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BMA President Herman van Mellaert:

“We urge the EU to unleash power of biocontrol in support of Farm to Fork”

Europe’s biocontrol industry urges EU lawmakers to back biocontrol, or else miss the Green Deal targets. Reported pushbacks to make Farm to Fork objectives such as 50% reduction of chemical pesticides by 2030 ‘non-binding’ are of deep concern. The biocontrol industry instead recommends the European Commission to go further in its Farm to Fork ambition.

Speaking at the European Commission’s Farm to Fork Conference ‘Building Sustainable Food Systems together’, Jennifer Lewis, Executive Director of The International Biocontrol Manufacturers Association (IBMA), said: “The state of the climate, biodiversity, and health are of deep concern to us all and farmers need to be part of the solution. We need a profound food systems transformation in Europe with biocontrol in every farmers‘ toolbox.”

The Institute for European Environmental Policy report on biocontrol, published in June 2021, identified significant biodiversity, climate, and health benefits from biocontrol. Yet the biocontrol industry suffers from lengthy delays in the EU approval process under European pesticide regulation 1107/2009 which is designed for chemical pesticides and not for biologicals like micro-organisms, pheromones, or botanicals. Another crucial piece of EU legislation, the Directive on Sustainable Use of pesticides, still turns a blind eye to biocontrol.

“We have a full pipeline of natural solutions waiting to help produce sustainable food for all while cutting back rapidly on chemical pesticides. The revision of Sustainable Use Directive (SUD) is one of the first opportunities for the EU to translate Farm to Fork goals into policy. The SUD should be much firmer in promoting alternatives to chemical pesticides. The SUD should include an EU-wide definition of biocontrol as well as mechanisms to set targets for biocontrol, reward its use, and train users”, said Lewis.

IBMA President Herman van Mellaert added: “The revised SUD must take stock of the EU Green Deal and its Farm to Fork Strategy for which biocontrol is a key enabler. As passionate advocates of the Green Deal, the biocontrol industry cannot imagine that the EU Commission would even consider a SUD revision without a proper definition of biocontrol and strong mechanisms to give priority to our nature-based solutions. We urge the European Union to unleash the power of biocontrol in support of the Green Deal and Farm to Fork.”

Read the complete article here.

For more information:
International Biocontrol Manufacturers Association
www.ibma-global.org

Publication date: Wed 20 Oct 2021

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The Good Virus: A Bioinsecticide Helps Farmers Control Caterpillar Pests

10/19/2021 | 10:12 AM CDT

Progressive Farmer

Emily Unglesbee

By  Emily Unglesbee , DTN Staff ReporterConnect with Emily: @Emily_Unglesbee

Some farmers are taking advantage of a virus-based bioinsecticide that helps control Helicoverpa zea -- that multi-crop-eating pest known as corn earworm, cotton bollworm, soybean podworm and sorghum headworm. (DTN File Photo by Pamela Smith)
Some farmers are taking advantage of a virus-based bioinsecticide that helps control Helicoverpa zea — that multi-crop-eating pest known as corn earworm, cotton bollworm, soybean podworm and sorghum headworm. (DTN File Photo by Pamela Smith)

ROCKVILLE, Md. (DTN) — Frank Appleberry has a list of things to apply each spring to his crop fields in Tillar, Arkansas: preplant fertilizer, preemergence herbicides and oh, don’t forget the liquid blend of pulverized caterpillars, teeming with live viruses.

It sounds unconventional, but for a growing number of American farmers, this type of bioinsecticide is proving a regular and reliable tool to control Helicoverpa zea, the multi-crop pest known as soybean podworm, sorghum headworm, corn earworm and cotton bollworm.

These bioinsecticides are made from a strain of naturally occurring nuclear polyhedrosis viruses (NPVs), recently categorized as Group 31 insecticides. They are sprayed on row crop foliage like a normal insecticide. From there, things get a little gruesome, but only for the targeted caterpillar pests.

After ingesting the bioinsecticide, the caterpillar dies within a week, and the virus turns its corpse into a virus-replicating factory. The blackened, jelly-like remains of the worm overflow with more viruses, ready to infect more caterpillars, who in turn produce more virus. And so the cycle goes, until the caterpillar infestation abates and — without a host — the virus fades into the ecological background.

“It’s just part of what we do now in the spring,” explained Appleberry, who has replaced much of his onerous schedule of spraying soybeans at least every two weeks, with a single application of an NPV-based bioinsecticide called Heligen, around soybean bloom. “The first year we used it, we sprayed 1,150 acres and only had to come back with a pyrethroid for worms on about 200 acres,” he recalled.

These types of viruses are already circulating in nature and are not totally new to agriculture. University researchers dabbled with harnessing their insecticidal properties back in the 1970s, but they were largely supplanted by the advent of fast-acting synthetic insecticides, such as pyrethroids.

Now, a global biotech company, AgBiTech, has scaled up a commercial NPV product in the U.S., Heligen. It uses an NPV strain that targets H. zea (bollworm/earworm/podworm/headworm) and is registered for use in most row crops. AgBiTech also offers a suite of products registered globally to control other caterpillar pests, such as soybean looper (Chrysogen), armyworm (Fawligen), old world bollworm (Armigen), and a dual-virus product combining the H. zea and soybean looper strains (Surtivo). Other brands of NPVs also exist, but AgBiTech has made the largest inroads among American growers, university entomologists and farmers told DTN.

Amid growing insect resistance to insecticides and Bt, as well as interest in more eco-friendly farming practices, the success of NPVs has caught the attention of an even bigger player — Corteva Agriscience. This year, the company announced its plans to commercialize an NPV strain marketed under the brand name, Hearken, developed by a German company, Andermatt Biocontrol.

HARNESSING A FARMER-FRIENDLY VIRUS

AgBiTech prides itself on running what Chief Technology Officer Paula Marcon jokingly calls “a five-star hotel for caterpillars” at the company’s manufacturing facility in Fort Worth, Texas. No check-out required for these doomed guests, however, as the company infects the insects with their NPV strain of choice and then blends them into a smoothie-like liquid, ready for the sprayer.

“It’s a little brownish, like syrup and smells wonderful,” Marcon said. “And it’s well adapted to foliar applications.” Since the NPV cocktails contain living organisms, they do come with some special handling requirements. They can last many years in a freezer and several months at room temperature (under 77 degrees), but if they stay at temperatures well above 77 degrees for more than 36 hours, the products can start to break down. “That last mile to the field, you have to be careful,” said Marcon.

And since the viruses are protected by a protein coating that is degraded by highly alkaline environments — such as a caterpillar’s stomach — tank mixes need to stay below a pH of 8 to keep the virus alive, Marcon said. AgBiTech’s products, such as Heligen and Surtivo, can be tank mixed with other active ingredients, such as herbicides or fungicides, as long as the tank’s pH stays low enough, added Marcos Castro, AgBiTech’s vice president of sales and marketing.

Heligen requires a fairly low use rate, ranging from 1 to 2.5 ounces, depending on the crop, with costs landing around $5 to $6 per acre.

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Microscopic worms rescue cranberries

  • USDA Agricultural Research Service
  • Oct 19, 2021 Updated Oct 19, 2021

Tiny wormlike organisms called nematodes that attack cranberry pests could offer a natural alternative to using insecticides. 

  • Shawn Steffan

https://1f1e72bdfae6591b8600816cafd353b4.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.htmlhttps://1f1e72bdfae6591b8600816cafd353b4.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.htmlTownNews.com Content Exchange

Nematodes with a taste for “insect innards” may offer cranberry growers a natural alternative to fighting hungry crop pests with chemical insecticides.

Scientists with the U.S. Department of Agriculture’s Agricultural Research Service and University of Wisconsin are now exploring the possibility in field trials.

They’ve set their sights on redheaded flea beetles, Sparganothis fruitworms and other cranberry pests that attack the cranberry plant itself or its tart-tasting fruit. Severe infestations can force growers to apply insecticides, ratcheting up their production costs. Developing alternative controls as part of an integrated pest management approach can reduce or replace the need for insecticides, said Shawn Steffan, an entomologist with the Agricultural Research Service Vegetable Crops Research Unit in Madison, Wisconsin.https://1f1e72bdfae6591b8600816cafd353b4.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

For his part, he and UW collaborator Shane Foye are working to formulate a bio-insecticide that’s made of entomopathogenic — “insect-killing” — nematodes. One species they’re particularly excited about came from the self-same environment that cranberries thrive in — the marshland and bogs of central Wisconsin. Cranberry also happens to be the official fruit of the state, which produces 60 percent of the nation’s total crop.

Annually Americans consume 2.3 pounds of cranberries per person, primarily as juice but also in dried fruit snacks and holiday fare such as cranberry relish. However the path from bog to juice bottle can be a perilous one — no thanks to sundry insect pests whose appetites for destruction threaten the crop’s yield, fruit quality or both.

Nature, though, has seen fit to make the pests a favorite food of the nematodes Heterorhabditis georgiana and Oscheius onirici. Both species were found in the acidic wet bogs of central Wisconsin. Interestingly H. georgiana was originally discovered by David Shapiro-Ilan, who is another Agricultural Research Service scientist, in Georgia.

Steffan said, “O. onirici was originally found within caves in Italy, but clearly there are populations making a living in the marshlands of Wisconsin.”

The researchers hope both nematode species will prove to be an especially useful ally to both conventional and organic cranberry growers. Neither species is a threat to people, pets or other vertebrate animals. But what they do to their preferred prey isn’t pretty. After entering a natural body cavity, the nematodes release symbiotic bacteria that liquefy their prey’s internal organs and tissues. That creates a nutritious soup that the nematodes eat. Afterward they mate and deposit eggs inside their host’s remains. Eventually juvenile nematodes wriggle free in search of new hosts to infect, a cycle that lasts as long as their prey does.https://1f1e72bdfae6591b8600816cafd353b4.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

In field trials, spraying a solution of the nematodes onto cranberry beds reduced flea beetle numbers by as much as 93 percent. Average levels of control typically reached 60 percent to 70 percent — equal to two insecticide applications, Steffan said. In related laboratory experiments, O. onirici also proved lethal to the adult and larval stages of the spotted wing drosophila, an invasive species from Asia that’s become an established U.S. pest of many different fruit crops.

Encouraged by the results, the researchers have devised a method of rearing the nematodes by the billions and creating a clean highly concentrated mass of them that can be mixed with water and sprayed onto cranberry plants

“(And) we are trying some side-by-side trials this year involving commercial nematodes,” Steffan said. “This will give us some idea as to how our native Wisconsin nematodes compare to ‘off-the-shelf’ varieties.”

Thank you for reading kmaland.comAt KMA, we attempt to be accurate in our reporting. If you see a typo or mistake in a story, please contact us by emailing kmaradio@kmaland.com.

This article originally ran on agupdate.com.

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Benefits to Using Barn Owls for Rodent Control

Barn owls are big, beautiful biocontrol.By Stacie Clary -October 7, 20210485

Like any biocontrol option, barn owls won’t drive pest populations to zero and may need to be augmented with rodenticides occasionally (all photos courtesy Ryan Bourbour.)

Barn owls are rodent-killing machines,” said Sara Kross, a lecturer at Columbia University, “They are natural predators of gophers and voles, which can be really horrible pests for agriculture.”

For farmers, ranchers and/or land managers facing serious rodent problems, encouraging native barn owls to nest on their land can provide effective, ongoing biocontrol. The Western Sustainable Agriculture Research and Education (SARE) program has funded multiple research projects, such as one by Kross, looking at how to incorporate barn owls into a broader integrated pest management system. From this research, the program has developed a four-page “How To Guide” with tips for welcoming in barn owls to provide rodent control.

The Research

Barn owls are effective biocontrol against rodents, but like any biocontrol option, they won’t drive pest populations to zero and may need to be augmented with rodenticides occasionally.

Kross’ study looked at the frequency and level owls on farms are being exposed to rodenticides through analysis of their pellets, droppings and blood. The team looked for the effects of that rodenticide exposure on the owls.

One farm where the team has been conducting its research is Matchbook Wine Company’s vineyards in the Dunnigan Hills north of Sacramento.

“My family’s been growing wine grapes here since the 1970s, and controlling rodents is a big part of our integrated pest management program,” said Matchbook’s Greg Giguiere.

“We have 40 owl boxes on the farm. The rodent control is what we’re after, and it’s part of having an integrated system of biodiversity and biological controls to complement the chemical options we have for controlling these types of things.”

Another aspect of the project is tracking where the owls hunt. For that, adults were fitted with little GPS backpacks that recorded their movements for up to two weeks at a time before the backpacks were transferred to a different bird to record more data.

“Barn owls are an excellent study species because they come back to sleep in these boxes during the day, so we can safely recapture them,” says Ryan Bourbour, a Ph.D. student at UC Davis who is tracking the owls.

The study data is helping growers place barn owl boxes in the locations that will do them the most good and place rodenticide bait stations in the periods and places that cause the owls the least harm.

And that is very attractive to Giguiere.

“A big part of farming is being connected to the land,” he said. “So, a lot of what we do goes to that. I’ve been very interested in reducing chemical inputs into our system and moving away from a monoculture and having more biodiversity. So, it’s a very exciting program and we’re definitely on board and moving forward, and want to do even more habitats for hawks and other predators.”

Providing barn owls with artificial nest boxes on your farm and ranch helps them because natural nest sites are often a limiting factor for barn owl populations.

Are Barn Owls Right for Your Operation?

Barn owls can help keep rodent populations under control and deter rodent damage to fields, irrigation lines and equipment. As night-hunters, they’re effective at controlling mice, gophers and voles. Their boxes can also serve as hunting platforms for day-hunters like hawks, kestrels and eagles, which can help control and deter ground squirrel populations. In addition, there’s often great satisfaction knowing you’re hosting and helping these gorgeous natural predators.

If you have a serious rodent problem in your fields, barn owls can help. Providing barn owls with artificial nest boxes on your farm and ranch helps them because natural nest sites are often a limiting factor for barn owl populations.

During the mating and nesting season, barn owls are looking for a safe place to raise their young and a lot of rodents to feed them. If you already have the rodents, you just need to add owl boxes to house the barn owls.

For even better rodent control, also install raptor perches when you install barn owl boxes. Mount a wooden cross brace to a 10- to 15-foot-high pole. Hawks and kestrels will use them while hunting during the day, and barn owls use them at night.

Developed from this research, Western SARE’s free How-To Guide (western.sare.org/resources/welcome-in-barn-owls-to-provide-rodent-control/) takes you through decision-making, provides tips on how to provide nest boxes and describes how to site and maintain the boxes as well as how to determine if they are working.
Western SARE has developed multiple research-based How-To Guides for farmers and ranchers that can be downloaded for free at western.sare.org/learning-and-resources/how-to-quick-guides/.

For farmers, ranchers and/or land managers facing serious rodent problems, encouraging native barn owls to nest on their land can provide effective, ongoing biocontrol.

Read Full Post »

Benefits to Using Barn Owls for Rodent Control

Barn owls are big, beautiful biocontrol.By Stacie Clary -October 7, 20210338

Like any biocontrol option, barn owls won’t drive pest populations to zero and may need to be augmented with rodenticides occasionally (all photos courtesy Ryan Bourbour.)

Barn owls are rodent-killing machines,” said Sara Kross, a lecturer at Columbia University, “They are natural predators of gophers and voles, which can be really horrible pests for agriculture.”

For farmers, ranchers and/or land managers facing serious rodent problems, encouraging native barn owls to nest on their land can provide effective, ongoing biocontrol. The Western Sustainable Agriculture Research and Education (SARE) program has funded multiple research projects, such as one by Kross, looking at how to incorporate barn owls into a broader integrated pest management system. From this research, the program has developed a four-page “How To Guide” with tips for welcoming in barn owls to provide rodent control.

The Research

Barn owls are effective biocontrol against rodents, but like any biocontrol option, they won’t drive pest populations to zero and may need to be augmented with rodenticides occasionally.

Kross’ study looked at the frequency and level owls on farms are being exposed to rodenticides through analysis of their pellets, droppings and blood. The team looked for the effects of that rodenticide exposure on the owls.

One farm where the team has been conducting its research is Matchbook Wine Company’s vineyards in the Dunnigan Hills north of Sacramento.

“My family’s been growing wine grapes here since the 1970s, and controlling rodents is a big part of our integrated pest management program,” said Matchbook’s Greg Giguiere.

“We have 40 owl boxes on the farm. The rodent control is what we’re after, and it’s part of having an integrated system of biodiversity and biological controls to complement the chemical options we have for controlling these types of things.”

Another aspect of the project is tracking where the owls hunt. For that, adults were fitted with little GPS backpacks that recorded their movements for up to two weeks at a time before the backpacks were transferred to a different bird to record more data.

“Barn owls are an excellent study species because they come back to sleep in these boxes during the day, so we can safely recapture them,” says Ryan Bourbour, a Ph.D. student at UC Davis who is tracking the owls.

The study data is helping growers place barn owl boxes in the locations that will do them the most good and place rodenticide bait stations in the periods and places that cause the owls the least harm.

And that is very attractive to Giguiere.

“A big part of farming is being connected to the land,” he said. “So, a lot of what we do goes to that. I’ve been very interested in reducing chemical inputs into our system and moving away from a monoculture and having more biodiversity. So, it’s a very exciting program and we’re definitely on board and moving forward, and want to do even more habitats for hawks and other predators.”

Providing barn owls with artificial nest boxes on your farm and ranch helps them because natural nest sites are often a limiting factor for barn owl populations.

Are Barn Owls Right for Your Operation?

Barn owls can help keep rodent populations under control and deter rodent damage to fields, irrigation lines and equipment. As night-hunters, they’re effective at controlling mice, gophers and voles. Their boxes can also serve as hunting platforms for day-hunters like hawks, kestrels and eagles, which can help control and deter ground squirrel populations. In addition, there’s often great satisfaction knowing you’re hosting and helping these gorgeous natural predators.

If you have a serious rodent problem in your fields, barn owls can help. Providing barn owls with artificial nest boxes on your farm and ranch helps them because natural nest sites are often a limiting factor for barn owl populations.

During the mating and nesting season, barn owls are looking for a safe place to raise their young and a lot of rodents to feed them. If you already have the rodents, you just need to add owl boxes to house the barn owls.

For even better rodent control, also install raptor perches when you install barn owl boxes. Mount a wooden cross brace to a 10- to 15-foot-high pole. Hawks and kestrels will use them while hunting during the day, and barn owls use them at night.

Developed from this research, Western SARE’s free How-To Guide (western.sare.org/resources/welcome-in-barn-owls-to-provide-rodent-control/) takes you through decision-making, provides tips on how to provide nest boxes and describes how to site and maintain the boxes as well as how to determine if they are working.
Western SARE has developed multiple research-based How-To Guides for farmers and ranchers that can be downloaded for free at western.sare.org/learning-and-resources/how-to-quick-guides/.

For farmers, ranchers and/or land managers facing serious rodent problems, encouraging native barn owls to nest on their land can provide effective, ongoing biocontrol.

Read Full Post »

Where there’s a weevil, there’s a way to end giant weed problem

Durie Rainer Fong -October 7, 2021 3:16 PM16Sharesfacebook sharing button 11

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Sabah’s Lake Tungog is covered with salvinia molesta. The giant weed can destroy freshwater fish species, submerged aquatic plants and deoxygenate the water. (Sabah Foresty Department pic)

KOTA KINABALU: Sabah is introducing a beetle species to its lakes and rivers in the hope of clearing them of the salvinia molesta, a type of an invasive aquatic plant.

Chief minister Hajiji Noor lauded the introduction of the Cyrtobagous salviniae weevils, by the state agriculture and fisheries ministry as an environmental-friendly effort to check the Salvinia molesta – or giant salvinia – infestations statewide.

Weevils are beetles that are often considered pests because of their ability to kill crops.

Speaking during the launching of a programme to introduce the bugs to all Sabah districts today, Hajiji said the giant salvinia weeds have infested at least 200 bodies of water such as rivers, waterways, fish ponds and padi fields throughout the state.

“This is a serious situation and has to be addressed immediately,” he said in a statement here.

He added that steps have to be taken to stop the spread of the weed in Kinabatangan, Sandakan, Lahad Datu, Tawau, Semporna, Beaufort, Kuala Penyu, Papar, Kota Kinabalu, Penampang, Kota Marudu, Kota Belud, Kudat, Tongod and Tuaran.

The Cyrtobagous salviniae weevils which feed on the giant weeds. (Wikipedia pic)

Native to Brazil, the Salvinia molesta grows on water surfaces and endangers biodiversity and freshwater species, including fish and submerged aquatic plants.

The weed was first sighted in Sabah in early 2000s.

While it has the potential to treat blackwater effluent for an environmentally friendly sewage system, its rapid growth clogs waterways and blocks sunlight needed by other aquatic plants, particularly algae, to perform photosynthesis.

On the other hand, the weevil is a biological pest control agent for the giant salvinia, or kariba weed, since both adults and larvae feed on the plant.

Hajiji said the state government fully supported the various steps taken by the Sabah agriculture department together with various agencies in monitoring the giant salvinia infestation.

“I call upon the people of Sabah to join in and help keep our bodies of water and environment pristine,” he said.

At the same time, Hajiji said the people must refrain from bringing in, selling or spreading any type of non-native plant, animal or microorganisms without going through the proper quarantine procedures as stipulated in the 1976 Plant Quarantine Act and 1981 Quarantine Regulations.

Chief minister Hajiji Noor (second right) receiving pamphlets on the cyrtobagous salviniae weevils from Sabah agriculture director Dzulkifli Ghulamdin in Kota Kinabalu today. (CM Dept pic)

Giant salvinia can be bought online as decoration for guppy fish aquariums.

Meanwhile, in a separate statement, deputy chief minister Jeffrey Kitingan said the giant salvinia is only one of more than 100 invasive alien species (IAS) in Sabah currently.

“The programme today is in accordance with the recommendations of the Convention on Biological Diversity (CBD) which is an international multilateral treaty under the United Nations (UN).

“This convention has been refined and translated into the Sabah Biodiversity Strategy 2012-2022 and the National Biodiversity Policy 2016-2025 policies,” he said.

Kitingan, who is also the state agriculture and fisheries minister, said one of the activities and targets outlined in the existing policies is the control of IAS.

He said Malaysia has also previously encountered invasive foreign species, such as the cocoa pod borer insect which was a pest of cocoa crops in the 1980s and also the golden apple snail which was a pest in rice fields in the 1990s.

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Back-Seat Driver: The Parasite That Makes Bees Drop Off Its Babies

ENTOMOLOGY TODAY3 COMMENTS

Halictoxenos borealis, a species of strepsipteran, or twisted-wing insect, that parasitizes the bee Lasioglossum apristum affects the bee’s flower-visiting behavior. When the parasitize bee, as shown here, visits a hydrangea flower, it curls its abdomen and presses it against the leaf—making it easier for the parasites to offload their larvae. (Rather than laying eggs, H. borealis females release first instar larvae.) (Photo originally published in Nakase and Kato 2021, Journal of Insect Science)

By Paige Embry

Paige Embry

From a human perspective, insects are odd, odd creatures. Some display the wonder of complete metamorphosis, allowing us to simultaneously love nectar-sipping butterflies and fret over their leaf-eating caterpillar offspring. We marvel at strange or seemingly impossible ways of life: dung-rolling beetles, reproduction with no males required, death by sex for honey bee males. And near the apex of oddness are the strepsipterans, aka the twisted-wing insects.

Strepsipterans parasitize a wide array of other insects. The males are free-flying but the females of many species achieve independent mobility only as first instar larvae—which is when they seek out a host to live within for the rest of their lives. The females don’t develop into “typical” adult insects—they have no wings, no legs, no eyes—but they are fertile and manage to mate even though they live inside another insect. These females have a brood canal (also the mating portal) and they stick the body part that has that canal outside the host and release a pheromone, calling the males to them. Adult males live for only a few hours, and that time is all about finding and mating with one of those protruding body parts. A new study published in the Journal of Insect Science shows that at least one species of strepsipteran, Halictoxenos borealis, also seems to have a super-power—mind-control of its host insect.

strepsipteran parasite on bee abdomen
strepsipteran parasite larvae emerging

The study looked at the behavior of Lasioglossum apristum, a bee parasitized by Halictoxenos borealis. Yuta Nakase, Ph.D., a postdoctoral researcher at Shinshu University in Nagano, Japan, says he chose this project after seeing parasitized L. apristum visiting hydrangeas, which have no nectar and therefore provide only pollen rewards for visiting bees. Since adult female bees usually collect pollen to feed offspring and not themselves, Nakase realized this behavior didn’t make sense, because one of the side effects of being parasitized by H. borealis is that L. apristum have no offspring.

Yuta Nakase, Ph.D., a postdoctoral researcher at Shinshu University in Nagano, Japan, studied Halictoxenos borealis after seeing the peculiar behavior of the Lasioglossum apristum bees that it parasitized. (Photo courtesy of Yuta Nakase, Ph.D.)

“I had a hunch that something strange would be happening and decided to do some research,” says Nakase.

Nakase and colleague Makoto Kato, Ph.D., of Kyoto University, developed a study to try and determine if H. borealis affected the behavior of the L. apristum bees not merely by their presence but via active manipulation of the host’s behavior—or, put another way, mind control.

The scientists studied the actions of parasitized and unparasitized L. apristum bees on Hydrangea serrata. They found both kinds of bees walked around, neither bothered to look for nectar, and neither ate any pollen (none was found in their guts). But the behavior of the two types of bees differed in one significant way: Unparasitized bees actively collected pollen to take home to their larvae, while the parasitized bees collected none. Instead, a parasitized bee curled its abdomen and pressed the top against the leaf—making it easier for the parasites to offload their larvae. (Rather than laying eggs, H. borealis females release first instar larvae.) Unparasitized bees did not engage in this activity.

The researchers say that this behavior was “evidence that strepsipteran parasites can alter the behavior of individual bees by changing their flower-visiting objective and corresponding behavior from pollen collection to the release of first instar larvae.”

Nakase says that he’d like people to know more about the importance of parasites. “From the perspective of biodiversity conservation and agricultural productivity, it is important to understand the parasites are involved in the pollination symbiosis system, but we do not know enough about them,” he says.

Parasites may have a bad reputation, and a lot of people might be happy if parasites disappeared from the world, but Nakase isn’t among them—even regarding the parasites that engage in mind control.

Read More

Bee-Parasitic Strepsipterans (Strepsiptera: Stylopidae) Induce Their Hosts’ Flower-Visiting Behavior Change

Journal of Insect Science

Paige Embry is a freelance science writer based in Seattle and author of Our Native Bees: North America’s Endangered Pollinators and the Fight to Save Them. Website: www.paigeembry.com.

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New mechanism of parasitoid wasps in avoiding intraspecific competition

Zhejiang University

Parasitic wasps are natural enemies for effective control over the population of pests in nature. Hence, they are extensively used as green agents of pest control in agriculture and forestry. There are a diversity of parasitic wasps, which have assorted parasitic habits. In general, parasitism can be divided into three types: solitary parasitism, gregarious parasitism and synparasitism. Superparasitism-two or more eggs being laid into a single host by one or more parasitoid females-usually leads to intraspecific or interspecific competition, which is thus a waste of parasitic resource. Superparasitism avoidance has captured immense attention among biologists both at home and abroad, but the underlying mechanism remains obscure.

The team led by Prof. CHEN Xuexin and Prof. HUANG Jianhua from the Zhejiang University College of Agriculture and Biotechnology worked in partnership with the team led by researcher ZHAN Shuai from the CAS Center for Excellence in Molecular Plant Sciences to conduct research into how parasitic wasps manipulate their host behavior to avoid intraspecific competition. Their research findings were published in an article titled “Neofunctionalization of an ancient domain allows parasites to avoid intraspecific competition by manipulating host behaviour” in the journal Nature Communications on September 16.

The proposed evolutionary scenario of superparasitism avoidance in Leptopilina

Leptopilina genus has some important parasitoid wasps of soft fruit pests, including some Drosophila species. Researchers discovered that two closely related species of Leptopilina-L. boulardi and L. heterotoma-are characterized by superparasitism avoidance. Therefore, these two parasitic systems are the ideal model for exploring the avoidance of intraspecific competition among parasitoid wasps. They first found that Leptopilina parasitism is often accompanied by the host escape response. By comparing escaped and non-escaped hosts, they detected noticeable superparasitism among non-escaped, i.e. they often had multiple parasitic eggs in their bodies, suggesting that host escape is a strategy that helps parasitoid wasps avoid intraspecific competition. It was further found that all escaped hosts had eggs laid and venom protein injected by the parasitoid wasps. By combining multi-omics data, researchers characterized a small set of RhoGAP genes (termed as Escape-related genes with a GtPase Activating Protein domain-EsGAP) that mediate the parasite’s manipulation of host escape by inducing reactive oxygen species in the host central nervous system. Functional studies revealed that this family of proteins can cause elevated levels of reactive oxygen species (ROS) in the central nervous system of the host larvae, thereby leading to the host escape behavior. The study finally traced the origin and evolution of such EsGAP genes and found that the RhoGAP structural domain, which is pervasive in eukaryotes, has evolved in a large number of independent replication events, and one of its branches is recruited and eventually specialized into a venom gland-specific expression gene by Leptopilina, fulfilling a new function in regulating host behavior.

“We have identified a parasitic strategy of Leptopilina in regulating host behavior, thus avoiding intraspecific competition and elucidating the involvement of EsGAP in manipulating host escape behavior at the molecular level,” said Prof. Chen. “We have also proposed a new theory regarding how avoidance of superparasitism and intraspecific competition promotes population differentiation and host expansion among parasitoid wasps. These research findings contribute to a perspicacious understanding of the molecular mechanism of superparasitism avoidance in parasitoid wasps and provide a theoretical basis for enhancing the potential effect of parasitoid wasps in biological control.”

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Ava-Asaja demands drastic measures to prevent the advance of the insect

Trioza erytreae, the vector that transmits HLB, arrives in the Portuguese Algarve

The Valencian Association of Farmers (Ava-Asaja) demands that the Spanish Government and the European Union (EU) assess and implement drastic measures to prevent the advance of the Trioza erytreae insect, the vector of the Huanglongbing (HLB) disease -the most devastating disease for citrus in the world that is known as citrus greening or yellow dragon disease- after learning that this insect had already reached Algarve, in southern Portugal. This insect’s advance from the north and center of the Portuguese country to the citrus fruits of the Algarve increases the possibility that this transmitting vector and the HLB bacteria will reach the citrus farms of Huelva and the rest of Spain and Europe.


Female Trioza erytreae.

Ava-Asaja urged authorities to take all the scientific actions possible to stop the spread of this plague or, at least, to slow down the speed of its geographical progression. The agrarian organization highlighted an ambitious plan endowed with community funds aimed at promoting lines of research, breeding, and carrying out a massive release of highly effective parasitoids against HLB transmitting vectors.

In this regard, the Tamarixia drii predator has managed to reduce the presence of Trioza erytreae by more than 90% in the citrus farms investigated in the Canary Islands. Meanwhile, there are international studies on parasitoids that could also combat the other HLB vector, Diaphorina citri, which is even better adapted to the Mediterranean climate.

In the event that the bacteria arrive, the association urges the exploration of stronger complementary measures such as cutting down infested trees because, just as with Xylella fastidiosa, there still is no cure for this disease that has caused unaffordable losses for citrus growers and the uprooting of trees in the countries it has affected. Finally, Ava-Asaja asked the Spanish Government to work hand in hand with the Portuguese executive so that they are informed of the evolution of the situation and can act in the most coordinated and forceful way possible.

“The terrible news we’ve received about the HLB vector is further proof of the little seriousness and rigor with which the European Commission toys with agricultural pests and diseases. In recent years, they have been unable to prevent the entry and expansion of many pests and diseases coming via imports from third countries, such as Xylella fastidiosa, South African cotonet, or the almond wasp. Now we are facing the worst threat to the world’s citrus industry. In the absence of curative solutions, the best medicine for HLB is prevention. However, that may not be enough so we might have to take stronger measures,” stated the president of Ava-Asaja, Cristobal Aguado.

For more information:

Ava-Asaja
Tel.: +34 963 804 606
info@avaasaja.org
www.avaasaja.org

Publication date: Mon 4 Oct 2021

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Fungal transplants from close relatives help endangered plants fight off disease

by American Phytopathological Society

Fungal transplants from close relatives help endangered plants fight off disease
Myrtle rust on the leaves of Eugenia koolauensis, a critically endangered endemic Hawaiian tree. Credit: M. K. Chock

For the endangered Hawaiian plant Eugenia koolauensis, fungi could be both its demise and its savior. The fungal pathogen myrtle rust (Austropuccinia psidii) has been devastating populations of the endemic tree, along with many other native and cultivated plants. However, researcher Mason Kamalani Chock thinks part of the solution might be more fungi.

Endophytic fungi, which reside inside leaves, often protect plants from pathogens. In a paper recently published in Phytobiomes Journal, Chock, along with fellow University of Hawaii researchers Benjamin Hoyt and Anthony Amend, treated E. koolauensis plants with endophytic fungi isolated from the leaves of closely related plant species, then assessed the resistance of these inoculated plants against myrtle rust. Although some individual strains of fungi seemed to decrease the pathogen severity, plants were most protected against the pathogen when treated with a complex mixture of microbes prepared from homogenized leaves of these related plants.

This finding suggests that microbiome-based treatments could be a promising avenue of myrtle rust management for these endangered plants and emphasizes the beneficial effects microbiomes can have on their host plants. “We need to be thinking about the entire microbial community rather than any individual player,” noted lead author Chock.

Fungal transplants from close relatives help endangered plants fight off disease
Scanning electron microscope image of myrtle rust. Credit: Mason K. Chock

While beneficial microbes have been applied as biological control agents in agriculture, this new research suggests they could also be an important tool for plant conservation. Diseases pose one of the biggest challenges for endangered plants, especially since low genetic variation in their small populations limits efforts to breed them for disease resistance. Other solutions are temporary or potentially harmful in other ways, such as pesticide applications, which have to be continually applied to be effective and can have deleterious effects on soil health.

Thus, mining plant microbiomes for beneficial strains or communities that can confer disease resistance may be a promising strategy for combating disease-driven declines of endangered plants. And even if these microbial treatments are not strong enough to make their hosts completely disease resistant, every little bit of protection can help these endangered plants. While Chock does not think the study’s findings indicate that microbiome transplants are “a silver bullet to stopping myrtle rust’s worldwide spread,” he thinks they may provide an “extra push for those plant species that are holding on to dear life due to the introduction of deleterious pathogens.”


Explore furtherResearchers sequence myrtle rust genome


More information: M. K. Chock et al, Mycobiome Transplant Increases Resistance to Austropuccinia psidii in an Endangered Hawaiian Plant, Phytobiomes Journal (2021). DOI: 10.1094/PBIOMES-09-20-0065-RProvided by American Phytopathological Society

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Oliva released 10,000 predatory insects of the cotonet in 10 hectares of citrus fruits

The Department of Agriculture of Oliva has carried out a controlled release of the Cryptoleamus montrouzieri predatory insect in 10 hectares of citrus fields in the municipality of Oliva to deal with the cotonet pest that is affecting this municipality.

The Councilor for Agriculture, Miquel Doménech, received 10,000 specimens of Cryptoleamus -a voracious and highly effective predator of different pests- to continue with their biological control project, without using insecticides or toxins. The councilor thanked the different groups and agricultural associations that support the project and announced that there will be future releases.

Source: saforguia.com 

Publication date: Wed 29 Sep 2021

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