Wednesday, July 4, 2018

170 years after the famine, the late blight of potatoes remains

Dundee, Scotland, 1861
Despite the tools available to combat and control plant disease, the pathogen which caused the Irish famine continues to destroy potato crops worldwide

The famine wasn’t that long ago. I can trace my family back to Peter Lettice and his wife Mary Lowrie who left Ireland in the early 1840s, in their case for Dundee, Scotland, to avoid starvation. Many people can do the same. Knowing their names means that the headline figures that get used in connection with the famine - one million dead and one million emigrated - become very personal. Those figures get used whenever anybody talks about the famine, but they make the whole thing anonymous in a way. It's something that happened to other people and their families.

The massive global changes brought about by the famine are still evident in the large number of people claiming Irish heritage in North America, Australia and elsewhere. At home, the population of the island of Ireland (approximately 6.5 million in 2016) has only now returned to pre-famine levels.
Historians can rightly point to many contributing factors and causes for the famine. Political, social and economic issues all played a role, but the cause of the crop losses at the heart of the Irish potato famine ultimately was Phytophthora infestans. This pathogen comes from a group of organisms called oomycetes and can no longer be correctly called a fungus. In fact, it’s more closely related to the brown algae.

The ‘father’ of plant pathology, Anton de Bary, was the first to demonstrate experimentally that the pathogen caused the disease we now know as late blight and de Bary coined the name Phytophthora, meaning "plant-destroyer". English botanist Rev. Miles Berkeley had first observed that late blight was "the consequence of the presence of the mould, and not the mould of the decay" 15 years earlier (Journal of the Horticultural Society of London, 1846).

Phytophthora is an appropriate moniker. Symptoms of the disease include blackish lesions on the leaves and purple-brown lesions on the surface of the tubers themselves. When the disease is advanced, the tubers are rotten inside and there is a distinctive odour which must have struck fear into the heart of poor subsistence farmers all over the country during the famine.

As any potato grower will tell you, late blight of potatoes has not gone away. It remains the most economically destructive of all potato diseases worldwide. Typically, commercial potato growers in Ireland use between 15 and 20 applications of fungicide to control the pathogen every year and there are no commercially-viable resistant varieties available. 170 years after the famine, our potato crop is still as vulnerable as ever to destruction caused by Phytophthora. The difference now is the availability of chemical control options to keep the worst of the losses at bay.

Globally, many crops are vulnerable to diseases that have the potential to cause devastating losses. For example, rice blast fungus (Magnaporthe oryzae) is the most destructive disease of rice, a staple foodstuff that feeds half the world’s population. Diseases of cereals like Puccinia and Fusarium are a threat that require constant vigilance and we are regularly reminded that the much-loved and economically important Cavendish variety of banana (that’s the banana you had for lunch) is on the brink of extinction due to Panama disease caused by Fusarium oxysporum.

A major problem is our over-reliance on a small number of crops for much of the world’s food supply. Just 15 crop plants account for 90 percent of the world’s food with maize, wheat and rice accounting for over 50 percent of the world’s caloric intake (UN FAO). If even one of the top ten crops were to fail, the consequences could be catastrophic, especially for developing countries.
Increasingly though, we are running to stand still with a lot of the major diseases. Much like the Red Queen in Lewis Carroll’s Through the Looking-Glass, keeping one step ahead of emerging and evolving plant pathogens "takes all the running you can do, to keep in the same place".

In this context, it’s more important than ever that we are using all of the tools available to us to combat and control plant disease. That means an integrated approach to pathogen and pest management where one tool such as chemical control is not over-used. Such reliance on one control method runs the risk of forcing the pathogen to evolve to overcome the control measure, rendering it useless.

One of the tools that will certainly be in that toolbox is the development of resistant varieties. However, in the case of late blight, we’ve yet to breed a commercially-viable, fully blight-resistant potato. That’s not to say it’s impossible: Sarpo Mira, Sarpo Axona and Blue Danube are all potato varieties that are very resistant to late blight but they have not been commercially successful outside of the organic market.

Luckily, help is at hand in the form of modern plant biotechnology which has the capacity to quickly develop blight resistant potato varieties as well as resistant crops to various other diseases) A major problem with conventional potato breeding is the difficulty in crossing domesticated varieties with their disease-resistant wild relatives. Genetic transformation has overcome that problem by transferring a potato gene for resistance from wild to cultivated varieties. Such varieties were grown successfully in Ireland in recent years.

Gene-editing technology will allow even more precise changes to be made to plant genomes with the goal of introducing resistance for a host of important crop diseases. Whatever our personal views on such technologies, there is no doubt they will be an integral part of maintaining global food security and preventing future famines.

Recently, Ireland was named the most food-secure nation in the world. That’s an amazing turnaround, even if it has taken 170 years. In light of our remarkably journey from famine to world leaders in food security, surely there is a moral imperative on us to support other countries to boost their food security - and to advance the science that will prevent similar famines from happening to other countries in the years to come?

The National Famine Commemoration 2018 takes place at University College Cork on Saturday May 12th. The International Association for Plant Biotechnology congress 2018 (IAPB2018) takes place in Dublin in August

This article first appeared on RTE Brainstorm.

Time for a new debate about food production

Producing enough food to feed a growing human population while protecting an environment under pressure will mean changes in lifestyle, diet and food production.

The Citizens’ Assembly recently voted in favour of introducing measures to reduce the impact of food production on the environment. 89 percent of the assembly members voted to recommend a tax on greenhouse gas emissions from agriculture with the revenue raised being invested in climate-friendly agriculture. This begs the question: what exactly is "climate-friendly agriculture"?

An overwhelming majority of 93 percent of assembly members also recommended the government take action to curb food waste throughout the food production and supply chain. This is a much needed intervention. Although major retailers have made moves to reduce food waste significantly, one study has estimated that 50 percent of all food produced globally never reaches a human mouth. Instead, it is lost on the farm, in processing, storage, distribution or in the back of fridges.

This is a staggering waste given that the secure access to food is a basic human right. Article 25 of the Universal Declaration of Human Rights declares it is "the right of every man, woman and child…to have physical and economic access at all times to adequate food". It’s a noble aspiration but it’s clear that we are struggling to make that a reality on a global scale. Figures just realised by the Food and Agriculture Organisation of the United Nations tells us that 815 million people remain undernourished. A sobering figure.

It’s no surprise then that how we produce enough food to feed a growing human population (approximately eleven billion by 2100) while protecting an environment under pressure has never been higher on the agenda. Unfortunately, we can’t get away from the organic versus conventional debate when we discuss food production these days and evidence suggests that it is the wrong debate to be having

Research indicates that organic systems require anywhere between 25 and 110 percent more land than comparable conventional systems and cause more eutrophication of water bodies than conventional farming. When it comes to crop yields, it really depends on the type of crop you’re growing but, on average, organic yields are 25 percent below that of crops grown conventionally. There are other advantages of organic production though, such as increased soil quality and overall farm biodiversity.
But this is a debate that is going round in circles. There are advantages and disadvantages to both systems and we’ll need to use the best parts of all farming systems if we’re going to solve the global food security crisis.

We need to have a different discussion. It’s now well established that plant-based foods have the lowest environmental impacts and that meat production (especially cattle and sheep) has around 100 times the environmental impact of plant-based food. We need to discuss a dietary shift from beef to pork or from meat to plant-based food. That’s the debate we should be having. Going organic has some environmental benefits, but that’s negligible compared to the benefits of a dietary shift.

 Former president Mary Robinson suggested last year that adopting a vegan diet would reduce our carbon footprint (cue wailing and gnashing of teeth from farmers organisations). Pope Francis recently suggested a similar "change in lifestyle" when speaking at a World Food Day event.

We’ve also got to consider the potential role of genetically engineered crops and crops that have had their genome edited using such techniques as CRISPR. The technology is now available to make photosynthesis more efficient. As the driving force for life on earth, improving photosynthesis could be the key to improving crop yields in a sustainable manner.

CRISPR, a technology that that has far-reaching consequences beyond plant biotechnology, allows scientists to precisely engineer even single letter changes in a plant’s genetic code. This can be done without the need for transgenic DNA, making it radically different to the now conventional forms of genetic engineering which, though leading to huge advances in crop production worldwide, remain a controversial topic in Ireland and most of Europe as this recent Irish survey shows.

These tools join conventional and organic methods in a farmers tool-box. It seems unreasonable that with such challenges to overcome, we often opt to do so with one hand tied behind our back. We now need a new green revolution for the 21st century.

In 1708, the English cleric and economist Thomas Malthus wrote that the "premature death" of the human race was inevitable given the power of population increase over the ability to provide food for these new people. Despite his scaremongering, we’ve obviously overcome these challenges and seen dramatic increases in food production and human population over the last two centuries.

Much of the yield increase has been due to the adoption of (at the time) novel tools for plant breeding and cultivation – the so-called ‘green revolution’. We now need a new green revolution for the 21st century. A green revolution that is not limited by ideology but uses all proven and safe technologies available to boost yields while protecting the environment.

This article first appeared on RTE Brainstorm

Wednesday, June 22, 2016

Eating Japanese Knotweed (and other daft ideas)

Image: Wikipedia
There have been a number of calls(1,2,3,4) in recent weeks and months to control the invasive plant Japanese Knotweed, at least partially, by eating it. In recent days, Kerry County Council in Ireland heard from one member who, albeit with tongue-in-cheek, urged citizens to make wine, jelly and other sweet treats from the plant.

This strikes me as a terrible idea.

The plant itself is certainly edible - the Japanese have been eating it for years. It's Japanese name, itadori, means 'well being' and it seems to have some medicinal properties. It also tastes a bit like rhubarb apparently. I wouldn't know, I haven't tried it.

I haven't tried it for the same reason I don't advise you try it. Encouraging people to harvest and transport a regulated, invasive species is the perfect recipe (if you'll pardon the pun) for its continued and accelerated spread.

Japanese Knotweed (Fallopia japonica) is, as you will have guessed, native to Japan and the neighbouring region. It was introduced to the UK in the mid-19th century and quickly spread to Ireland and other parts of the world. Introduced as an ornamental plant, it quickly became a real problem.

The plant is capable of growing at a tremendous rate - 1 metre in a month- and forms big stands 2-3 metres in height. The early shoots are spear like, similar to asparagus in appearance and the plants produce delicate white flowers in late Summer. The real problem is underground where the plant forms tough rhizomes, adapted root-like organs, which remain in the soil even during the Winter when the rest of the plant dies back.

Japanese Knotweed thrives on disturbance and it is mainly spread by fragments of rhizome, crown or stem being accidentally or deliberately moved. This leads to some real (and expensive) problems including a massive reduction in biodiversity under the alien canopy; structural damage to buildings and infrastructure; and the significant cost of its removal.

Data from 2010 suggest that the plant costs the UK £165 million a year to control. If the plant were to be eradicated in the UK by current methods it would cost £1.56 billion. For one site alone, the 2012 London Olympic site, it cost £88 million to deal with this one invasive plant. Nobody wants Japanese Knotweed on their land.

Image: Wikipedia
Imagine you go to the supermarket and buy a bunch of rhubarb. The first thing you do is chop the top and bottom off the stalks and chuck them on your compost heap. Do this with Japanese Knotweed and you end up costing yourself (and potentially your neighbours) thousands in a cleanup bill.

Harvesting Japanese Knotweed from the wild, no matter how careful you are, is also fraught with problems. The plant can easily regrow from small fragments the size of your fingernail. If we're lucky, you'll drop these fragments at the original, infested site. If not, you'll drop them on your walk back to the car or in your front garden when you unload the car.

Simply put, encouraging people to mess around with an invasive species like Japanese Knotweed is, in my view, irresponsible. It may also be illegal.

In Ireland, it is an offence to "plant, disperse or cause to disperse or otherwise cause to grow" the plant. It is also an offence if "he/she has in his/her possession for sale or for breeding/reproduction/transport....anything from which the plant can be reproduced or propagated".

In the meantime, there are chemical and physical control options and scientists in the UK are developing a biological control approach using a sap-sucking insect called Aphalara itadori. This is an old enemy of the plant, found in Japan and currently being tested in the UK to see if it will do the same job in this part of the world (and not eat anything else, by accident). The trials haven't been a total success with numbers surviving over winter too low to have much of an effect, but the tests are ongoing. Hopefully, before too long we will have a sustainable control option for this invasive plant. In the meantime, stop eating it.

Friday, April 8, 2016

Dealing with Food Waste

Recent reports that Irish people are wasting one million tonnes of food give us, as the old idiom goes, food for thought.

According to some reports, this translates into 2 billion meals and around€1 billion worth of food. At a time when some of our citizens struggle to put food on their table, this is a worrying statistic. The figures also represent bad news for our environment and indicate a food production system under pressure.

Ireland is not alone in our wastage of food. A 2013 UK study suggested that, worldwide, between 30 and 50% of all food produced never reaches a human mouth. That amounts to about 1.3 billion tonnes of food wasted every year on the planet, with losses in developing countries mostly down to inefficient growing and harvesting. In developed countries, like Ireland, consumer waste is a huge issue. Put in monetary terms, $1 trillion worth of food is wasted every year, according to the UN Food and Agriculture Organisation.

Up to 30% of the UK and Ireland’s vegetable crops are never harvested due to changing, and some might argue, unreasonable demands from the big supermarkets. This is very slowly changing. Under pressure from consumers and activists, some supermarkets have introduced ranges of fruit and vegetables which are perfectly edible but aren’t the perfect shape or size that is normally demanded. These “ugly” or “wonky” fruit and vegetables are a step in the right direction but represent just a drop in the ocean compared to the amount of produce that is destroyed each year because it doesn’t meet retail guidelines. 

So, think about that loaf of bread that you forgot about in the back of the cupboard and had to put in the bin after a few weeks. The first thing you should reflect on is that you really should clean your cupboards out more often. After that, it’s worth remembering that it’s not only the loaf of bread you’re putting in the bin. You’re also wasting all of the energy, water and other resources which went in to producing that loaf. 

From start to finish, from field to bakery to supermarket shelf, a 1kg loaf of bread takes about 1,600 litres of water to produce. Agriculture is thirsty work.

If you choose to add some roast beef to your bread it gets even worse: 1kg of beef takes 15,000 litres of water to produce. And that’s just one resource. You’ve also got to factor in the land, energy, fertilisers and pesticides it took to produce these foodstuffs that are ending up in the bin. Food waste is unsustainable.

About 9 billion people will live on this planet in 2050. According to the United Nations, we have enough food already to feed that many people if it was more fairly and less-wastefully distributed. With advances in agricultural technology, plant breeding and plant protection products, we are getting better at producing higher yields on the same amount of land. 

Energy is another limiting factor for food production, especially in light of obligations to curb climate change. For every calorie of plant-based food, it costs around 3 calories worth of energy to produce. However for every calorie of beef produced it costs 35 calories. When most of this energy comes from non-renewable resources like fossil fuels, meat (and dairy) consumption starts to look unsustainable on a global scale.

At the recent COP21 meeting in Paris, it was estimated that around a quarter of all greenhouse gas emissions globally come from agriculture. So, agriculture is a cause of global climate change but it is also a victim of it. Changes in weather patterns, temperature and rainfall will increasingly dictate what kinds of crops will be grown where. Agriculture will be forced to change if it doesn’t do so voluntarily. This is an opportunity for Ireland to lead global change to a more sustainable model of food production.

In fairness, the issue of food waste is being taken seriously at the highest level. One of the results of the COP21 talks has been the establishment by the G20 group of countries of a Technical Platform to measure and reduce food loss and waste. Recently, the Rockefeller Foundation has pledged $130 million to help sub-Saharan African farmers to improve their harvesting, storage and food transportation systems.

More locally, organisations like FoodCloud and the Bia Food initiative are finding innovative ways to connect companies with food at risk of becoming waste with charities who can use such food to fight hunger. Meanwhile, in Denmark a charity has just opened a supermarket stocking exclusively ‘surplus’ food. There is no doubt that for business, the issue of food waste has become an image problem and an opportunity to engage with society to develop novel solutions.

If all of that doesn’t convince you to waste less food, it’s worth pointing out that the Environmental Protection Agency reckons the average Irish household throws away about €700 worth of food every year. We bin 50% of all the salad we buy. 25% of all fruit and vegetable that we buy are thrown away (with potatoes and bananas being main culprits). 20% of bread and 10% of meat and fish is also dumped in homes up and down the country.

A small amount of food waste in unavoidable and food safety is an important issue. However, we all have an obligation to drastically reduce the levels of food waste if we are to develop a fairer, more sustainable society.

Dr Eoin Lettice is a plant scientist and lecturer at the School of Biological, Earth and Environmental Sciences at University College Cork. This article originally appeared in the Evening Echo.

Friday, April 17, 2015

George Boole Road?

I had a thought....surely a bad idea to begin with, but regardless....

As we celebrate the year of George Boole and the wonderful, imaginative and informative celebratory events are in full swing, I got to thinking that there is no street named after the man in Cork.

This is George Boole, the noted academic, scientist, mathematician, teacher and father of the information age who spent much of his working life in Cork City and who died and was buried here.

UCC has done phenomenal work keeping his name alive, going back to the building of the Boole Library in 1983. However, at a civic level, his name has been somewhat neglected, not withstanding the plans by Cork City Council and UCC to refurbish his former home at Grenville Place.

So, I'm suggesting that Boole is probably about due a street named after him in Cork. Now, street naming is not a completely uncontroversial topic and there may be people who disagree with me, especially if we go usurping some other street and swapping some other historical figure's name with that of the noted mathematician. To avoid (some) of this controversy, perhaps Western Road in Cork City should be renamed in his honour?

Here we have a road which is geographically appropriate, as it is the formal address of UCC. It also is named for nothing more that the direction of traffic.

It's just a suggestion. Don't bite my head off. But let the debate start here.

Comments welcome.

Food for thought

With the world population set to reach 9 billion people by 2050, it’s no surprise that governments and societies are beginning to rethink how they will produce food for all these extra people. 

In Ireland, we’re lucky to have some of the most ideal conditions to produce lots of healthy, nutritious food; with a benevolent climate, committed producers and a world-class ‘food infrastructure’ built up over time. 

In Cork – ‘Ireland’s food capital’. Someone who wanders around the cathedral to food that is the English Market cannot fail to notice the importance of food to this region and the central place it has within our city. With a proposed new food innovation centre on the Grand Parade, it looks like that moniker of Ireland’s food capital is being assured.

Ireland’s exports of food and drink reached nearly €10.5 billion in 2014, with the industry making up about 9% of total employment in the country. The Irish food industry has been one of the success stories of the Irish economy throughout the last number of very difficult years. The challenge, as we seek to grow this sector and produce more food for a growing world population, will be to do so in ways that are sustainable and do as little damage to the environment as possible.

English Market, Cork. (Image: William Murphy, Creative Commons)

There are many ways in which this sustainability can be achieved. For example, both industry and consumers have a real obligation to ensure that food waste is minimised as much as possible. Some estimates put the total percentage of food wasted and lost before it gets in our stomachs at between 30 and 50% globally. That means that up to half the food in our fields never reaches a human mouth and is lost either under attack from pests and diseases in the field or binned by suppliers, supermarkets or consumers for a variety of reasons. 

How we grow food crops is the subject of much debate. And so it should be. Consumers have an obligation to be informed about the way in which their food is produced. Hence the recent debates around issues like pesticide residues, genetically-modified crops, organic production, etc. These are good conversations to be having. If nothing more, a country like Ireland which relies on the food industry for 9% of its total employment must be informed about the best food production and plant protection techniques.

At University College Cork, we have a long history of studying plants and crop production. We are also the second ‘greenest’ university on the planet and the first third-level institution in the world to fly the green flag for environmental policies. So, the production of food crops in an environmentally sustainable way is a central tenet of our teaching and research at the School of Biological, Earth and Environmental Sciences at UCC. 

In 2012 we launched Europe’s only MSc course in organichorticulture to service a growing demand for higher qualifications in the sector. Organic horticulture (and organic production in general) is often defined by what it isn’t rather than what it is. For example, most synthetic chemical fungicides and pesticides are not permitted for use by organically certified growers so they must employ alternative plant protection techniques like biological control. 

From a scientific point of view, that poses some really interesting research questions like how we can increase yields of plants in ways which don’t rely on synthetic chemical inputs. For example, conventional potato growers often apply between 15 and 20 applications of fungicide each season to control late blight of potato (that’s the same disease which caused the Irish famine). That works for now, but there are clear drawbacks to this approach, putting all your eggs (or potatoes) in one basket. Research on ‘organic’ control techniques for late blight means that we might be able to expand our options for controlling this important disease in one of our most important crops. This sort of research can have benefits for both organic and conventional agriculture.

Organic horticulture is not without its challenges. The lack of conventional chemical fertilisers and pest control means organic yields are often lower than that obtained through conventional means. Additionally, and despite a premium paid for organic produce, small organic growers can often find it hard to balance the books. By recognising the main challenges, we can focus our research strengths accordingly so that we improve the lot of organic growers as well as farmers in general. This will ensure that the organic produce that consumers want is on the shelves and, where possible, is produced in Ireland.

At the moment, the organic sector in Ireland accounts for just less than 1.2% of our useable agricultural area (PDF). The retail value of the sector is about €100 million annually. The current government aims to increase this area under organic production considerably. For example, the Food Harvest 2020 plan seeks to have 5% of our useable agricultural area under organic cultivation by 2020. To do this, significant training of new organic growers is required along with upskilling of current growers. Additionally, there is a need for significant research and development in the area of organic crop production in Ireland. The MSc Organic Horticulture programme at UCC has the dual aims of training scientists and producing a body of Irish research on organic crop production techniques.

From looking at alternative methods of controlling slugs with coffee grounds and seaweed, to using computer software to monitor disease outbreaks in potato, to the study of charcoal as a soil additive, we’ve already produced a range of research through this MSc programme. This is the sort of research which is needed to ensure that growers have a variety of tools at their disposal to produce the food we want, when we want it.

This article first appeared in the Evening Echo on April 14th 2015.

Dr Eoin Lettice is a plant scientist and lecturer at the School of Biological, Earth and Environmental Sciences at University College Cork.

Thursday, March 12, 2015

Homeopathy doesn't work

As if it needs restating, there is no evidence that homeopathy works.

This fact has been reconfirmed by a recent report by the Australian National Health and Medical Research Council.

Having reviewed the scientific evidence they found that:

  • There was no reliable evidence from human research that homeopathy was effective for treating a range of health conditions.
  • For some conditions, the placebo was more effective than homeopathy.
  • People who choose homeopathy may put their health at risk if they reject or delay treatments for which there is good evidence for safety and effectiveness.

You can read the full report here.

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