Potato breeding

Last changed: 15 May 2017
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A hot potato

Larger field trials, increased funding for long-term potato breeding, and a coordination of the breeding activities in Sweden, Norway and Finland – that’s what we need to get a sustainable potato cultivation in the north.

Talking about potato, Sweden, Norway and Finland have a lot in common. We prefer the floury potato cultivars, while elsewhere in Europe people prefer the firmer potatoes. We have the cold northern climate in common, with long days in the short summer, and problems with the same kind of pathogens. On the other hand we have no major problems with drought. Therefore, drought tolerance is not a particularly prioritized potato trait in this region.

With this in mind, researchers at SLU suggest that the three countries join hands and cooperate to develop new better potato cultivars.

In a scientific paper, researcher Dennis Eriksson and his colleagues presented an overview of the potato cultivation, consumption and potato processing in Fennoscandia (Sweden, Norway and Finland). The development of new potato varieties have diminished in Norway and Sweden, and ceased altogether in Finland.

– This is a shame because potato is the highest yielding food crop here. At the same time, potato is an irreplaceable part of our food culture, and the potato breeding has a long and proud history in our countries, says Dennis Eriksson.

Having previously decreased for decades, potato consumption has remained steady at just above 40 kg per person and year in Sweden the last 20 years. Do we want to continue to eat potatoes in the future? Can we grow potatoes more sustainable than today? Yes, scientists believe so, but sustainability requires smart strategies.

We need potato varieties that do not need to be sprayed with fungicides. All the varieties we grow today are susceptible to late blight caused by the pathogen Phytophthora infestans. The spraying is bad for the environment and makes potato cultivation more expensive. Potato varieties also need to eventually be adapted to a future climate, predicted to become warmer and wetter in the north. And more pests are expected to find their way to this region as the climate changes.

– A high and stable potato production, under the particular conditions that we have in the north, is crucial. This requires an early tuber maturity due to the short summer season. And, in addition to late blight, there are other potato diseases that are common in this region, says Dennis Eriksson.

The researchers say that the Fennoscandian market is too small to motivate the profit-driven breeding companies to invest in potato breeding that matches the specific requirements of this region. Consequently we rely on public investment to develop new varieties, and such financial support must be maintained for a long time.

In their study, the researchers present seven reasons for public investment in potato breeding in the Fennoscandian region:

  1. National food self-sufficiency is an issue of high priority.
  2. The environmental quality objectives A non-toxic environment and A varied agricultural landscape,adopted by the Swedish Parliament, will greatly benefit from new potato cultivars that are resistant to diseases, reducing the need for chemical crop protection.
  3. The gross return on investment is generally very high for plant breeding.
  4. The potato industry provides a large amount of employment opportunities.
  5. The Fennoscandian region is well suited for potato cultivation. This crop has the highest yield per hectare of all food crops in Sweden.
  6. Existing cultivars need frequent fungicide treatments and are not adapted to the long days in the summer.
  7. Potato is an essential component in the Swedish cuisine and the Swedish culture.

Once you have a new potato variety, and want to test and commercialize it, it might be a good idea to collaborate with an established plant breeding company.

– The advantage of this would be that the testing of cultivars can be done on a larger scale and more efficiently. This kind of collaborations could provide access to an infrastructure that would not be available otherwise. The payment for these services could take different forms. In Norway the plant breeders at Graminor have an agreement with the private partner Agrico, giving Graminor the right to market the cultivars at a national level while Agrico has gained the right to market the cultivars abroad, says Dennis Eriksson.

The plant breeding company Graminor is largely financed by the state but it also has private part-ownership.

More information: Dennis Eriksson, +46 (0)73-566 95 22, dennis.eriksson@slu.se

Eriksson, D., Carlson-Nilsson, U., Ortíz, R., & Andreasson, E. (2016) Overview and breeding strategies of table potato production in Sweden and the Fennoscandian regionPotato Research, 1-16.

Compostable plastics from potatoes

Researchers have developed a new sustainable material from potato starch – a material that can replace the plastics we use today. The starch comes from a genetically modified potato. Starch molecules in this potato have more of the long chains of glucose that give the starch fiber-like properties.

”It’s soft, not so stiff, and it has a high potential to become something important in the future.”

Researcher Mariette Andersson describes the material that she and her colleagues have made from the starch of a genetically modified potato. This plastics can be composted after using it. Furthermore, the starch has now been used as a part of a composite material. By tailoring mixtures of plant proteins and starch, molecularly and biochemically, one can design sustainable materials for various uses including packaging and plastic film.

In two studies Mariette Andersson and colleagues have tested how this particular potato starch works with proteins from wheat (gluten, gliadin and glutenin which are possible components of the new material). The idea is to develop a stretchable and strong material. They used either glycerol or glycerol + water as plasticizer and extruded the plastics at two different temperatures, 110 °C and 130 °C. In the analysis, they could see that the different proteins reacted in different ways in combination with the starch. In some cases, the material became relatively soft and flexible, and in other cases, stronger and less soft.

The higher temperature induced a higher degree of protein cross-links. With glycerol + water as plasticizer, the starch got improved gelatinous properties, and the material became stronger, more stretchable and easier to process (compared to using only glycerol).  

They also tested what happened to the protein structure at the nanometer level (a level that is one millionth of a millimeter), the mechanical strength of the plastics, and if the material let oxygen molecules to pass through. Some of the gliadin molecules adopted an unusual hexagonal structure in mixtures with starch, and this structure made the material stronger. The combinations of protein + starch worked well as an oxygen barrier.

Ordinary potato starch, consists of molecules with both short and long chains of glucose. The starch molecule amylose has long linear chains of glucose while the amylopectin molecule has a highly branched structure. Native potato starch contains 20-30 percent amylose and 70-80 percent amylopectin.

Using biotechnology, the researchers decreased the levels of two enzymes regulating the branching of starch molecules in potato. This modification increased the glucose chain length of the amylopectin molecules. Thanks to this, the starch got the fiber-like properties that make it suitable as a component of a new environmentally friendly packaging material.

Researchers at the Swedish University of Agricultural Sciences, KTH Royal Institute of Technology, Innventia AB, MAX IV Laboratory in Lund and Institut Polytechnique in France did this study with funding from Mistra Biotech, TC4F, Lyckeby Starch AB, Formas and Partnerskap Alnarp.

More information: mariette.andersson@slu.se, +46 (0)40-415541 and ramune.kuktaite@slu.se, +46 (0)40-415337

Muneer, F., Andersson, M., Koch, K., Hedenqvist, M. S., Gällstedt, M., Plivelic, T. S., Menzel, C., Rhazi, L., & Kuktaite, R. (2016). Innovative Gliadin/Glutenin and Modified Potato Starch Green Composites: Chemistry, Structure, and Functionality Induced by Processing. ACS Sustainable Chemistry & Engineering.

Muneer, F., Andersson, M., Koch, K., Menzel, C., Hedenqvist, M. S., Gällstedt, M., Plivelic, T.S., & Kuktaite, R. (2015). Nanostructural morphology of plasticized wheat gluten and modified potato starch composites: relationship to mechanical and barrier properties.Biomacromolecules, 16: 695-705


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