Bacterial electricity: Membrane potential influences antibiotic tolerance

Peer-Reviewed Publication

UNIVERSITY OF COLOGNE

The electrical potential across the bacterial cell envelope indicates when bacteria no longer operate as individual cells but as a collective. Researchers at the University of Cologne's Institute for Biological Physics have discovered this connection between the electrical properties and the lifestyle of bacteria. Although bacteria are single cellular organisms, they form spatially structured communities, so-called biofilms. Within biofilms, bacteria behave as a collective and can protect themselves better against external stresses like antibiotics. Until now, it was largely unknown how the transition from a single bacterium to such a complex community works. The researchers examined how the electrical properties of bacteria change during biofilm formation and discovered characteristic patterns of the electrical potential that evolve in space and time. These patterns correlated with the development of new habitats with varying degrees of tolerance to antibiotics. The researchers describe their findings in the article ‘Collective polarization dynamics in bacterial colonies signify the occurrence of distinct subpopulations’ in the Journal PLOS Biology.

Single bacteria build up an electric potential across their envelope (the membrane), and thus are electrically polarized. For the cell, this polarization is an important energy source for respiration, the uptake of nutrients and for the export of toxins. Recent methodological advances have enabled researchers to examine the dynamics of the membrane potential at the scale of single bacterial cells. These studies revealed that the membrane potential of single cells fluctuates independent of their neighbouring cells.

How does the potential change during biofilm development, and which environmental factors influence the potential? How does the potential relate to growth behaviour of cells and their tolerance to antibiotics? These questions have now been posed by a team of researchers at the Institute for Biological Physics led by Professor Berenike Maier. They examined early stages of biofilm formation of Neisseria gonorrhoeae (aka gonococcus), the causative agent of gonorrhoea, one of the most common sexually transmitted diseases, which can cause ectopic pregnancies and infertility. Within a few minutes, gonococci self-assemble into spherical colonies that comprise thousands of bacteria. “Using advanced light-microscopy and image analysis, we can measure the dynamics of the membrane potential of single cells in these colonies,” the first author Dr Marc Hennes explains. “The potential is uncorrelated within fresh colonies in bacteria. When the colony reaches a critical size, we observe something completely unexpected: All the cells in the centre suddenly increase their potential; they hyperpolarize.” Eventually, a shell of hyperpolarized cells occurs at the colony centre and travels through the colony. Behind this shell, the potential at the centre is lower. The researchers have interpreted this phenomenon of spatiotemporal correlated polarization patterns as the transition towards collective behaviour, indicative of biofilm formation. A combination of computer simulations and wet lab experiments showed strong evidence that this polarization pattern is linked to a change in the availability of oxygen. This pattern exists because cells at the centre deplete the oxygen faster than diffusion resupplies it.

An important question, therefore, was whether the pattern of membrane polarization correlated with the well-known functional heterogeneity of biofilms. Indeed, bacteria decreased their growth rate after they had gone through the process of hyperpolarization, whereas the growth rate of bacteria residing on the surface of the colony remained high. In addition, bacteria in the centre of the colony showed more tolerance towards antibiotics. Increased tolerance to antibiotics is an acute medical problem when treating biofilms. The molecular mechanisms of tolerance are the subject of a project funded by the Center for Molecular Medicine Cologne at the UoC.

The future goal is to better understand the molecular mechanisms that underlie the formation of polarization patterns and their relation to antibiotic tolerance. This research will be carried out within a new priority programme funded by the German Research Foundation (Deutsche Forschungsgemeinschaft).

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JOURNAL

PLoS Biology

DOI

10.1371/journal.pbio.3001960 

ARTICLE TITLE

Collective polarization dynamics in bacterial colonies signify the occurrence of distinct subpopulations

ARTICLE PUBLICATION DATE

18-Jan-2023

At least half of Africa's rhinos are now in private hands; New paths for rhino conservation are needed

Peer-Reviewed Publication

UNIVERSITY OF HELSINKI

 

IMAGE: WHITE RHINO ON A PRIVATE GAME RESERVE IN SOUTH AFRICA. view more 

CREDIT: IMAGE: HAYLEY CLEMENTS

African rhino numbers are declining at unsustainable rates in core state-run parks which is why more than half the continent's remaining rhinos are now on private land.

Until the past decade, the largest population of rhinos was found in South Africa’s Kruger National Park. This state-run park has, however, lost 76% and 68% of its white and black rhinos over the past decade, respectively. By contrast, the number of white rhinos on private land has steadily increased over the same decade, particularly in South Africa.

Private rhino owners now conserve at least half of the continents’ remaining rhinos, and communal lands conserve a growing proportion as well.

In a new article published in Frontiers in Ecology and the Environment, scientists from the University of Helsinki in Finland and the Universities of Stellenbosch and Nelson Mandela in South Africa have compiled publicly available rhino population data for African countries where rhinos occur, disaggregated by state, private, and communal land types where possible. They consider the implications of an emerging shift in rhino conservation from state to private and communal lands, and chart a new path for rhino conservation.

“Private and communal landowners in several southern and East African countries can generate revenues from wildlife tourism, trophy hunting and trade in live animals, making it financially viable to use their land to conserve wildlife rather than for farming livestock” explains paper author Dr Hayley Clements. “The result has been that hundreds of landowners conserve rhinos on their properties.”

But the cost-benefit ratio of conserving rhinos is changing, explains study co-author Dr Dave Balfour. “Accelerating poaching has meant private rhino owners now spend on average US$150,000 per year on security measures. This is far more than state parks are able to spend per rhino or per unit area conserved. Combined with the generally smaller size of private rhino populations (averaging 100 km2), which likely makes them easier to protect than in places like Kruger (20,000 km2), this spending on security means private rhino populations have suffered lower poaching rates than in some core state-run parks. But these rising security costs mean many landowners are not willing or able to continue conserving rhinos, with some choosing to sell their rhinos, often at a loss.”

“It is important that future policy enables new incentives that compensate for rising security costs, encouraging rhino conservation on private and communal land”, explains senior author Prof. Enrico Di Minin. “For example, could landowners that conserve rhinos in extensive systems qualify for a more favourable tax structure? Could they be eligible for carbon or the emerging biodiversity credits or rhino bonds, given the role of rhinos in carbon cycling? Could they receive certifications for extensive management that increase the value of their wildlife-based tourism and hunting offerings? These are crucial questions that need to be addressed in order to support more sustainable conservation strategies for rhinos”, he continues.

“If additional incentives are not enabled, we risk losing private and communal rhino custodians, and with them, half of the remaining African rhinos” concludes Dr Clements.

Moreover, increased transparency by states about rhino numbers and their management is critical for understanding where and how best to conserve them. Availability of up-to-date data on rhino populations, poaching rates, and security costs can aid in identifying and quantifying long-term trends in rhino populations across land tenure types, inform their conservation, and help raise public awareness and support.

More information:

Email: environ1@mweb.co.za

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JOURNAL

Frontiers in Ecology and the Environment

DOI

10.1002/fee.2593 

METHOD OF RESEARCH

Systematic review

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Importance of private and communal lands to sustainable conservation of Africa's rhinoceroses.

New research quantifies the ‘wow’ factor of sunrise and sunset for the first time

A new study has identified the impact that fleeting natural events, such as sunrises and sunsets, can have on people, and sought to quantify their effects for the first time

Peer-Reviewed Publication

UNIVERSITY OF EXETER

 

IMAGE: DIGITAL SUNSET FEATURED IN RESEARCH STUDY view more 

CREDIT: UNIVERSITY OF EXETER

A new study has identified the impact that fleeting natural events, such as sunrises and sunsets, can have on people, and sought to quantify their effects for the first time.

Despite a large body of research examining the impacts of nature on our mental health, most studies have assessed these effects under calm, blue skies. Surprisingly few have considered how we respond to variations in weather and the daily rhythms of the sun, changes referred to as ‘ephemeral phenomena’.

To help close this gap, researchers used the latest computer graphics to show carefully controlled images of both urban and natural environments to more than 2,500 participants. When these scenes featured elements such as sunrise and sunset, participants considered them to be substantially more beautiful than when seen under sunny conditions at any other time of day.

Unexpectedly, the paper revealed that sunrise and sunset could also trigger significant boosts in people’s feelings of awe. A typically difficult emotion to elicit, research indicates that awe has the potential to improve mood, enhance positive social behaviour, and increase positive emotions – all valuable factors in enhancing overall wellbeing.

Published in the Journal of Environmental Psychology, the paper also considered rarer events, such as rainbows, thunderstorms, and starry, moonlit skies in the experiment. Each of these phenomena altered the extent to which people experienced beauty and awe in different landscapes, when compared to sunny, blue skies.

Crucially, these changes were also behind variations in how the environments were valued – assessed by asking participants how much they would be willing to pay to experience each scene in the real world.

Sunrise image as used in research study

CREDIT

University of Exeter

Participants were prepared to pay a premium of almost 10 per cent to visit a natural setting at sunrise compared to under blue skies. The research team said this kind of added value is normally attributed to more permanent features, such as scenic lakes or historic buildings. They suggested that encouraging people to experience sunsets and sunrises could help boost wellbeing, and might be used as part of green prescribing, where nature plays a therapeutic role in mental health treatment.

Alex Smalley, PhD fellow at the University of Exeter and lead author of the research, said: “We’re all familiar with the urge to take a photo of a brilliant sunset or unexpected rainbow. The term ‘sunset’ has over 300 million tags on Instagram and people told us they’d be willing to pay a premium to experience these phenomena, but of course we can all experience them for free. Our research indicates that getting up a bit earlier for sunrise or timing a walk to catch sunset could be well worth the effort – the ‘wow’ factor associated with these encounters might unlock small but significant bumps in feelings of beauty and awe, which could in turn have positive impacts for mental wellbeing.”

The authors also noted how the occurrence of the phenomena they tested could vary greatly based on where people live. Those on east-facing coastlines might find sunrise easier to see, whilst those in the west might more frequently experience sunset. Equally, thunderstorms may be more common in summer in the UK, yet rainbows appear more often in winter. Alex Smalley added: “Most of the phenomena we tested can be fleeting and unpredictable, and we think this novelty is partly behind the effects we’re seeing. Given their potential to change people’s experiences in both natural and urban landscapes, there could be real value in highlighting how and where these events might be experienced, particularly in towns and cities.”

The paper, titled Beyond blue-sky thinking: Diurnal patterns and ephemeral meteorological phenomena impact appraisals of beauty, awe, and value in urban and natural landscapes, is published today in the Journal of Environmental Psychology. 

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JOURNAL

Journal of Environmental Psychology

DOI

10.1016/j.jenvp.2023.101955 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Beyond blue-sky thinking: Diurnal patterns and ephemeral meteorological phenomena impact appraisals of beauty, awe, and value in urban and natural landscapes

ARTICLE PUBLICATION DATE

19-Jan-2023

Low-impact human recreation changes wildlife behavior

Peer-Reviewed Publication

WASHINGTON STATE UNIVERSITY

 

IMAGE: RESEARCHERS PLACED CAMERA TRAPS ALONG HIKING TRAILS IN GLACIER NATIONAL PARK AND FOUND THAT 16 OUT OF 22 SPECIES CHANGED THE WAY THEY ACCESSED AREAS WHEN HUMANS WERE PRESENT. ONLY ONE SPECIES RED FOX WERE MORE PRESENT ON AND NEAR TRAILS WHEN THE PARK WAS OPEN–PERHAPS BECAUSE THEIR COMPETITORS, COYOTES, AVOIDED THOSE AREAS WHEN HUMANS WERE AROUND. view more 

CREDIT: MAMMAL SPATIAL ECOLOGY AND CONSERVATION LAB, WASHINGTON STATE UNIVERSITY

PULLMAN, Wash. – Even without hunting rifles, humans appear to have a strong negative influence on the movement of wildlife. A study of Glacier National Park hiking trails during and after a COVID-19 closure adds evidence to the theory that humans can create a “landscape of fear” like other apex predators, changing how species use an area simply with their presence.

Washington State University and National Park Service researchers found that when human hikers were present, 16 out of 22 mammal species, including predators and prey alike, changed where and when they accessed areas. Some completely abandoned places they previously used, others used them less frequently, and some shifted to more nocturnal activities to avoid humans.

“When the park was open to the public, and there were a lot of hikers and recreators using the area, we saw a bunch of changes in how animals were using that same area,” said Daniel Thornton, WSU wildlife ecologist and senior author on the study published in the journal Scientific Reports. “The surprising thing is that there’s no other real human disturbance out there because Glacier is such a highly protected national park, so these responses really are being driven by human presence and human noise.”

The researchers had also expected to find an effect known as “human shielding,” when human presence causes large predators to avoid an area, providing opportunity for smaller predators and perhaps some prey species to use an area more frequently. In this case, they found this potential effect for only one species, red fox. The foxes were more present on and near trails when the park was open–perhaps because their competitors, coyotes, avoided those areas when humans were around.

Several species showed a decline in use of trail areas when the park was open, including black bear, elk and white-tailed deer. Many decreased their day-time activities, including mule deer, snowshoe hare, grizzly bears and coyotes. A few, including cougars, seemed indifferent to human presence.

While the influence of low-impact recreation is concerning, the researchers emphasized that more research is needed to determine if it has negative effects on the species’ survival.

“This study does not say that hiking is necessarily bad for wildlife, but it does have some impacts on spatiotemporal ecology, or how wildlife uses a landscape and when,” said Alissa Anderson, a resent WSU master’s graduate and first author on the study. “Maybe they are not on the trails as much, but they're using different places, and how much does that actually impact species’ ability to survive and thrive in a place, or not? There are a lot of questions about how this actually plays into population survival.”

The study came about in part because of the pandemic. Both humans and wildlife like to use trails, so the researchers had set up an array of camera traps near several trails to study lynx populations in Glacier National Park when COVID-19 hit. In an effort to keep the virus from spreading to the nearby Blackfeet Indian Reservation, the eastern portion of the park was closed in 2020 with only minimal access allowed to administrators and researchers.

This allowed Anderson, Thornton and co-author John Waller of Glacier National Park to conduct a natural experiment. They captured images in summer of 2020 when the park was closed as well as in 2021 when it opened again.

Glacier, which covers nearly 1,600 square-miles of northwestern Montana, sees more than 3 million human visitors a year. It is also home to diverse range of animals with almost the full complement of mammal species that has existed in the region historically.

Thornton said park managers are faced with a balancing act between conservation and public use missions.

“It's obviously important that people are able to get out there, but there might be a level of which that starts to be problematic,” he said. “Some additional research could help get a better understanding of that and help develop some guidelines and goals.”

This study received support from the Glacier National Park Conservancy and the U.S. Department of Agriculture.

Researchers placed camera traps along hiking trails in Glacier National Park during and after a COVID-19 closure. They found that 16 out of 22 mammal species changed the way they accessed areas when humans were present. Only a few species, including cougars, seemed indifferent to human presence.

CREDIT

Mammal Spatial Ecology and Conservation Lab, Washington State University

JOURNAL

Scientific Reports

DOI

10.1038/s41598-023-27670-9 

ARTICLE TITLE

Partial COVID-19 closure of a national park reveals negative influence of low-impact recreation on wildlife spatiotemporal ecology

 Active matter theory explains fire-ant group behavior

The fire ant as a model in physics

Peer-Reviewed Publication

UNIVERSITY OF BARCELONA

 

IMAGE: FROM LEFT TO RIGHT, THE EXPERTS CALEB ANDERSON AND ALBERTO FERNÁNDEZ-NIEVES. view more 

CREDIT: UNIVERSITY OF BARCELONA

Ants are social insects and the Solenopsis invicta species —known as the fire ant— is no exception. The social interactions of this invasive insect, which comes from South America, are framed within the context of the theory of Active Matter, which would explain the ants’ group behaviour as a reaction to the intrinsic mechanisms in the system. This is one of the conclusions of the article published in the journal Science Advances by researchers Alberto Fernández-Nieves and Caleb Anderson, from the Faculty of Physics of the University of Barcelona, and Guillermo Goldsztein, from the Georgia Institute of Technology (United States).

 

The study reveals that density is essential for the ants to experience activity cycles and undergo periods in which the group of insects moves collectively. Under conditions of high density, these activity cycles are displayed in a surprising way when the ant community is organized into a vertical column, creating activity waves that propagate upwards.

The fire ant as a model in physics

The fire ant, a hymenopteran with a high reproductive and dispersal ability, has been used as a reference model for studying active systems at high density. Under different conditions, the ant collective experiences what is known as activity cycles: the group of ants changes back and forth from a situation where many ants are stationary, to a situation in which practically all the ants are moving.

“Studying dense active systems in a lab is not trivial. From a physical perspective, ants are considered active particles that use chemical energy to move. They can be easily concentrated to create a dense collective that we can use to address active matter questions”, notes Alberto Fernández-Nieves, ICREA professor at the Department of Condensed Matter Physics and the UB Institute of Complex Systems (UBICS).

Active matter, specifically, is based on particles that can self-propel, and that as a result, move due to local consumption of energy, unlike atomic or colloidal systems, whose constituents move as a result of temperature.

From social attraction to collective behavior

There are two large behaviours that emerge in active matter: the first is the transition into a state in which the set of particles moves in the same direction (collective mode), a behaviour usually related to bird flocks and fish schools. The other manifests when the motility of the particles decreases with their pair-separation distance. In this case, as the particles get closer, they stop moving, a result that can be understood as an attraction between them. Under certain conditions, this attraction can lead to the formation of aggregates, and in some cases, to the separation of a phase formed by stationary ants and a phase formed by moving ants.

According to the study, density is crucial for the ant collective to change between these behaviours. “With a lower density, the phase we observe is that related to social attractions”, the authors say. “Changes to the collective motion phase are seen only when the density is high enough. This explains why the waves are always generated near the base of the ant columns, where the density is higher”.

The study states that the ants’ social attraction —i.e. their interaction— can be explained as an induced phenomenon due to a declining motility with ant-ant separation. However, at high densities, this attraction disappears and the ant community adopts a collective group mode that results in the activity waves that propagate upwards.

“These density and activity waves reflect that the states of the activity cycles in which all the ants are moving correspond to a collective phase, which is similar to the described organized phase, for instance, in flocks of birds, schools of fish or groups (packs or herds) of animals”, the experts note.

Ants’ collective mode in the environment

In nature, the collective mode of fire ants can be seen under different conditions. These insects, which come from an area with abundant rainfalls and floods, have evolved to overcome these extreme episodes through these activity cycles.

“In order to survive these phenomena, fire ants build rafts in which all individuals cluster together; therefore, the density of the raft is high. According to previous studies, when they are in the rafts, the ants undergo inactive periods where the shape of the raft is circular, and others in which there is more movement. In this last case, the shape of the raft becomes characterized by the formation of collective protrusions with finger-like shape”, the authors note.

During the inactive periods, the raft would behave as an elastic solid, which helps resist the impact of objects that are washed away by the rain. At the same time, the formation of the finger-like shape, allows the ants to search for solid ground. If they find it, they migrate to land, and if they don’t, they group together again and continue these cycles from time to time until they do.

“Therefore, we think that periods with movement that involve the formation of fingers are similar to the collective mode we observe in our experiments and which generates the ant waves in the vertical columns”, conclude the authors.

Active matter and nonequilibrium systems

The variations in ant aggregation state have implications in the material properties. The authors explained that in previous studies, they “found that the mechanical properties changed drastically depending on the state of the ant collective. In attraction-dominated phases, the behaviour was similar to that of an elastic solid. In contrast, in active phases, the community reorganizes itself at the particle level to somewhat flow as a liquid”.

“If analysed as an active material, the ant community can change the mechanical behaviour through changes in their activity. In material science, this is typically achieved by changing the structure of the material. In the case of ants, this can occur by being far from equilibrium. The solid-to-liquid transition is a result of internal mechanisms that bring the system out-of-equilibrium and that reminds of the activity of active matter particles. There are no relevant structural changes; the dense ant communities are always disordered. This behaviour reminds us of the character in the film Terminator, who spontaneously changes from liquid to solid. In this sense, and despite its complexity, the Terminator in the film is also active mater”, conclude the researchers.

 

 

 

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JOURNAL

Science Advances

DOI

10.1126/sciadv.add0635 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Ant Waves – Spontaneous activity waves in fire-ant columns

ARTICLE PUBLICATION DATE

18-Jan-2023

Nottingham professor’s Fellowship will analyse impacts of world issues on UK regions

Grant and Award Announcement

UNIVERSITY OF NOTTINGHAM

Financial geography expert, Professor Sarah Hall, of the University of Nottingham, has been appointed as Senior Fellow at the think tank UK in a Changing Europe (UKICE).

Professor Hall’s fellowship will analyse the uneven nature of the economy across UK regions and how they are impacted by significant global economic changes. Professor Hall will analyse policy interventions aimed at supporting local economies, including today’s announcement regarding the second round of funding from the government’s levelling up fund.

Her research will examine a number of locations, including Mansfield (Nottinghamshire), Belfast and Teesside to understand how firms and households are responding to changes in the UK economy such as Brexit and the cost of living crisis.

Professor Hall has also been appointed as Deputy Director of UKICE, where she intends to expand the organisation’s connections to the wider social scientific communities and policy audiences.

Dr Sarah Hall, Professor of Economic Geography in the School of Geography at the University of Nottingham said: “We know that the UK economy is being affected by a number of changes: the post-Brexit UK-EU trading relationship and the UK’s evolving trade strategy with other countries; changes in global supply chains, partly related to Brexit but also shaped by the ongoing Covid economic recovery; energy price shocks related to the war in Ukraine; and political commitments to deliver a net zero economy by 2050.

“The implications of these geopolitical changes for the UK economy are often the source of intense public and political debate. This Fellowship will provide impartial, accessible knowledge about these issues, grounded in social scientific research that is accessible to policy makers, businesses and the wider public.

“Given the fact that the UK has been identified as the most uneven national economy within the G7, and the Government is committed to a policy of ‘levelling up’, it is particularly important that such analysis includes regional and local scale analysis.”

The project will include real-time data tracking of UK local and regional economic performance through a dashboard called TracktheEconomy, which was initially developed by colleagues in the School of Economics at the University of Nottingham along with Professor Hall to chart local economy performance during the Covid-19 lockdowns. She has subsequently worked with colleagues at the university’s Centre for Inclusive Financial Technology (INFINITY) to launch a report entitled Levelling up: Designing policy to fit places, developing a machine-learned statistical model of the economic geography of the UK.

The TracktheEconomy data will support in-depth analysis of five locations across the UK selected to include a range of economic sectors, political, institutional and regulatory settings:  

• Belfast in order to address the economic impacts of the Northern Ireland Protocol, which was brought in after Brexit to allow goods to be transported across the Irish border without the need for checks.
• Mansfield in order to understand a deindustrialised town which voted 71 per cent to leave in the Brexit referendum and has received Towns fund funding
• Milton Keynes in order to understand one of the UK’s fastest growing cities with areas of slower economic growth that have received levelling up funding and narrowly voted leave in the Brexit referendum
• Teesside in order to understand a deindustrialised locality with a local mayor, that voted leave and has been the recipient of considerable policy intervention subsequently including the Treasury campus in Darlington and the creation of a freeport
• London in order to understand changes in the services sector, particularly financial services which has been identified as an important sector in which Brexit dividends may be derived from regulatory change, as well as being a local economy which is currently outperforming the UK nationally.

Professor Neil Crout, Pro Vice-Chancellor for Research and Knowledge Exchange at the University of Nottingham, said: “This is fantastic news for Professor Hall and builds on the university’s research strengths in studying economic activity - an area which is clearly impacting so many people in the UK. This Fellowship could not be better timed, given today’s news of more levelling up funding being allocated to projects across the UK. Only with the latest data can the right judgments be made about where to allocate support and funding to help the UK economy to grow and improve inequality in UK regions.”

The news comes as the UK in a Changing Europe announces it is entering a new phase, with renewed funding and an expanded team and agenda, focussed on three broad themes:

• UK-EU relations,
• The UK after Brexit,
• The UK’s place in the world.

As part of this relaunch, the Economic and Social Research Council (ESRC) has appointed ten new UKICE Senior Fellows. The new team of academics will contribute to UKICE’s programme of work by producing high-quality original research, and communicating it to policymakers, politicians, the media, and the general public.

Study explores control options for black swallowwort

Peer-Reviewed Publication

CAMBRIDGE UNIVERSITY PRESS

 

IMAGE: BLACK SWALLOWWORT, LIKE MANY INVASIVE SPECIES, IS DIFFICULT TO MANAGE, SO VARIOUS TOOLS LIKE HERBICIDES NEED TO BE ASSESSED TO PROVIDE LAND MANAGERS EFFECTIVE OPTIONS FOR THEIR PARTICULAR SITUATION. view more 

CREDIT: JEROMY BIAZZO

WESTMINSTER, Colorado – 19 January, 2023 – Black swallowwort is a difficult to control invasive vine that thrives in natural areas and perennial cropping systems across northeastern North America. To date, though, no scientific studies have been conducted to determine how the weed responds to common controls, such as mowing and broad-spectrum herbicides.

In an article featured in volume 15, issue 4 of the journal Invasive Plant Science and Management, researchers describe a three-year field study that begins to fill this information gap.

The team explored how black swallowwort responded to two glyphosate products and one triclopyr product. The weeds were either sprayed annually with a two percent solution of one the herbicides at flowering in early July – or were mowed in early July and then treated in late August.

The study showed the two glyphosate formulations were effective in reducing aboveground black swallowwort biomass, but they were less effective in reducing cover and stem densities. Researchers also determined that mowing failed to enhance the efficacy of the glyphosate applications on a consistent basis.

Triclopyr was generally ineffective in controlling black swallowwort – whether with or without mowing. The only significant effect of the herbicide was to increase grass cover in the test plots.

“Our study shows annual applications of glyphosate can be useful in managing infestations of black swallowwort vine,” says Lindsey Milbrath of the USDA’s Agricultural Research Service. “Further investigation will be needed to determine whether higher rates and more frequent applications of triclopyr can also deliver effective control.”

To learn more, visit the open access article here: “Response of Black Swallowwort (Vincetoxicum nigrum) to herbicides plus mowing”

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JOURNAL

Invasive Plant Science and Management

DOI

10.1017/inp.2022.27 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Response of black swallowwort (Vincetoxicum nigrum) to herbicides plus mowing

Aston University partners with energy technology company and University of Nairobi to improve crop production in Kenya by up to 50%

Business Announcement

ASTON UNIVERSITY

 

IMAGE: ASTON UNIVERSITY PARTNERS WITH ENERGY TECHNOLOGY COMPANY AND UNIVERSITY OF NAIROBI TO IMPROVE CROP PRODUCTION IN KENYA BY UP TO 50% view more 

CREDIT: ASTON UNIVERSITY

• Aston University enters 15-month knowledge transfer partnership with Solargen Technologies and the University of Nairobi to develop irrigation system powered by solar and wind energy
• Crop yields will increase by 30 to 50% using control and sensor systems to deliver optimised amount of water for soil conditions
• Results of the collaboration will support farmers in Kenya and increase company revenue by 77%

 

18 January 2023 | Birmingham, UK

Aston University has teamed up with engineering company Solargen Technologies (SGT) and the University of Nairobi through a Knowledge Transfer Partnership (KTP) to develop a smart irrigation system using solar and wind energy to provide year-round watering of land to improve crop production in Kenya.

A KTP is a three-way collaboration between a business, an academic partner and a highly qualified researcher, known as a KTP associate.

SGT is a leading energy, water and irrigation solution and service provider in Kenya. They work in partnership with non-governmental entities, government, and individuals to serve communities in rural and conflict-affected parts of Eastern Africa through customised solutions that meet their energy, water and food security needs.

Kenya's economy is agriculture-based, but over 80% of its land is dry. Farmers cannot depend on rain-fed agriculture due to unpredictable rainfall and frequent drought, therefore an irrigation system is required. SGT’s current irrigation system is solar powered and requires large batteries and manned operation to maintain efficiency, resulting in high operating and maintenance costs and issues with performance during cloudy days.

This KTP will use a hybrid source of solar and wind energy to power ‘smart sensors’ and ‘control systems' to automatically deliver the right amount of water for a given crop type and maintain the required soil moisture level, resulting in increased crop yields.

The Aston University team will be led by Dr Muhammed Imran, senior lecturer in mechanical engineering and an established researcher in the area of renewable energy systems, especially hybrid energy systems. He will be supported by Dr Tabbi Wilberforce Awotwe, lecturer in mechanical engineering and design and an established researcher in the area of sustainable energy systems and optimisation approaches.

Dr Imran said: “We are delighted to design the hybrid solar and wind energy system for this smart irrigation system, which will have a positive impact on primary crop production, increase the availability of safe and healthy foods and improve the welfare of farmers and their families in rural Kenya.”

They are collaborating with Professor Ayub Gitau and Dr George Kamucha from the University of Nairobi. Professor Gitau is an associate professor and dean for the School of Engineering and a professional agricultural engineer. Dr Kamucha is a senior lecturer and chairman for the Department of Electrical and Information Engineering who has extensive experience in advance control systems as well as advance model predictive control systems.

Badr Shariff, managing director at Solargen Technologies, said: “The project will bring together Aston University’s expertise in hybrid energy, the University of Nairobi’s expertise in irrigation systems and our expertise in system integration and solar energy to develop a market leading irrigation system with increased reliability and low operating and maintenance costs.”

ENDS