Predatory mites: Alternative to toxic insecticides


ABC Rural

 / By Jennifer Nichols

Posted 4h ago4 hours ago

A composite image with a red bug on the left and a man in a greenhouse on the right.
James Hill oversees the breeding of billions of Phytoseiulus persimilis bugs.(Supplied: Bugs for Bugs) link

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As concern over chemical use in food production grows and insect species become more resistant to poisons, farmers are turning to nature for solutions to pests that can cripple crop production.

Billions of tiny, blind, predatory mites are being bred, harvested, packed on ice, and posted to strawberry farms in the battle against destructive sap-sucking insects.

A man holds up a glass cup with red brown insects in the bottom of it.
James Hill with a cup of persimilis, from the arachnid family.(ABC Rural: Jennifer Nichols)

“We’re producing beneficial insects for farmers to use instead of insecticides,” Bugs for Bugs Donnybrook insectarium manager James Hill said.

“Ninety per cent of farmers in the strawberry industry are using our product.”

Ripe strawberries in a field.
Strawberries can now be grown with considerably fewer chemicals.(ABC Rural: Jennifer Nichols)

The battle

Australians love strawberries — 72 per cent of households bought them last financial year and on average we each ate around 2.27 kilograms of the fruit. 

One of the main insect enemies that farmers battle to produce tasty red strawberries is two-spotted mites, a sap-sucking species related to ticks, too tiny to spot with the naked eye.

A web like structure packed with tiny insects on a very sick looking bean leaf.
The two-spotted mite is bred to feed the Phytoseiulus persimilis bugs.(ABC Rural: Jennifer Nichols)

Left unchecked, you can see the damage two-spotted mites can do, sucking the life out of bean leaves in the polytunnels where they are raised as food for the predator mites that are sold to growers.

“If left unchecked the two-spotted mite would just devastate your crop, it would wipe you out,” Queensland Strawberry Growers president Adrian Schultz said.

A line of tiny insects hangs from a sick bean leaf.
A line of tiny insects hangs from a sick bean leaf.(ABC Rural: Jennifer Nichols)

The tiny warrior

An eight-legged member of the arachnid family, Phytoseiulus persimilis, is blind.

It hunts down two-spotted mites by touch and scent and can be dropped by drone to decimate populations of two-spotted mites and spider mites.

A magnified photo of a red coloured mite on a leaf.
Phytoseiulus persimilis thrives in humid conditions.(Supplied: Bugs for Bugs)

Just 0.5mm long, persimilis are voracious, specialised predators that breed twice as fast as their prey, can be carried on the wind, and are deployed to protect crops, greenhouses and commercial installations of indoor plants.

Once they have exterminated the pests they turn on their own eggs and larvae, posing no threat to other insects.

Mr Shultz said the insects have become real cost savers for big farms. Roy’s drone dropping beneficial bugs.

“In years gone by, we had to rotate different insecticides to control the two-spotted mite and you’d get a higher percentage of pests that were resistant,” he said.

“The advent of the predator mites enabled industry to use considerably less chemicals in controlling pests, now we also have the option of introducing lady beetles into our crops to control aphids.”

An older man dressed in blue farm work gear and brown boots kneels between rows of freshly planted strawberries. He smiles
Queensland Strawberry Growers Association president Adrian Schultz says the industry has embraced beneficial insects.(ABC Rural: Melanie Groves)

Integrated pest management

Integrated pest management (IPM) is increasingly popular with farmers and uses a range of preventive measures to control pests, including natural predators, parasites, nematodes, and pheromone traps.

“It’s not set and forget, you need to monitor the situation and you’ve got to be aware of the impacts of environmental conditions,” Mr Schultz said.

A man in a field of corn or maize.
Paul Jones helped pioneer beneficial insect breeding for horticulture in Australia.(Supplied: Bugs for Bugs)

Changing attitudes

The job satisfaction of helping farmers produce higher quality products with fewer chemicals is why Bugs for Bugs director Paul Jones has been working in integrated pest management for 30 years.

“When we first went out to farmers there was a lot of fear and scepticism about reducing the use of sprays and using beneficial insects to control pests,” the agricultural scientist said.

“The change has been quite radical, what was once considered a cottage industry for small organic and family farms has now become the backbone for pest management in conventional agriculture.” good bugs to fight bad bugs could be the key to pesticide-free farming

Bugs for Bugs is one of only a handful of commercial suppliers of beneficial insects in Australia.

From insectaries at Donnybrook, Toowoomba and Mundubbera, it sells 12 different species including predatory mites, ladybirds, lacewings, and parasitic wasps.

Home gardeners can also order the insects online.

Rows of polytunnels
Bugs for Bugs has expanded its insectaries.(ABC Rural: Jennifer Nichols)

Worldwide, predatory bioagents are being used to target gnats, thrips, caterpillars, scale, mealybugs, aphids, heliothis larvae, loopers, whitefly, and mites in crops including strawberries, raspberries, blackberries, cotton, macadamias, almonds, avocados, citrus, maize, cut flowers and hops.

Parasitic wasps kill fly maggots for the poultry, pig, dairy and feedlot industries, and black soldier fly larvae transform organic waste into compost.

A cup with tiny little insects in it.
Bugs for Bugs Phytoseiulus persimilis ready to be posted.(ABC Rural: Jennifer Nichols)

At the Donnybrook insectary, billions of persimilis are being harvested from polytunnels for the start of the Queensland winter strawberry season.

Each insect order is weighed and packed on ice to keep the persimilis mites in hibernation during transport.

A woman at a workbench.
Deb Hill packs predatory insects on ice and posts them to farmers.(ABC Rural: Jennifer Nichols)

A vermiculite mineral is included to make it easier for farmers to evenly spread the tiny predators on their fields.

“It’s evolved, refining the craft, we’ve got better and better,” Mr Jones said.

“Mainstream chemical companies now collaborate with us to ensure products are less harmful to beneficial insects.”

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Climate change is shifting the zones where plants grow


The Conversation

Published: March 22, 2024 8:34am EDT


  1. Matt KassonAssociate Professor of Mycology and Plant Pathology, West Virginia University

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Matt Kasson receives funding from the US Department of Agriculture.


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With the arrival of spring in North America, many people are gravitating to the gardening and landscaping section of home improvement stores, where displays are overstocked with eye-catching seed packs and benches are filled with potted annuals and perennials.

But some plants that once thrived in your yard may not flourish there now. To understand why, look to the U.S. Department of Agriculture’s recent update of its plant hardiness zone map, which has long helped gardeners and growers figure out which plants are most likely to thrive in a given location.

A U.S. map divided into colored geographic zones with a numbered key.
The 2023 USDA plant hardiness zone map shows the areas where plants can be expected to grow, based on extreme winter temperatures. Darker shades (purple to blue) denote colder zones, phasing southward into temperate (green) and warm zones (yellow and orange). USDA

Comparing the 2023 map to the previous version from 2012 clearly shows that as climate change warms the Earth, plant hardiness zones are shifting northward. On average, the coldest days of winter in our current climate, based on temperature records from 1991 through 2020, are 5 degrees Fahrenheit (2.8 Celsius) warmer than they were between 1976 and 2005.

In some areas, including the central Appalachians, northern New England and north central Idaho, winter temperatures have warmed by 1.5 hardiness zones – 15 degrees F (8.3 C) – over the same 30-year window. This warming changes the zones in which plants, whether annual or perennial, will ultimately succeed in a climate on the move.

U.S. map showing large areas colored tan, denoting a 5-degree increase in average winter minimum temperatures.
This map shows how plant hardiness zones have shifted northward from the 2012 to the 2023 USDA maps. A half-zone change corresponds to a tan area. Areas in white indicate zones that experienced minimal change. Prism Climate Group, Oregon State UniversityCC BY-ND

As a plant pathologist, I have devoted my career to understanding and addressing plant health issues. Many stresses not only shorten the lives of plants, but also affect their growth and productivity.

I am also a gardener who has seen firsthand how warming temperatures, pests and disease affect my annual harvest. By understanding climate change impacts on plant communities, you can help your garden reach its full potential in a warming world.

Hotter summers, warmer winters

There’s no question that the temperature trend is upward. From 2014 through 2023, the world experienced the 10 hottest summers ever recorded in 174 years of climate data. Just a few months of sweltering, unrelenting heat can significantly affect plant health, especially cool-season garden crops like broccoli, carrots, radishes and kale.

Radishes sprouting in a garden bed.
Radishes are cool-season garden crops that cannot withstand the hottest days of summer. Matt Kasson, CC BY-ND

Winters are also warming, and this matters for plants. The USDA defines plant hardiness zones based on the coldest average annual temperature in winter at a given location. Each zone represents a 10-degree F range, with zones numbered from 1 (coldest) to 13 (warmest). Zones are divided into 5-degree F half zones, which are lettered “a” (northern) or “b” (southern).

For example, the coldest hardiness zone in the lower 48 states on the new map, 3a, covers small pockets in the northernmost parts of Minnesota and has winter extreme temperatures of -40 F to -35 F. The warmest zone, 11b, is in Key West, Florida, where the coldest annual lows range from 45 F to 50 F.

On the 2012 map, northern Minnesota had a much more extensive and continuous zone 3a. North Dakota also had areas designated in this same zone, but those regions now have shifted completely into Canada. Zone 10b once covered the southern tip of mainland Florida, including Miami and Fort Lauderdale, but has now been pushed northward by a rapidly encroaching zone 11a.

Many people buy seeds or seedlings without thinking about hardiness zones, planting dates or disease risks. But when plants have to contend with temperature shifts, heat stress and disease, they will eventually struggle to survive in areas where they once thrived.

Successful gardening is still possible, though. Here are some things to consider before you plant:

Annuals versus perennials

Hardiness zones matter far less for annual plants, which germinate, flower and die in a single growing season, than for perennial plants that last for several years. Annuals typically avoid the lethal winter temperatures that define plant hardiness zones.

In fact, most annual seed packs don’t even list the plants’ hardiness zones. Instead, they provide sowing date guidelines by geographic region. It’s still important to follow those dates, which help ensure that frost-tender crops are not planted too early and that cool-season crops are not harvested too late in the year.

Orange flowers blooming with other plants and grasses.
California poppies are typically grown as annuals in cool areas, but can survive for several years in hardiness zones 8-10. The Marmot/FlickrCC BY

User-friendly perennials have broad hardiness zones

Many perennials can grow across wide temperature ranges. For example, hardy fig and hardy kiwifruit grow well in zones 4-8, an area that includes most of the Northeast, Midwest and Plains states. Raspberries are hardy in zones 3-9, and blackberries are hardy in zones 5-9. This eliminates a lot of guesswork for most gardeners, since a majority of U.S. states are dominated by two or more of these zones.

Nevertheless, it’s important to pay attention to plant tags to avoid selecting a variety or cultivar with a restricted hardiness zone over another with greater flexibility. Also, pay attention to instructions about proper sun exposure and planting dates after the last frost in your area.

Fruit trees are sensitive to temperature fluctuations

Fruit trees have two parts, the rootstock and the scion wood, that are grafted together to form a single tree. Rootstocks, which consist mainly of a root system, determine the tree’s size, timing of flowering and tolerance of soil-dwelling pests and pathogens. Scion wood, which supports the flowers and fruit, determines the fruit variety.

Most commercially available fruit trees can tolerate a wide range of hardiness zones. However, stone fruits like peaches, plums and cherries are more sensitive to temperature fluctuations within those zones – particularly abrupt swings in winter temperatures that create unpredictable freeze-thaw events.

Packages for hardy fig and kiwi seedlings.
Following planting instructions carefully can maximize plants’ chances of success. Matt Kasson, CC BY-ND

These seesaw weather episodes affect all types of fruit trees, but stone fruits appear to be more susceptible, possibly because they flower earlier in spring, have fewer hardy rootstock options, or have bark characteristics that make them more vulnerable to winter injury.

Perennial plants’ hardiness increases through the seasons in a process called hardening off, which conditions them for harsher temperatures, moisture loss in sun and wind, and full sun exposure. But a too-sudden autumn temperature drop can cause plants to die back in winter, an event known as winter kill. Similarly, a sudden spring temperature spike can lead to premature flowering and subsequent frost kill.

Pests are moving north too

Plants aren’t the only organisms constrained by temperature. With milder winters, southern insect pests and plant pathogens are expanding their ranges northward.

One example is Southern blight, a stem and root rot disease that affects 500 plant species and is caused by a fungus, Agroathelia rolfsii. It’s often thought of as affecting hot Southern gardens, but has become more commonplace recently in the Northeast U.S. on tomatoes, pumpkins and squash, and other crops, including apples in Pennsylvania.

A stem dotted with small round growths.
Southern blight (small round fungal structures) at the base of a tomato plant. Purdue UniversityCC BY-ND

Other plant pathogens may take advantage of milder winter temperatures, which leads to prolonged saturation of soils instead of freezing. Both plants and microbes are less active when soil is frozen, but in wet soil, microbes have an opportunity to colonize dormant perennial plant roots, leading to more disease.

It can be challenging to accept that climate change is stressing some of your garden favorites, but there are thousands of varieties of plants to suit both your interests and your hardiness zone. Growing plants is an opportunity to admire their flexibility and the features that enable many of them to thrive in a world of change.

Before you go…

Information is flying at us from all directions. And it can be overwhelming. Wouldn’t it be easier if you could get trusted science information in one place? That place is The Conversation. As an editor here, I am fortunate to work with scientists and researchers who explain their latest research. And each week, our team sends an email that brings together the best of our coverage of science, technology and environment.


Vivian Lam

Associate Health and Biomedicine Editor

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Copyright © 2010–2024, The Conversation US, Inc.


Grahame Jackson posted a new submission ‘A single laccase acts as a key component of environmental sensing in a broad host range fungal pathogen’


Grahame Jackson posted a new submission ‘A single laccase acts as a key component of environmental sensing in a broad host range fungal pathogen’

Saturday, 23 March 2024 08:16:28


Grahame Jackson posted a new submission ‘A single laccase acts as a key component of environmental sensing in a broad host range fungal pathogen’


A single laccase acts as a key component of environmental sensing in a broad host range fungal pathogen


Communications Biology volume 7, Article number: 348 (2024) 


Secreted laccases are important enzymes on a broad ecological scale for their role in mediating plant-microbe interactions, but within ascomycete fungi these enzymes have been primarily associated with melanin biosynthesis. In this study, a putatively secreted laccase, Sslac2, was characterized from the broad-host-range plant pathogen Sclerotinia sclerotiorum, which is largely unpigmented and is not dependent on melanogenesis for plant infection. Gene knockouts of Sslac2 demonstrate wide ranging developmental phenotypes and are functionally non-pathogenic. These mutants also displayed indiscriminate growth behaviors and enhanced biomass formation, seemingly as a result of their inability to respond to canonical environmental growth cues, a phenomenon further confirmed through chemical stress, physiological, and transcriptomic analyses. Transmission and scanning electron microscopy demonstrate apparent differences in extracellular matrix structure between WT and mutant strains that likely explain the inability of the mutants to respond to their environment. Targeting Sslac2 using host-induced gene silencing significantly improved resistance to S. sclerotiorum, suggesting that fungal laccases could be a valuable target of disease control. Collectively, we identified a laccase critical to the development and virulence of the broad-host-range pathogen S. sclerotiorum and propose a potentially novel role for fungal laccases in modulating environmental sensing.

Read on:

Saturday, 23 March 2024 08:16:28

Jackson posted a new submission ‘A single laccase acts as a key component of
environmental sensing in a broad host range fungal pathogen’


A single laccase acts as a key component of environmental sensing in a
broad host range fungal pathogen


 volume 7,
Article number: 348 (2024) 


Secreted laccases are important enzymes on a broad ecological scale for
their role in mediating plant-microbe interactions, but within ascomycete fungi
these enzymes have been primarily associated with melanin biosynthesis. In this
study, a putatively secreted laccase, Sslac2, was characterized
from the broad-host-range plant pathogen Sclerotinia sclerotiorum,
which is largely unpigmented and is not dependent on melanogenesis for plant
infection. Gene knockouts of Sslac2 demonstrate wide ranging
developmental phenotypes and are functionally non-pathogenic. These mutants
also displayed indiscriminate growth behaviors and enhanced biomass formation,
seemingly as a result of their inability to respond to canonical environmental
growth cues, a phenomenon further confirmed through chemical stress,
physiological, and transcriptomic analyses. Transmission and scanning electron
microscopy demonstrate apparent differences in extracellular matrix structure
between WT and mutant strains that likely explain the inability of the mutants
to respond to their environment. Targeting Sslac2 using
host-induced gene silencing significantly improved resistance to S.
, suggesting that fungal laccases could be a valuable target of
disease control. Collectively, we identified a laccase critical to the
development and virulence of the broad-host-range pathogen S.
 and propose a potentially novel role for fungal laccases
in modulating environmental sensing.

Read on:


UK: Plant breeders to benefit from online research tools


United Kingdom – Plant breeders to benefit from online research toolsSelect
April 3, 2024
 An exciting new project will look to put cutting-edge research tools in the hands of plant breeders, providing access to genomic resources to accelerate the development of more resilient and climate-resistant crops.The collaboration brings together the collective expertise of the Earlham Institute, IBM Research, the Science and Technology Facilities Council (STFC) Hartree Centre, and RAGT Seeds UK with the aim of simplifying and speeding up the transition of cutting-edge genome research tools, workflows, and software into industrial applications.The one-year Excelerate project is part of the Hartree National Centre for Digital Innovation (HNCDI) programme from STFC designed to close the gap between academic and industrial applications of digital technologies – such as artificial intelligence (AI) and quantum computing.The UK is home to some of the most exciting and innovative life science research. Institutions are pioneering the use of new technologies to overcome issues of scale and complexity in data-intensive bioscience, such as developing approaches that could be used to accelerate crop breeding in line with EU safety and ethical regulations.At the Earlham Institute, this includes crop pangenomes and the tools required to analyse them, developed through its Decoding Biodiversity strategic programme – funded by the Biotechnology and Biological Sciences Research Council (BBSRC), part of UKRI.But the transition of this knowledge into usable technology – and its uptake by industry – remains a significant challenge.“Modern plant breeding practices are based on understanding and then using genetic resources – made possible by digital innovations – that breeders can incorporate into their programmes,” Professor Anthony Hall, project lead and Head of Plant Genomics at the Earlham Institute explained.“Bioinformatics and machine learning techniques are playing an increasingly important role in deciphering genetic diversity. But they bring significant overheads in terms of the bioinformatics skills and computing power required to develop and implement new workflows.”The plant breeding industry has a crucial role to play in addressing the global challenges of food security, water conservation, and net zero. To realise the enormous potential of UK science and innovation, initiatives are needed to bridge the gap between research and industry.This new project brings together leaders from academia and industry to provide cloud-based tools that can be easily adopted by the plant breeding companies to support the development of next-generation crops with greater climate resilience and improved nutritional properties.The Earlham Institute is working with IBM Research and STFC to develop new cloud-based tools – including those optimised for exploring plant pangenomes – which RAGT Seeds UK will be road testing.“The Earlham Institute is home to some amazing research infrastructure, innovation, and expertise,” says Professor Hall. “This helps us to develop the technology needed to answer the big questions that will be critical in addressing urgent global challenges, such as how we find new sources of diversity for breeding more resilient crops.”
 The project team photographed with the London skyline behind them.
The project team from left to right: Robin Kennedy Reid, STFC, Rachel Rusholme-Pilcher, Earlham Institute, Laura Jayne-Gardiner, IBM Research, Will Davies, STFC, Anthony Hall, Earlham Institute, Chris Burt, Heidi Town, and John Baison, RAGT Seeds UK.
 Dr Rachel Rusholme-Pilcher is a Senior Postdoctoral Researcher at the Earlham Institute, and has played a central role in developing the workflows that will be used in this partnership.“The tools we’re developing and optimising will allow plant breeders to interact with their complex datasets in a way they simply couldn’t before,” explained Dr Rusholme-Pilcher. “It should provide new information they can rapidly incorporate into their existing breeding programmes.“We’ll also be using this project to look at how we can embed the adoption of FAIR approaches – the movement to make all research data Findable, Accessible, Interoperable, and Reusable. Making this kind of research FAIR can be a challenge but these collaborations will hopefully change that – transforming the impact of emerging technologies.”Excelerate is one strand of a number of projects from HNCDI embedding AI solutions across UK industry. To both accelerate and simplify the adoption of compute intensive bioinformatics workflows in the plant breeding industry, this project will use an on-demand, scalable, Hybrid Cloud delivery model.Dr Laura-Jayne Gardiner, Senior Research Scientist at IBM Research, said: “Our HNCDI Excelerate projects are enabling businesses to adopt new technologies – including artificial intelligence and hybrid cloud – to overcome industrial challenges, such as allowing complex biological data analytics at increased scale and speed.”Robin Kennedy-Reid, Senior Research Software Engineer at the STFC Hartree Centre, said: “At the Hartree Centre, we use applied research and innovation to turn good ideas into industry-ready solutions for long-term societal and economic impact. This is made possible by working with a network of partners, both industry and academic leaders, as well as drawing on the work of open source communities like nf-core.“In this project, this will deliver new bioinformatics and machine learning capability to the plant breeding industry; with a view to assisting the search for more sustainable wheat varieties.”Dr John Baison, Cereals Research and Genomics Manager at RAGT Seeds UK, said: “Genome-based breeding holds promise for expediting wheat breeding, aiming to ensure sustainable wheat production by creating high-yielding, climate-resilient cultivars with superior nutritional quality.“The plant-breeding sector is positioning to confront these targets by leveraging the dynamic UK research community. However, bridging the gap between research and industry is crucial for optimising the potential of UK science and innovation.“As RAGT delves deeper into genomics activities, it has become increasingly evident that we must harness advanced computing tools to navigate the vast amounts of data generated from genetics and genomics projects. RAGT is excited to be at the forefront of this collaborative effort, which could revolutionise the application of genomics to plant breeding.” 

More news from:
    . Earlham Institute
    . RAGT Seeds Limited
Website April 3, 2024


new way to identify pesticide resistance


new way to identify pesticide resistance

Tina Deines

Sun, April 7, 2024 at 12:00 PM CDT·2 min read

Researchers are exploring an exciting new approach that uses genomics to help monitor and identify pesticide resistance in the insects that munch on our crops.

Pest management is important for farmers, but insects often become immune to pesticides, making them less effective. In the new research, published in the Proceedings of the National Academy of Science, a team of scientists from the University of Maryland (UMD) presents a new strategy that analyzes genomic changes in pests to monitor and identify emerging resistance to specific toxins early on.

They zoned in on one pest in particular: the corn earworm, a crop-destroying caterpillar that has developed widespread resistance to a number of natural toxins bred into corn. They were able to identify resistance to toxins among these caterpillars after just a single generation of exposure. They also identified how common strategies for avoiding resistance could actually be doing the opposite.

“As it currently stands, the evolution of resistance across many pests of agricultural and public health importance is outpacing the rate at which we can discover new technologies to manage them,” said senior author Megan Fritz, an associate professor of entomology at UMD, per “I’m really excited about this study, because we’re developing the framework for use of genomic approaches to monitor and manage resistance in any system.”

The new research is one of many that is helping farmers to produce more successful harvests.

For instance, a team of American and Chinese researchers found a way to genetically engineer plants that can survive heat waves. University of Minnesota scientists are on their way to developing a “Super Grape” that could stave off powdery mildew and reduce the need for fungicide.

Watch now: What’s the true environmental impact of renewable energy?

These developments in agriculture come at a critically important time — as our planet continues to warm, there are frequent heat waves and droughts, which threaten our food security. Plus, climate change scientists predict that a warming world will drive a surge in certain insect pests that attack our crops, further threatening food security and causing economic losses for those in the agricultural sector.

Join our free newsletter for weekly updates on the coolest innovations improving our lives and saving our planet.


Kansas, USA: Robots developed to take on a labor-intensive process — cutting weeds down


Harvest Public Media | By Celia Hack

Published April 8, 2024 at 4:00 AM CDT

LISTEN • 3:20

GreenField robots at sunset.

Greenfield Robotics, a Kansas-based company, is hoping to move agriculture away from herbicides. They’ve developed robots to take on a labor-intensive process — cutting weeds down.

Three yellow, bug-like creatures crawl in perfectly straight lines across the dead grass of a flat, brown February field in Cheney, Kansas.

These are the namesake of GreenField Robotics. Two lights peer out from each side of the boxy machines, almost appearing like eyes. Blades whir at their base, about a half an inch from the ground – the perfect height to chop weeds, though there’s nothing to cut down on a frigid winter day.

They stick out in an otherwise rural landscape – and GreenField CEO Clint Brauer said he frequently hears from curious passersby.

“All the time,” Brauer said. “I’m always surprised, though, how little people notice.”

Brauer founded the company in 2018. The start-up has now grown large enough to attract investment from Chipotle’s $100 million venture capital fund and to secure partnerships with dog food and baking mix brands.

Brauer grew up on a family farm in Haven, Kansas, but moved to California after high school to work in the tech industry. In 2010, he returned home after his dad was diagnosed with Parkinson’s disease. He attributes the use of herbicides to his dad’s diagnosis.

“The more I learned about farm chemicals and stuff … the more I thought there’s a decent chance that this came from that,” Brauer said.

GreenField Robotics CEO and Founder Clint Brauer with two robots in Cheney, Kansas.
GreenField Robotics CEO and Founder Clint Brauer with two robots in Cheney, Kansas.

The move sucked Brauer back into the world of agriculture, where he started seeking ways to eliminate herbicides. He tried farming organically, but it was too expensive to be accessible to many buyers.

Another option was no till farming, where farmers avoid turning over the dirt to reduce erosion and improve soil health. But it’s a method that leans on herbicides.

And in 2015, Brauer was starting to notice the weeds in his fields were becoming resistant to chemicals anyway.

“There was no good way to get rid of those weeds, even though we had sprayed many times,” Brauer said.

“So, what do we do? And so that was the beginning of this idea of – what if we just cut those weeds?”

Cutting weeds by hand wasn’t exactly a 21st-century answer. So Brauer thought: What about robots? He reached out to software and machine-vision experts and started prototyping robots.

By 2021, the company had manufactured a two-and-a-half foot-tall working robot. And it pulled together different technologies, like drones, to create extremely precise maps of crop fields. The robots follow the maps, so that they’re unlikely to accidentally chop down a crop instead of a weed.

“They plant the crop, we count about 10 days, normally, the crops emerge, and we fly over it with a drone,” Brauer said. “ … That’s where AI – we have machine vision that automatically recognizes everything that’s going on in that field.”

Thirty to 40 days later, Brauer sends out the robots.

GreenFields' robots working a field.
GreenFields’ robots working a field.

In 2022, the company partnered with MKC, a major agricultural cooperative, to reach farmers who might use the product. In 2023, GreenField Robotics worked with 25 to 30 Kansas farmers, Brauer said. The company currently has a fleet of 20 robots and 15 employees

This summer, Brauer said the company is planning to work the weed-cutting robots on over 20,000 acres.

John Niemann is a farmer in Reno County. He tested GreenField Robotics for the first time last spring on 80 acres of a sorghum field, leaving 10 acres untouched to compare results. He had treated the entire crop with herbicides earlier in the season.

“We saw higher yields where we used the robots, versus the 10 acres that we did not,” Niemann said.

That’s because the weeds that didn’t get chopped down in the 10 acres competed with the crop for moisture, hampering the yield.

“The robots are part of a toolbox, is how I would look at them,” Niemann said. “There is no magic bullet in farming practices. You need to have a lot of tools in your toolbox.”

Niemann says the robots are a useful tool to reduce reliance on chemicals. Plus, he said the cost was comparable to herbicides.

Brauer said the economics is always his first pitch to farmers, and the robots are compelling because they damage less of the crop than chemicals do.

The company is also adapting the robots for other uses, like planting cover crops and soil testing.

“We are on a mission,” Brauer said. “This is not about enrichment. This is – we’re building something that can’t be undone. And so we’re going to eliminate these chemicals.”

This story was first aired and produced by KMUW. It’s being distributed by Harvest Public Media, a collaboration of public media newsrooms in the Midwest. It reports on food systems, agriculture and rural issues.


News farmingregenerative farmingrobotsagriculture


Jamaica: Lethal yellowing of coconut palm


Saturday, 09 March 2024 10:37:00

Grahame Jackson posted a new submission ‘LETHAL YELLOWING, COCONUT PALM – JAMAICA’




Source: Jamaica Observer [summ. Mod.DHA, edited]

Through the work of the Coconut Industry Board (CIB), Jamaica has been able to reduce the spread of the lethal yellowing disease in the coconut industry by 70%. CIB have contributed significantly through research which has allowed the development of varieties and hybrids with optimum resistance/tolerance to lethal yellowing. In addition, increased yields are obtained from these locally developed varieties that are adapting better to the climatic conditions.

Within the region, the disease was first discovered in the Cayman Islands in 1834 and was found in Jamaica in 1884. It became a real threat to Jamaica after 1961 and became even more significant in the 1970s when some 10 million trees of the ‘Jamaican Tall’ variety were destroyed. Lethal yellowing has caused severe economic losses in Jamaica.

Communicated by:

[Lethal yellowing (LY) diseases of coconut and other palms are caused by phytoplasmas of the palm lethal yellowing (16SrIV; _Candidatus_ Phytoplasma palmae strains) group. A number of LY strains have been described from the Caribbean, Latin America, Africa and southern Asia. LY has seriously jeopardised coconut industries in the respective areas. LY-type diseases like Cape St Paul wilt (CSPW) in Ghana, the “maladie de Kaincope” in Togo and Awka disease (lethal decline, LD) in Nigeria, previously included in the 16SrIV group, have been reclassified as the new group 16SrXXII (Nigerian coconut lethal decline group, _Ca._ P. palmicola strains; see link below).

Symptoms include premature nut drop, blackening of inflorescences, yellowing of fronds; death of the palm usually occurs within 4 to 6 months. The planthopper _Myndus crudus_ is suspected to be the vector in the Americas, but different vectors may be involved in the spread of LY strains elsewhere. Seed transmission of the pathogens cannot be excluded; some weed species may serve as pathogen reservoirs. Jumps of LY across apparently unaffected coconut populations have been observed, possibly due to aerial spread of infectious vector insects or human activities. Even with strict controls, including certification of nuts and their parent trees, excluding infectious vector insects requires large quarantine efforts.

While LY affects many palm species, at least for coconut palm susceptibility may vary between cultivars or even within cultivars, depending on the region where they grow. Symptoms can be suppressed by tetracycline treatments, usually applied as trunk injections. The antibiotic inhibits multiplication of the pathogens but does not eliminate them. Therefore, treatments need to be repeated regularly. Commercial control of the diseases mostly relies on phytosanitation followed by replanting with resistant varieties.

An unexplained resistance breakdown of some widely used hybrids occurred earlier in Jamaica (ProMED post 20070522.1643) and caused great concern.

LY symptoms on coconut and other palms:,×512/1504008.jpg, (leaf) and (fruit)
_Myndus crudus_:×512/0725079.jpg

Story also at: and
Lethal yellowing information:,,,, and
16SrIV LY phytoplasma group taxonomy and species list:
16SrXXII classification of some LY-type diseases:
16SrXXII LDN phytoplasma group taxonomy:
Phytoplasma resource centre:
Information on LY vectors via:
– Mod.DHA


EU: Food security top priority for 2024-2029


By Sofia Sanchez Manzanaro | Euractiv

 Est. 3min

 Apr 9, 2024 (updated:  Apr 10, 2024)

Content-Type: News

The Strategic Agenda, which defines the EU’s priorities for the 2024-2029 mandate and provides guidance for the Brussels-based institutions, will be adopted by the 27 heads of state and government during the European Council meeting of 27-28 June. [EPA/OLIVIER HOSLET]

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EU leaders are expected to put food security at the heart of the bloc’s agricultural policy for the next five years, according to a leaked draft of the EU’s Strategic Agenda seen by Euractiv.

The programme defines Europe’s priorities for the 2024-2029 mandate, providing guidance to the EU institutions, and will be adopted by the 27 heads of state and government during the European Council meeting on 27-28 June.

The internal document, created on 27 March, predates the most recent exchanges between the EU leaders, and points to food security as a key priority for a “prosperous and competitive Europe,” despite the issue hardly being discussed at EU summits in recent years.

“Ensure our food security through a vibrant agriculture sector,” reads one of the bullet points of the draft outline.

The two-page text does not explicitly reference the sustainability of the agricultural sector or the protection of the environment, even though it prioritises “preparing for the new realities stemming from climate change.”

From sustainability to security

This initial draft marks a departure from the 2019 priorities, which included “promoting sustainable agriculture” and “calling on all EU countries to move forward and step up their climate action”.

In response to widespread farmer protests across the EU, the European Commission has already shelved or backtracked some of its plans to improve the sustainability of the farming sector in recent months.

Faustine Bas-Defossez, director for health, nature, and environment at the European Environmental Bureau (EEB), described the absence of sustainable agriculture in the leaked 2024 agenda as “deeply troubling”.

“By prioritising’ food security’ over sustainability in agriculture, EU leaders are ignoring the reality that climate change and natural disasters pose the greatest threats to our food security,” she warned.

A study commissioned by the European Parliament’s Agricultural Committee found that while food availability in the EU “is not generally considered to be at risk,” the bloc relies too heavily on imports from a reduced group of suppliers for animal feed and fertilisers.

According to the report, those dependencies, exacerbated by an uncertain geopolitical situation and climate change, could threaten the long-term resilience of the EU food system.

The study however also found that sustainable farming practices, such as organic agriculture and the promotion of lower consumption of animal products, could decrease the bloc’s need for imports.

EU is too dependent on animal feed and fertiliser imports, warns Parliament study

The EU remains heavily reliant on animal feed and fertilisers imports from outside the bloc, as highlighted in a recent study commissioned by the European Parliament’s Agriculture Committee (AGRI).

[Edited by Angelo Di Mambro and Rajnish Singh]


The genetic composition of fungi and its role in plant health


by University of Ottawa

Population analyses of R. irregularis. Credit: Nature Microbiology (2023). DOI: 10.1038/s41564-023-01495-8

The complex and very diverse world of fungi is often referred to as the fifth kingdom of organisms. It includes various yeasts, molds, and mushrooms. A team of scientists from the University of Ottawa (uOttawa) has uncovered the genetic secrets of a mysterious fungus, revealing the presence of two distinct nuclear populations within them, each playing distinct roles in how they interact with plants.

Arbuscular mycorrhizal fungi (AMF) are tiny fungi that live in harmony with plants, sharing their genetic diversity and creating a vibrant atmosphere in plant roots and with below-ground microbes. Scientists have been studying AMF for years but are still puzzled by it. Its bodies are like bags packed with thousands of nuclei cells, and how these fungi cooperate with plants has long been unclear.

“There were numerous unresolved questions regarding AMF, mainly because these fungi are always multinucleated and do not exhibit observable sexual characteristics,” says Professor Nicolas Corradi, who holds the Chair in Microbial Genomics at the Department of Biology, University of Ottawa. “It has been proposed that AMF possess unique genetics and have undergone an unconventional evolution.”

Professor Corradi and colleagues investigated the asexual reproduction of AMF, specifically Rhizophagus irregularis. In 2016, they discovered strains that showed signs of sexual reproduction, with two populations of nuclei co-existing in large cells. “We found that strains having two populations (AMF heterokaryons) are more resilient and could access plant roots more easily, an indication they could be better bio-stimulants.”

However, without their complete genome, the researchers could not know why these strains are more successful plant symbionts.

Exploring the genetic composition of fungi and its role in plant health
Phylogenetic tree constructed with 65 R. irregularis strains. Haplotypes from AMF heterokaryons are shown in yellow squares. Based on relative branch lengths, the phylogeny resolves at least nine clades, which are highlighted in color. The tree was made using IQTREE algorithm, in GTR-FO mode with 1,000 bootstrap replicates. Scale bar represents 0.05 substitutions per site. When available, the MAT type of the strain is shown in parentheses. Note: the G1 strain located in clade VI noted with an asterisk is homokaryotic and does not represent the heterokaryotic isolate G1 (DAOM-970895) from clade IV. Credit: Nature Microbiology (2023). DOI: 10.1038/s41564-023-01495-8

To address this, Professor Corradi and his team employed advanced sequencing techniques, including RNA sequencing and third-generation DNA sequencing, to analyze differences in structure, content, and expression between the co-existing genomes.

“AMF heterokaryons have two haplotypes that physically separate among a large number, possibly millions, of co-existing nuclei. This phenomenon is unprecedented in any other organism,” explains Professor Corradi.

Their analyses also demonstrated that the two populations act very differently depending on their surrounding environment and their plant host. “Not only did we find that the two populations differ dramatically in the genes they harbor, but also that these are differently expressed and change in abundance depending on which plant they interact with,” adds Professor Corradi.

The symbiotic interactions between AMF and host plants are crucial for nutrient exchange, pathogen protection, and ecosystem sustainability. Studying these interactions will help improve agricultural practices by producing tailored biostimulants, enhancing plant growth, and promoting ecosystem health.

The study, titled “Arbuscular mycorrhizal fungi heterokaryons have two nuclear populations with distinct roles in host–plant interactions,” was published in Nature Microbiology.

More information: Jana Sperschneider et al, Arbuscular mycorrhizal fungi heterokaryons have two nuclear populations with distinct roles in host–plant interactions, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01495-8

Journal information: Nature Microbiology 

Provided by University of Ottawa 

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In symbiosis: Plants control the genetics of microbes


Horizontal gene transfer: How fungi improve their ability to infect insects


by Eva Sittig, Kiel University

The research team investigated genetic changes of Metarhizium fungi during infection of the invasive Argentine ant, shown here are its workers, on the right with brood. Credit: Sina Metzler & Roland Ferrigato, ISTA

Researchers at the Kiel Evolution Center have investigated for the first time in detail how a fungus important for biological plant protection can pass on an advantageous chromosome horizontally, using a previously little-studied way of exchanging genetic information.

Sustainable plant protection measures that are not based on chemical pesticides rely on various organisms and biological agents to protect crops from pests. Such organisms used for biological plant protection are, for example, microscopic fungi of the genus Metarhizium, which can attack and kill a variety of plant-pathogenic insects and are used, for example, in South American sugar cane cultivation.

The molecular mechanisms of fungal infection and the immune response of insects are in an ongoing process of mutual evolutionary adaptation. In a joint project with colleagues from the Institute of Science and Technology Austria (ISTA), a research team from Kiel University investigated the genetic changes in the fungus during infection of the invasive Argentine ant (Linepithema humile).

The researchers examined the genomes of different strains of the fungi Metarhizium robertsii and Metarhizium brunneum from an earlier co-infection experiment in which ants had been infected with the fungus mix.

In the study, the outgrowing spores were used to infect new ants over 10 consecutive infection cycles. When analyzing the fungal genomes from these infection series, the fungal geneticist and first author of the study, Dr. Michael Habig from Kiel University, made an exciting observation: his analyses showed that a single chromosome was very frequently exchanged horizontally between two different strains.

This chromosome contains certain genes that the scientists suspect may give the fungus an advantage in infecting its hosts. The horizontal transfer of entire chromosomes has rarely been described scientifically and has now been studied in detail for the first time. The researchers from the Kiel Evolution Center (KEC) and ISTA published their results in the journal Proceedings of the National Academy of Sciences.

Horizontal chromosome transfer detected in insect-damaging fungus

Scientists use the term horizontal gene transfer to describe how living organisms can transfer genetic material between different individuals, including those of other species. In this way, bacteria exchange extensive genetic information, often in the form of plasmids, in order to quickly adapt to changing environmental conditions or to adapt to the host. The rapid evolution of various pathogens is based on such mechanisms, among other things.

“In fungi and many other so-called eukaryotic organisms, however, horizontal gene transfer in the form of entire chromosomes is very rare and has hardly been researched to date,” says Dr. Michael Habig, research associate at Kiel University.

“The analysis of the genetic information of the fungal strains shows that M. robertsii independently transferred a single chromosome a total of five times during the co-infection experiments, but no other genetic information from one strain to another via horizontal transfer,” continued Habig.

Further analyses also indicated that the same chromosome can also be found in the distantly related, also insect-damaging fungus species Metarhizium guizhouense, whose common evolutionary origin with M. robertsii dates back around 15 million years.

“The chromosome in M. guizhouense is significantly less altered than would be assumed for the long period of separate evolution of the two fungal species. The chromosome therefore also appears to have been passed on naturally between these different fungal species—and probably horizontally,” says Habig.

Analysis of the chromosome indicates possible survival advantages for the fungus

The chromosome examined is a so-called accessory chromosome. This means that it does not occur in all individuals of a species and contains non-essential genetic information.

“The experiments showed that, under certain conditions, the fungus that had received the accessory chromosome had competitive advantages over fungi of the same strain that had not received the chromosome and were able to prevail against them. We want to investigate the details of these advantages in more detail in the future,” says Habig.

The Kiel research team has already been able to derive initial indications from the analysis of the genes on the chromosome. “The chromosome contains hundreds of genes whose potential functions we will only be able to decipher in the future. However, we have already been able to identify 13 candidate genes that could presumably be responsible for so-called effector proteins, which can interact with the insects’ immune system, for example,” Habig continues.

The transfer of the chromosome may therefore have advantages for the fungus, the functional basis of which is still unclear. However, one plausible possibility is the transfer of certain genes that produce chitin-cleaving enzymes and can thus improve the ability to infect the insects.

“It is remarkable that we have found the genes of three such enzymes, among others, which presumably play a role in the degradation of the chitin-containing cuticle of the host insect. This could influence a crucial step in the infection process, as the fungal spores are dependent on penetrating the protective exoskeleton of the host in order to infect it,” says Professor Sylvia Cremer, last author of the study, from the Institute of Science and Technology Austria (ISTA).

Overall, the research work offers interesting new aspects on a way of exchanging genetic information that has been little studied in fungi to date.

“Our new work shows that horizontal chromosome transfer occurs regularly in fungi and that this mechanism can confer advantages to the recipient strain, at least in experiments under certain conditions,” says Habig.

The Kiel research team and its collaboration partners from ISTA thus describe in detail for the first time a new aspect in the genome evolution of fungi, which may be able to use bacteria-like mechanisms of rapid evolutionary adaptation, for example to increase their virulence or harmfulness to their host organism and to transfer genetic information across species boundaries.

In the future, the researchers want to use the example of M. robertsii to investigate the relationships between horizontal chromosome transfer, possible fitness advantages and the mutual adaptation of fungi and insects in detail and thus gain further insights into this organism, which is important for plant protection.

More information: Michael Habig et al, Frequent horizontal chromosome transfer between asexual fungal insect pathogens, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2316284121

Journal information: Proceedings of the National Academy of Sciences 

Provided by Kiel University 

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Examining the promotion of Arabidopsis immune responses by a rhizosphere fungus