ISSUE #407

407 - Rhizomania Impacts Yield and Quality


Are strange bright yellow spots showing up in your fields? Quite a few fields in the Red River Valley have fairly severe rhizomania showing up. Affected fields could have reduced tonnage and sugar content.

Rhizomania Identification and Symptoms – Leaves

  • Patches in fields
  • Poor growth
  • Bright, almost fluorescent yellow leaf growth
  • Narrow long leaves
  • Longer than normal and erect petioles
  • Photo #1


I.D. and Symptoms – Roots

  • Stunted tap roots
  • Masses of hairy sideroots or a “bearded” appearance on the tip of the beet
  • Root growth constricted a few inches below the soil – “wineglass” shape
  • Yellow to dark brown discoloration of root tip vascular bundles
  • Photo #2


Rhizomania Control Measures

  • No seed treatments are available
  • Sanitation of field equipment, etc.
  • Planting early minimizes impact
  • Improved field drainage reduces severity
  • Longer crop rotations may help
  • Soil fumigation – but it’s cost prohibitive
  • Resistant variety use
  • Tare soil management

If you suspect you might have rhizomania in a field, contact your agriculturist for assistance making a positive identification. Once rhizomania is found, it’s very important to monitor disease severity changes in the field. Incidence of the disease is most common south of Highway 2 at this time. About 50% of the acreage in southern Minnesota is now planted to resistant varieties.

2002 Phosphorus Fertility Management

Many growers used only starter fertilizer or reduced broadcast P fertilizer rates along with starter fertilizer in 2001. Reports are excellent for early season growth and vigor.

Reduced Production Cost Opportunity

Use of starter fertilizer alone or with reduced broadcast application rates can result in lower fertilizer costs. Shareholders considering changing how they manage phosphorus fertilizer needs for the 2002 crop should consider the following University of Minnesota recommendations.

  • If the soil test level is 12-15 ppm or greater apply no starter or broadcast P205 fertilizer
  • If the soil test level is less than 12 ppm and you fall applied the recommended broadcast phosphorus fertilizer apply no more phosphorus
  • If the soil test level is 8-11 ppm you can use either 3 gpa of 10-34-0 or the recommended broadcast P205 recommendation for crop needs
  • If the soil test level is 7 ppm or less you can apply the broadcast P205 recommendation or 3 gpa of 10-34-0 and only 30-40 lbs./acre P205
  • If the soil test level is 4-7 ppm phosphorus, ONE YEAR of research indicates only 3 gpa of 10-34-0 produced yields equal to recommended broadcast P205 rates

Producers should keep in mind that prolonged use of only starter or low broadcast P fertilizer rates may result in declining P soil test levels. Other crops in rotation with sugarbeets may grow best at soil test levels that are higher than optimum soil test levels for sugarbeets.

NDSU Production Practice Survey

Shareholders should have received the annual NDSU/U of MN Production Practice Survey from Dr. Alan Dexter by now. It’s very important this survey be completed and returned. The survey can also be completed on the ACSC web site at Completing the survey on line is quick and easy.

Why Complete The Survey:

  • Aids in planning research to answer grower problems
  • Helps plan effective educational programs
  • Facilitates obtaining special registrations for needed pesticides
  • Provides early warning signals for emerging problems

Event Date Location

So. MN Beet Sugar Coop. Annual Mtg. December 3, 2001 Willmar Holiday Inn Conf. Ctr.
Minn-Dak Farmers Coop Annual Mtg. December 4, 2001 Fargo Holiday Inn
American Crystal Sugar Co. Annual Mtg. December 6, 2001 Fargo Holiday Inn
RRV Sugarbeet Growers Ass'n Annual Mtg. December 6, 2001 Fargo Holiday Inn
32nd Reserach Reporting Session January 8, 2002 Fargo Holiday Inn
Fargo Growers Seminar January 28, 2002 Fargo Holiday Inn
Wahpeton Growers Seminar January 31, 2002 Wahpeton Eagles
Grand Forks Growers Seminar February 4, 2002 Grand Forks Ramada Inn
Grafton Growers Seminar February 6, 2002 Parish Center
So. MN Growers Seminar February 21, 2002 Willmar Holiday Inn Conf. Ctr.
International Sugarbeet Institute March 13 & 14, 2002 Alerus Center - Grand Forks, ND

Harvest Tip Benefits Shareholders:

More fields than usual have severe late season weed problems in 2001. Strongly consider using a flail shredder ahead of the defoliator to increase sugar percent and decrease loss to molasses to improve revenue per acre. This practice will reduce weeds in storage piles and decrease sugar loss as well.