The critical element for sustainable agriculture

  Photo: Thinkstock

Photo: Thinkstock

Written by Gerald Pilger

In the business world, there’s a term to describe an event that completely changes an existing industry or market. It’s called a disruptor, and it changes how we think, work, and do business.

It can be argued that agriculture has gone through three major disruptions in the last century: the mechanization of farming; the arrival of chemical fertilizers and pesticides; and the genetics revolution which introduced new varieties, new breeding tools, and genetic engineering.

Innovations in each of these fields changed the way we farm, and each resulted in increased productivity and efficiency.

We are now on the cusp of the fourth major disruptor: biology. More specifically, advances in microbiology are opening the eyes of farmers, scientists, those in ag industry, and even venture capitalists to the world beneath the soil surface. And what they are finding down there is truly amazing

In 2012, the American Academy of Microbiology produced a report entitled “How Microbes Can Help Feed the World.” That report claimed that attention to microbiology could “increase the productivity of any crop, in any environment, in an economically viable and ecologically responsible manner.”

More than just a medium that anchors and feeds the crop, soils are teeming with life. Pick up a handful of healthy fertile soil and you will be holding billions of living organisms in your hand (see chart).

In fact, an acre of healthy soil can contain from a few hundred to thousands of pounds of microbial biomass.

And that isn’t all. According to Dr. Mathew Wallenstein, associate professor at Colorado State University, this handful of soil will have tens of thousands of different microbes. “Any soil will have as much microbial diversity as the diversity of life you would find in a tropical rain forest,” says Wallenstein.

Science reveals that these tiny organisms play a huge role in the growth of plants. Some convert organic matter into nutrient forms that a plant is able to utilize. Others help protect the plant from disease and pests, and some microbes even communicate with plants, enabling the plant to deal with environmental stresses and reduce the impact of drought, for example.

“Microbes are critical to sustainable agriculture,” Wallenstein says.

It is the discovery of such symbiotic and complementary relationships that is leading scientists to turn their focus from plant health to soil health. For example, instead of just feeding the plant, farmers are being encouraged to feed the microbes necessary for the conversion of chemical fertilizers into nutrients which the plant can take up.

Scientists are also trying to isolate microbes which enable a plant to resist pests, and then develop a process for growing these desired agricultural biologicals, packaging them, and devising a process which farmers can use to introduce these organisms into their cropping system.

In many ways, this idea is not new. We have known for decades about the value of nodulation for legumes to fix their own nitrogen. Farmers inoculate crops such as alfalfa, soybeans, peas, and lentils to ensure maximized N fixation.

But it is only recently that science has learned the impacts that so many other organisms have on plant growth. And, in spite of such advances in the study of soil microbes, scientists are still only able to grow about one per cent of known soil organisms in a lab setting.

Support soil microbes with good farming practices

Many farmers are likely hesitant to purchase new, relatively unproven biological products, especially given current low grain prices. However, all farmers can benefit from the research into soil biology without even purchasing novel soil amendments.

Dr. Bobbi Helgason, soil microbiologist with Agriculture and Agri-Food Canada, has studied the impact of farming on soil health and the microbial community. She says farmers who have adopted modern, sustainable farming practices benefit from increased microbe populations and healthier soils.

“No-till farming has had a huge impact on soil health,” Helgason says. “It has increased the organic matter in the soils, which means more food for microbes.”

Helgason also points out that farmers who use cover crops also increase food supply for microbes.

Also, today’s farmers have introduced a wider diversity of crops into their rotations which encourages diversity in the microbial population.

Helgason points out that all soils contain a huge number of diverse microbes, so the addition of a jug of a biological product is merely a drop in a very large bucket. It is just as important to feed the native microbes in your soils as adding a few more. The first step toward increasing soil health and the microbe populations is to learn more about the importance of microbes to the soil and plants. Then, follow a sustainable farming system that supports microbes.

SOURCE: Country Guide