The role that potatoes can play in improving the lives and health of the world’s population was a major theme of the tenth World Potato Congress held at the origin of the crop in Cusco, Peru. The event was held alongside the Latin American Potato Association congress and opened by Peru’s President Martin Vizcarra.
The congress was a very technical one, with nearly all presentations given by academics. While that did allow delegates to learn about the latest potato science, it meant they did not hear from many growers or commercial processing, packing and input suppliers who have the job of converting science into practical business solutions.
One speaker that did bridge the disciplines of science and business was Dr Maximo Torero, executive director of the World Bank. He highlighted the mis-match between a 40% increase in global potato production since 1990 and a doubling in the volume and a 400% increase in the value of potato trade in that time. He said that most of that increase in trade has been in frozen product, such as fries, which can be globally shipped. However, that means that much of the increase in the global value of potato production has been confined to developed countries, with just four countries – Belgium, Netherlands, Canada and USA accounting for more than 80% of frozen fry exports. Just 6% of world potato production is globally trade, compared to 17% for grains.
Torero said that the economic clout that developed countries have has enabled them to build efficient and competitive processing plants and absorb tariffs or restrictions on trade. The World Trade Organisation tariff on frozen fry exports is nearly 15%. EU processors have the advantage that 70% of the 5 million tonnes of product they export is sold to other EU countries, which is tariff-free, allowing them to establish the scale of production that makes them very competitive in other markets too. More than 85% of Canada’s exports are to the US and free of duties, while the US also has tariff-free agreements with many markets that it sells to.
Torero argued that if more countries are to benefit from the global demand for potato products there needs to be more attention from governments in helping to develop industries and greater efforts in reducing tariff barriers and ensuring that phytosanitary standards and technical regulations are only used to ensure the safety of potatoes being traded rather than as a means of restricting trade.
All the world’s largest potato trading nations have the ability to produce potatoes for processing at yields above 40 tonnes/hectare. That rate provides the volume of competitively priced potatoes a plant needs. World Potato Markets calculations show that a plant with a production of 200 000 tonnes of fries a year needs 400 000 tonnes of potatoes to supply it, which is 10 000 hectares of land growing potatoes every year yielding 40t/ha.
If potatoes are in rotation once every four years, then the minimum amount of land needed to support a modern processing plant is 40 000 hectares, while in many parts of the world rotations are longer at one in five years growing potatoes.
There are pockets of land across the world producing more than 40 tonnes/hectare supplying processing plants, including in China, Russia, Argentina and New Zealand, but the volumes involved are much smaller than those in the EU and North America.
Improving yield is a focus for many of the potato geneticists who gathered at the World Potato Congress, but they expressed the desire not to forfeit yield for quality. Argentine seed breeder Marcelo Huarte said that potatoes have a significant role in improving the low quality diets experienced by three billion people living across every country in the world. But improvements will have to come against a backdrop of continued population growth, climate change and urbanisation. He said that the potato industry will need to deploy improved breeding, including disease resistance, stress tolerance and genetic enhancement; precision agriculture (targeted use of inputs and enhanced agronomy); the use of biological products to improve soil quality; improved irrigation; more targeted agrochemicals and better financial support from governments and the private sector.
Research highlights at the World Potato Congress
The dozens of presentations at the congress proved that the potato is one of the world’s most diverse crops, with perhaps as much or more undiscovered as known potential. Governments and businesses across the globe view the crop as a way of feeding people nutritionally and affordably. From using resources more efficiently to resisting pest, drought and disease to breeding enhanced health benefits and even the appeal of peel, here’s a roundup of the research presented at the congress, using the headings used at the event.
Climate Change & the Potato
A project involving the USDA, International Potato Centre (CIP) Peruvian agricultural centre INIA and Asociacion ANDES has used the application of inexpensive calcium supplements to increase yield in 30% of the 1 200 native cultivars it tested, with gains from 10% to 100%. Elsewhere, genetic exploration of native species means that new frost-tolerant varieties are being released to local growers.
A joint- South African and Dutch project found that higher levels of atmospheric carbon dioxide as a result of climate change can enhance photosynthesis and reduce water use. However, higher temperatures associated with climate change put more stress on potatoes, so growers will need to avoid production during particularly hot periods. Meanwhile, a CIP project in sub-Saharan Africa has seen the release of three varieties in Kenya that do not experience a drop in yield in environments that experience 20%-30% less rain and have temperatures that are 2C to 3C higher than in more benign potato growing conditions. Joint CIP and German institute work has shown that Andean potato growers will be increasingly threatened by potato tuber moth as the climate changes.
Trends in Potato Consumption
Matching grower and consumer demands in potatoes was the subject of a Dutch/Ecuadorian project in Ecuador. A survey of 500 growers, traders and consumers discussed preferences. Perhaps unsurprisingly, growers focused on agronomic traits, consumers on tuber quality and processing traits and traders on marketability. Overall, the ideal potato should be resistant to late blight, high yielding and early maturing, but those traits should not sacrifice taste, yellow flesh and the versatility that allows single potato varieties to be suitable for several uses. The information is being used to develop new varieties in the country.
CIP projects released 491 improved varieties into the South and East Asian markets between 1951 and 2014, with 210 of these varieties in use in 2014 (43%), which is 30% of the overall total. Of the 7.6 million hectares of potato land in the region, 97% of the area planted between 2014 and 2016 was to improved varieties, mainly due to strong Indian and Chinese programmes. However, 20% of land in Nepal and Bangladesh is still planted with unimproved landraces. Of the 7.6 million ha of potatoes in the region, 1.4m ha is planted with CIP varieties. One particularly successful CIP variety developed with Yunnan Normal University In China is Cooperation-88. Research estimates that the late-blight resistant variety introduced in 2001 has resulted in up to US$3 billion extra income for growers and still accounts for 17% of production in the Yunnan region.
Brazilian research of 100 consumers looking at the acceptance of coloured potatoes with higher levels of antioxidants found that only 2% of consumers were prepared to pay no premium for coloured types, while 65% would pay between 25% to 50% more than standard types, 19% twice as much, 11% three times as much and 3% four times as much. Whether those intentions were translated into reality is unknown.
Potato Variety Development & Biotechnology
Colombian researchers have mapped the genetics of the two most important agronomic problems for potatoes in the country – late-blight and Guatemalan potato tuber moth. The knowledge is allowing them to develop resistant varieties. A joint Spanish and Ecuadorian project has genetically sequenced 200 potato accessions highlighting their ability to resist stresses such as drought and heat.
Disease robs up to 40% of potential potato yield, according to a presentation of a CIP/UK/Poland research project. Recent genetic improvements has seen the controlling of late-blight by using wild potato relatives in commercial varieties, with virus resistance to Potato Virus Y (PVY) now achieved along with resistance to bacterial wilt. A major gene resistant to Potato Leaf Roll Virus (PLRV) will be isolated soon, with resistance to nematodes now being assessed too. The researchers said that a research and development environment that funds genetic improvement and policies that support the use of genetic technology could result in a 30% increase in potato productivity that would increase grower profitability and improve environmental protection across the world.
CIP is leading a project to improve iron and zinc levels in potatoes by introducing genes from less genetically complex diploid varieties into more complex tetraploid commercial types. More than 13 000 genotypes have been whittled down to 360, with iron levels of between 24mg/kg to 45mg/kg and zinc at 15-35mg/kg. From that list of 360, 50 have been prioritised for variety selection in Latin America, Africa and Asia. To put the figures in context, white potatoes normally have iron levels of between 5-8mg/kg and zinc 3.5mg/kg.
New breeding techniques such as genetic marking, genotyping and phenotyping is speeding up and reducing the cost of the process of variety development, according to Irish researchers. Genetic marking allows traits to be stacked together and breeding cycles to be shortened. The focus of government-supported work in the country has been on fry colour and improved storage traits. Future work will look at environmental adaptation of potatoes.
Japanese research has genetically removed toxic steroidal glycoalkaloids (SGAs) from potatoes, which develop in sprouts and green tubers and can cause food poisoning. The research not only removed the SGAs, but led to the accumulation of steroidal saponins, which enable the synthesis of pharmaceutical drugs such as anti-inflammatory, androgenic, estrogenic and contraceptive drugs.
Using seeds, rather than tubers, Dutch company Solynta is developing diploid potatoes with similar yields to commercial tetraploid controls. That is speeding up the development of new varieties.
Potato Pest & Diseases
US company Maronne Bio Innovations has isolated beneficial bacteria to combat a range of diseases including blight, rhizoctonia and root knot and pests such as lesion nematodes and wireworms. Similar work in Belgium has seen the significant control of late blight, with researchers confident that antagonistic indigenous soil bacteria will be an important alternative to the use of fungicides and pesticides, some of which are losing their efficacy. Dutch work shows that popular blight spray Fluazinam, introduced in 1992, is less effective than it was in the past. Meanwhile, Canadian work shows that the use of spore traps allowed growers to detect the threat of blight up to 15 days earlier than normal, allowing them to protect crops with fungicides earlier.
The stacking of genes (particularly Rpi and Ry) should mean that there will eventually be a potato variety that can combine blight, PVY, bacterial wilt nematode resistance, according to British scientists. Meanwhile Chinese researchers said there is still room for chemical control of blight and presented work on the use of Phosphite fungicides showing a 2 hour uptake into leaves and significantly increased uptake of chemical after 24 hours, protecting the crop more strongly and for longer than alternatives. Phosphite can also be used as a post-harvest treatment to prolong storage periods.
Peru might be the home of the potato, but that means it is also probably the home of the potato virus too. An investigation by CIP researchers found much greater numbers and intensity of viruses than expected in the native potato growing regions and are now using that knowledge to develop systems to better understand and combat those viruses in the country and further afield.
Bacterial wilt (pictured) is a major problem in Sub-Saharan Africa. A CIP project in the region found the disease in between 50% to 70% of Ugandan, Kenyan and Ethiopian potato farms causing yield losses of between 30% to 100%. Infected seed and soil mean that the disease is endemic on many farms, but applications of neem kernel cake and organic fertiliser Plantmate, along with the use of high quality selected seed, which can be multiplied on-farm, reduces latent infection by 70% to 90% and saw some yields increase from a tiny 2 tonne/ha to as much as 40t/ha.
Just like humans, aphids have their favourite potato varieties too, research in Argentina has discovered. Using this knowledge, breeders can identify genes in varieties aphids reject to use in commercial types and keep the pests at bay.
Potato Crop Management
Better understanding of evapotranspiration replacement (water losses from irrigation) is helping preserve or increase yields with reduced water use, scientists from Colorado State University in the US told the congress. In one case tuber bulking was faster and yields maintained despite a 17% reduction in irrigation water. Another finding was a 20% reduction in nitrogen fertiliser when pinto beans were added to the rotation. Work in Florida, US, found that a combination of sub-surface drip irrigation, sub-irrigation drainage tiles and a sprinkler system reduced water use and increased nitrogen fertiliser efficiency.
Research in Sicily by Italian research institute IVALSA found that coinciding irrigation with growth phases of the potato crop can save water without reducing yield. Only watering from tuber initiation to 50% of tuber growth rather than throughout the whole crop cycle resulted in high tuber yields and good tuber quality with a 870m³/ha reduction in water use.
The Belgian potato industry has worked with Government institute VITO to develop a satellite system that monitors temperature and rainfall to develop a predictive risk monitoring system for the potato crop. Launched last year, 300 growers, responsible for 10% of the national crop, registered for the free-to-use WatchITgrow system. The data is also available to Belgian traders and processing companies, allowing them to better plan their season.
Argentine researchers have used intercepted radiation (solar energy captured on the plant), total biomass and tuber yield to assess yield development in four french fry processing varieties. The length of the crop cycle (measured by intercepted radiation) was the most important factor determining total biomass and yield. This was then followed by radiation use efficiency (how well plants use radiated energy) and then harvest index (the measurement of crop yield).
A Brazilian project used five soil treatments to improve microbial activity, including the addition of grasses and maize into rotations. The most successful intervention was the use of deep tillage and the introduction of the grass Panicum maximum into the rotation.
Post-harvest & Processing technology
Work by the World Bank and US and Belgian researchers found that food loss in seven value chains (including potatoes) between producers and processors in six developing countries was between 6% and 25% of total production. Of those losses up to 80% were with the primary producer, around 7% with traders or middlemen and 19% with processors. Other studies have found that in developed countries losses can be as much as a third, with those losses concentrated at the consumer part of the chain.
Storing potatoes at 12C and 90% relative humidity were the best conditions for preserving desirable nutritional polyphenol and antioxidant qualities of coloured native and commercial white potatoes, according to joint Chilean and Uruguayan research. The 12C level beat potatoes stored at 4C and 20C. The research also found that polyphenol levels were two to three times higher in coloured native potatoes than white ones. Research suggests that polyphenols offer some degree of protect against cancer and heart disease. Swiss and Belgian research has studied data collected over 25 years from 721 cultivars in order to better understand dormancy to optimise the value of potatoes and reduce the application of anti-sprouting products. Researchers concluded that 80% of the variability in dormancy is down to a combination of cultivar type and temperature between emergence and harvest. This knowledge means growers can predict when sprouting may take place, allowing them to target treatments.
Potato Biodiversity for breeding, nutrition & health
CIP and US researchers shared work on the genetic cataloguing of the CIP gene bank. They found 12 000 single nucleotide polymorphism (SNP) genetic markers in the 140 species of potatoes they hold – there are 157 known species. Genotypes for 9 292 of these 12 000 SNPs were found containing 1 417 tetraploid cultivars. The work in identifying the world’s largest potato genetic resource should help the development of enhanced yield and nutritional varieties. A joint CIP and Canadian project is seeking to improve the genomic knowledge of as many types of potatoes as possible, giving researchers from across the world access to its data.
The world’s potato processors might be removing the best bit of the potato when they remove 70 000 tonnes of peel a year, said researchers from the processing heartland of the USA, Idaho. They said that micro molecules of copper, and nickel along with pectin, polyphenols and calystegine in the peel regulate digestive glycaemic enzyme response improving blood glucose levels and moderating the body’s desire for more food. Fortunately for the State’s processors old-time favourite variety Russet Burbank’s peel had the highest level of inhibitors of 12 types tested.
Although there was enough science to make the head of the non-scientist ache, there was one presentation that was more about culture than just agriculture. American artist Jeffrey Allen Price (pictured left from Europatat’s Twitter feed) has turned his love of potatoes into a philosophy called Potatoism leading to the collection of more than 6 000 potato-related artefacts, art exhibitions featuring the potato, the creation of a film called This is how I say Potato and a potato-themed podcast.
More details can be found here www.jeffreyallenprice.com or at Allen price’s Instagram feed www.instagram.com/explore/tags/potatoism/
The 2018 World Potato Congress’s website is www.worldpotatocongress2018-alap.org/en/home/
Andean research centre unlocks its treasures
A highlight of the congress was a trip to the Andenes Experimental Station nearly 4 000 metres above sea level an hour’s drive from Cusco. It is run by Peru’s National Institute for Agricultural Innovation (INEA) and uses terraces that have been growing potatoes for more than 1 000 years. The cultural importance of the potato was clear on the visit, with the crop bound-up with traditional pre-Inka and Inka beliefs as well as providing a staple food for generations.
But the research centre is looking to the future, while respecting the past by developing and understanding its gene bank of nearly 6 000 varieties and investigating affordable technologies to allow Andean growers to produce higher quality and yielding varieties.
Visitors to the station were able to see what is believed to be the earliest potato species Moreliformia Haw, the basis of potato production almost 10 000 years ago and one of 140 species held at the location. There was also a demonstration of the tools used to pant and harvest potatoes for many of those 10 000 years (pictured right). The exhaustion of the soil at the site has led to a collaboration between researchers and global organic soil improvement company Bioflora.
One project at the station that could have significant health benefits is looking at the role that anthocyanin in purple-fleshed potatoes could have in reducing colonic cancer, with encouraging result for two of the varieties held at the site, Amachi and Leona. Also on display was the work that CIP is doing to improve zinc and iron levels in potatoes.
<image027.png>Much of the work at the research station has a practical benefit across the world and the facility is taking a lead at developing aeroponic, aquaponic and sandponic seed tuber systems that will allow growers to develop vigorous breeding stock in all conditions.
Closer to home, a simple project giving Andean growers access to high-quality seed was demonstrated. Poor quality home-saved seed that is diseased and genetically depleted is a problem for many growers, so a co-project between the Peruvian Ministry of Agriculture, the local district Government and a hydro-electric company is providing 50% funding for a US$350 screenhouse, which allows groups of growers to grow 10 000 high quality seed plants sheltered from the threat of pests and frost and improve the quality and yield of their crop (pictured above). Meanwhile, in an environment where mobile phone signals are good, but mobile internet connections are not and smartphones are expensive, CIP and INEA have developed a card-based system that warns growers of the the threat of blight and protect their crops based on weather conditions.
Although the focus was inevitably on potatoes at the centre, other crops were highlighted too including lupins in rotations, while Olluco and Yacon are tubers that are grown throughout South America and getting a following further afield.
Next stop Ireland
The World Potato Congress takes place every three years and the next host is Ireland, a country where the potato is fundamental to its history and culture both positively and negatively. It will be held in Dublin in May 2021. Organisers have promised a mix of potato science, policy and business that will appeal to all parts of the potato chain and include plenty of opportunities to see production in action and celebrate the potato with Ireland’s famous hospitality.
The congress is a non-profit organisation with the mission of creating a global network to encourage the sustainable development of the potato and increase global uses and demand for the crop. Its President is Belgian Romain Cools and he says that the congress wishes to increase its impact between main world events, which has resulted in an African workshop in 2017 and the launching of potato value chain tool box in Peru that includes advice and case studies on six areas of potato development.
1. Collaboration between local individuals or groups with partners who want to develop their Corporate Social Responsibility.
2. Provision of quality planting material.
3. Farm management and crop production technologies.
4. Sustainable production and storage of potatoes.
6. Creating added value through packaging and processing.
Source : World Potato Markets / Cedric Porter