Seed News


European Agricultural Policy Goes Down the Tubers

Date Posted: June 12, 2012

(June 7) To the Editor, Nature Biotechnology:

A news story in the March issue1 notes the announcement by Ludwigshafen am Rhein, Germany–based agrochemical company BASF of a discontinuation of its breeding efforts for genetically modified (GM) crops adapted to European conditions. The multinational is closing its agricultural branch in Europe and choosing instead to focus on the American and Asian markets; meanwhile, BASF's chemical manufacturing facilities in Europe remain intact.

This is the latest example of the combination of overly restrictive legislation on genetically modified organisms and a deep political and market mistrust that has had a profound chilling effect on the innovative environment for European agricultural research. The flight of BASF from Europe, though, is likely to have several other repercussions for European agriculture and food availability that have yet to play out, particularly with respect to potato production.

Crop cultivars developed by BASF include, but are not limited to, potato varieties with altered starch qualities meant for industrial starch production. The company developed several amylopectin-rich cultivars, including Amflora, Amadea and Modena (transgenic for either an antisense or RNA interference construct of granule-bound starch synthase from Solanum tuberosum that suppresses expression of the enzyme). The first of these, Amflora, is one of only two GM products that have been approved for cultivation by the European Union (EU).

In addition, BASF has bred another potato cultivar Fortuna, which is transgenic for the Solanum bulbocastanum resistance genes Rpi-blb1 and Rpi-blb2, and shows enhanced resistance to the fungus-like oomycete Phytophthora infestans, which causes potato late blight.

Because of its rapid spread and devastating effects on potato crops, P. infestans is considered to be one of the most destructive pathogens in agriculture worldwide (and was notoriously the cause of the potato famine in Ireland in the nineteenth century. A P. infestans attack on potato crop foliage often leads to complete yield loss and a rapid spread of the pathogen to neighboring fields. To avoid such damage, farmers implement intensive fungicide spraying programs across Europe, a procedure that now must also be expanded to tomato plantings as the plant host range of P. infestans has expanded over time to include these vegetables.

Official data of yield losses incited by P. infestans on a global scale are generally lacking. However, during epidemic years, the potato crop losses are commonly estimated to exceed 75% without any crop protection6. The International Potato Center (Lima, Peru) estimates the annual value of these losses to be $3–5 billion, excluding losses from tomato infestations.

Potato has a narrow breeding base, is highly heterozygous and suffers from acute inbreeding depression, making introduction of resistance traits to market-adapted genotypes difficult. Attempts to introduce various resistance genes from wild Solanum species have been undertaken in the past century, but P. infestans has evolved much faster, enabling it to counteract these breeding efforts.

This extreme pathogenic potential reflects the remarkable makeup of the pathogen genome9, which contains a huge repertoire of effector genes that are exploited by P. infestans to rapidly adapt to new cultivars and even to fungicides. In this context, introduction of BASF's Fortuna GM cultivar represented a novel and rapid strategy to combat late blight disease.

From a global perspective, potato production is undergoing major changes. Until the early 1990s, most potatoes were grown and consumed in Europe, North America and countries of the former Soviet Union. Since then, there has been a dramatic increase in potato cultivation and demands in Asia, Africa and Latin America, where the production increased from ~30 million tons in the early 1960s to more than 180 million tons in 2007 (http://faostat.fao.org/).

The per capita consumption of potatoes is still highest in Europe, followed by North America and Asia, but the crop is steadily becoming more popular also in Africa. With these overall increases, and with the geographic shifts in production patterns, increased problems with late blight are anticipated because the disease easily spreads between geographic regions and continents by means of infected tubers.

The potential value to EU agriculture of a P. infestans–resistant GM potato variety should not be underestimated. For Sweden alone, which accounts for only 1.3% of the EU area under potato cultivation and 1.4% of the harvest (http://epp.eurostat.ec.europa.eu), the potential economic value to the country from a complete shift to a GM late blight–resistant potato has been estimated at ~12 ($16) million annually.

Factors considered in calculating this number include effects on the producers' work force and capital; demand for fertilizers, agrochemicals and fuel; cost of keeping GM crops separated from conventionally or organically grown crops; and environmental effects that are known, or that can be presumed, to occur.

But in addition to the economic penalties of turning its back on these new varieties of potatoes, the EU faces several other strategic consequences from BASF's decision to pull up stakes and move on. First, instead of being able to adopt the GM Fortuna cultivar and reduce the use of harmful chemicals, European farmers must rely on the continued use of fungicides that are far from environmentally friendly. Ironically, this choice obstructs further expansion of organically produced potatoes and tomatoes because adopting the GM Fortuna cultivar in 'conventional' agriculture could have led to reduced disease pressures benefitting alternative farming systems.

Second, Europe is the leading potato-consuming continent on a per capita basis. Most likely the continent will now become increasingly dependent on the import of potatoes from other continents, as the chemical warfare against P. infestans inevitably becomes less successful in Europe. These imported potatoes are likely to be GM Fortuna, anyway, so Europe is still left with the problem of tackling political resistance against it or any other GM crop.

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