Researchers look to microbes to balance soil ecology

Scientists examine the impact on greenhouse emissions of removing carbon-rich crop residues from farm fields

HARROW, Ont. — Harnessing soil ecology for the benefit of agriculture is the central objective for one of the new research scientists at the Harrow Research and Development Centre.

“We’re looking to manage microbes to develop practical cropping management solutions,” Lori Phillips told the centre’s open house Sept. 10.

“We need to think of the soil as an ecology. If, for example, you suppress one thing that’s happening, something else will come in to fill the void.… For a lot of things it’s about finding the right balance.”

One area of research revolves around the practice of removing carbon-rich crop residues from farm fields.

“Under a minimum tillage regime, as you remove stover, you get increased nitrous oxide produced because you’re favouring soil organisms that create nitrous oxide, but that’s a statement that’s full of caveats.”

For example, removing corn stover for such uses as the production of cellulosic ethanol can affect the microbial community in farm fields. However, so does soil type, climatic influences and other factors such as the timing and type of farming practices, she said.

Phillips hopes to eventually provide the type of quantitative advice that farmers find useful.

Preliminary research in the sandy loam at Harrow indicates that 75 percent of corn stover can be removed in a minimum-till scenario without an undue increase in the emission of nitrous oxide.

Nitrous oxide is a greenhouse gas with a global warming potential estimated to be 298 times greater than that of carbon dioxide.

“One of the reasons we cannot predict with 100 percent accuracy the greenhouse gases being emitted is because we’ve neglected to include the biological component in the soil,” she said.

Phillips also hopes to help farmers establish optimum nitrogen application rates, taking into account the microbial contribution. One important consideration in this is the timing for cover crop incorporation.

A third project concerns the establishment of base lines for soil biodiversity molecular techniques. She is leading the project in Ontario for Agriculture Canada. Natural Resources Canada and Environment Canada are also involved.

“You cannot monitor what’s going on in our soils until you know what’s out there already,” she said.

“It’s important work. Essentially, microbes perform all the ecosystem services we need to survive.”

Phillips, one of just five microbial ecologists in Canada, spent five years working for the Australian state of Victoria’s environment and primary industries department. She earned her PhD at the University of Saskatchewan.

Della Johnson, director of the research and development centres in Harrow and London, Ont., said Phillips is one of seven new scientists hired within the past year.

Julia Mlynarek, a field entomologist, came on board in September from the University of New Brunswick in Fredericton.

Rose Labbé, originally from Ontario’s Essex County, is a greenhouse entomologist previously employed at the University of Michigan.

Owen Wally is a field pathologist specializing in soybeans and dry beans. Originally from Manitoba, he worked in the United States before coming to Harrow.

An entomologist and a protein biochemist have recently been hired at London, which includes the Vineland Station, and a nematologist is expected to join the team before year’s end.

Johnson describes the ongoing investment in the London and Harrow centres as stable.

“Our researchers are passionate about our work. We do what we can for farmers to allow them to be more profitable.”

The Harrow centre has a broad mandate with its focus on greenhouse vegetables and ornamentals and field crops such as corn, soybeans, wheat and vegetables. The development of weed and pest management strategies is part of this along with research pursuing sustainable strategies in nutrient efficiency, soil and water conservation, cover crops and soil quality.

The centre is also home to the Canadian Clonal Genebank for fruit and berries.

Patrick Girard, a spokesperson for federal Agriculture Minister Lawrence MacAulay, said 14 new Agriculture Canada researchers have been hired in the last six months.

“The hiring of researchers, including those at Harrow, are part of AAFC’s on-going staffing plans,” he said. “AAFC plays a key role in long-term and exploratory early-stage research that is not immediately commercially viable and that carries high risk with uncertain returns. In addition, the department has the infrastructure, expertise and financial stability that allow long-time horizons and research that targets the public good.”

Girard said $37.6 million was budgeted for the 2016 fiscal year to upgrade Agriculture Canada’s 20 research facilities and another $30 million was designated for advanced genomics.

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