Your Reading List

Biologicals in agriculture: what’s old is new (and improved)

Farmers have a centuries-long tradition of using biologicals whether they called it that or not

Inoculants to encourage pulse crops to nodulate are a familiar form of biological product.

The term ‘agricultural biologicals’ conjures up images of white lab coats and test tubes.

But the practice itself — deriving benefits from naturally occurring micro-organisms — predates the scientific method itself.

Centuries ago, long before they knew anything about rhizobia or nitrogen fixing, farmers were reaping the benefits of the process by rotating legumes in with their other crops.

Science has come a long way since then. And as the boffins in white lab coats learn more and more about the microscopic processes that go on in the root systems of plants, their counterparts in the business world are creating a technology boom in the field of biologicals.

With his background in agricultural science and business, Jarrett Chambers has a bird’s-eye view of this technological revolution. Chambers is an expert in the interaction of plant nutrients and the integration of biostimulants in plant physiology. He founded ATP Nutrition, which is now one of the largest plant nutrient suppliers in Canada, and was one of the speakers at this year’s virtual Farm Forum Event held early this winter.

“People talk about how there are billions and billions of organisms in a spoonful of soil. That is true,” Chambers said. “Biologicals represent 60 per cent of the biomass that exists on Earth.”

In terms of how biologicals relate to crop production, there are the obvious examples, like the nitrogen-fixing rhizobia converting atmospheric nitrogen into a form that the plant can use. There are organisms in the soil that convert ammonia into nitrates. Other organisms take phosphate and phosphorus and solubilize them to make those elements available to the plant.

These organisms are in a symbiotic relationship with the plant that can work to improve overall soil health.

“As the plant above ground undergoes photosynthesis and creates food for the root system, that root system proliferates. As it proliferates, it excretes out various compounds into the rhizosphere which then feeds the organisms,” Chambers said.

In return, the organisms supply nutrients to the plant that feeds the above-ground portion of the plant.

Chambers went on to explain the two main ways industry is helping to capitalize on these microscopic interactions. The first one is the organism itself. Essentially, the organism is multiplied through fermentation and then is introduced into the rhizosphere.

The second way is identifying and synthesizing the beneficial byproducts of what the organism excretes during its interaction with the plant.

“These are the metabolites,” Chambers said. “A metabolite is a collection of the various amino acids, enzymes, peptides, and organic acids produced by the organism. These can all be either finished products or intermediary products.”

There are seven main groups of metabolites that are produced.

The first two are low molecular weight organic acids and amino acids. Both of these increase phosphorus solubility; increase the mobility of inorganic nutrients like copper or zinc, and; support a healthy rhizosphere.

There are also non-protein amino acids that facilitate pathogens and damage resistance preparedness.

The fourth group is the peptides that stimulate soil microbial metabolism and help with stress resistance.

Next there are the phenolic acids that attract bacteria associated with the rhizosphere, mediate plant stress responses and support lignin accumulation and salinity tolerance.

The sixth group is the flavanoids, which facilitate colonization by nodulating bacteria that helps with nitrogen fixing.

Finally, the polyamines reduce the impacts of drought stress.

Chambers wrapped up his presentation by encapsulating the main benefits that biologicals and metabolites offer. They can help reconstitute the soil; they can increase rooting and vegetative plant growth; they reduce the impacts of stress; they improve nutrient-use efficiency, and; they ultimately improve crop performance.

“And of course, at the end of the day, that’s what really puts the bushels in your bin,” he said.

About the author



Stories from our other publications