Botrytis Rot Symptoms on Artichokes

Botrytis Rot, (also known as Gray Mold or Bud Rot), on artichokes is caused by the fungal pathogen Botrytis cinerea, a common and widespread pathogen with a variety of hosts. It can infect artichoke leaves or fruit bracts. This pathogen typically enters plant tissues that have been damaged or wounded by mechanical injury, frost damage, snails, slugs or other insects.

Infected areas typically turn brown and soft on the outside, with gray mold spores visible on the inner surfaces of the bracts.

This fungus survives on decaying organic matter, or on older, senescent leaves. It is spread by wind, and can have a wide variety of host crops, making it a prevalent disease in most areas where artichokes are grown.

Conditions for Infection

The optimum conditions for growth and development of Botrytis cinerea are cool and wet conditions. Prolonged wetness periods are usually needed for infection to occur. The Pest Prophet app can help to monitor weather conditions to assess risk for Botrytis cinerea infection, based on localized weather data. This can be helpful in determining risk of Botrytis cinerea infections and may be used to optimize timing of preventative fungicide sprays.

Post-harvest storage conditions can also affect severity of disease symptoms on Artichokes. Moderate temperatures and higher humidity storage conditions are optimum for growth of this disease on infected Artichoke buds.

Disease Management

The best way to avoid botrytis infections in artichokes are to reduce the amount of possible entry points for the fungus by avoiding any mechanical injuries, reducing frost damage and controlling insect pests which may damage leaf or fruit bracts. Planting and row orientation should be planned in a way that maximizes air movement, which can decrease leaf wetness, and also improve spray coverage. Dead plants, organic matter and debris piles should be removed from field and infected plants should be culled and removed as well to reduce sources of inoculum.

Fungicides should be applied to prevent infection, as they will be less effective after infection has occurred. Preventative fungicides may not be necessary in a given season, depending on field history and weather (temperature/ leaf wetness). The Pest Prophet app can be used to determine how conducive weather conditions in a field are for botrytis growth and reproduction.

Post-harvest, artichoke buds should be stored in dry areas. Applying fungicides before harvest may help spread of this disease post harvest.

Learn More: Complete Guide to Botrytis (Gray Mold)

Sources:

Botrytis Rot of the Globe Artichoke. Link et al. Journal of Agricultural Research. 1924.