July 25, 2025

Diagnosing important diseases in Pepper – Reference Guide

Phytophthora blight causing plants to wilt and die Phytophthora blight – crown rot Phytophthora crown rot. Note the blackish-brown necrotic tissue at base of the stem
Phytophthora sporulating on infected bell pepper fruit. Phytophthora fruit rot (L) and Pythium blight (R) Symptoms of Phytophthora blight on infected leaves. Under ideal conditions leaf infections can occur.
Anthracnose fruit rot Anthracnose fruit rot. Note the salmon colored spores being produced in the lesion of the lesion. Sunscald on pepper fruit (L) and Anthracnose fruit rot (R)
Bacterial leaf spot on leaves Bacterial leaf spot. Note the infected leaves falling off of plant. Bacterial leaf spot infection of pepper fruit. Note the irregular raised scabby spots on fruit.
Southern blight on infected stem. Note the numerous small fruiting bodies (sclerotia) developing on the stem White mold infecting pepper stem. Infected stems come brittle and hollow White mold sclerotia present on inside of infected stem
Blossom end rot Cucumber Mosaic Virus Cyclamen mite feeding injury. Symptoms resemble virus infection
Others:
Mefenoxam injury on a young pepper transplant Sunscald on stems of pepper recently transplanted into black plastic mulch. Cyclamen mite damage on immature pepper fruit
“Silvering” on mature bell pepper fruit. “Silvering” on the right and thrips feeding injury on the Left Edema on pepper fruit

Andy Wyenandt, Wesley Kline, and Kris Holmstrom

Filed Under: Vegetable Crops Tagged With:
July 14, 2023

Diagnosing important diseases in Pepper – Reference Guide

Phytophthora blight causing plants to wilt and die Phytophthora blight – crown rot Phytophthora crown rot. Note the blackish-brown necrotic tissue at base of the stem
Phytophthora sporulating on infected bell pepper fruit. Phytophthora fruit rot (L) and Pythium blight (R) Symptoms of Phytophthora blight on infected leaves. Under ideal conditions leaf infections can occur.
Anthracnose fruit rot Anthracnose fruit rot. Note the salmon colored spores being produced in the lesion of the lesion. Sunscald on pepper fruit (L) and Anthracnose fruit rot (R)
Bacterial leaf spot on leaves Bacterial leaf spot. Note the infected leaves falling off of plant. Bacterial leaf spot infection of pepper fruit. Note the irregular raised scabby spots on fruit.
Southern blight on infected stem. Note the numerous small fruiting bodies (sclerotia) developing on the stem White mold infecting pepper stem. Infected stems come brittle and hollow White mold sclerotia present on inside of infected stem
Blossom end rot Cucumber Mosaic Virus Cyclamen mite feeding injury. Symptoms resemble virus infection
Others:
Mefenoxam injury on a young pepper transplant Sunscald on stems of pepper recently transplanted into black plastic mulch. Cyclamen mite damage on immature pepper fruit
“Silvering” on mature bell pepper fruit. “Silvering” on the right and thrips feeding injury on the Left Edema on pepper fruit

The following images consist of important diseases in pepper. These images can be used as a quick reference for diagnosing important fungal and bacterial pathogens. For best results, please turn your device (i.e., cell phone) sideways. For information on commercial control recommendations, please visit the pepper section of the 2022/2023 Mid-Atlantic Commercial Vegetable Production Guide.

Andy Wyenandt, Wesley Kline, and Kris Holmstrom

Filed Under: Vegetable Crops Tagged With:
July 14, 2022

Diagnosing important diseases in Pepper – Reference Guide

Phytophthora blight causing plants to wilt and die Phytophthora blight – crown rot Phytophthora crown rot. Note the blackish-brown necrotic tissue at base of the stem
Phytophthora sporulating on infected bell pepper fruit. Phytophthora fruit rot (L) and Pythium blight (R) Symptoms of Phytophthora blight on infected leaves. Under ideal conditions leaf infections can occur.
Anthracnose fruit rot Anthracnose fruit rot. Note the salmon colored spores being produced in the lesion of the lesion. Sunscald on pepper fruit (L) and Anthracnose fruit rot (R)
Bacterial leaf spot on leaves Bacterial leaf spot. Note the infected leaves falling off of plant. Bacterial leaf spot infection of pepper fruit. Note the irregular raised scabby spots on fruit.
Southern blight on infected stem. Note the numerous small fruiting bodies (sclerotia) developing on the stem White mold infecting pepper stem. Infected stems come brittle and hollow White mold sclerotia present on inside of infected stem
Blossom end rot Cucumber Mosaic Virus Cyclamen mite feeding injury. Symptoms resemble virus infection
Others:
Mefenoxam injury on a young pepper transplant Sunscald on stems of pepper recently transplanted into black plastic mulch. Cyclamen mite damage on immature pepper fruit
“Silvering” on mature bell pepper fruit. “Silvering” on the right and thrips feeding injury on the Left Edema on pepper fruit

Andy Wyenandt, Wesley Kline, and Kris Holmstrom

Filed Under: Vegetable Crops Tagged With: