ISSUE 6 June 6, 2002
FROST, RAIN, AND WIND HIT SUGARBEET CROP
The sugarbeet crop in the Red River Valley was hit hard by adverse weather conditions. Frost, heavy rain, and high wind combined to damage struggling sugarbeet seedlings. American Crystal growers were hit hardest and have to replant about 14-15% (70,000-75,000 acres) of their crop. Min-Dak growers have to replant about 5% (5,000 acres), and Southern Minnesota growers about 2.5% (3,000 acres) of their acreage.
This is one of the worst years for the early stage of the sugarbeet crop in the United States. Some areas in Idaho were also severely affected by frost and had to replant about 55,000 acres. Growers in Wyoming also encountered problems in their planting operations. Let us hope we do not have any more disasters in this growing season.
RHIZOCTONIA AND APHANOMYCES OF SUGARBEET
Rhizoctonia causes seed rot, damping ff, or stunting of young plants. Rhizoctonia may kill plants in small areas in a field - sometimes a few acres, but rarely warrants replanting. This fungus infects seedlings when soil moisture range from somewhat dry to wet and prefer temperatures of 68-86E F.
Aphanomyces can be devastating in the seedling stage, and can also cause serious root rot later in the season. Infected plants turn a sickly yellow green and tend to wilt in the afternoons of hot and sunny days. Aphanomyces may infect a few plants to entire fields. Optimum conditions for infection occurs in wet soils at temperatures of 72-82E F.
Aphanomyces can be managed by using tolerant varieties; using Tachigaren pelleted seeds; planting early when possible; keeping the soil dry by enhanced drainage; effective weed control; and avoid spreading infected soil to disease free fields.
Extension Sugarbeet Specialist