Produced by the International Association for the Plant Protection Sciences (IAPPS). To join IAPPS and receive the Crop Protection journal online go to: www.plantprotection.org
James Hill oversees the breeding of billions of Phytoseiulus persimilis bugs.(Supplied: Bugs for Bugs)
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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.
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.”
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.
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.(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.
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.
“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.”
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.
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.”
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.
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.
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.
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.”
FP Next – Deep Dive: The coordinator of Nebraska’s On-Farm Research Network shares insights into studies on crop biologicals and their impact on your bottom line.
CHECK IT OUT: One of the best ways to decide which crop biologicals or nontraditional crop products work in your geographic area and cropping management system is to test them out in your own fields. CURT ARENS
At a Glance
There are hundreds of biologicals, biostimulants and other nontraditional crop products on the market.
A starting point in testing these products might be planting simple “with” and “without” test strips across a field.
Planting test strips across a range of nitrogen rates, along with check strips, offer the most useful results.
It’s like the Wild West out there in the world of crop biologicals. There are hundreds of products, but many farmers don’t know where to start to decide which ones, if any, will boost their bottom line, improve crop health or reduce nutrient inputs.
There are many questions. How do I decide which biologicals will work on my farm? How do I know if they are worth the money? Where do I start to test in the field what works on our own farm?
The new Farm Progress podcast — FP Next — powered by John Deere, sets out to answer those questions by visiting with Laura Thompson, Nebraska’s On-Farm Research Network coordinator, in a Deep Dive episode (listen below). Listen to all episodes of FP Next.
Burning questions
Gleaned from the podcast, here are some of the questions Thompson answered, shedding light not only on biologicals and other nontraditional crop products, but also talking about how farmers can test the effectiveness of these products on their own farms.
What exactly are crop biologicals and biostimulants and why are they important? There are a lot of different products that we categorize as biologicals or biostimulants. In our on-farm research, a lot of times we look at these products as what we call more nontraditional products. These could be things like biologicals, biostimulants, as well as other things. But we’re looking at products here that have been derived from natural materials. These include beneficial microorganisms. These could be things like bacteria or fungi, but also products like seaweed extracts, amino acids, humic acids and organic compounds.
Regardless, the idea is to try to stimulate or interact with the plant and the soil to help promote growth, or it could be increasing nutrient uptake. There are a variety of reasons producers might be interested in utilizing these products. They have gained a lot of attention recently, and the reasons for that are there is interest in reducing chemical inputs, and an emphasis on soil health and how we can promote more sustainable farming practices.
These products are available for a wide variety of crops like corn, soybeans and dry edible beans, but also high-value crops and horticultural crops.
Tell us about some of your most recent studies relating to biologicals in the field. We’ve had product testing dating back many years. One of the benefits of doing that research through the On-Farm Research Network is that we have a nice repository of those studies available now. We have what is called our results finder database, where you can search and filter by different products and product names in different categories and look at how those products are performing for different people in different parts of the state, and in different production systems.
Studies that people are looking at include some commercial products like Pivot Bio and other products. A large variety of products have been tested over the years. And then some producers look at their own products as well, like homemade compost tea extracts, for instance.
Something that’s fun about our On-Farm Research Network is that it is really farmer-driven. We have such a huge variety of studies in our network because we have all the innovative and curious farmers across the area coming up with the different topics they are interested in, and we’re working with them on those studies.
These producers testing some of their own extract products are really interested in seeing how these impact (their operations) over the long term. That’s beneficial because we think about these products as being biologicals. We know that it takes time in a system to make a difference, for the system to adapt and change and to start to measure what the change might be in terms of synthetic fertilizer applications, herbicide applications and soil health.
Where do you start and how do you decide whether these products are paying off in the long run? Knowing we have such different conditions, soils, landscapes and management practices is why on-farm research is most beneficial for producers. It doesn’t have to be that complicated to test a product. But as you’re thinking about adopting a new product into your operation, it’s important that producers are getting data on how that product is performing. We all come with our bias.
If we purchased that product, we want to see how it works. If we’re just anecdotally looking to apply to the whole field and kind of going with a gut feeling, it’s natural to have a bias since we paid for a product. We want to see something, whether it is there or not.
Maybe do a test on a couple of fields first. Maybe this is the year you put in some check strips and collect the data for yourself. Maybe you will see that your gut feeling is correct, or maybe it is not what you thought.
How can producers evaluate these products on nutrient uptake for instance in their own fields? A lot of these products are looking at things like providing nitrogen for the crop. Producers often set up trials that do some simple “with” and “without” product tests. That’s a great starting point.
With precision ag technology, we’re seeing producers looking at these products at a variable nitrogen rate, maybe applying a range of nitrogen rates, maybe ranging from 75 pounds to 200 pounds of N. Applying biological products across those rates and leaving a check across those rates as well helps us look at the impact.
One of the challenges producers faced in the first couple of years of testing these products was that they would do a test over a reduced nitrogen rate and maybe see no impact for that product. This can be discouraging. But we don’t know if that N rate they were testing was already in excess of the optimal rate. That’s why we’re trying to work with producers to test across a wider range of N rates to see what product impacts might be at the optimal N rate with and without the product. This gives us a chance to see where that product might fit.
Another benefit of doing this kind of variable-rate approach and putting it into a prescription like this is that we can test it with different geographies within the field. Maybe we have some silty clay loam, and maybe we have a sandy pocket in the field. We can see if we have any difference.
In some cases, we’re not seeing an impact with these products. But that’s the depth of the testing we need to do to verify if that is the case for each producer in each region of the field. If we are not seeing a positive response, then it is still important information to have going forward in making management decisions.
Curt Arens began writing about Nebraska’s farm families when he was in high school. Before joining Farm Progress as a field editor in April 2010, he had worked as a freelance farm writer for 27 years, first for newspapers and then for farm magazines, including Nebraska Farmer.
His real full-time career, however, during that same period was farming his family’s fourth generation land in northeast Nebraska. He also operated his Christmas tree farm and grew black oil sunflowers for wild birdseed. Curt continues to raise corn, soybeans and alfalfa and runs a cow-calf herd.
Curt and his wife Donna have four children, Lauren, Taylor, Zachary and Benjamin. They are active in their church and St. Rose School in Crofton, where Donna teaches and their children attend classes.
Previously, the 1986 University of Nebraska animal science graduate wrote a weekly rural life column, developed a farm radio program and wrote books about farm direct marketing and farmers markets. He received media honors from the Nebraska Forest Service, Center for Rural Affairs and Northeast Nebraska Experimental Farm Association.
He wrote about the spiritual side of farming in his 2008 book, “Down to Earth: Celebrating a Blessed Life on the Land,” garnering a Catholic Press Association award.
Sarah McNaughton of Bismarck, N.D., has been editor of Dakota Farmer since 2021. Before working at Farm Progress, she was an NDSU 4-H Extension agent in Cass County, N.D. Prior to that, she was a farm and ranch reporter at KFGO Radio in Fargo.
McNaughton is a graduate of North Dakota State University, with a bachelor’s degree in ag communications and a master’s in Extension education and youth development.
She is involved in agriculture in both her professional and personal life, as a member of North Dakota Agri-Women, Agriculture Communicators Network Sigma Alpha Professional Agriculture Sorority Alumni and Professional Women in Agri-business. As a life-long 4-H’er, she is a regular volunteer for North Dakota 4-H programs and events.
In her free time, she is an avid backpacker and hiker, and can be found most summer weekends at rodeos around the Midwest.
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‘Dinosaur’ pesticide law clings to life as SA dithers on poisons reform
Some critics suggest that South Africa remains locked in a chemical culture time warp, where pesticides continue to be cast in a ‘heroic’ role, discouraging less toxic products and non- chemical weed and insect control alternatives. (Photo: schmidtlaw.com / Wikipedia)
There are more than 3,000 registered pesticides sprayed across South Africa, several of which are banned or severely restricted in Europe and other countries because of human and environmental safety risks. Despite the government’s promises to reform outdated pesticide policies, public health experts say there has been little movement.
It has been 77 years since the first law to regulate chemical pesticide safety was passed in this country. This was back in the days of King George VI, Jan Smuts and the Union of South Africa.
Since then, South Africa has become the largest consumer of pesticides in Africa, accounting for roughly a third of all farm chemicals used on the continent.
The primary law regulating pesticides dates back to 1947, but there are more than a dozen other laws, with overall administration fragmented between seven different government departments. (Government Gazette and Wikimedia Commons / Library of Congress Prints and Photographs Division)
Here is one example: The current Act still specifies a fine of “£500” for government officials who unlawfully disclose any confidential business affairs of the agricultural industry.
Juxtaposed against this £500 fine (roughly R12,000 at today’s exchange rate), the current version of the Act only permits a maximum penalty of R1,000 for violations of the country’s main pesticide control law.
The Adjustment of Fines Act of 1991 does provide for a retrospective stiffening of fines using a ratio determined by periodic government notices, so the R1,000 fine may now be closer to R80,000.
Nevertheless, the £500 fine crafted to protect industry secrecy and the derisory scale of maximum fines for pesticide law violations, remain on South Africa’s statute book – stark evidence of an outdated legal legacy and powerful influence of vested industry interests in an era where modern agricultural systems seemingly remain addicted to chemical poisons to sustain the growth of food or cash crops.
As evidence continues to pile up about the serious harm to humanity and the environment from the increasing volumes of pesticides sprayed across the world, the government has failed to implement a series of reforms recommended by its own policy document – the “new” Pesticide Management Policy published 14 years ago.
Several pesticides have been shown to increase the risk of cancer and obesity, along with neurological damage to children, kidney and lung disease and other serious health impacts. (Image: Brewer International / Wikipedia)
There has also been a two-decade delay in passing domestic laws to enforce the Rotterdam Convention, an international treaty ratified by South Africa in 2002 to limit the global movement of banned or severely restricted pesticides.
It was only in May 2021 that Forestry, Fisheries and the Environment Minister Barbara Creecy gazetted new Rotterdam domestic regulations, which introduced new penalties of up to R5-million for pesticide manufacturers and distributors who either import or export hazardous chemical and pesticide formulations in contravention of the international treaty obligations.
But in November 2021, Creecy changed her mind and suspended the implementation of the new regulations for 12 months. Following a further series of delays, she has since repealed the original regulations and published a new version that is only due to take effect in mid-June 2024 (barring further delays).
Creecy’s department has rejected claims of any improper influence from the agrochemicals industry in delaying the new Rotterdam domestic regulations and attributed some of the delays to “substantive” objections that included the apparent omission of CAS chemical registry numbers from the published regulations.
Croplife SA, an industry body whose members include agrochemical companies such as BASF, Bayer, Corteva, UPL and Syngenta, says it is also “not of the opinion that Minister Creecy is intentionally delaying the implementation, but rather ensuring that the regulations are free of errors, which is of paramount importance”.
Nevertheless, documents on its website suggest that it is pushing back against international pressure to phase out at least 29 chemical substances linked to greater risks of cancer, genetic damage and other harms to people, animals and the environment.
Members of the Women on Farms Project marched in Worcester on 5 May 2022 demanding an urgent ban on 67 pesticides. (Photo: Ashraf Hendricks)
At a series of workshops last May for farmers, government officials and journalists, senior Croplife leaders said there was a need to “bring the African narrative more firmly into relevant policy discussions” around the European Green Deal – a recent initiative to protect human health and restore damaged ecosystems. This includes plans to reduce use of the most hazardous pesticide types by 50% by 2030.
According to European Health and Food Safety commissioner Stella Kyriakides: “It is time to change course on how we use pesticides in the EU … We need to reduce the use of chemical pesticides to protect our soil, air and food, and ultimately the health of our citizens. For the first time, we will ban the use of pesticides in public gardens and playgrounds, ensuring that we are all far less exposed in our daily lives.”
According to a European Commission “Farm to Fork” policy document, EU scientific advisers have concluded that the current food system in Europe is no longer sustainable.
“This does not mean that pesticides are not needed. There are cases where satisfactory pest control can only be achieved in commercial food production through the use of chemical pesticides. However, chemical pesticides should be used only as a last resort.”
Rather than intensive pesticide use, the European Union promotes pest management systems where toxic chemicals are used only as a last resort. (Image: European Commission 2022)
The commission also cites a World Health Organisation report which estimates that there are about 1 million cases of unintentional pesticide poisonings every year, leading to approximately 20,000 deaths. A more recent review estimated about 385 million cases of unintentional acute pesticide poisonings occur annually worldwide, including around 11,000 fatalities.
Chemically active pesticides were found in up to 30% of European rivers and lakes, and regulators are worried about the increasing impact on the pollination of food crops at a time when up to 10% of bee and butterfly species in Europe are on the verge of extinction, and 33% are in decline.
Croplife SA has made it clear that it will push back against so-called EU “mirror clauses” that would prohibit South African farmers from using certain pesticides if they export products to Europe – even if these pesticides are legally registered in South Africa.
Global pesticide distributors have frequently been accused of double standards, by peddling in African and other developing countries agrochemical products that have been either banned or severely restricted in Europe because of human safety and environmental concerns.
Croplife SA, however, responds that enforcing European policies on local farmers is a “threat to the government’s right to make decisions for its people based on the local conditions and requirements”.
“Products cannot just be ‘dumped’ in South Africa as some activists claim; they must go through a rigorous registration process that considers the local production conditions and environmental impact.”
Croplife insists that the current regulatory framework in South Africa remains “robust” and “very strong” even though the original Act dates back to 1947.
But that is not how several other interest groups view the 1947 pesticides control law.
Precision farming techniques using drones or modifying the flow rate from spray nozzles can significantly reduce pesticide volumes compared to more conventional manual methods. (Photo: iStock)
Prof Leslie London, a senior University of Cape Town (UCT) public health research expert on pesticide hazards, chemical neurotoxicity and farm worker safety, says: “I think what Croplife really mean is that South Africa has a regulatory environment very favourable to industry. It would be laughable to consider it ‘strong’ unless you mean strongly biased to industry.”
He argues that at a time when many developed countries are adopting policies that promote pesticide reduction, South African policy remains largely out of step with international concerns
The primary 1947 law to control pesticides is regulated by the national Agriculture department, via the Registrar for Pesticides. But because this department is also mandated to promote agricultural expansion, Prof London believes this creates a clear conflict of interest concerning independent pesticide regulation.
He also suggests that the national department has done little to promote the Integrated Pest Management philosophy, which encourages farmers to reduce their reliance on chemical pesticides.
These are some of the alternatives proposed to reduce chemically-intensive farming. (Image: European Commission 2022)
In a journal critique published in 2000, Prof London and fellow UCT public health researcher Prof Hanna-Andrea Rother argued that pesticide regulation fines were “grossly inconsistent with the gravity of offences” while inspectorates were hugely understaffed.
Nearly a quarter of a century later, those derisory fines remain unchanged, and Prof London says that though there has been some “tinkering”, the current pesticide regulation model remains more or less unchanged.
He suggests that South Africa is still locked in a “pesticide culture” that sees intensive chemical control of farm pests as the norm, rather than as a last resort.
“This consent is manufactured by many forces, economic and ideological, and can be seen in the nature of pesticide advertising, and discourses surrounding the heroic role pesticides can play in economic development in the new South Africa,” according to the two researchers..
They noted that 100 to 200 cases of pesticide poisoning were reported every year to the Department of Health (mostly farmworkers or rural residents), while other surveys suggested that the true rates were anything between five and 20 times higher.
Several farm workers live in close proximity to crop fields sprayed from the air, potentially exposing them to toxic spray drift via contaminated air and water. (Photo: Professor Leslie London)
To resolve conflicts of interest and the fragmentation of regulation, the two researchers call for a new independent regulatory body to act as guardian of the public interest, separated from the economic motive to promote agricultural production.
Similar proposals for reform have also been made by Advocate Susannah Cowen SC on behalf of the Real Thing natural health products company.
In a legal opinion submitted to the SA Law Reform Commission in 2021, Cowen draws attention to the apparent double standards of South Africa importing hazardous chemicals from countries where these same chemicals are banned.
Cowen (now a judge of the labour court) said: “No amount of tinkering or amendment can render the 1947 Act fit for purpose in a democratic South Africa. It is wholly outdated.”
At the time of the submission, she said there was also no requirement for periodic safety reviews of currently registered pesticides or re-evaluations of old chemicals.
“The State made important reform commitments in the Pesticide Management Policy for South Africa in 2010. However, these commitments have not been realised and very little has been done since 2010 when these commitments were made.” DM
The Department of Agriculture Land Reform and Rural Development responds:
“The (1947) Act may only be amended once its relevance, applicability, suitability and responsiveness is under question, and so far the Act is still potently applicable
“Over the years, the department has phased out or banned many pesticides of concern under the same Act. We will continue to review the pesticides on concern, and where applicable we will phase out or ban them.
“There have been several regulations under the Act which the Minister has made in order to respond to some substantive recommendations which were part of the 2010 Pesticide Management Policy. The regulations relating to agricultural remedy, as published in Government Notice No. R. 3812 of August 2023, are aimed at addressing the recommendations of the 2010 Pesticide Management Policy.
“The latest regulations were published on 25 August 2023, which, among others, are aimed as phasing active ingredients and their pesticides formulations that potentially may cause cancer, genetic mutation and damages to fertility of a human being (including negatively affecting the unborn child); implementation of the Globally Harmonised System of classification and labelling of chemicals; restrictions of sale and use of certain hazardous pesticides, disclosure by agrochemical companies of amounts the of pesticides sold and other measures.
The Department of Forestry, Fisheries and the Environment (DFFE)responds:
A spokesperson said the department “categorically rejects [suggestions] that it has taken 20 years to implement the Rotterdam Convention. DFFE has been facilitating the exchange of information for more than 17 years (as far back as 2006).”
Commenting on the reasons for a recent series of notices to suspend, repeal or amend the convention’s domestic regulations, the department said it was compelled by law to undertake public participation when developing regulations.
“There were submissions on substantive matters that were submitted after the finalisation of the (Rotterdam) PIC Regulations that influenced the department to reconsider and opt for the suspension of the PIC Regulations. The department rejects claims or any perceptions of improper influence and maintains that the Batho Pele principles of consultation, courtesy and responsiveness remained at the centre of the department’s decision to suspend the regulations while the specific amendments were being attended to.”
Croplife South Africa responds:
Croplife confirmed that it made submissions to Creecy’s department to correct certain errors in the registration status of chemicals listed in the Rotterdam regulations.
Responding to criticism about the “double standards” of selling pesticides in Africa when they were banned in Europe or other developed nations, Croplife said: “It is quite normal for some countries to have plant protection solutions authorised for local use when they are not registered in other countries. Local climatic conditions, pest occurrence, crops and regulatory procedures differ from country to country. Therefore, products can be registered in one country and not in another.”
The industry group acknowledged that current laws only provide for a R1,000 fine for contraventions of the 1947 Act, but noted the government could impose much more severe sanctions – such as a banning or cancelling sales of certain chemical products.
There had also been “several” amendments since 1947, while specific product registrations were reviewed every three years.
New regulations published in August 2023 also contained a clause that a pesticide registration holder was obliged to inform the registrar of any new data pertaining to environmental or human toxicology
“Act No 36 and its supporting regulations provide a robust regulatory framework for plant protection solutions in South Africa. As with any government department, the Act No 36 of 1947 regulatory team could be more efficient if central Treasury provided greater funding. In this way, the approval and registration process could bring newer technologies to South African farmers more quickly.
“Government still has the overall right to approve or not approve a product. But our opinion remains that the system for product registrations can be more efficient, bringing newer technologies to farmers quicker, by better utilising the fees already paid to government for product registrations”.
I am pleased to announce that with the assistance of Dr. Nacro Souleymane of Burkina Faso and Matt Taylor of the IDENTIC group in Brisbane, Australia the French version of ”An illustrated key to the identification of selected West African rice insects and spiders” has been updated and is available online at the url below:
A funnel-weaving spider, Agelenopsis pennsylvanica, rests on its web while waiting out the rain.
Welcome to Pocket Science: a glimpse at recent research from Husker scientists and engineers. For those who want to quickly learn the “What,” “So what” and “Now what” of Husker research.
What?
The concept of urbanization rests on the population distribution of human beings, more than 50% of whom now live near large, often densely packed groups of other people. But the consequences of that urbanization — shifts in vegetation, localized fluctuations in temperature and wind, light and sound — can alter the distribution of other animals, too.
Given their limited lifespans, spiders and other arthropods must adapt more quickly than most, making them a valuable proxy for the ecological effects of urbanization. While hard data is hard to come by, arachnologists suspect that the global population of spiders — which eat up to 800 million metric tons of pests in a year — is now falling. Whether urbanization is contributing, and to what extent, remains a subject of some debate.
So what?
In search of factors that might sway the distribution and abundance of city-dwelling spiders, Nebraska’s Brandi Pessman and her colleagues turned to the wide-ranging species Agelenopsis pennsylvanica. The team sought out A. pennsylvanica in two areas of Lincoln: Nebraska U’s City Campus, considered an urban center, and Wilderness Park, an urban forest. As expected, the team found that those habitats differed in ways potentially relevant to the spiders. City Campus featured more artificial light, traffic and engineered surfaces — the latter contributing to higher temperatures — whereas Wilderness Park included more tree cover and plant diversity.
Pessman
A sampling expedition identified 131 funnel webs constructed by A. pennsylvanica, 64 of which brought forth spiders when the team stimulated the webs with a toothpick affixed to an electric toothbrush. City Campus boasted substantially more of those webs, and more spiders, than did Wilderness Park. Less distance separated the webs of the urban center than in the urban forest. And webs built on campus generally resided closer to the ground. Those findings suggest that differences between the urban environments could be motivating the real estate chosen by A. pennsylvanica, whose varied diet may help it adapt to human-disturbed areas that are less hospitable to pickier predators.
Yet the team also found that, even within City Campus, A. pennsylvanica webs were fewer and farther apart in spaces adjacent to roads or highways. The vibrations that propagate when rubber meets road might be to blame: Like many spider species, A. pennsylvanica relies on vibratory signals both to hunt and woo mates.
Now what?
Pessman is already conducting follow-up research on A. pennsylvanica in rural versus urban areas, hoping to determine whether environmental vibrations in the latter can limit the spider’s ability to detect prey. She’s also looking into whether the spider could be using webs to dampen disruptive frequencies.
Please note this request from Roma Gwynn of Biorationale Limited.
E A Heinrichs, IAPPS Sec. General and GPPN editor
“By means of this message, we invite you to fill out this (brief) online survey which aims to gauge in-country capacity and needs for biological control science, policy and practice. Supported by FAO’s Plant Production and Protection Division (NSP), the BiCCA toolkit has been specifically designed to pinpoint opportunities to advance biological control science, its commercial application and its ultimate farm-level implementation or scale-out. The survey focuses on the deployment of living organisms against target pests, weeds and pathogens in man-made or natural habitats, integrated as appropriate with compatible measures such as behavior-modifying semiochemicals, botanicals or microbial metabolites. The survey is structured modularly – completing any of its (4) constituent sections should take no longer than 10 minutes. We aim to have all survey responses in place by January 15, 2024.”
Note the 100 Euro discount for active IAPPS members on registration fees for the International Plant Protection Congress., 1-5 July 2024, Athens, Greece. For more information on the IPPC and to become an IAPPS member ($30 for students, $35 for developing countries and $50 for industrial countries) go to the IAPPS website http://www.plantprotection.org and click on the Join IAPPS icon. If you have a problem joining please contact me at eheinrichs2@unl.edu
E A (Short) Heinrichs, IAPPS Secretary General and Membership Manager
Registration Type
Until January 31st 2024
From February 1st 2024
Undergraduate Students*
290,00 €
390,00 €
PHD students* Post Doc Scientists* and Retired scientists**
Entomology Today posted: ” By Jacob A. Gorneau, Katherine O. Montana, and Lauren A. Esposito, Ph.D. Museum collections are libraries of the world’s biodiversity that hold stories about evolution, global change, and even disease or invasive species. Until recently, these ” Entomology TodayMarronoids: The (Mostly) Little Brown Spiders With a Big Story to TellEntomology Today Nov 30 A new study uncovers a clearer evolutionary tree for a broad group of spiders that previously proved difficult to classify—and illustrates the growing potential to extract useful genetic information from even the smallest of specimens in museum arthropod collections. Read more of this postCommentManage your email settings or unsubscribe. Trouble clicking? Copy and paste this URL into your browser: https://entomologytoday.org/2023/11/30/marronoid-spiders-genomic-sequencing-phylogeny/
Gilbert Barrantes / Laura Segura Hernández / Diego Solano Brenes
Gelanor siquirres, a species of pirate spider, descends from its dragline while pursuing prey in a Costa Rican rainforest.
Headlamps alone illuminated the trail bisecting the Costa Rican rainforest. Having waded the black of the Tirimbina reserve so often before, Gilbert Barrantes, Laura Segura Hernández and Diego Solano Brenes knew the routine.
It was time, dusk informed the surrounding spiders, to let loose the wind-aided, floating lines of silk that might latch onto leaf, branch or ground, fortifying the first beams of the food-snaring webs to come. But even on a night so familiar, the team would encounter a hunting scene unfamiliar not just to these arachnologists, in this forest, but all of them, anywhere.
“It was completely serendipitous,” said Segura Hernández, who earned her doctorate from the University of Nebraska–Lincoln in August.
What the trio stumbled on was a trap: lines floated not for framing but for fishing, part of a gambit that gives other forest-dwelling spiders just enough silk to hang themselves. And at the center of the scheme, not to mention the lines? A venomous pirate.
Four lines of that silk, the researchers realized, were running horizontally and diagonally from the underside of the same leaf. From elsewhere, the end of another thread had drifted in and caught on one of those leaf-dangling lines. That thread was the product of a spiderling now skittering along it to inspect the joint and, with its silken pillar secured, commence the construction of a full-fledged web.
“And then,” Segura Hernández said, “we just saw this other spider shoot in out of nowhere.”
The interloper was Gelanor siquirres, a species from the family known as pirate spiders — named for their willingness to invade already-built spider webs, strategically pluck threads to draw out their eight-legged inhabitants, and dine on them. This was something different. This G. siquirres emerged from its hiding spot beneath the leaf, scuttled across its own floating line, paralyzed its harried, hapless prey with a bite, then retreated to the leaf with the spiderling clutched in its ultra-long jaws.
A close look at that leaf would reveal the swashbuckler’s identity. A close look at the research literature would reveal that no one had ever reported the devious hunting technique, which the team has since witnessed multiple times. With a recent paper in the journal Animal Behaviour, the Tirimbina-trekking team would become the first.
“It’s working as a spider web for catching spiders,” Segura Hernández said of the lines floated by G. siquirres, which, like its pirate brethren, does not build circular webs. “That’s one of the cool things about it.”
Not the only thing, though. Pirate spiders are known as slow, deliberate killers: While venturing onto another spider’s web, Segura Hernández said, some pirates might advance no more than a few centimeters in an hour, lest they risk triggering any unwanted vibrations. The stealth makes sense when considering that the prey are also accomplished predators with venom of their own, and that G. siquirres, at no more than a half-inch long, is more David than Goliath.
Yet when another spider approaches one of its floating lines, G. siquirres darts forward with an alacrity that initially stunned Segura Hernández and her colleagues — the equivalent of a sloth turning cheetah.
“So it’s not just a modification of web-building behavior,” she said. “It’s a modification of the spider’s locomotion, as well.”
Footage of a pirate spider capturing a smaller arachnid before retreating to a leaf.
G. siquirres seems to have adapted its schedule, too, getting an early start to ensure that its floating lines are in place by the time its potential prey is releasing its own.
“It’s not like spiders make webs all night,” Segura Hernández said. “There’s clearly a peak period of activity, right after dark, where you see all of these floating lines on the trail. So it’s not like (G. siquirres) can do this in the morning. They are targeting this specific time period.”
There remains a lot to learn about G. siquirres, which was officially described and named in 2016 but had not, until now, been the subject of any peer-reviewed research. The fact that the first G. siquirres behavior ever documented happens to double as a behavior never seen in any spider speaks to how much remains unknown about the eight-legged wonders as a whole, Segura Hernández said, especially those residing in prey-rich rainforests.
G. siquirres feeding on its prey, an immature spider (white arrow) that touched the silk line its predator had earlier floated as a trap.
For her, it also underscores the value of not overlooking observation itself, of remembering to seek ideas, questions and answers not just in pages but the wild. She hasn’t forgotten the words of Bill Eberhard, who mentored her as an undergrad at the University of Costa Rica and was commemorated in the same journal issue that features the G. siquirres study.
“One of my favorite things about this paper is that it highlights how important it is — what Bill Eberhard taught us — to observe and just pay attention to detail,” she said. “Sometimes people are so focused on hypotheses and questions that they kind of forget about the organisms. But I think both things are equally important.
“Can we even envision how many more incredible hunting strategies there are just waiting to be observed?”
It was that spirit, in part, that encouraged her to spend so much time wandering in Tirimbina. At this point, she can’t recall any specific reason that she and the others were out that fateful night. Not that she needed one. The rainforest itself — the trill of insects and pattering of lizards, the aromas of wildflowers floating, like the spider silk, on a breeze — offered its own draw.
“Everything is alive. And at night, it has a mystery. You realize how much you rely on vision, because you’re restricted to what your headlamp can show.
“But that one time, we were just walking down the trail, talking about something,” she said, “and then we noticed the silk.”
Silk lines help pirate spiders trick, capture eight-legged prey ‘It’s working as a spider web for catching spiders’ Laura Segura Hernández and colleagues were venturing through a Costa Rican rainforest when they came along a spider — one about to unleash a hunting technique never before seen.
Bioprotection products are nature-based solutions to managing crop pests and diseases. More and more growers are turning to environmentally sustainable crop pest and disease management solutions, such as bioprotection products. Reasons for choosing more sustainable solutions include pest and disease resistance to chemical pesticides and concerns for human health and the environment.
Ladybird biological control. Image: CABI
Bioprotection products use living organisms such as insects (macrobials) and bacteria, viruses or fungi (microbials). They also include extracts or mimics of naturally occurring substances (semiochemicals).
What are the main types of bioprotection products?
Continue reading to discover the key product categories and how they can help manage crop pests and diseases.
Macrobial bioprotection products
Macrobial products include predator insects, parasitoid insects and nematodes. They all work slightly differently in killing pest insects.
Predator insects work to reduce pest numbers by attacking and feeding on other insects, usually killing several individuals during their life cycle.
Parasitoids
Parasitoid insects kill pest insects by inserting their eggs inside the bodies of pest insects. The eggs then develop and grow inside the body of the pest insect, killing it. The adult parasitoids then emerge from the bodies of the pest insects.
Entomopathogenic nematodes
Entomopathogenic nematodes are elongated, cylindrical worms of the order Nematoda. They are parasitic in animals, insects, or plants. They can also be free-living in soil or water. Nematodes kill pest insects by entering the body of the pest insect and infecting it with deadly bacteria. Some species of nematode reproduce within the body of the pest insect, with multiple nematodes exiting the body of the pest, ready to infect more pest insects.
Microbial bioprotection products
Microbial products include bacteria, viruses and fungi or other microorganisms or their metabolites or cell fragments that have the capacity to kill pests or outcompete and prevent diseases.
Bacteria are single-celled, microscopic organisms that lack a nucleus. When applied to crops, bacterial microbial products do not harm the crop itself. However, they are deadly to pest insects that eat the plant and become infected with the bacteria.
Viral products
Viruses are tiny, infectious particles consisting of nucleic acid and a protein coat, which can only reproduce within the cell of a living host. As with bacterial products, growers can apply viral products to crops without harm to the crop itself. When pest insects eat the plant, the insect becomes infected by the bacteria, causing the insect to die.
Fungal products
Fungi are multicellular organisms that lack chlorophyll and derive nutrients from other organisms. The fungal body generally consists of filamentous strands called mycelium. Fungal products usually work by landing on the body of the pest insect, with spores entering the body. The fungus branches and forms a network of branches inside the body of the insect, killing it. As well as destroying insects, microbial products kill plant-damaging diseases too.
Semiochemicals
Semiochemicals are message-bearing compounds produced by animals or plants that can be used to change and disrupt a pest’s normal behaviour (including sex and aggregation pheromones or various scented plant extracts that attract insect pests to traps).
CABI Academy Introduction to Bioprotection Products Course
Would you like to discover more about bioprotection products? The CABI Academy Introduction to Bioprotection Products course explains what they are, why they’re important and how they work. It gives a practical guide and set of resources to help advise farmers about choosing, using and interpreting the results of such products. The course is online and self-paced and takes approximately 8-10 hours to complete. Topics covered include:
– What are bioprotection products, and how do they work?
– Using bioprotection products to monitor pest insects
– Safety information and interpreting product labels
The CABI BioProtection Portal is an open-access tool that provides users with information about registered biocontrol and biopesticide products in their country. It aims to help growers and agricultural advisors identify, source and correctly apply these products against problematic pests in their crops.
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If you are active in the field of plant health or development and would like to contribute to the Plantwise Blog, please contact Donna Hutchinson. We are happy to post any credible articles that we think would be of interest to our readership.
Views expressed in contributions do not necessarily reflect official CABI or Plantwise positions.
The keys can also be accessed by going to – “Resources – Education and Training – Online identification keys for rice insect pests and natural enemies” on the IAPPS website http://www.plantprotection.org
Please note that we now have Google translate capabilities on the IAPPS website which provides translation in about 140 languages.
Entomology Today posted: ” By Jacob A. Gorneau, Katherine O. Montana, and Lauren A. Esposito, Ph.D. Museum collections are libraries of the world’s biodiversity that hold stories about evolution, global change, and even disease or invasive species. Until recently, these ” 
A new study uncovers a clearer evolutionary tree for a broad group of spiders that previously proved difficult to classify—and illustrates the growing potential to extract useful genetic information from even the smallest of specimens in museum arthropod collections. 
Global Plant Protection News 
