in.

During feeding, these insects produce salivary secretions, some of which solidify around the stylet and are believed to aid feeding and suppress plant defenses. “Some interesting trends we saw is that [our analysis] included proteins for different types of stink bug feeding activities,” says Marshall.

Some of the proteins Marshall and colleagues describe seem to aid macerating and slurping in plant tissue. Others fight off microorganisms harmful to insects. Still others disrupt plant alarm systems that signal the presence of alien chemical molecules and activate defenses. Certain proteins, for example, deactivate the calcium ion Ca2+, which triggers the deposition of a compound called callose. It repairs wounds in the phloem when pierced by an herbivore’s stylus, curbing feeding.

The researchers say they hope this foundational work will spur future studies on stink bug biology and management.

“Beginning to examine and understand the ways they feed and interact with plant defenses can open new avenues for developing damage-identification tools and implementing control methods,” Marshall says. “The work can also begin laying the groundwork towards understanding other non-stink bug Hemipteran insect interactions with plants.”

Read More

Salivary protein expression profiles of five species of Pentatomidae (Hemiptera)

Annals of the Entomological Society of America

Ed Ricciuti is a journalist, author, and naturalist who has been writing for more than a half century. His latest book is called Bears in the Backyard: Big Animals, Sprawling Suburbs, and the New Urban Jungle (Countryman Press, June 2014). His assignments have taken him around the world. He specializes in nature, science, conservation issues, and law enforcement. A former curator at the New York Zoological Society, and now at the Wildlife Conservation Society, he may be the only man ever bitten by a coatimundi on Manhattan’s 57th Street.

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 Research News

 Annals of the Entomological Society of Americabrown marmorated stink bugEd RicciutiHalyomorpha halysNezara viridulaPentatomidaeplant defensessalivasouthern green stink bugstink bugsUSDA-ARS

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Finland: Fungal-plant symbiosis to boost crop resilience

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Finland: Fungal-plant symbiosis to boost crop resilience

NEWS RELEASE 28-AUG-2023

Peer-Reviewed Publication

UNIVERSITY OF TURKU

IMAGE: CABBAGE WHITE CATERPILLAR EATING AN OILSEED RAPE PLANT. view more CREDIT: BENJAMIN FUCHS, UNIVERSITY OF TURKU

Researchers inoculated oilseed rape plants with a species of fungus that is known for its ability to combat pest insects. Utilising the relationship between beneficial fungi and crop plants may introduce a new era of agriculture where the plant resilience is improved and the ecological footprint of traditional/chemical pesticides is minimised.

A study led by researchers from the University of Turku in Finland has shown that a species of fungus that normally grows in the wild and kills insects can be successfully inoculated in oilseed rape plants where it fosters a unique symbiotic relationship. The discovery is a step towards a future of sustainable agriculture, for which harnessing the power of beneficial fungi to enhance crop protection and productivity holds great potential.

The researchers used Beauveria bassiana, a species of fungus known for its ability to combat pest insects. It is commonly used as a biopesticide that is sprayed on the leaves of crops. These biopesticides are used around the world, but their weakness has been their vulnerability to UV degradation. This led the researchers to explore an alternative approach where they inoculated oilseed rape plants with the fungus to foster a unique symbiotic relationship.

“We embarked on a journey to unlock the potential of Beauveria bassiana in crop protection, while it might live endophytically within the plant tissue. This way, we aimed to create a natural defence mechanism against pests,” explains the first author of the study, Docent Anne Muola from the Biodiversity Unit of the University of Turku.

Successful symbiosis caused an increase in flavonoid biosynthesis

Researchers made a breakthrough by establishing an endophytic relationship between the fungus and oilseed plants. The growth of the fungus in the plant tissue triggered a remarkable increase in flavonoid biosynthesis and compounds known for multiple plant benefits including antioxidant properties.

“Our findings suggest that the interaction between the fungus and the plant spurred a positive response in the form of enhanced metabolite production, rather than a defence response against the fungal intruder,” states lead author of the study, Academy Research Fellow Benjamin Fuchs from the Biodiversity Unit of the University of Turku.

Flavonoids produced by the oilseed rape plant and renowned for their antioxidant properties and their role in UV protection, flower pigmentation, and herbivore deterrence, took centre stage in the study’s results.  Next, the researchers aim to find out how great of an impact this particular fungus has on plant resilience against environmental stressors and how it impacts crop quality.

Using microbes in agriculture can reduce reliance on chemical pesticides

“Our study holds immense promise for sustainable agriculture. By embracing the symbiosis between beneficial microbes and crop plants, we’re ushering in a new era of agricultural practices that reduce reliance on chemical pesticides,” says Fuchs.

According to the researchers, partnerships between organisms like the one unveiled in this study offer a glimpse into the future of agriculture where society strives to secure its food supply while minimising the ecological footprint.

“With the increasing recognition of the role of microbes in plant health and advanced biotechnological tools at hand, the stage is set for innovative approaches to optimise crop resilience and quality on a smart and sustainable path,” notes Fuchs.

The study is part of the EcoStack project in the EU’s Horizon Europe programme. The research article was published in the esteemed Pest Management Science journal.


JOURNAL

Pest Management Science

DOI

10.1002/ps.7672 

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