AMSEED American Seed Intelligence Platform

Alternaria Stem Canker

Alternaria alternata f. sp. lycopersici · fungus

Issue type
disease
Seedborne
No
Resistance code
ASC
Affects
Tomato

Symptoms

Dark cankers girdle stems at soil line or wound sites with brown streaking in the pith; dark zonate lesions can mark fruit. Historically a California field problem.

Management

The Asc resistance gene (code ASC) shut this disease down in commercial production, a clean case of single-gene resistance solving a regional problem; it persists mainly where susceptible heirlooms are grown.

Varieties with documented resistance

VarietyLevelCodeDaysBreeding
Big Beef resistant ASC 70-73 F1 hybrid
Florida 91 resistant ASC 70-74 F1 hybrid
Patio resistant ASC 65-70 F1 hybrid
Red Deuce resistant ASC 70-75 F1 hybrid
Florida 47 resistant ASC 72-78 F1 hybrid

Sources & References

Evidence: 1 source, all independent references.

  1. Tomato Production and Cultivar Guides · University of Florida IFAS Extension, University or Government