## Revue de presse / Recherche et medias

### L'impact d'une meilleure eau sur la consommation de pesticide

Chambres-agriculture Picardie 18/06/19

C'est un fait encore peu connu, mais la qualité de l'eau peut avoir un impact très important sur la consommation de pesticide par les agriculteurs. Malheureusement, ils ne sont pas très nombreux à le savoir et à y faire attention. Cela leur permettrait pourtant de faire des économies malgré quelques besoins d'entretien.

En contrôlant attentivement le pH de l'eau, il est possible de « préparer » l'eau pour qu'elle soit mieux adaptée au pesticide utilisé par l'agriculteur. Résultat, l'engrais utilisé pénètre mieux les plantes et il est possible de réduire sa consommation de moitié. Cela représente donc un avantage conséquent pour les agriculteurs, mais le procédé de préparation de l'eau reste complexe...

Cependant, certains militants écologistes refusent d'applaudir une telle innovation. Évidemment, ils encouragent le développement de solutions moins polluantes et moins dangereuses pour la santé. Néanmoins, ils rappellent que la transition vers une écologie plus respectueuse de l'environnement est nécessaire et que ce n'est pas seulement les pesticides qui posent problème. Il ne voudrait pas que cette nouvelle technique d'irrigation masque les problèmes posés par la monoculture intensive.

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### Prenatal pesticide exposure linked to changes in teen's brain activity

EurekAlert 27/08/19

Organophosphates are among the most commonly used classes of pesticides in the United States, despite mounting evidence linking prenatal exposure to the chemicals to poorer cognition and behavior problems in children.

A new study led by University of California, Berkeley, researchers is one of the first to use advanced brain

imaging to reveal how exposure to these chemicals in the womb changes brain activity.

The study, which appeared this week in the journal Proceedings of the National Academy of Sciences, used functional near-infrared imaging (fNIRS) to monitor blood flow in the brains of 95 teenagers born and raised in California's Salinas Valley, where agricultural spraying of pesticides is common.

Compared to their peers, teenagers estimated to have higher levels of prenatal exposure to organophosphates showed altered brain activity while performing tasks that require executive control, the study found.

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### Bad Blooms: Researchers review environmental conditions leading to harmful algae blooms

EurekAlert 26/08/19

When there is a combination of population increase, wastewater discharge, agricultural fertilization, and climate change, the cocktail is detrimental to humans and animals. This harmful cocktail produces harmful algal blooms, and many of these are toxic to humans and wildlife.

Wayne Wurtsbaugh, Professor Emeritus in the Watershed Sciences Department at Utah State University, along with Hans Paerl and Walter Dodds published a global review of conditions that lead to these harmful algal blooms in rivers, lakes, and coastal oceans. Wurtsbaugh says that the review will be an excellent resource for students studying pollution and for managers wanting to review recent advances in this field of study. Their review highlights how agricultural, urban, and industrial activities have greatly increased nitrogen and phosphorus pollution in freshwater and marine systems. This pollution has degraded water quality and biological resources costing societies billions of dollars in losses to fisheries, the safety of drinking water, increases to greenhouse gas emissions and related social values. Their findings have been published in, "Nutrients, eutrophication and harmful algal blooms along the freshwater to marine continuum."

https://onlinelibrary.wiley.com/doi/full/10.1002/wat 2.1373

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## Cleaning pollutants from water with pollen and spores - without the 'achoo!'

EurekAlert 26/08/19

In addition to their role in plant fertilization and reproduction, pollens and spores have another, hidden talent : With a simple treatment, these cheap, abundant and renewable grains can be converted into tiny sponge-like particles that can grab on to pollutants and remove them from water, scientists report. Even better, these treated particles don't trigger allergies.

The researchers will present their results today at the American Chemical Society (ACS) Fall 2019 National Meeting & Exposition. ACS, the world's largest scientific society, is holding the meeting here through Thursday. It features more than 9,500 presentations on a wide range of science topics.

A brand-new video on the research is available at www.acs.org/HLS_Pollen_Sponge.

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## New way to bump off ticks : Dry up their saliva (video)

EurekAlert 26/08/19

Saliva from a tick's bite can transmit pathogens that cause serious illnesses, such as Lyme disease, and significant agricultural losses. Current insecticides have drawbacks, so scientists have been seeking new ways to prevent these pesky arachnids from spreading pathogens. Now, researchers report that compounds they previously identified can dry up ticks' saliva by upsetting the balance of ions in the salivary gland, reducing feeding and potentially limiting pathogen transmission.

The researchers will present their results today at the American Chemical Society (ACS) Fall 2019 National Meeting & Exposition. ACS, the world's largest scientific society, is holding the meeting here through Thursday. It features more than 9,500 presentations on a wide range of science topics.

A brand-new video on the research is available at www.acs.org/HLS_Dry_Ticks.

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## New technique gives polyurethane waste a second life

EurekAlert 26/08/19

Polyurethane is used in a wide range of materials, including paints, foam mattresses, seat cushions and insulation. These diverse applications generate large amounts of waste. A team at the University of Illinois has developed a method to break down polyurethane waste and turn it into other useful products.

In the U.S. alone, 1.3 million tons of polyurethane waste is generated each year. The waste usually ends up in landfills or is incinerated, a process that requires a large energy input and generates toxic byproducts.

"We want to solve the waste problem by repurposing polyurethane," said Ephraim Morado, a graduate student in the laboratory of chemistry professor Steven Zimmerman, who led the research...

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## Physicians slow to use effective new antibiotics against superbugs

EurekAlert 26/08/19

New, more effective antibiotics are being prescribed in only about a quarter of infections by carbapenem-resistant Enterobacteriaceae (CRE), a family of the world's most intractable drug-resistant bacteria, according to an analysis by infectious disease and pharmaceutical scientists at the University of Pittsburgh School of Medicine and published today by the journal Open Forum Infectious Diseases.

This sluggish uptake of such high-priority antibiotics prompted the researchers to call for an examination of clinical and pharmaceutical stewardship practices across U.S. hospitals, as well as behavioral and economic factors, to see if the trend can be reversed before lackluster sales lead the pharmaceutical industry to stop developing much-needed antibiotics.

"The infectious diseases community spent the past decade saying, 'We need new antibiotics, this is a top priority,' and now we're at risk of sounding like the boy who cried wolf," said lead author Cornelius J. Clancy, M.D., associate professor of medicine and director of the mycology program and XDR Pathogen
Laboratory in Pitt's Division of Infectious Diseases. "We have a responsibility to learn why it takes so long for antibiotics to be adopted into practice and figure out what we need to do to ensure the best antibiotics quickly reach the patients who desperately need them."...

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## Urban stormwater could release contaminants to ground, surface waters

EurekAlert 21/08/19

A good rainstorm can make a city feel clean and revitalized. However, the substances that wash off of buildings, streets and sidewalks and down storm drains might not be so refreshing. Now, researchers reporting in ACS' Environmental Science & Technology have analyzed untreated urban stormwater from 50 rainstorms across the U.S., finding a wide variety of contaminants that could potentially harm aquatic organisms in surface waters and infiltrate ground water.

Previous studies of urban stormwater runoff have revealed a mixture of industrial chemicals, pesticides, pharmaceuticals and other substances that, at certain levels, can be toxic to aquatic life. As a result, many cities and water-management agencies are trying to develop stormwater control measures to minimize the transport of these contaminants to other water bodies, such as rivers or aquifers. However, data from a wide variety of locations across the U.S. are lacking. To help fill this research gap, Jason Masoner and colleagues wanted to catalog and quantify the contaminants in urban stormwater from 50 storm events at 21 sites across the nation....

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## Researchers reveal plant defense toolkit and insights for fighting crop diseases

EurekAlert 22/08/19

At an unprecedented scale, researchers have now catalogued the array of surveillance tools that plants use to detect disease-causing microbes across an entire species.

Representing a major advance for plant biology, the findings have important implications for the management of dangerous crop diseases which represent significant threats to food security.

Like animals, plants rely on immune systems to help them respond to attack by pathogenic microbes such as bacteria and fungi. A crucial layer of the immune system is formed by proteins called Nucleotide-binding Leucine-rich Repeat receptors (NLRs), which work together in combinations to detect the ever-changing array of microbes in the environment...

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## Understanding nitrogen removal processes from wastewater

EurekAlert 23/08/19

Increased demand for water also leads to an increase in wastewater production. Nitrogen compounds which accumulate in wastewater as by-products of human activity allow algae to grow in such aquatic environments. As demand for water exceeds the immediate supplies, there is a need to recycle wastewater to replenish water supplies in order to alleviate the burden of the water demand.

Edris Hoseinzadeh, through his recently edited book, Nitrogen Removal Processes for Wastewater Treatment, explains how nitrogen compounds can be easily and efficiently removed from wastewater. Hoseinzadeh reviews the nitrogen compounds that are chiefly found in wastewater, then explains different methods to remove these compounds. These methods include conventional methods (electrochemical methods, adsorption, ion exchange), biological methods (denitrification and the anammox process), and new bioelectrochemical techniques (microbial fuel cells and associated systems). The book also includes notes on factors that control these novel denitrification processes and operating parameters for practical application of these systems in wastewater treatment facilities.

Industrial and Environmental engineers as well as students learning about wastewater management and industrial denitrification will gain new knowledge in an environmental friendly perspective from the topics presented in this new book.

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## Could biological clocks in plants set the time for crop spraying ?

EurekAlert 16/08/19

Dr Antony Dodd, Senior Lecturer in the School of Biological Sciences and senior author of the paper, said: "This proof of concept research suggests that, in future, we might be able to refine the use of some chemicals that are used in agriculture by taking advantage of the biological clock in plants. Approaches of this type, combining biotechnology with precision agriculture, can provide economic and environmental benefits."

Just like human jet lag, plants have body clocks that are crucial for their life in a world that has day and night. Plant biological clocks make a crucial contribution to their growth and the responses of crops to their fluctuating environments.

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## Gene variant in maize ancestor could increase yields in today's densely planted fields

EurekAlert 15/08/19

From within the genetic diversity of wild teosinte - the evolutionary ancestor of modern maize - valuable traits lay hidden. In searching the ancestral genome, researchers report the discovery of UPA2, a rare allele long-lost to the selective pressures of domestication in modern maize, which can be used to directly increase the crop yields of densely planted maize by altering the angle of the plants leaves. "The work suggests that re-domesticating crops may identify other useful traits hidden in our crop's ancestors," writes Sarah Hake in a related Perspective. The ability to grow ever-increasing amounts of food to meet global demand relies on our ability to reap more from limited agricultural land. Increasing the density of planted crops can improve yields; however, for many crops, maize included, crowded plantings impose competition between plants for water, sunlight and soil nutrients. By adapting new varieties of maize with more upright leaves, the planting density of maize has been drastically increased. However, human selection comes at the cost of genetic diversity, which can limit the adaptive potential and genetic health of future generations. Recognizing the breadth of genetic variation within wild teosinte, Jinge Tian and

colleagues created recombinant inbred lines between modern maize and teosinte and revealed a molecular regulatory network controlling the UPA2 allele. According to the results, UPA2 confers upright and narrow plant growth in teosinte, but the gene is absent in maize. Introgression of the lost allele into modern maize resulted in hybrids with significantly increased yield under high-density planting, the authors say. ...

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## Climate change 'disrupts' local plant diversity, study reveals

EurekAlert 15/08/19

Faster rates of climate change could be increasing the diversity of plant species in many places, according to research from the University of York.

Researchers have discovered that the numbers of plant species recorded by botanists have increased in locations where the climate has changed most rapidly, and especially in relatively cold parts of the world.

Human activity has been responsible for substantial declines in biodiversity at the global level, to such an extent that there are calls to describe the modern epoch as 'The Anthropocene'. But although the total number of plant species on the planet may be in decline, the average number of plant species found locally - the so-called local or alpha diversity of a site - seems to be stable, or even increasing in places.

Scientists at the University of York think that the 'disruption' of these local plant communities by rapid climate change, especially changes in rainfall, may be allowing new species in and fuelling these local diversity increases.

The recent global assessment report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services* highlighted worrying declines in plants and animals around the world...

"We hope our study opens the door to a fuller understanding of how climate change is affecting plant communities, and what this means for the conservation of nature and its contribution to people".

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# Enriched environment in aquaculture enhances the survival of fish from bacterial disease

EurekAlert 15/08/19

Cooperative study conducted by University of Jyväskylä and Natural Resources institute Finland (Luke), revealed that enriched rearing of juvenile fish significantly enhances the survival of fish from bacterial infection commonly seen in rearing conditions. That may also improve the post release survival of the fish after stocking into the wild. The study has been published in Journal of Applied Ecology...

The results of the study may advance e.g. the development of natural disease prevention methods in aquaculture.

Link to publication:
https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.13393

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# Discovery could pave the way for disease-resistant rice crops

EurekAlert 15/08/19

Researchers have uncovered an unusual protein activity in rice that can be exploited to give crops an edge in the evolutionary arms race against rice blast disease, a major threat to rice production around the world.

Magnaporthe oryzae, the fungus that leads to rice blast disease, creates lesions on rice plants that reduce the yield and quality of grain. The fungus causes a loss of up to a third of the global rice harvest, roughly enough to feed more than 60 million people each year.

Various strategies to ward off the fungus have been employed, but a sustainable approach has not yet been developed. Cost and environmental concerns have limited the success of toxic fungicides. And a phenomena called linkage drag, where undesirable genes are transferred along with desired ones, has made it difficult for breeders to produce varieties of rice that exhibit improved disease resistance but still produce grain at a desired rate.

Gene-editing technologies could eventually be used to precisely insert genes in rice plants, overcoming the issue of linkage drag, but first, genes that boost rice immunity need to be identified or engineered.

DOI: 10.1074/jbc.RA119.007730

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# Princeton scientists awarded grant to boost crop yields by adding algal organelle to plant

EurekAlert 15/08/19

With world population projected to exceed eight billion people by 2025, food security is already a pressing global problem. Part of the solution will come from efforts to increase the yields of current food crops, but the global need for food only continues to grow, and could eventually outpace farmers' ability to increase production via conventional means such as breeding, application of fertilizers and improved land management. Martin Jonikas, an assistant professor in Princeton's Department of Molecular Biology, is collaborating with Alistair McCormick from the University of Edinburgh, Luke Mackinder from the University of York and Howard Griffiths from Cambridge University on a novel approach to boost crop productivity.

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# Early exposure to manganese could affect teens' cognitive ability and motor control

Early-life exposure to the mineral manganese disrupts the way different areas of the brain involved in cognitive ability and motor control connect in teenagers, Mount Sinai researchers report in a study published in PLOS ONE in August.

This study is the first to link evidence of metal exposure found in baby teeth to measures of brain connectivity. Researchers found links between early-life manganese exposure and altered functional connectivity of brain areas that support cognitive and motor control, potentially leading to low IQ, attention disorders, and hyperactivity...

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# Scientists find powerful potential weapon to overcome antibiotic resistance

EurekAlert 14/08/19

Staphylococcus aureus bacteria are a major cause of serious infections that often persist despite antibiotic treatment, but scientists at the UNC School of Medicine have now discovered a way to make these bacteria much more susceptible to some common antibiotics.

The scientists, in a study published in Cell Chemical Biology, found that adding molecules called rhamnolipids can make aminoglycoside antibiotics, such as tobramycin, hundreds of times more potent against S. aureus - including the strains that are otherwise very hard to kill. The rhamnolipids effectively loosen up the outer membranes of S. aureus cells so that aminoglycoside molecules can get into them more easily.

"There's a great need for new ways to kill bacteria that tolerate or resist standard antibiotics, and to that end we found that altering membrane permeability to induce aminoglycoside uptake is an extremely effective strategy against S. aureus," said study senior author Brian Conlon, PhD, an assistant professor in the department of microbiology and immunology at the UNC School of Medicine.

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# Microplastic drifting down with the snow

EurekAlert 14/08/19

Over the past several years, microplastic particles have repeatedly been detected in sea-water, drinking water, and even in animals. But these minute particles are also transported by the atmosphere and subsequently washed out of the air, especially by snow - and even in such remote regions as the Arctic and the Alps. This was demonstrated in a study conducted by experts at the Alfred Wegener Institute and a Swiss colleague, recently published in the journal Science Advances...

A team of experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) has now found that microplastic particles can apparently be transported over tremendous distances by the atmosphere and are later washed out of the

air by precipitation, particularly snow. As the team led by Dr Melanie Bergmann and Dr Gunnar Gerdts report in the journal Science Advances, the analyses they conducted on snow samples from Helgo-land, Bavaria, Bremen, the Swiss Alps and the Arctic confirm that the snow at all sites con-tained high concentrations of microplastic - even in remote reaches of the Arctic, on the is-land Svalbard, and in snow on drifting ice floes. "It's readily apparent that the majority of the microplastic in the snow comes from the air," says Melanie Bergmann. Her hypothesis is supported by past research conducted on grains of pollen, in which experts confirmed that pollen from the middle latitudes is transported by the air to the Arctic. These grains are rough-ly the same size as the microplastic particles ; similarly, dust from the Sahara can cover dis-tances of 3,500 km or more, reaching the northeast Atlantic...

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# Soils may reduce the impact of drought, or enhance damage

Peer 14/08/19

Tundra and natural forests in Northern Europe are more sensitive to extreme dry and hot climatic events than Mediterranean areas in Southern Europe. The soil plays an important role in determining the climate adaptability of these regions. A soil that has favourable growing conditions, strengthens plant resilience against heat and drought, but a soil with adverse conditions is contributing to the damage. This became clear from recent research by Wageningen University & Research.

The researchers show to which degree plants in Europe are affected by extreme drought and heat. They do this by determining the green index of plants with the use of satellite images. "The greenness of a plant can be seen as a degree of its productivity," explains Dr Titia Mulder, working at the Soil Geography and Landscape Group at WUR and first author of the recent scientific article. "Whenever greenness reduces in times of extreme heat and drought, this means that the plant is less productive and also damaged by the drought." The researchers analysed 26 years of monthly assembled data from remote sensing of the green cover by plants in the whole of Europe, between 1982 and 2008. These data have subsequently been linked to the monthly meteorological data...

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## Detention basins could catch more than stormwater

EurekAlert 12/08/19

Everywhere you go there are stormwater detention basins built near large construction projects intended to control the flow of rainwater and runoff. Now, those basins might help in controlling nitrogen runoff into rivers and lakes, according to Lauren E. McPhillips, assistant professor of civil and environmental engineering at Penn State.

Speaking today (Aug. 12) at the annual meeting of the Ecological Society of America in Louisville, Kentucky, she explained that she and colleagues at Cornell University looked at stormwater detention basins in the area around Ithaca, New York.

"Part of the goal for stormwater detention basins is to manage flow," said McPhillips. "Increasingly, we are trying to get more water quality goals out of them."

Controlling runoff from rain and trapping sediment has always been a goal of these ubiquitous basins, but new techniques may make them suitable for removing nitrate from the water as well. The basins the researchers examined are in urban and suburban areas, and nitrate comes from atmospheric deposition on roads, car combustion and lawn fertilizers.

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## Pollution : lumière sur la dégradation naturelle de la chlordécone

CEA 30/07/19

Des chercheurs du CEA-Jacob ont caractérisé en laboratoire une vingtaine de produits de transformation issus de la dégradation de la chlordécone (un Polluant Organique Persistant) et identifié ces mêmes produits dans les sols antillais, soulevant des questions quant à leur prise en charge en tant que nouveaux polluants potentiels.

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## Thyme essential oil in corn starch particles combats *Aedes aegypti* larvae

EurekAlert! 06/08/19

A system created in Brazil using cheap, biodegradable materials permits controlled release of larvicide and can be used in small amounts of water

Corn starch, an abundant, cheap and biodegradable raw material, is the basis for a novel larvicide developed by researchers at the University of Campinas (UNICAMP) in São Paulo State, Brazil. The material is used in microcapsules for storage and controlled release of active compounds to kill larvae of *Aedes aegypti*, the mosquito that transmits dengue, zika, yellow fever and chikungunya.

A patent application has been filed via UNICAMP's innovation agency (Inova). The methodology is described in an article published in Industrial Crops and Products.

The published paper describes a biodegradable controlled release system using thymol as the microencapsulated larvicide. Thymol, a key ingredient of essential oil derived from thyme (Thymus vulgaris), a plant widely used as a pharmaceutical and therapeutic agent, is also biodegradable and not harmful to humans in the concentration used by the researchers.

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## Magnetic 'springs' break down marine microplastic pollution

EurekAlert! 31/07/19

Plastic waste that finds its way into oceans and rivers poses a global environmental threat with damaging health consequences for animals, humans, and ecosystems. Now, using tiny coil-shaped carbon-based magnets, researchers in Australia have developed a new approach to purging water sources of the microplastics that pollute them without harming nearby microorganisms. Their work appears July 31 in the journal Matter.

"Microplastics adsorb organic and metal contaminants as they travel through water and release these hazardous substances into aquatic organisms when eaten, causing them to accumulate all the way up the food chain" says senior author Shaobin Wang, a professor of chemical engineering at the University of
Adelaide (Australia). "Carbon nanosprings are strong and stable enough to break these microplastics down into compounds that do not pose such a threat to the marine ecosystem."

To decompose the microplastics, the researchers had to generate short-lived chemicals called reactive oxygen species, which trigger chain reactions that chop the various long molecules that make up microplastics into tiny and harmless segments that dissolve in water. However, reactive oxygen species are often produced using heavy metals such as iron or cobalt, which are dangerous pollutants in their own right and thus unsuitable in an environmental context...

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## First pictures of enzyme that drives new class of antibiotics

EurekAlert! 31/07/19

Understanding how antibiotic scaffolds are constructed in nature can help scientists prospect for new classes of antibiotics through DNA sequencing and genome mining. Researchers have used this knowledge to help solve the X-ray crystal structure of the enzyme that makes obafluorin -- a broad spectrum antibiotic agent made by a fluorescent strain of soil bacteria. The new work from Washington University in St. Louis and the University at Buffalo is published July 31 in the journal Nature Communications.

A multi-part enzyme called a nonribosomal peptide synthetase produces the highly reactive beta-lactone ring that is responsible for obafluorin's antimicrobial activity.

"Obafluorin has a novel structure compared to all FDA-approved antibiotics," said Timothy Wencewicz, assistant professor of chemistry in Arts & Sciences. "In the long term, we really need new structural classes of antibiotics that have never been contaminated by clinical resistance from established antibiotic classes."

These chemicals could be used as next-generation antibiotics for humans, or even to benefit the agriculture sector, Wencewicz noted -- as researchers strive to engineer seed treatments and biopesticides to support plant systems capable of making enough food to feed the 9.6 billion people projected to live on this planet by 2050...

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## Study shows non-lethal impacts of seabirds' plastic ingestion

Eurekalert! 30/07/19

An IMAS-led study of seabirds that had ingested plastic debris has revealed a range of non-lethal impacts on their health and physiology...

The study led by IMAS' Dr Jennifer Lavers and published in the journal Environmental Science & Technology has found that plastic ingestion can have a significant negative impact even on superficially healthy seabirds...

"The complex range of issues that face seabirds - from habitat loss and climate change to fishing and marine pollution - make it vital that we better understand the impact of particular challenges such as plastic debris," Dr Lavers said.

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## Newly identified rice gene confers multiple-herbicide resistance

Eurekalert! 26/07/19

A rice gene that renders the crop resistant to several widely used beta-triketone herbicides has been identified, researchers report, revealing the genetic cause of herbicide susceptibility that has been identified in some important rice varieties. The newly discovered gene may be useful in breeding new herbicide-resistant crops. Rice is a staple food for more than 3.5 billion people and is among the world's most important crops. To meet the demands of the global food supply, the use of herbicides for controlling weeds is required for efficient crop production. While a useful herbicide is toxic to unwanted plants but harmless to the crop of interest, overuse of individual herbicides can lead to the emergence of weeds resistant to their once-deadly effects. Benzobicyclon (BBC), a beta-triketone herbicide developed for use in rice paddy fields, is effective against paddy weeds resistant to other herbicidal agents. However, BBC is also toxic to several high-yield rice varieties, according to the authors. To identify the gene responsible for BBC resistance or sensitivity, Hideo Maeda and colleagues performed map-based cloning on BBC-resistant and BBC-sensitive rice varieties, and they identified HIS1, a gene that confers resistance to BBC and other beta-triketone herbicides. According to Maeda et al., HIS1
encodes an oxidase that catalyzes and detoxifies BBC compounds. However, susceptible rice varieties inherited a dysfunctional his1 allele and harbor genetic mutations that disable expression of HIS1. What's more, similar functioning genes appear to be widely conserved in other important crop species, suggesting their potential value in breeding new herbicide-resistant crops.

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## Worm pheromones protect major crops

Eurekalert! 26/07/19

Protecting crops from pests and pathogens without using toxic pesticides has been a longtime goal of farmers. Researchers at Boyce Thompson Institute have found that compounds from an unlikely source - microscopic soil roundworms - could achieve this aim.

As described in research published in the May 2019 issue of Journal of Phytopathology, these compounds helped protect major crops from various pathogens, and thus have potential to save billions of dollars and increase agricultural sustainability around the world.

Led by BTI Senior Research Associate Murli Manohar, a team around Professors Daniel Klessig and Frank Schroeder investigated the effects of a roundworm metabolite called ascr#18 on plant health.

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## Low level exposure to air pollution is harmful, mouse model shows

Eurekalert 01/08/19

Scientists investigating the effect of air pollution on lung health have concluded that even low levels of exposure can have a detrimental effect on the lungs

Air pollution is made up of both gaseous and particulate matter (PM). Each year almost two million people die as a direct result of air pollution with many more experiencing impaired lung function, developing lung diseases such as asthma and chronic obstructive pulmonary disease (COPD). However research, on the effects of low level air pollution, is often overlooked...

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## High lead concentrations in amazonian wildlife

Eurekalert 05/08/19

It is in industrialised countries and regions of the world where one can find the highest concentrations of lead, the world's most widespread neurotoxical accumulative metal. Thus, it was presumed that the Amazon, the world's largest expanse of tropical rainforest containing the highest levels of biocultural and cultural diversity, would contain a low amount of urban or industrial contaminants due to its remoteness and low human impact.

A group of researchers from the Institute of Environmental Science and Technology and the Department of Animal Health and Anatomy at the Universitat Autònoma de Barcelona (ICTA-UAB), and the Central University of Catalonia/Vic University, for the first time have evaluated lead concentrations and isotopic fingerprints in free-ranging wildlife in remote areas of the Peruvian Amazon.

Finally, the study might be extended throughout the Amazonian ecosystem and other rainforests around the world, illustrating how human impact reaches further than usually envisaged, and the expansion of anthropogenic contaminants from industrial centres to the most remote areas of the planet.

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## Scientists propose environmentally friendly control practices for harmful tomato disease

Eurekalert 5/08/19

Tomato yellow leaf curl disease (TYLCD) caused by tomato yellow leaf curl virus-like viruses is the most destructive disease of tomato, causing severe damage to crops worldwide and resulting in high economic losses. To combat this disease, many farmers opt for intensive application of insecticides. However, this practice is frequently ineffective and has a negative impact on the environment and human health.

Alternatively, some farmers plant TYLCD-resistant tomato varieties, but these hybrid varieties are often tasteless and a poor comparison to the robust flavor of traditional tomatoes. As a result, there is a demand for effective and environmentally friendly
control measures to prevent continuing widespread
damage of TYLCD, as well as other plant viruses.

To answer this demand, a team of scientists at the Spanish Council of Scientific Research (IHSM UMA-CSIC) conducted field and greenhouse trials for three consecutive years and found two environmentally friendly control alternatives to insecticides.

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Pesticides deliver a one-two punch to honey bees

Eurekalert 05/08/19

Adjuvants are chemicals that are commonly added to plant protection products, such as pesticides, to help them spread, adhere to targets, disperse appropriately, or prevent drift, among other things. There was a widespread assumption that these additives would not cause a biological reaction after exposure, but a number of recent studies show that adjuvants can be toxic to ecosystems, and specific to this study, honey bees. Jinzhen Zhang and colleagues studied the effects on honey bees when adjuvants were co-applied at "normal concentration levels" with neonicotinoids. Their research, recently published in Environmental Toxicology and Chemistry, found that the mixture of the pesticide and the adjuvant increased the mortality rate of honey bees in the lab and in semi-field conditions, where it also reduced colony size and brooding.

When applied alone, the three pesticide adjuvants caused no significant, immediate toxicity to honeybees. However, when the pesticide acetamiprid was mixed with adjuvants and applied to honeybees in the laboratory, the toxicity was quite significant and immediate. In groups treated with combined pesticide-adjuvant concentrates, the mortality was significantly higher than the control groups, which included a blank control (no pesticide, no adjuvant, only water) and a control with only pesticide (no adjuvant). Further, flight intensity, colony intensity and pupae development continued to deteriorate long after the application comparative to the control groups...

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Phytosanitaires : une circulaire précise l'interdiction d'exporter des produits non autorisés en Europe

Actu-environnement 01/08/19

A partir de 2022, il sera interdit en France de produire, exporter et transporter des produits phytosanitaires non autorisés. Une circulaire organise l'application de cette mesure. Mais sa rédaction laisse des portes ouvertes.

A compter de 2022, il sera interdit de produire, exporter et transporter des produits phytosanitaires non autorisés en Europe pour des raisons liées à la protection de la santé ou de l'environnement. Une circulaire du 23 juillet organise cette interdiction.

Cette mesure est loin de faire l'unanimité. Adoptée dans le cadre de la loi Egalim, elle a été remise en cause lors de l'examen de la loi Pacte, ce printemps, avec le soutien du gouvernement (au motif de préserver des emplois)...

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