Microbes vs. Genetic Modification

Photograph by Martin Oeggerli, National Geographic

Adapting microbes that dramatically increase crop yields while reducing demand for fertilizers and pesticides through selective breeding or genetic engineering could be cheaper and more flexible than genetically modifying plants themselves, says an author of a report.

Microbes, such as beneficial bacteria, fungi and viruses, could be produced locally for smallholder farmers to significantly improve food security and incomes in developing regions, believes Ann Reid, director of the American Academy of Microbiology and co-author of a report published by the organization last month (27 August).

"Genetic modification of crop plants, which has seen a huge investment, is closed to all but the biggest agricultural companies," she tells SciDev.Net. "Optimisation of microbes could be done at the level of the local community college and is much more obtainable for a smallholder farmer."

Her comments echo the findings of the report — the product of an expert meeting in 2012 — which underscored the significant impact microbes could have on food production by increasing crops' absorption of nutrients, resistance to disease and environmental stresses, and even improving flavor. As well as to accentuate naturally occurring traits such as the secretion of pest-killing toxins or nitrogen-fixation, the modification of microbes is often needed to allow them to be grown in large numbers out of their natural environment.

For example, researchers in Colombia could only produce large quantities of a fungus that improves the nutrient absorption of cassava once they bred a strain of that fungus that was capable of growing on carrot roots. Recent technological developments in rapid DNA sequencing, imaging and computer modeling can help provide further solutions, as well as building a greater understanding of the complex environment that microbes themselves need to flourish, the report says.

These advances raise the possibility that, within two decades, microbes could increase food production by a fifth and reduce fertilizer demands by the same proportion, it finds. But to achieve this ambitious goal, the research community must engage in curiosity-driven basic research, develop even cheaper sequencing techniques, and establish a process to move discoveries from the lab to the field, it says. Reid adds that, unlike genetic modification, which requires farmers to regularly buy improved seeds, microbes may be able to stay in the soil indefinitely.

But larger universities are still needed to drive more-complex areas of investigation, which inevitably requires funding, she says. "We wanted to get the word out that this could be a big-bang-for-your- buck area for funding agencies."

http://www.enn.com/ecosystems/article/46513