Adapting Mycorrhizal Fungi To Improve Yields of Globally Important Crops

In 2008, over 900 million people (several times the population of the USA) were suffering chronic hunger. Every year, approximately 5 million people die of malnutrition. Of these, almost 3.5 million are below the age of 5 and almost all deaths occur in so-called developing countries. The irony is that enough food is currently produced to feed the worlds human population. Unfortunately a much larger global food crisis lies ahead. The UN conservatively estimates that by the year 2050 the global human population is expected to reach over 9 billion. Feeding such a population represents an unprecedented challenge since this goes greatly beyond current global food production capacity.

To meet this challenge, major changes have to occur to agriculture bringing in new technologies to increase crop yields and significantly reduce costs of food production. Scientists, and especially microbiologists, must play a key role in the development of such new technologies. Many beneficial microorganisms exist that form symbioses with plants. By far the most common of these are mycorrhizal fungi. When plants make symbioses with mycorrhizal fungi they grow larger. This is because the fungi acquire the essential nutrient phosphate for the plant. Despite their beneficial effect, mycorrhizal fungi are rarely used in agriculture. In most tropical soils, plants have enormous difficulty in obtaining phosphate and so farmers have to spend a huge amount of money on phosphate fertilizer. In the tropics, farmers have to add much more fertilizer than in temperate regions and a very large amount of the cost to produce food is the cost of phosphate.

Mycorrhizal fungi live in almost all soils and with most plants. One very unusual feature of these fungi is their genetic variation. This has deterred many researchers from working with these fungi. In this presentation I will show how we have managed to manipulate the natural genetic variation in mycorrhizal fungi to produce novel mycorrhizal fungal lines that can greatly increase the growth of globally important crops such as rice. Coupled with biotechnological breakthroughs in how to grow mycorrhizal fungi cheaply and cleanly, our findings are likely to result in real applications with important food crops in the tropics in the very near future. The work I will present takes us from the lab in Switzerland, to large-scale agricultural systems in Colombia. I will demonstrate the potential of using these fungi to maintain food production in the tropics, while greatly reducing the application of phosphate fertilizers; thus leading to potentially lower food production costs in the tropics, reducing poverty and hunger. While our applied research is focused on Colombia it could be applied in many other tropical regions of the world. I show only one example of how the unusual biology of a microorganism can be a key to better food production. My message to microbiologists is that we indeed have the potential to contribute to alleviating the global food crisis.

For more information: http://people.unil.ch/iansanders/