Quick Intro

Physical Description

 

Species & Taxonomy

• Kingdom:
• Phylum:
• Class:
• Order:
• Family:
• Genus Species: Fusarium oxysporum f. sp.  callistephi

Plants Affected

 Aster family plants:

• aster
• daisy
• sunflower
• lettuce
• artichokes
• marigold
• chrysanthemums
• dahlias
• zinnias
• echinacea
• yarrow

Plants Unaffected

 

Geographical Range

 

Signs & Symptoms

Whole Plant

• rapid wilting of the plant, often followed by death
• stem base blackens and shrinks inward
• faint, furry, pale pink or white fungal growth may develop

Leaves

Flowers

Fruit

Roots/Tubers

How to Positively Identify

 

Treatment

• promptly remove and dispose of infected plants and the soil in the vicinity of the roots
• Fusarium can be killed with high heat, but most techniques of heating the soil don’t go deep enough into the soil
• try soil solarization

Prevention & Control

Treatment is very difficult, so controlling the spread of the fungus is important:

• promptly remove and dispose of infected plants and the soil in the vicinity of the roots
• Use a fresh site for future plantings of asters and plant only healthy-looking stock
• discard any with dead roots or damaged stem bases
• avoid planting asters on heavy soils, or improve soil texture before planting
• grow resistant cultivars