Sustainable Agriculture with Perennial Grain Crops

Conversations about global food security are often framed around major 21st century agricultural challenges. Many ask “Is it possible to feed the world sustainably?”. Only some understand that such question implies addressing the interwoven global challenges of food security in a holistic, multi-strategic and context appropriate way. In a nutshell, such challenges are:

• Demand for agricultural production will continue to rise as population grows and consumers eat more meat;
• Resources such as soil, water and oil -not only used for fuel but also for its derived fertilizers, herbicides and pesticides-, are all becoming scarce;
• Agriculture is progressively putting pressure on ecosystems by polluting waters, destroying habitat and emitting greenhouse gases;
• Adapting to climatic variability is also a major concern.

Researchers have proposed general approaches to solving these challenges that must be deployed simultaneously:

• Stop expanding agriculture
• Close yield gaps
• Increase agricultural resource efficiency
• Shift diets away from meat
• Reduce waste

To ensure the globe’s health, the world must meet increased food demands all while drastically cutting agriculture’s footprint. That’s when Perennial grain crops come in, as a specific agricultural tactic in line with the general approaches stated above. 

Imagine: “an agricultural system with the ecological stability of the prairie and a grain yield comparable to that from annual crops" –The Land Institute
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Today 70% of global croplands are occupied by cereals, oilseeds and legumes. They are all annuals, which means they die after reproduction and must be grown anew from seed every growing season. They are usually cultivated with resource-intensive methods, which come along having adverse effects.
However annual grains have become staples over agriculture’s history through millennia of breeding and domestication due to desired traits such as: providing high yields of calorie and protein; being easy to transport and store; being relatively imperishable; and also, their greater market value often pressures farmers to grow them over perennial plants.
On the other hand, perennial plants have environmentally appealing traits, which are somewhat inherent to their more extensive root system, their better ground cover and their longer life span. Compared to annuals, perennial plants:

• Are more efficient at using water and nutrients (which decreases the need of inputs and their related costs)
• Sequester more carbon and protect soil from erosion (which is good for the soil health and climate regulation)
• Are more capable of being sustainable crops on marginal lands
• Are more robust and resilient to climatic variability

The list can go on. Since the 1930’s plant breeders, ecologists and agronomists have been exploring the idea of merging the benefits of annual grains with the benefits of perennial plants. Such is the great Perennial Grains promise: developing perennial versions of the major grain crops that can, at the farm scale, offer farmers more opportunities to meet their income needs while protecting their natural capital; and, at the global scale, meet food demands while improving critical ecosystem services.

“Perennial farming can reduce erosion rates by up to 50 percent” - Pimentel et al., 1997
​“Annual crops lose up to five times more water than perennials”- Glover et al., 2010

Perennial crop developers essentially use conventional breeding methods: direct domestication of wild plants or hybridization of existing annual crop plants with their wild relatives. Researchers at The Land Institute in Kansas are playing a major role on this matter. The photo bellow shows the root system of the perennial wheatgrass they’ve developed compared to its 'equivalent' annual winter wheat. 

Source: The Land Institute

However, research and breeding programs to develop perennial grain crops are still in young stages. These programs may not produce wide scale impacts in farmers' fields for another 15 to 20 years. A major challenge in 'perennializing' grains is that it often comes with the trade off of reduced yields. This is being dealt by reducing their lifespan and finding their appropriate location for production (some perennial grains may not be viable/competitive in highly productive areas, however they might be more appealing in underperforming agricultural marginal lands).

Perennial grains represent a paradigm shift in agriculture and hold great potential to move towards sustainable production systems. However, the main lesson learned lies around valuing perennial characteristics to address the challenge of global food security and environmental sustainability: introducing existing perennial plants to complement annual agricultural systems without the need to breed new perennial grain varieties should not be overlooked.

Whether if it is agroforestry, permaculture or any other name for a food production system that integrates perennials intentionally, such systems are looking beyond the reductionist benefits of annual monocrops and are including the care for the earth and each other, over time, and in a fairer way. 

-By Anna Zisa
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References
FAO. 2013. Perennial Crops for Food Security. Proceedings of the PAO Expert Workshop. Biodiversity & Ecosystem Services in Agriculture Production Systems. http://www.fao.org/3/a-i3495e.pdf

Foley, J.A. Ramankutty, N., Brauman, K.A., Cassidy, E.S., Gerber, J.S., Johnston, M., Mueller, N.D., O’Connell, C., Ray, D.K., West, P.C., Balzer, C., Bennett, E.M., Carpenter, S.R., Hill, J., Monfreda, C., Polasky, S., Rockström, J., Sheehan, J., & Siebert, S., Tilman, D. & Zaks, D.P.M. 2011. Solutions for a cultivated planet. Nature. 478: 337–342. http://www.nature.com/nature/journal/v478/n7369/full/nature10452.html
Glover, J.D., Cox, C.M. and J.P. Reganold. 2007.Future of Farming: A return to roots? Agriculture. Scientific American. Vol. 86. https://landinstitute.org/wp-content/uploads/2014/04/Glover-et-al-2007-Sci-Am.pdf

Kunzing, R. 2011. The Big Idea: Perennial Grains. National Geographic. Web accessed Oct 14th 2015: http://ngm.nationalgeographic.com/2011/04/big-idea/perennial-grains-text

Mission 2015. The Advantages of Perennial Agriculture. http://web.mit.edu/12.000/www/m2015/2015/perennial_agriculture.html

Pimentel, D., Wilson, C., McCullum, C., Huang, R., Dwen, P., Flack, J., . . . Cliff, B. (1997). Economic and environmental benefits of biodiversity.Bioscience, 47(11), pp. 747-757. http://udel.edu/~gshriver/pdf/Pimenteletal1997.pdf
The Land Institute. www.thelandinstitute.org