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Whither the weather?

If this is global warming — bring it on!

That was a common response to last week’s record-setting temperatures across southern Manitoba —at least initially.

Who could complain about a daytime high of 11 C the first week of January?

But at the same time few could deny a sense of unease over a less-than-white Christmas, fields with no snow and the below-normal precipitation in these parts since last spring’s record-setting soggy spring.

One had to wonder whether we’ll be as bullish on these balmy temperatures in the future or whether we’ll look back on the winter of 2012 as the year we came to realize the climate-change forecasts weren’t just a bunch of blarney.

Historians like to remind us this part of the world is more prone to drought than drowning. But it’s also true that periodic flooding is a fact of life.

And the climate-change forecasts have never wavered from the prediction that weather extremes will become the norm, that total precipitation will be reduced but heavy precipitation events will become more common.

We’re not about to stick our necks out and say definitively that the climate is changing, but we will make the observation that the previous paragraph pretty much sums up the weather over the past year in Manitoba.

And it’s worth noting that the British government’s Met Office and the University of East Anglia is predicting 2012 may be one of the top 10 hottest since 1850, with global temperatures expected to be almost .5 C warmer than the long-term average.

The World Meteorological Organization lists 2010 as its warmest year on record, and all of its 12 warmest years fall between 1998 and 2011.

We do have confidence in saying that production systems that can accommodate highly variable weather patterns have never been more important. And we question whether plant-breeding research is fully factoring those uncertainties into long-term breeding.

We’re not alone.

Charles Walthall, national program leader for climate change at the USDA Agricultural Research Service (ARS), was quoted in a recent DTN report as saying rising carbon dioxide levels in the atmosphere could lead to more invasive species, insects and pathogens. Weeds, for example, which are free to evolve according to environmental triggers, respond aggressively to the higher carbon dioxide levels, the report says.

“We have not bred the variety of crops to take advantage of higher carbon dioxide in the atmosphere,” Walthall is quoted as saying. “Weeds, in their genetic freedom, for a large part have. That’s why we are seeing larger, stronger weeds and vines.”

2013 is the silver anniversary of the discovery of herbicide-resistant weeds — a dubious distinction at best. Under intense selection pressure based on continued use of the same products for the same problem species, it takes less than a decade for weeds to adapt to overwhelm those active ingredients. Even the mighty glyphosate, once considered infallible, is becoming increasingly ineffective.

One ARS experiment, which looked at predicted CO2 levels in 2050, showed intense weed growth that took four times the volume of herbicides to control, Walthall said.

What does that do for the cost of farming the way we do it in North America today?

As well, Walthall said rapid growth under high levels of CO2 results in some plants failing to absorb adequate levels of nitrogen, which makes it more susceptible to stressors.

The point is, the environment in which farmers must grow their crops is capable of rapid evolution.

Meanwhile, our current approach to plant breeding, which is focused on selecting for specific traits, and producing genetically stable varieties that cannot evolve in the field because they are hybridized and/or protected under intellectual property laws may not be able to keep pace.

Governments need to focus research priorities, and private-sector plant breeders must achieve a return on investment. The industry has seen some dramatic yield breakthroughs as a result of these efforts and it appears so far, there is enough value in the system to ensure everyone gets a cut.

But the decline of open-pollinated crops and increasing limits on farm-saved seed should be a cause for concern. Maybe we need to take a lesson from the weeds, or from the African farmers who have maintained “landrace” varieties — groups of cultivars which have common end-use characteristics, but which individually have different resistance to environmental stress. Whether it’s a year with drought, disease or insects, at least some of the plants survive.

Given a future which seems even less stable than the past, it would seem prudent for all research programs, particularly those managed by farm commodity groups, to devote at least a portion of their budget to these efforts.

About the author

Vice-President of Content

Laura Rance

Laura Rance is vice-president of content for Glacier FarmMedia. She can be reached at [email protected]



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