Prairie crop breeding programs are producing more and better varieties to protect crops from pests such as diseases, insects and weeds. But it's critical to use these varieties as part of integrated control strategies to prevent costly breakdowns in genetic pest resistance.

"The bottom line is, if you do the same things over and over again, pests are going to find a niche in any system," says pathologist Dr. Kelly Turkington of Agriculture and Agri-Food Canada. "Varieties with resistance to a pest are a great tool, but even they need to be managed carefully, in a coordinated way with other tools, to minimize the risk of the pest population adapting to overcome that resistance."

Varieties with pest resistance are often mentioned as a valuable alternative to crop protection products, primarily for their cost and environmental benefits. But when relied on too heavily, the pest resistance in varieties is just as susceptible as other control tools to being overcome by adapting pest populations.

That's why researchers and other farmer advisors increasingly tout the benefits of integrated control strategies, to balance the control workload, extend the lifespan of all control tools and keep resistant pest populations at low levels.

"Look at the breakdown of scald resistant barley varieties in Alberta," says Dr. George Clayton, an AAFC integrated crop management researcher. "Look at the build-up of resistance to Group 1 and Group 2 herbicides. Look at the recent problems with Ascochyta blight in chickpea. We simply can't afford to be relying on single solutions, or even in a lot of cases double solutions. We need to take advantage of all the tools at our disposal, and take a more sophisticated approach using integrated strategies."

Further perspective on the need for integrated pest control, from Turkington and Clayton, along with colleague Dr. Neil Harker, is featured in the April edition of Western Grains Research Magazine, now available at www.westerngrains.com. Western Canadian wheat and barley growers are major investors in breeding research through the Wheat and Barley Check-off Funds, administered by WGRF. The Research Magazine offers "Ideas and issues for farmer research investors."

It's important to remember a pesticide can never do a complete job, says Harker, a weed scientist with AAFC. "There are always leftovers. Even if you get great results with a pesticide after year one, year two or even year three, if you keep relying on that single fix you're effectively supporting the build-up of resistance to the control in the pest population. You might not see it right away, but there's no doubt it's coming."

Prairie crop breeding programs are helping to slow the build-up of resistant pest populations by developing varieties that incorporate multiple sources of resistance to the pest, notes Turkington. "That's not any easy thing to do, but we're seeing more of it as variety development becomes more sophisticated and effective."

Even if the sources of resistance are not in the same variety, producers can often also take advantage of multiple sources of resistance by rotating varieties with different sources, says Turkington. "This is another good way to keep pest populations off balance. Again, breeders are continually making progress to introduce new sources of resistance, and it's critical we not only take advantage of these but use them judiciously to extend their lifespan."

A key message is that varieties with pest resistance represent one control strategy, but in order to prolong their usefulness, producers should use as many of the other tools for pest management that they have access to, says Clayton. "Certainly crop rotation, prudent use of fungicides when they're needed, clean seed, good agronomics that promote a healthy crop - these are all important to take advantage of."

Part of what's needed is a change in mindset, says Clayton. "We need to see more producers looking at different ways to manage pests, and moving towards integrated crop management strategies. I think there are more producers that are actually taking that approach somewhat. Certainly not everybody, but I think there's more and more all the time."