Pepper bell Diseases A

Lecture To ToT trainees ( FFS) By

Mr. Allah Dad Khan Provincial Coordinator

IPM KPK MINFAL Pakistan

Bacterial spotXanthomonas campestris

Symptoms

• Water-soaked lesions that dry out and turn brown forming on the underside of the leaves; raised brown cankers on stems; cracked brown lesions on fruit

• Cause• Bacterium

Symptoms of bacterial spot on pepper leaf

Bacterial spotSymptoms of bacterial spot on pepper fruit

Symptoms of bacterial spot on pepper foliage

Bacterial spotSymptoms of bacterial spot on pepper foliage

Symptoms of bacterial spot on pepper foliage

Bacterial spotA shot hole appearance on a leaf infected with bacterial spot

Symptoms of bacterial spot on pepper foliage

Bacterial cankerClavibacter michiganensis

Symptoms

• Small, raised, white lesions on leaves that grow larger, turn brown and necrotic and may have a yellow halo; raised white lesions on fruit which coalesce to form larger spots, often with white halo

• Cause• Bacterium

Damping-offPythium spp.

Rhizoctonia solani

Symptoms

• Seeds did not germinate; seedlings collapsing and dying; dark stems which are shriveled near the soil line; water-soaked lesions on the stem; water-soaked discolored roots

• Cause• Fungi

Damping-off

Damping-off of pepper seedling Damping-off of pepper seedling

Powdery mildewLeveillula taurica

Symptoms

• Patches of white, powdery fungal growth on the underside of the leaves; yellow to brown discoloration of the upper leaf; edges of leaves may curl upwards exposing the underside of the leaf; leaves may begin dropping from plant

• Cause• Fungus

Pepper leaf infected with powdery mildew

powdery mildewPepper leaf infected with powdery mildew

Powdery mildew symptoms on pepper leaf

Fusarium wiltFusarium oxysporum most

Symptoms

• Yellowing of foliage and wilting upper leaves; wilting spread to all parts of plant; leaves remain attached to plant and are dark green in color; red-brown discoloration of vascular tissue; plant death

• Cause• Fungus

Phytophthora blightPhytophthora caspsici

Symptoms

• Black lesions on stems; wilting plant; circular gray-brown lesions on leaves; dark lesions on fruit which may be covered in white sporangia

• Cause• Oomycete

Phytophthora blight symptoms on pepper fruit

Phytophthora blightPepper plant infected with Phytophthora blight

Symptoms of the disease includes wilting of the plant. However, other diseases can also cause this symptom and the plants needs to be carefully analyzed for confirmation

Phytophthora blight

Field infestation of Phytophthora blightThe pathogen can easily spread through rain splash or running water and wind.

Phytophthora blightA characteristic symptom is the crown rot and black lesion at the crown region which is indicative of the disease. Such symptoms develop especially during high rainfall conditions or in areas with water logging or excessive moisture.

Pepper plants infected with Phytophthora blight

Southern blightSclerotium rolfsii

Symptoms

• Sudden wilting of leaves; yellowing foliage; browning stem above and below soil; browning branches; stem may be covered with fan-like mycelial mat

• Cause• Fungus

Stem lesions on pepper caused by Southern blight

Pepper plant infected with Southern blight

Southern blight grows best in warm, humid conditions. The first symptom is the wilting of the the plant to wilt. At the collar region of the stem you will

notice a brown blighted section

The fungus can often be seen growing as a white mycelial mat growing on the stem and the surrounding soil. The mycelia will develop sclerotia which are light tan to dark

brown pathogen survives in the soil or in plant debris, volunteers and weeds

Discolored pepper stem

As the disease progresses the plant will continue to wilt and leaves will eventually turn brown. Because the canopy is being destroyed fruit will become more susceptible to sunscald and secondary

pathogens.

MosaicCucumber mosaic virus (CMV)

Potato virus Y (PVY) Symptoms

• Alternating light and green areas or mosaic patterns on the leaves; leaves distorted and curled; slow plant growth

• Cause• Virus

Blossom-end rot

Symptoms

• Small water-soaked area on end of fruit where the blossom was occurring or on the side of unripe fruit; lesion enlarges and turns sunken, tan brown and leathery in appearance

• Cause• Low calcium concentration

in fruit

Blossom-end rot on pepper fruit

Blossom-end rot

Blossom-end rot on pepper fruit As the fruit grows the spot will also enlarge and may eventually cover up to half of the fruit. Fungi and bacteria may attack the damaged tissue causing tissue discoloration

Blossom End Rot

• Anything that reduces the plants ability to uptake calcium can lead to the development of this disorder, with one of the main reasons being the availability of water. Symptoms begin as a small, water soaked light brown spot at the blossom end of the fruit

Tomato spotted wilt virusTomato spotted wilt virus (TSWV)

Symptoms

• Symptoms may vary widely depending on variety and environmental conditions; generally leaves become spotted and bronzed in appearance; plant may droop or wilt; fruit develop concentric rings which are light in color and become necrotic

• Cause• Virus

Characteristic ring spots on pepper fruit

Tomato spotted wilt virusSymptoms

• Symptoms may vary widely depending on variety and environmental conditions; generally leaves become spotted and bronzed in appearance; plant may droop or wilt; fruit develop concentric rings which are light in color and become necrotic

• Cause• Virus

Necorsis of pepper fruit caused by TSWV

Tomato spotted wilt virusTSWV is transmitted by thrips, which can only acquire the virus as larvae and transmits it as an adult. The initial symptom is chlorosis on leaves

In addition to chlorosis leaves may also become twisted and distorted. The severity and appearance of symptoms will vary depending on the cultivar, the age of the plant at the time of infection, environmental conditions and the virus isolate

Tomato spotted wilt virusFruit may also be affected, developing chlorotic or necrotic spots, ring spots or mosaics.

Tomato spotted wilt virus

Pepper plant infected with TSWVLeaves of infected plants may also develop chlorotic or necrotic ring spots