AMSEED American Seed Intelligence Platform

Bacterial Speck

Pseudomonas syringae pv. tomato · bacteria

Issue type
disease
Seedborne
Yes, travels on seed
Resistance code
Pst
Affects
Tomato

Symptoms

Tiny dark specks with yellow halos on leaves and pinpoint raised black specks on green fruit that persist to harvest. Favors cool wet spring weather, then stalls in heat.

Management

The Pto resistance gene (code Pst) in many hybrids controls race 0 outright. Otherwise: clean seed, rotation, and copper early, the disease is cosmetic on fruit but defoliating in bad springs.

Varieties with documented resistance

No commercial varieties in the database carry documented resistance to this issue, management is cultural and (for seedborne pathogens) starts with tested, certified seed.

Sources & References

Evidence: 1 source, all independent references.

  1. Vegetable MD Online · Cornell University, Plant Pathology, University or Government