One of the world’s most widely used glyphosate-based herbicides, Roundup, can trigger loss of biodiversity, making ecosystems more vulnerable to pollution and climate change, say researchers from McGill University.
The widespread use of Roundup on farms has sparked concerns over potential health and environmental effects globally. Since the 1990s use of the herbicide boomed, as the farming industry adopted “Roundup Ready” genetically modified crop seeds that are resistant to the herbicide. “Farmers spray their corn and soy fields to eliminate weeds and boost production, but this has led to glyphosate leaching into the surrounding environment. In Quebec, for example, traces of glyphosate have been found in Montérégie rivers,” says Andrew Gonzalez, a McGill biology professor and Liber Ero Chair in Conservation Biology.
To test how freshwater ecosystems respond to environmental contamination by glyphosate, researchers used experimental ponds to expose phytoplankton communities (algae) to the herbicide. “These tiny species at the bottom of the food chain play an important role in the balance of a lake’s ecosystem and are a key source of food for microscopic animals. Our experiments allow us to observe, in real time, how algae can acquire resistance to glyphosate in freshwater ecosystems,” says post-doctoral researcher Vincent Fugère.
Ecosystems adapt but at the cost of biodiversity
The researchers found that freshwater ecosystems that experience moderate contamination from the herbicide became more resistant when later exposed to a very high level of it – working as a form of “evolutionary vaccination.” According to the researchers, the results are consistent with what scientists call “evolutionary rescue,” which until recently had only been tested in the laboratory. Previous experiments by the Gonzalez group had shown that evolutionary rescue can prevent the extinction of an entire population when exposed to severe environmental contamination by a pesticide thanks to the rapid evolution.
However, the researchers note that the resistance to the herbicide came at a cost of plankton diversity. “We observed significant loss of biodiversity in communities contaminated with glyphosate. This could have a profound impact on the proper functioning of ecosystems and lower the chance that they can adapt to new pollutants or stressors. This is particularly concerning as many ecosystems are grappling with the increasing threat of pollution and climate change,” says Gonzalez.
The researchers point out that it is still unclear how rapid evolution contributes to herbicide resistance in these aquatic ecosystems. Scientist already know that some plants have acquired genetic resistance to glyphosate in crop fields that are sprayed heavily with the herbicide. Finding out more will require genetic analyses that are currently under way by the team.
Drifting algae in the Austral Ocean can bring invasive species to the Antarctic coasts, according to a new study. The report describes the first scientific evidence of a potentially invasive and colonial species –the marine bryozoan Membranipora membranacea- which reaches the Antarctic latitude islands in macroalgae that drift in the marine environment.
Solving the riddle of strigolactone biosynthesis in plants – The discovery of orobanchol synthase-
Strigolactones (SLs) are a class of chemical compounds found in plants that have received attention due to their roles as plant hormones and rhizosphere signaling molecules. They play an important role in regulating plant architecture, as well as promoting germination of root parasitic weeds that have great detrimental effects on plant growth and production.
This study was conducted as part of the SATREPS (Science and Technology Research Partnership for Sustainable Development) program by Dr. Wakabayashi, Prof. Sugimoto and their colleagues at the Graduate School of Agricultural Science, Kobe University, in collaboration with researchers from the University of Tokyo and Tokushima University. They discovered the orobanchol synthase responsible for converting the SL carlactonoic acid, which promotes symbiotic relationships with fungi, into the SL orobanchol, which causes root parasitic weeds to germinate.
By knocking out the orobanchol synthase gene using genome editing, they succeeded in artificially regulating SL production. This discovery will lead to greater understanding of the functions of each SL and enable the practical application of SLs in the improvement of plant production.
The results of this study were published in the International Scientific Journal Science Advances.
Strigolactones are known to have various functions such as the development of plant architecture, promoting mutually beneficial mycorrhizal relationships with fungi and serving as germination signals for root parasitic weeds.
Strigolactones are classified into canonical and non-canonical SLs based on their chemical structures. Canonical SLs have an ABC ring, whereas non-canonical SLs have an unclosed BC ring.
This study discovered the synthase gene responsible for converting the non-canonical SL carlactonoic acid into the canonical SL orobanchol.
The group succeeded in generating tomato plants with the synthase gene knocked out in which carlactonoic acid (CLA) accumulated and orobanchol production was prevented. The germination rate of root parasitic weeds was lower for these knock out plants.
Strigolactones (SL) are a class of chemical compounds that were initially characterized as germination stimulants for root parasitic weeds. SLs have also received attention for their other functions. They play an important role in controlling tiller bud outgrowth and also in promoting mycorrhizal symbiosis in many land plants, whereby plants and fungi mutually exchange nutrients.
Up until now, around 20 SLs have been isolated; with differences in stereochemistry in the C ring and modifications in the A and/or B rings. In recent years, SLs with unclosed BC rings have been discovered. Currently, SLs with a closed ABC ring are designated as canonical SLs, whereas SLs with an unclosed BC ring are non-canonical SLs. However, it is not clear which compounds function as hormones and which compounds function as rhizosphere signals.
If SL production could be suppressed, plants would induce the germination of fewer root parasitic weeds and their adverse effects on crop production would be mitigated. By increasing SL production, on the other hand, plant nutrition would be improved through the promotion of relationships with mycorrhizal fungi. Furthermore, manipulation of the endogenous levels of SL would control plant architecture above ground. Understanding the functions of individual SLs would lead to the development of technology to artificially control plant architecture and the rhizosphere environment. Consequently, there is much interest in how these SLs are biosynthesized.
It has been elucidated that SLs are biosynthesized from β-carotene. Four enzymes are involved in conversion of β-carotene to carlactonoic acid (CLA), a common intermediate of SL biosynthesis. In Japonica rice, conversion of CLA into orobanchol proceeds with two enzymes catalyzing two distinct steps. However, the biosynthesis pathway for orobanchol in other plants remained unknown. This study discovered the novel orobanchol synthase, which converts CLA into orobanchol in cowpea and tomato plants (Figure 1).
This research group had isolated orobanchol from cowpea root exudates and determined the structure. From metabolic experiments using cowpea, it was predicted that cytochrome P450 would be involved in the conversion of CLA into orobanchol. In this study, cowpea plants were grown in phosphate rich and poor conditions, where orobanchol production was restricted and promoted, respectively. The genes expressed in the roots of plants in both conditions were comprehensively compared. The group screened for CYP genes whose expression correlated with orobanchol production, expressed them as recombinant proteins, and performed an enzyme reaction assay.
From these results, it was understood that the VuCYP722C enzyme catalyzed the conversion of CLA to orobanchol. Furthermore, the SlCYP722C gene, a homolog of VuCYP722C in tomato was confirmed to be an orobanchol synthase gene. The SlCYP722C gene was knocked out (KO) in tomato plants using genome editing. In contrast to the wild type (control) tomato plants, orobanchol was not detected in root exudates of the KO plants, with CLA being detected instead.
Thus, the research group proved that SlCYP722C is the orobanchol synthase in tomato that converts the non-canonical SL CLA into the canonical SL orobanchol. The architecture of the KO and wild-type plants was comparable (Photo 1). This demonstrated that orobanchol doesn’t control plant architecture in tomato plants. It is thought that these KO tomato plants would still be able to benefit from mycorrhizal fungi, as the activity of CLA against the hyphal branching of the fungi was comparable with that of canonical SLs. Furthermore, it was found that the germination rate of the root parasitic weed Phelipanche aegyptiaca was significantly lower in the hydroponic media of the KO tomato plants (Figure 2). P. aegyptiaca causes great damage to tomato production all over the world, especially around the Mediterranean region. This research showed that it is possible to limit the damage that this parasitic weed does to tomato production by knocking out the orobanchol synthase gene.
This research group succeeded in preventing the synthesis of the major canonical SL orobanchol and accumulating the non-canonical SL carlactonoic acid. The same method can be utilized to elucidate the genes responsible for the biosynthesis of other canonical SLs. Further understanding of the functions of various SLs would allow plants to be manipulated in order to maximize their performance under adverse cultural conditions. Root parasitic weeds detrimentally affect not only tomato but a wide range of other crops including species of Solanaceae, Leguminoceae, Cucurbitaceae and Poaceae. These results will lead to the development of research to alleviate the damage inflicted by root parasitic weeds and increase food production worldwide.
Nearly everyone on Earth is familiar with corn. Literally.
Around the world, each person eats an average of 70 pounds of the grain each year, with even more grown for animal feed and biofuel. And as the global population continues to boom, increasing the amount of food grown on the same amount of land becomes increasingly important.
One potential solution is to develop crops that perform better in cold temperatures. Many people aren’t aware that corn is a tropical plant, which makes it extremely sensitive to cold weather. This trait is problematic in temperate climates where the growing season averages only 4 or 5 months – and where more than 60% of its 1.6 trillion pound annual production occurs.
A chilling-tolerant strain could broaden the latitudes in which the crop could be grown, as well as enable current farmers to increase productivity.
A group of researchers led by David Stern, president of the Boyce Thompson Institute, have taken a step closer to this goal by developing a new type of corn that recovers much more quickly after a cold snap. Stern is also an adjunct professor of plant biology in Cornell University’s College of Agriculture and Life Sciences.
“In the field, chilling stress happens most often in the spring when cold temperatures combine with strong sunlight, causing plants to bleach,” Stern said. “So a more chilling-tolerant corn could help farmers plant earlier in the year with confidence that their crop would survive a cold spell and bounce back quickly once the weather warmed up again.”
In the latest study, Stern and colleagues grew corn plants for three weeks at 25°C (77°F), lowered the temperature to 14°C (57°F) for two weeks, and then increased it back up to 25°C.
“The corn with more Rubisco performed better than regular corn before, during and after chilling,” said Coralie Salesse-Smith, the paper’s first author. “In essence, we were able to reduce the severity of chilling stress and allow for a more rapid recovery.” Salesse-Smith was a Cornell PhD candidate in Stern’s lab during the study, and she is now a postdoctoral researcher at the University of Illinois.
Indeed, compared to regular corn, the engineered corn had higher photosynthesis rates throughout the experiment, and recovered more quickly from the chilling stress with less damage to the molecules that perform the light-dependent reactions of photosynthesis.
The end result was a plant that grew taller and developed mature ears of corn more quickly following a cold spell.
Steve Reiners, a co-team leader for Cornell Cooperative Extension’s vegetable program, says that sweet corn is a major vegetable crop in New York, worth about $40-$60 million annually. He notes that many New York corn growers plant as soon as they can because an early crop commands the highest prices of the season.
“Many corn growers in New York plant early under protective plastic sheets to increase soil temperatures, which is expensive. Chilling-tolerant corn could allow farmers to remove that plastic sooner,” Reiners said. “This would expose the plants to additional sunlight, potentially enabling them to mature earlier in the season and get farmers those higher prices.”
Reiners, who was not involved in the study, is also a professor of horticulture at Cornell.
“The corn we developed isn’t yet completely optimized for chilling tolerance, so we are planning the next generation of modifications,” said Stern. “For example, it would be very interesting to add a chilling-tolerant version of a protein called PPDK into the corn and see if it performs even better.”
The researchers believe their approach could also be used in other crops that use the C4 photosynthetic pathway to fix carbon, such as sugar cane and sorghum.
Alternaria blight caused by fungal pathogen devastates Brassica crops such as cabbage, cauliflower, broccoli, and mustard seed. Highly infectious, this fungus can infect the host plant at all stages of growth. Currently Alternaria blight is managed by chemical fungicides, but recently efforts have been made to utilize breeding and modern biotechnological approaches to develop blight-resistant crop varieties.
Re-published with permission from John Innes Centre. Thank you to James Piercy for sharing.
‘Science is not finished until it is communicated’, so said Sir Mark Walport, former medical scientist and the Chief Executive of the UK Research and Innovation (UKRI). Unsurprisingly, being in the Communications and Engagement team, we agree with Sir Walport, and there are a number of ways that science can and is communicated. We can do:
use social media
organise outreach events
we have meetings
write reports and labour over publishing peer-reviewed papers.
Another vital method for peer-to-peer communication is at scientific conferences. Hordes of scientists from a particular field, come together to showcase their latest research and to learn about the work of their peers, collaborators or competitors.
Alongside the oral presentations, or talks, a key way to communicate the latest research and results is through ‘poster sessions’. Here scientists, of all levels in their careers, present their latest discovery on a sheet paper or fabric, pinned to a board.
Poster sessions provide an ideal
opportunity for peer-to-peer learning and should be an excellent
experience for presenter and viewer.
As a presenter, this is a
captive audience. There are large numbers of people who are interested
in your field of research and they are all there to learn. They want to
get their fill of new methods, exciting initial results and network with
like-minded people from all over the world.
But in reality, poster sessions aren’t as useful or enjoyable as they should be. Why is that?
There is a burgeoning grass roots initiative led by Psychology PhD student Mike Morrison, that believes that one of the reasons for this is that the posters on display at these sessions aren’t designed in the optimal way for the environment and context they’re used in. In other words, the audience posters are created for aren’t given the information contained within them, in a way that allows them to access it.
User-centred design is the process of considering how an object will, or needs to be, used and designing it accordingly. For example, think of a door which can only open in one direction. From one side the door needs to be pulled and from the other pushed. Effective user design of that door, would mean that on the pull side of the door there is a handle, allowing the user to pull open the door and on the other side, no handle but a flat plate.
A pull handle works perfectly on the
side of the door which needs to be pulled but hinders the user on the
push side. The handle implies that the user should pull the door,
potentially walking into it, before realising it doesn’t open in that
direction and then pushing the door.
Why? Because a handle suggests to the user that door needs to be pulled and thus influences the user’s behaviour. Wasted time and potential (minor) injury, all because of poor user design.
The same principles of considering how something will be used and then designing accordingly can be used for anything from doors to websites. It is here that Mike’s push to apply these principles to scientific posters comes in and his video (above) is well worth investing 20 minutes of your time.
When Mike, was first asked to make a scientific poster he thought the reason most academic posters look the way they do is because they have to. However, he soon learned that there were no rules for academic poster design enshrined into academic lore and realised there was a huge opportunity to improve the way research is communicated.
So, what can we do?
first thing is to change the way posters are designed and put together,
making them quicker and easier to create, which is great for the
We can also make them better at conveying the key
information, by considering what the purpose of the poster is; i.e. what
is it trying to tell people?
An ideal academic poster should accomplish three goals;
Maximise the amount of insight transferred to attendees of the poster session
Keep the good stuff; viewers still need detail and they need to encourage conversation
We need to achieve 1 and 2, in a way that is as easy and quick as making a poster within the current conventions, otherwise it won’t happen.
To do this, consider a completely blank page and think; “if I could only put one thing on here, what would it be?” The answer is probably, the main finding of the study, because what you found is the most interesting and most relevant thing you want to tell people.
you need a finding, or take-home message, to be placed prominently in
the front-and-centre, where it is easy to read and cannot be missed. The
next step is to take that finding, and without changing the meaning,
word it in such a way that it is both easy to understand and memorable.
For example, Mike found the following finding hidden away in the ‘Discussion’ section of one poster, which he then changed into Plain English;
“We found consistent differential validity for some
non-cognitive measures for predicting international student GPA,
specifically with SJT, Continuous Learning, Social Responsibility and
“For international students,
perseverance and a sense of social responsibility are extra important
for predicting first-year GPA”
Instantly making the key piece of information easier to digest and remember.
A good way to do this is to think of billboards which are designed to transmit information to people passing by them. As such, they provide a good starting point for scientific posters, which are essentially trying to do the same thing. Only our posters are ‘selling’ the research findings/methods/techniques, rather than a product.
while that is the key take home message, a good academic poster needs to
do more than just announce the headline, because behind every headline
is the story.
For that, Mike suggests a bar on the side of the poster on which you will normally stand, called an ‘ammo box’, which features all the data (tables, graphs etc) that back up the headline and which you would refer to, in order to answer any questions that arise from people who talk to you about your poster.
On the other side of the page, Mike suggests another bar, named ‘the silent presenter’ in which you add the sections that appear on almost all scientific posters, but slimmed down and formatted in a way to be easily consumed; i.e. in bullet points. It is in this bar that you would add; the question you started with, your collaborators, an introduction, the methods, results and discussions. This space can be used to provide people an overview of the study, assuming they will be reading it silently, in three or four minutes, rather than 10.
The side bars are a key part of the
proposed new template, because they allow you to include all the
information which appeared on the old design but arranged in a way that
is optimised according to how they are used.
With the design simplified, there is room to provide a source for the full study for people who are intrigued by your headline and would like to know more, but don’t have time to talk or read your ‘silent presenter’ bar.
a digital age, 99% of conference attendees will have a smart phone,
which can read QR codes. A QR code is easy to create and can be added to
a poster so that anyone can photograph it and find the full study, or
further information online, quickly, easily and without needing to
interact with you at all. Using QR codes allows you to include even more
information than a traditional poster allowed for, but in a format that
saves time, cognitive effort and in much less space.
All of this
taken together allows each person who sees your poster to take exactly
the level of information away from it they want, from just the headline
finding, through to digesting the full research paper.
Finally, another good tip we were given on our facebook account by Katia Hougaard is to include a stack of business cards with your poster, so that people could take your contact information with them and contact you later.
By following Mike’s advice, together we can design better scientific posters and improve the rate of scientific progress.
This is not to say that you have to use the layout Mike suggests, but we recommend trying to create a poster that teaches attendees something as they walk by, instead of relying on them to stop and talk to you, in order to learn about your work.
Dissolved carbon in soil can quench plants’ ability to communicate with soil microbes, allowing plants to fine-tune their relationships with symbionts. Experiments show how synthetic biology tools can help understand environmental controls on agricultural productivity.
As social beliefs and values change over time, scientists have struggled with effectively communicating the facts of their research with the public. Now, a team of researchers believe scientists can gain trust with their audience by showing their human side. The researchers say it can be as simple as using “I” and first-person narratives to help establish a personal connection with the audience.
Plant breeders are always striving to develop new varieties that satisfy growers, producers and consumers. To do this, breeders use genetic markers to bring desirable traits from wild species into their cultivated cousins. Transferring those markers across species has been difficult at best, but a team of grapevine breeders, geneticists and bioinformatic specialists has come up with a powerful new method.