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Sustainability & Environment

The emerald ash borer (Agrilus planipennis) is a metallic green beetle from Asia that is wiping out trees across the eastern US. First detected in Michigan in 2002, the pest is spreading rapidly and has killed billions of ash trees, with seven out of nine ash trees in North America threatened by this newcomer.

tree in eastern US

This is only the latest in a litany of exotics to ravage American forests. Sixty-two high-impact insect species and a dozen pathogens have arrived since the 1600′s. Only two were detected before 1860.

 The emerald ash borer

The emerald ash borer. Image; Wikimedia Commons

Increased global trade and travel, along with climate change and warmer winters, are all fueling the problem. And the devastation has pushed scientists and foresters to look towards biotechnology for a remedy.

‘Almost every day there appears to be a new forest pest and some of these are quite devastating,’ says tree geneticist Jeanne Romero-Severson at the University of Notre Dame, Indiana, US. 

‘Biotech approaches such as transgenic technology and CRISPR gene editing could be valuable tools in saving specific species.’

 forest

These biotech solutions look sexier to funders, and policymakers, and that is where the resources go. But in many ways, it is a dead end if you don’t have a foundational breeding programme to feed into,’ warns DiFazio, a plant geneticist at West Virginia University, US.

A technology like CRISPR for gene editing is fast and powerful, but mostly it is used in lab organisms where much is known about their genetics. Without deep knowledge of a tree’s genome, CRISPR will be far less useful.

 CRISPR

CRISPR is a gene editing tool that first came to prominence in the 1990′s and is considered one of the most disruptive technologies in modern medicine.

Powell, a plant scientist at the State University of New York (SUNY), US acknowledges that ‘the biggest thing is to the get the public onboard; a lot of people are afraid of genetic engineering. 

Surveys suggest that knowledge about genetic engineering technology, as well as about threats to forest health, is fairly low amongst the general public. Given these deficits, ‘public opinion might be vulnerable to changes,’ notes Delborne.


Sustainability & Environment

Scientists studying DNA in soil samples from Svalbard in the High Arctic have discovered a surprisingly large number of clinically-important antibiotic resistance genes. In total, 131 antimicrobial resistance genes were identified, while five out of eight sites had abundant multidrug resistance genes.

 The Svalbard Islands

The Svalbard Islands are in Northern Norway.

The finding is all the more unexpected as the team was seeking a virgin environment to try and establish what a background level of antimicrobial resistance in soil bacteria looks like. 

 soil bacteria

Scientists found genes important to antimicrobial resistance in soil bacteria.

‘We took 40 samples to give us an idea of what the baseline of resistance might look like in nature, but we were surprised by how different the sites were from each other,’ says lead scientist David Graham at Newcastle University. Areas with high wildlife or human impact had greatest diversity of resistance DNA in the soil.

The results show that antibiotic resistance genes are accumulating even in the most remote locations. Included in a number of samples was a multidrug resistant gene called New Dehli strain, first isolated in India.

Newcastle University find antibiotic resistant genes in Arctic. Video: Newcastle University

Some sites had levels of antimicrobial resistance 10 times greater than others, particularly those with elevated levels of phosphorus, a nutrient usually scarce in Arctic soils. 

‘There was much greater resistance diversity in sites with strong signatures of faecal matter,’ says Graham, indicating that migratory birds most likely brought the antimicrobial resistance genes, depositing them via their guano.


Health & Wellbeing

The first perfumes designed by AI are slated for launch in mid-2019 in Brazil. Developed at IBM, in partnership with perfume company Symrise, the AI programme used drew upon a database of 1.7m different fragrance formulas, and used information on raw materials and the success of previously developed perfumes. It was also taught to identify which fragrances people found similar and dissimilar – getting training akin to an apprentice perfumer.

perfume

Called Philyra, after the Greek goddess of fragrance, the AI programme developed two new fragrances for Brazilian beauty company O Boticário. 

‘What she did was super innovative. She had a sweet warm background, but added cardamom-like Indian cuisine scents and a milk that came from the flavour department,’ says David Apel, Senior Perfumer with Symrise. ‘From 1.7m formulas, it is amazing for her to find something that hadn’t been done before.’

Using AI to create new fragrances. Video: IBM Research

In a demonstration at IBM Research in Zurich, Switzerland, computational researcher Richard Goodwin demonstrated how Philyra is able to scan 1,000 different formulations, and over 60 raw materials, and compare them with fragrances currently on the marketplace. It is possible to request a certain type of perfume and adjust its novelty.


Health & Wellbeing

Roughly 60% of the 12 million animal experiments in Europe each year involve mice. But despite their undoubted usefulness, mice haven’t been much help in getting successful drugs into patients with brain conditions such as autism, schizophrenia or Alzheimer’s disease. So too have researchers grown 2D human brain cells in a dish. However, human brain tissue comprises many cell types in complex 3D arrangements, necessary for true cell identity and function to emerge.

Researchers are hopeful that lab grown mini-brains – tiny 3D tissues resembling the early human brain – may offer a more promising approach. ‘We first published on them in 2013, but the number of brain organoid papers has since skyrocketed, with 300 just last year,’ says Madeline Lancaster at the Medical Research Council’s Laboratory of Molecular Biology lab in Cambridge, UK.

 pippette and petri dish

Lancaster was the first to grow mini-brains – or brain organoids – as a postdoc in the lab of Juergen Knoblich at the Institute of Molecular Biotechnology in Vienna, Austria. The miniature brains comprised parts of the cortex, hippocampus and even retinas, resembling a jumbled-up brain of a human foetus.

‘We were stunned by how similar the events in the organoids were to what happens in a human embryo,’ says Knoblich. To be clear, the brain tissue is not a downsized replicate. Lancaster compares the blobs of tissue to an aircraft disassembled and put back together, with the engine, cockpit and wings in the wrong place.

Growing mini brains to discover what makes us human | Madeline Lancaster. Video: TEDx Talks  

‘The plane wouldn’t fly, but you can study each of those components and learn about them. This is the same with brain organoids. They develop features similar to the human brain,’ she explains.


Sustainability & Environment

The European Court of Justice (ECJ) ruled in July 2018 that onerous EU regulations for GMOs should also be applied to gene edited crops. The ECJ noted that older technologies to generate mutants, such as chemicals or radiation, were exempt from the 2001 GMO directive, but all other mutated crops should be regarded as GMOs. Since gene editing does not involve foreign DNA, most plant scientists had expected it to escape GMO regulations.

‘We didn’t expect the ruling to be so black and white and prescriptive,’ says Johnathan Napier, a crop scientist at Rothamsted Research. ‘If you introduce a mutant plant using chemical mutagenesis, you will likely introduce thousands if not millions of mutations. That is not a GMO. But if you introduce one mutation by gene editing, then that is a GMO.’

What is genetic modification? Video: The Royal Society

The ECJ ruling will have strong reverberations in academe and industry. The European Seed Association described the ruling as a watershed moment. ‘It is now likely that much of the potential benefits of these innovative methods will be lost for Europe – with significant economic and environmental consequences,’ said secretary general Garlich von Essen.

In 2012, BASF moved its plant research operations to North Carolina, US, because of European regulations. ‘If I was a company developing gene editing technologies, I’d think of moving out of Europe,’ says Napier.

 crop field 3

‘The EU is shooting itself in the foot. Its ag economy has been declining since 2005 and it has moved from net self-sufficiency to requiring imports of major staples,’ says Maurice Moloney, CEO of the Global Institute for Food Security in Saskatchewan, Canada. ‘Paradoxically, it still imports massive quantities of GM soya beans and other crops to feed livestock.’

 

Health & Wellbeing

Traditional electronics are made from rigid and brittle materials. However, a new ‘self-healing’ electronic material allows a soft robot to recover its circuits after it is punctured, torn or even slashed with a razor blade.

Made from liquid metal droplets suspended in a flexible silicone elastomer, it is softer than skin and can stretch about twice its length before springing back to its original size.

Soft Robotics & Biologically Inspired Robotics at Carnegie Mellon University. Video: Mouser Electronics 

‘The material around the damaged area automatically creates new conductive pathways, which bypass the damage and restore connectivity in the circuit,’ explains first author Carmel Majidi at Carnegie Mellon University in Pittsburgh, Pennsylvania. The rubbery material could be used for wearable computing, electronic textiles, soft field robots or inflatable extra-terrestrial housing.

‘There is a sweet spot for the size of the droplets,’ says Majidi. ‘We had to get the size not so small that they never rupture and form electronic connections, but not so big they would rupture even under light pressure.’

Health & Wellbeing

A shortage of donor organs for transplant surgery is fueling research to develop artificial livers and hearts, but how closely do they match up to the real thing?

Liver failure due to alcohol abuse, drug overdose and hepatitis is a growing problem. In 2016, 1220 Americans died waiting for a liver transplant, with the cost of treating cirrhosis – late stage liver scarring – is estimated at nearly $10bn/year.

‘In 2017, if you have liver failure, we don’t have a backup system,’ says Fontes. ‘But my group has a potential backup system. We are not ready for prime time yet, but we’ve some really good data.’

 bar and alcohol

Liver failure can be hereditary or caused by excessive drinking. Image: Pixabay

Transplant surgeon Paulo Fontes at the University of Pittsburgh, US, regularly meets patients who ask what their options are aside from a liver transplant.

His group has attempted to build a new bioartificial liver, by seeding liver cells onto a liver scaffold. However, others working in this area have so far met with little success.

Now Fontes, working at the Starzl Transplantation Institute, has hit on a different strategy: to grow mini livers in living organisms. The work is in collaboration with Eric Lagasse, a stem cell biologist at the University of Pittsburgh, who showed lymph nodes are excellent ‘bioreactors’ for growing different types of cells, including liver cells.

 The liver made up of hepatocytes

The liver – made up of hepatocytes – has the capacity to regenerate after surgery. Image: Ed Uthman/Flickr

Lymph nodes filter damaged cells and foreign particles out of the body’s lymph system, which transports fluids around the body. When someone is ill, T cells from the immune system move to the lymph nodes to be cloned and released back to the bloodstream en masse to take on the microbe causing the illness.

For the past five years, Fontes and Legasse have been working with large animal models, infusing hepatocytes into the lymph nodes of pigs. ‘Within two months, it is amazing, but you have mini livers in the lymph nodes,’ he explains. ‘When you compare the mini liver with normal livers, they look very similar.’

 a pig

Pigs are common animal models as they have similar organ systems to humans. Image: Pixabay

The mini livers weigh a few grams and would not offer a complete replacement for failed livers, but rather a supplement of liver tissue in patients with end stage liver disease who are too sick to undergo a transplant.

‘A lot of these patients have significant heart and lung problems, so would not sustain a full transplant,’ says Fontes. ‘The idea is to sustain their life by increasing their liver mass by creating new small ectopic livers within their lymph nodes.’

Compared with artificial livers, artificial heart technology is much further along the road to the clinic. To date, around 2000 artificial hearts have been implanted in patients, with demand driven similarly by an acute shortage of donors.  

heart gif

Originally posted by electric-hearts-war

‘We wanted an artificial heart very similar to the natural human heart,’ explains Nicolas Cohrs at ETH Zurich in Switzerland. ‘Our hypothesis is that when you mimic the human heart in function and form you will have fewer side effects.’

Cohrs and his colleagues aim to print their artificial hearts so that they fit precisely into an individual patient. This is not yet close to clinic, but promises a tailored heart.

‘We take a CT scan of a patient, put it in a computer file and design an artificial heart around it, so it closely resembles the patient heart,’ says Cohrs. ‘We use these 3D printers and print a mould in ABS [acrylonitrile butadiene styrene], which is the plastic Lego is made of, fill it with silicone and then dissolve the mould with acetone to leave behind the silicone heart.’

Testing a soft artificial heart. Video: ETH Zurich

The plastic heart deflates and inflates with pressurised air. The first-generation device, made from silicone, has two chambers but survived for only 2000 beats. ‘This is only half an hour, so there is a lot of improvement needed,’ adds Cohrs.

A new prototype made from a more resistant [so far, undisclosed] polymer has managed more than a million beats, which is the equivalent of 10 days for a human heart. The goal is to develop a four-chamber heart that beats for 10 years, so a lot more work is still needed.


Health & Wellbeing

A new type of wheat, chock full of healthy fibre, has been launched by an international team of plant geneticists. The first crop of this super wheat was recently harvested on farms in Idaho, Oregon, and Washington state in the US, ready for testing by various food companies.

Food products are expected to hit the US market in 2019. They will be marketed for their high content of ‘resistant starch’, known to improve digestive health, be protective against the genetic damage that precedes bowel cancer, and help protect against Type 2 diabetes. 

How do carbohydrates impact your health? Video: TED-Ed

‘The wheat plant and the grain look like any other wheat. The main difference is the grain composition: the GM Arista wheat contains more than ten times the level of resistant starch and three to four times the level of total dietary fibre, so it is much better for your health, compared with regular wheat,’ says Ahmed Regina, plant scientist at Australian science agency CSIRO.  

Starch is made up of two types of polymers of glucose – amylopectin and amylose. Amylopectin, the main starch type in cereals, is easily digested because it has a highly branched chemical structure, whereas amylose has a mainly linear structure and is more resistant. 

 Bread2

Bread and potatoes are foods also high in starch. Image: Pixabay

Breeders drastically reduced easily digested amylopectin starch by downregulating the activity of two enzymes, so increasing the amount of amylose in the grain from 20 to 30% to an impressive 85%.  

The non-GM breeding approach works because the building blocks for both amylopectin and amylose starch synthesis are the same. With the enzymes involved in making amylopectin not working, more blocks are then available for amylose synthesis.  

cloud gif

Originally posted by flyngdream

‘Resistant starch is starch that is not digested and reaches the large intestines where it can be fermented by bacteria. Usually amylose is what is resistant to digestion,’ comments Mike Keenan, food and nutrition scientist at Louisiana State University, US. ‘Most people consume far too little fibre, so consuming products higher in resistant starch would be beneficial.’

He notes that fermentation of starch in the gut causes the production of short-chain fatty acids such as butyrate that ‘have effects throughout the body, even the mental health of humans’.  

 GM wheat

The GM wheat will hit US supermarkets in 2019. Image: Pxhere

The super-fibre wheat stems from a collaboration begun in 2006 between French firm Limagrain Céréales Ingrédients, Australian science agency CSIRO, and the Grains Research and Development Corporation, an Australian government agency.

This resulted in a spin out company, Arista Cereal Technologies. After the US, Arista reports that the next markets will be in Australia and Japan.

Energy

 Tesla

Tesla is at the forefront of industrial battery technology research. 

Electric cars are accelerating commercially. General Motors has already sold 12,000 models of its Chevrolet Bolt and Daimler announced in September 2017 that it is to invest $1bn to produce electric cars in the US, with Investment bank ING, meanwhile, predicts that European cars will go fully electric by 2035.

‘Batteries are a global industry worth tens of billions of dollars, but over the next 10 to 20 years it will probably grow to many hundreds of billions per year,’ says Gregory Offer, battery researcher at Imperial College London. ‘There is an opportunity now to invest in an industry, so that when it grows exponentially you can capture value and create economic growth.’

The big opportunity for technology disruption lies in extending battery lifetime, says Offer, whose team at Imperial takes market-ready or prototype battery devices into their lab to model the physics and chemistry going on inside, and then figures out how to improve them.

Lithium batteries, the battery technology of choice, are built from layers, each connected to a current connector and theoretically generating equivalent power, which flows out through the terminals. However, improvements in design of packs can lead to better performance and slower degradation.

 Lithium batteries

Lithium batteries need to be adapted for electric vehicle use. Image: Public Domain Pictures

For many electric vehicles, cooling plates are placed on each side of the battery cell, but the middle layers get hotter and fatigue faster. Offer’s group cooled the cell terminals instead, because they are connected to every layer. ‘You want the battery operating warmish, not too hot and not too cold,’ he says.

‘Keeping the temperature like that, we could get more energy out and extend the lifetime three-fold.’ If the expensive Li ion batteries in electric cars can outlive the car, he says their resale value will go up and dramatically alter the economic calculation when purchasing the car. ‘If we can get costs down, we will see more electric vehicles, and reduced emissions and improved air quality,’ Offer says.


Alternatives to lithium ion

Battery systems management and thermal regulation will allow current lithium batteries to be continually improved, but there are fundamental limits to this technology. ‘Lithium ion has a good ten years of improvements ahead,’ Offer predicts. ‘At that point we will hit a plateau and we are going to need technologies like lithium (Li) sulfur.’

 

Will Batteries Power The World? | The Limits Of Lithium-ion. Video:  minutephysics

Li sulfur has a theoretical energy density five times higher than Li ion. In September 2017, US space agency NASA said it will work with Oxis Energy in Oxford, UK, to evaluate its Li sulfur cells for applications where weight is crucial, such as drones, high-altitude aircraft and planetary missions.

However, Li sulfur is not the only challenger to Li ion. Toyota is working to develop solid-state batteries, which use solids like ceramics as the electrolyte. ‘They are based around a class of material that can conduct ions at room temperature as a solid,’ Offer explains. ‘The advantage is that you can then use metallic lithium as the anode. This means there is less parasitic mass, increasing energy density.’


Futuristic chemistries

 BMWs electric cars

The carbon-fiber structure and Li ion battery motor of one of BMW’s electric cars. Image: Mario Roberto Duran Ortiz

For electric cars, the ultimate technology in terms of energy density is rechargeable metal-air batteries. These work by oxidising metals such as lithium, zinc or aluminium with oxygen from the air. ‘Making a rechargeable air breathing electrode is really hard,’ warns Offer. ‘To get the metal to give up the oxygen over and over again, it’s difficult.’ 

Development in the area looks promising, with the UK nurturing battery-focused SMEs and forward-thinking research groups in universities. The latest investment plan envisages support that links across research, innovation and scale-up, as championed by Mark Walport, the government’s Chief Scientific Advisor.

The Faraday Challenge – part of the Industrial Strategy Challenge Fund. Video: Innovate UK  

Introducing a programme to directly tackle this challenge ‘would drive improved efficiency of translation of UK science excellence into desirable economic outcomes; would leverage significant industrial investment in the form of a “deal” with industry; and would send a strong investment signal globally,’ says Walport.

Health & Wellbeing

Around 10 million medical devices are implanted each year into patients, while one-third of patients suffer some complication as a result. Now, researchers in Switzerland have developed a way to protect implants by dressing them in a surgical membrane of cellulose hydrogel to make them more biocompatible with patients’ own tissues and body fluids.  

‘It is more than 60 years since the first medical implant was implanted in humans and no matter how hard we have tried to imitate nature, the body recognises the implant as foreign and tends to initiate a foreign body reaction, which tries to isolate and kill the implant,’ says Simone Bottan at, who leads ETH Zurich spin-off company Hylomorph.

 Hylomorph

Hylomorph is a spin-off company of ETH Zurich, Switzerland. Image: ETH-Bibliothek@Wikimedia Commons

Up to one-fifth of all implanted patients require corrective intervention or implant replacement due toan immune response that wraps the implant in connective tissue (fibrosis), which is also linked with infections and can cause patients pain. Revision surgeries are costly and require lengthy recovery times.

The new membrane is made by growing bacteria in a bioreactor on micro-engineered silicone surfaces, pitted with a hexagonal arrangement of microwells. When imprinted onto the membrane, the microwells impede the formation of layers of fibroblasts and other cells involved in fibrosis.

 pacemaker

25,000 people in the UK have a pacemaker fitted each year. Image: Science Photo Library

The researchers ‘tuned’ the bacteria, Acetobacter xylinum, to produce ca 800 micron-thick membranes of cellulose nanofibrils that surgeons can wrap snuggly around implants. The cellulose membranes led to an 80% reduction of fibrotic tissue thickness in a pig model after six weeks, according to a study currently in press. Results after three and 12 months should be released in January 2018.

It is hoped the technology will receive its first product market authorisation by 2020. First-in-man trials will focus on pacemakers and defibrillators and will be followed by breast reconstruction implants. The strategy will be to coat the implant with a soft cellulose hydrogel, consisting of 98% water and 2% cellulose fibres.  

The membrane will improve the biocompatibility of implants. Video: Wyss Zurich

‘Fibrosis of implantables is a major medical problem,’ notes biomolecular engineer Joshua Doloff at Massachusetts Institute of Technology, adding that many coating technologies are under development.

‘[The claim] that no revision surgery due to fibrosis will be needed is quite a strong claim to make,’ says Doloff, who would also like to see data on the coating’s robustness and longevity.

The silicone topography is designed using standard microfabrication techniques used in the electronics industry, assisted by IBM Research Labs.  

Health & Wellbeing

Large-scale industrial mining of asbestos began towards the end of the 19th Century; predominantly in Russia, China, Kazakhstan, and Brazil. 

This relatively cheap material with excellent fire and heat resistance, good electrical insulating properties, and high-tensile strength was used widely in the construction industry and in many other products, including brake pads, hair dryers, and industrial filters for wine, beer and pharmaceuticals. Worldwide, an estimated two million tons of asbestos is used annually.


Health risks

But asbestos exposure can be deadly. Anyone who handles the material or breathes in its fibres puts themselves at risk of lung diseases, such as asbestosis or cancer. The World Health Organization estimates that in a single year over 100,000 deaths are due to asbestos-related diseases.

 Lung asbestos

Lung asbestos bodies after chemical digestion of lung tissue. Image: Wikimedia Commons

‘The truth is that it is a nasty, hazardous, toxic, carcinogenic material that has made millions and millions of people sick,’ says Arthur Frank, Professor of Environmental and Occupational Health at Drexel University, Philadelphia, US. Frank is a longtime advocate for banning the mineral.

To date, around 60 countries have banned the use of asbestos, including the UK. Russia, India, and China, however, still use asbestos in a range of products. The US is the last among developed countries not to ban asbestos entirely. More significant for Western countries are the millions of tonnes of asbestos left in buildings – asbestos becomes a problem if disturbed, especially if the fibres go undetected.

 construction workers

Asbestos is a health risk to construction workers. Image: Pixabay

Traditionally, those who work in the building trade are most at risk, though workers can bring home fibres on their clothes, which poses a risk to anyone they come into contact with.

‘There is a significant amount of data that points to as little as one day of exposure being sufficient to give rise to malignancy in humans and animals,’ says Frank. It’s unclear precisely the cellular mechanism, he says, but health experts agree that asbestos poses a severe public health risk. In the UK, asbestos is responsible for half of work-related cancer deaths.

 The European Parliament

The European Parliament was one of the first to ban all future asbestos use. Image: European Parliament@Flickr

The European Parliament has pushed for the removal of asbestos from all public buildings by 2028. The asbestos industry, however, argues that it is wrong to say that any exposure to asbestos can kill and believes there is a permissible level of exposure.


Rising litigation

In the US, asbestos-related litigation is increasingly common. ‘The companies put up a fight in most cases, delaying settlement until practically the eve of trial and disputing everything they can as to medical diagnosis and causation, and evidence of the plaintiffs’ exposure histories,’ says Barry Castleman, an environmental consultant who has spent 40 years working on asbestos as a public health problem.

However, man-made substitutes for asbestos-based construction materials are available. For over 50 years, asbestos was combined with cement in Europe because its fibres are mechanically strong and durable, says Eshmaeil Ganjian, Professor of Civil Engineering Materials at Coventry University, UK.

 PVA

PVA is also widely used in glue. Image: Pixabay

These boards were used for internal and external walls as well as for roofs. Europe now uses polyvinyl alcohol – widely known as PVA - in its cement boards, Ganjian says, but this is more expensive than asbestos, which has come down in price over the past 20 years.  


Waste not, want not

Ganjian is currently working on a project aimed at replacing asbestos in cement boards in Iran with waste plant fibres, such as Kraft pulp, and polymeric fibres such as acrylic and polypropylene fibres. ‘The idea is to use locally available fibres, so we use cheap acrylic fibres available from petrochemical companies in the region. The strength of cellulose fibres is lower than asbestos fibres, but when we add polypropylene or acrylic or other synthetic fibres then this increases the mechanical strength,’ he explains.

 Shiraz Iran

Shiraz, Iran. Image: Wikimedia Commons

The Iranian government subsequently stopped importing asbestos from Russia and banned its use in cement board factories, switching to local alternatives. ‘This was a win-win situation. It saves lives and uses a waste material,’ says Ganjian.  

Sustainability & Environment

On average, 10% of all crop production is lost annually to drought and extreme heat, with the situation getting worse year on year. Heat stress happens over short-time periods, but drought happens over longer timescales and is linked to drier soils. Maize and wheat are especially hard hit, with yields falling by up to 50% if drought hits.

On the High Plains, the largest US wheat-growing region, drought is a possibility every season. ‘Drought stress can be a key concern, especially in dry lands, but even in irrigated areas we can’t expect the same levels of water in future and farmers face restrictions,’ says Chris Souder at Monsanto.  

So, this is not simply a developing world problem. Pedram Rowhani, University of Sussex, UK, found cereals in more technically developed agricultural systems of North America, Europe, and Australia suffered most from droughts. Yield losses due to drought were 19.9% in the US compared to almost no effect in Latin America.

Crop breeders in the past paid a great deal of attention to yield, but not enough to resilience to extreme events such as drought, Rowhani says, but this is changing. Growers increasingly want built-in drought resilience and plant scientists are looking for novel solutions. New, unconventional approaches based on novel insights from basic science might be necessary.


Plant strategies

Hundreds of genes and proteins are involved in the complex trait of drought resistance. Plants avoid drought stress by shortening their life cycle with accelerated flowering, or cut down water loss by closing leaf pores called stomata. One approach by breeders is to target specific traits by crossing individual plants that perform best under drought conditions.

 Stomata

Stomata are found of the underside of leaves and are used for gas exchange. Image: Pixabay

‘About 97% of plant water loss occurs through the stomata. If you want to regulate the amount of water a plant uses, regulate the stomata,’ says Julie Gray, University of Sheffield, UK. Gray has been genetically tweaking wheat, barley, and rice plants so they have fewer of these pores.

She believes rising CO2 levels in the atmosphere means that they do not suffer from less carbon dioxide from opening their stomata. ‘CO2 levels have gone up 40% over the last 200 years. It’s quite possible they are producing more stomata than they need,’ says Gray.

 Power plant in Tihange

Power plant in Tihange, Belgium. CO2emissions continue to increase. Image: Hullie@Wikimedia Commons   

Gray reports that plants grown at 450ppm CO2 with reduced stomatal density, but increased stomatal size, had larger biomass and increased growth tolerance when water was limited. ‘Plants can operate with perhaps half as many stomata before you see significant effects on photosynthesis, so you can definitely reduce water loss this way,’ says Gray.


Root of the issue

At the other end of the plant plumbing system are roots. Susannah Tringe, Joint Genome Institute, UK, is seeking microbes that can gift stress-tolerance to their plant hosts. ‘The microbes associated with plants are likely to be just as important for plant growth and health as the microbiome of humans,’ says Tringe.

Though a lot of work has focused on finding the ‘magic microbe,’ Tringe believes whole communities will be necessary in real field conditions, whereas a single strain could be out-muscled by competitors. 

Regular bouts of drought are leading to famine in developing countries. Video: Food and Agriculture Organization of the United Nations 

Sugar and drought

‘Drought is probably the most widespread abiotic stress that limits food production worldwide. There is always need to improve drought tolerance,’ says Matthew Paul, Rothamsted Research Institute, UK.

‘Sucrose is produced in photosynthesis,’ Paul explains. ‘During drought conditions, plants will withhold sucrose from the grain, as a survival mechanism’. This can terminate reproductive structures and abort seed formation, even if drought is short-lived, greatly compromising yield.

 A plant scientist studying rice plants

A plant scientist studying rice plants. Image: IRRI Photos@Flickr

Rothamsted researchers have looked at modifying plants so sugar keeps flowing. ‘If you can get more sugar going to where you want it […] then this could improve yields and yield resilience,’ enthuses Paul. Field studies show that GM maize improved yields from 31 to 123% under severe drought, when compared with non-transgenic maize plants.