Chile

DISEASE MANAGEMENT: Wet Rot, Choanephora blight

Choanephora cucurbitarum
SIGNS & SYMPTOMS:
• • • • • Water soaked lesions appear on the leaves and the margins and leaf tips are blighted. Olderlesions turn necrotic and appear dried out. The entire plant may wilt. Flowers and flower buds turn dark and wilt. Young fruit can be infected.

DISEASE CYCLE & EPIDEMIOLOGY:
• • • This disease isnot common on pepper plants in Florida. The fungus has a wide host range such as yellow squash and some common weeds. Outbreaks of this disease occur during extended rainy periods and hightemperatures.

FIELD SIGNATURE:
• ‘Whiskers’ of the fungus, which are fungal strands, with dark-colored, knobby sporangiola, can be seen with a hand lens. Morning is the best time to look for the fungus.Symptoms may be confused with Phytophthora blight (Phytophthora capsici).

• •

PHOTOS:
Figure 1. Silvery whiskers grow out of infected areas, topped with black spore masses. Courtesy of: AVRDC.Figure 2. Most of the time, it seems to start in senescing flower petals. Once established, entire flowers are overgrown, resulting in a brown to black mass of soft tissue. Flower stalks, buds, and leavesmay subsequently be invaded. Photograph by: UF/IFAS. Figure 3. Close-up of sporulating fungus on leaf surface. Photograph by: UF/IFAS.

Prepared by: Dr. Pam Roberts

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DISEASE MANAGEMENT:Wet Rot, Choanephora blight CULTURAL CONTROLS:
• Any method which increases air movement in the crop canopy to reduce the humidity may aid in management. Examples include: o o o o Increase plantspacing Adequate drainage Avoid overhead irrigation Avoid excess nutrition which creates a dense canopy

CHEMICAL CONTROL:
• There are no fungicides labeled for this disease. Sprays for other fungaldiseases may reduce disease damage.

RESISTANT CULTIVARS:
• There are no resistant cultivars for tomatoes or peppers.

CONTACT INFORMATION:
Dr. Pamela D. Roberts UF/IFAS SWFREC 2686 SR 29 N...