When a disease pathogen enters a field, it's pretty much there to stay, says Bob Harveson, Extension plant pathologist, University of Nebraska-Lincoln. "These diseases, once they're established in the field, they're not really going to go away," Harveson explained. "Diseases are always there, to a certain extent. The levels may fluctuate, but it's dependent on the environment."
Don't wait to re-evaluate
It's always nice to reap a better-than-expected yield, as many sugarbeet farmers experienced this year. Success can be sweet – but that's no excuse to assume a high-yielding variety will bring similar results in the years that follow. Even if growers achieve record yields and sugar content or effective disease management, fields should be re-evaluated every year as conditions can change.
Disease pathogens and insect pests can travel and evolve unexpectedly, which can catch growers off-guard. Rotations with corn crops also leave sugarbeets more susceptible to Rhizoctonia.
Ruppal says sugarbeet co-ops around the country strongly consider disease tolerance when approving varieties for their member farmers because pathogen vectors vary from year to year and can be impossible to predict.
"During OVTs, the co-ops are looking at multiple characteristics. Of course, yield and sugar are very important, but they also weigh disease tolerance traits just as heavily, if not more," Ruppal says. "That goes for Rhizoctonia, Cercospora and Aphanomyces in the Red River Valley; Rhizoctonia and Fusarium in Colorado and Nebraska; and powdery mildew and curly top in Idaho."
Warm weather will wane
While many crop growers across the country experienced frustrating issues with the unusually hot, dry summer of 2012, the weather was advantageous for sugarbeet farmers. Disease pathogens were kept relatively dormant in the absence of high humidity and the dry soil made harvesting much easier.
"It was a lot hotter, a lot drier this year. We didn't see some diseases as readily as we often do because the environment was not conducive for many of them to occur," Harveson says.
"Diseases like Cercospora need a combination of hot weather and humidity to thrive," he adds. "A warm, dry growing season was a nice gift for sugarbeet farmers, but they certainly shouldn't expect any consistency."
Changes in weather, soil conditions and disease pathogen activity can significantly reduce yield and sugar content, but "selecting the right variety can be the critical start to a successful crop," Ruppal says.
Although sugarbeet farmers would like to think this past season is the beginning of a new weather trend, experts report it is unlikely next summer will bring the same experience.
Although sugarbeet farmers won't need to head into the wilderness or stand in holiday-sized lines for next year's sugarbeet stand – 'tis the season for searching!