Extension Network Sites > Pacific Northwest Vegetable Extension Group > Photo Gallery of Vegetable Problems > Pea

Pea

General Pea Disease and Pest Management

Diseases

Nematodes

Insect/Mite Pests

Abiotic Problems

Diseases

Aphanomyces root rot
Downy mildew
Fusarium root rot

Fusarium wilt
Pea seedborne mosaic
Powdery mildew

Root rot complex
Thielaviopsis root rot

Nematodes

Pea cyst nematode

Root lesion nematode

Insect/Mite Pests

Pea moth

Pea weevil

Seedcorn maggot

Abiotic Problems

Adjuvant damage

Edema

(Click on photo to enlarge)

General Pea Disease and Pest Management

Pea Disease Diagnostic Series (pdf), North Dakota Agricultural Experiment Station.

Diseases

Aphanomyces root rot

Disease: Aphanomyces root rot
Pathogen: Aphanomyces euteiches
Host Crop: Pea

aphanomyces root rot of pea-2 — Close-up of roots infected with Aphanomyces euteiches, showing the typical carmel color of infected roots.
**Photo Source:** Lyndon Porter

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Aphanomyces Root Rot.
Pea Disease Diagnostic Series – Aphanomyces root rot, North Dakota Agricultural Experiment Station.
See also: Root rot complex caused by mixed infections of Fusarium wilt (FW), Aphanomyces root rot (ARR) and Fusarium root rot (FRR).

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Downy mildew

Disease: Downy mildew
Pathogen: Peronospora viciae

Downy mildew symptoms -3 — Sporulating localized leaf lesions.
**Photo Source:** Lyndon Porter

Downy mildew on pea-2 — **Photo Source:** D.A. Inglis

Downy mildew symptoms on leaves-4 — Sporulating systemic leaf infection.
**Photo Source:** Lyndon Porter

Downy mildew symptoms on pea pods-1 — External lesion on the pod.
**Photo Source:** Lyndon Porter

Downy mildew symptoms in pea pods-2 — Infected pod showing internal signs of the pathogen.
**Photo Source:** Lyndon Porter

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Downy Mildew.

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Fusarium root rot

Disease: Fusarium root rot
Pathogen: Fusarium solani f. sp. pisi

Fusarium root rot of pea-2 — Fusarium root rot on pea roots (infection from inoculated peas grown in a greenhouse). Root lesions tend to be dark black in color.
**Photo Source:** Lyndon Porter

Fusarium root rot of pea-3 — Fusarium root rot on pea roots (infection from inoculated peas grown in a greenhouse). Root lesions tend to be dark black in color.
**Photo Source:** Lyndon Porter

Fusarium root rot of pea-4 — Fusarium root rot on pea roots (infection from inoculated peas grown in a greenhouse). Root lesions tend to be dark black in color.
**Photo Source:** Lyndon Porter

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Root Rots.
Pea Disease Diagnostic Series – Fusarium root rot, North Dakota Agricultural Experiment Station.
See also: Root rot complex caused by mixed infections of Fusarium wilt (FW), Aphanomyces root rot (ARR) and Fusarium root rot (FRR).

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Fusarium wilt

Disease: Fusarium wilt
Pathogen: Fusarium oxysporum f. sp. pisi. Races 1, 5, and 6 of the fungus cause true wilt symptoms; race 2 isolates produce near-wilt symptoms. Races 5 and 6 are economically important in western Washington and southwest British Columbia. Races 1 and 2 reportedly are in all pea-growing regions of Oregon and Washington.

fusarium wilt symptoms on pea-1 — In addition to chlorosis of the lower leaves, symptoms of Fusarium wilt can include down-turned leaves.

fusarium wilt symptoms on pea-2 — Plants with unilateral foliar chlorosis where, on the same stem, half of each leaf is chlorotic and the other half is green.
**Photo Source:** Lyndon Porter

fusarium wilt symptoms on pea-3 — Yellow, red, orange or rustic discoloration of the vascular tissue in pea plants infected with Fusarium wilt. Each stem was cut lengthwise to show the vascular discoloration.
**Photo Source:** Lyndon Porter

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Wilt and Near-wilt.
Pea Disease Diagnostic Series – Fusarium wilt, North Dakota Agricultural Experiment Station.
See also: Root rot complex caused by mixed infections of Fusarium wilt (FW), Aphanomyces root rot (ARR) and Fusarium root rot (FRR).

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Pea seedborne mosaic

Disease: Pea seedborne mosaic
Pathogen: Pea seedborne mosaic virus (PSbMV)
Host Crops: Pea and at least 46 other plant species in 12 families, of which only a few are economically important hosts, including lentil, vetch, chickpea, and pea.

pea seedborne mosaic virus-1 — **Photo Source:** Lyndon Porter, USDA-ARS

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Pea Seedborne Mosaic.
Pea Disease Diagnostic Series – Pea seedborne mosaic virus, North Dakota Agricultural Experiment Station.

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Powdery mildew

Disease: Powdery mildew
Pathogen: Erysiphe pisi

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Powdery Mildew.
Pea: Powdery mildew, Washington State University Hortsense.
Pea Disease Diagnostic Series – Powdery mildew, North Dakota Agricultural Experiment Station.

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Root rot complex

Disease: Root rot complex caused by mixed infections of Fusarium wilt (FW), Aphanomyces root rot (ARR) and Fusarium root rot (FRR).
Pathogen: Fusarium oxysporum f. sp. pisi (FW), Aphanomyces euteiches (ARR), and Fusarium solani f. sp. pisi (FRR).
Host Crop: Pea

root rot complex symptoms on pea-2 — Chlorosis, leading to necrosis, of the lower leaves of pea plants infected with the root rot complex that consists of the pathogens that cause Aphanomyces root rot, Fusarium wilt, and Fusarium root rot. All three diseases alone will cause leaf chlorosis that begins with the lowest leaves on the plant and moves towards the top of the plant. Chlorotic leaves will turn necrotic as the plant matures. Chlorosis of leaves from the bottom of the plant to the top of the plant is most pronounced when Fusarium wilt is involved. Severe infection by Fusarium root rot will stunt the plant but, in general, will not kill the plant. Severe infections by Fusarium wilt or Aphanomyces root rot will generally kill the plants.
**Photo Source:** Lyndon Porter

root rot complex symptoms on pea-3 — Chlorosis, leading to necrosis, of the lower leaves of pea plants infected with the root rot complex that consists of the pathogens that cause Aphanomyces root rot, Fusarium wilt, and Fusarium root rot. All three diseases alone will cause leaf chlorosis that begins with the lowest leaves on the plant and moves towards the top of the plant. Chlorotic leaves will turn necrotic as the plant matures. Chlorosis of leaves from the bottom of the plant to the top of the plant is most pronounced when Fusarium wilt is involved. Severe infection by Fusarium root rot will stunt the plant but, in general, will not kill the plant. Severe infections by Fusarium wilt or Aphanomyces root rot will generally kill the plants.
**Photo Source:** Lyndon Porter

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Root Rots.
Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Aphanomyces Root Rot.
Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Wilt and Near-wilt.
Pea Disease Diagnostic Series – Fusarium root rot, North Dakota Agricultural Experiment Station.

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Thielaviopsis root rot

Disease: Thielaviopsis root rot
Pathogen: Thielaviopsis basicola
Host Crops: Alfalfa, bean, carrot, corn, pea, pepper and many other plant species.

pea-thielaviopsis-root-rot-2 — **Photo Source:** Lyndon Porter

pea-thielaviopsis-root-rot-3 — **Photo Source:** Lyndon Porter

pea-thielaviopsis-root-rot-4 — **Photo Source:** Jordan Eggers

pea-thielaviopsis-root-rot-6 — **Photo Source:** Jordan Eggers

pea-thielaviopsis-root-rot-7 — **Photo Source:** Jordan Eggers

On-Line Resources:

Thielaviopsis Root Rot of Pea (pdf), Identification & Management of Emerging Vegetable Problems in the Pacific Northwest. Pacific Northwest Vegetable Extension Group.
Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Root Rots.
Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Seed Rot and Damping-off.
Emerging and Common Disease Issues in Peas, USDA-ARS.
Root Rots of Pea, University of Illinois Extension.

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Nematodes

Pea cyst nematode

Disease: Pea cyst nematode
Pathogen: Heterodera goettingiana

Pea cyst nematode on pea-2 — **Photo Source:** D.A. Inglis

Pea cyst nematode on pea-white cyst stage — (white cyst stage)
**Photo Source:** D.A. Inglis

On-Line Resources:

Pacific Northwest Plant Disease Management Handbook: Pea (Pisum sativum) – Nematode, Cyst.

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Root lesion nematode

Common name: Root lesion nematode
Latin binomial: Pratylenchus penetrans
Host Crops: Pea and many vegetables/other plant species

pea-root-lesion-nematode-2 — Nematodes can cause circular patches of stunted pea plants. However, the patches are more commonly caused by Rhizoctonia.
**Photo Source:** Lyndon Porter, USDA ARS

pea-root-lesion-nematode-3 — Infrared photo of a pea field infested with root lesion nematodes. Red areas indicate healthy plants. Light-colored areas indicate plants infested with nematodes.
**Photo Source:** O & T Images

pea-root-lesion-nematode-4 — Pea roots infested with root lesion nematodes. Plants have few secondary roots. With development of adventitious roots above the seed piece, plants may survive.
**Photo Source:** Lyndon Porter, USDA ARS

On-Line Resources:

Root Lesion Nematodes on Pea (pdf), Identification & Management of Emerging Vegetable Problems in the Pacific Northwest, Pacific Northwest Vegetable Extension Group.

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Insect/Mite Pests

Pea moth

Common name: Pea moth
Latin binomial: Cydia nigricana
Host crops: Pea, sweet pea, and vetch

pea moth larva in pea pod-2 — **Photo Source:** Whatcom County, Washington State University Master Gardeners

pea moth larva in pea pod-1 — Pea moth larva feeding on pea.
Photo Source: Charlie Streets, taken on July 9, 2010 on allotments at Halifax, West Yorkshire, UK.

adult pea moth on a leaf — Adult pea moth reared from the larva.
**Photo Source:** Charlie Streets, taken on April 26, 2011.

On-Line Resources:

Pea Moth (pdf), WSU PLS-59, Washington State University.
Pea moth, Pest Spotter, Bayer CropScience.
Pea moth, Royal Horticultural Society.
Pacific Northwest Insect Management Handbook: Pea, green and dry-Pea moth.

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Pea weevil

Common name: Pea weevil
Latin binomial: Bruchus pisorum
Host crops: Pea (Pisum spp.)

pea weevil damage on pea seeds-1 — **Photo Source:** Lyndon Porter, USDA-ARS plant pathologist

pea weevil damage on pea seeds-2 — **Photo Source:** Lyndon Porter, USDA-ARS plant pathologist

pea weevil damage on pea seeds-3 — **Photo Source:** Lyndon Porter, USDA-ARS plant pathologist

pea weevils-1 — **Photo Source:** Lyndon Porter, USDA-ARS plant pathologist

pea weevil-2 — Close-up image of a weevil through a microscope.
**Photo Source:** Tim Waters, WSU Extension Educator for Benton/Franklin Counties

On-Line Resources:

Pacific Northwest Insect Management Handbook: Pea, green and dry-Pea weevil.
Pea Weevil: Bruchus pisorum (Linnaeus) (Coleoptera: Chrysomelidae), SARDI, Pests and Diseases.
Pea Weevil: Bruchus pisorum (Linnaeus), Canadian Grain Commission.

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Seedcorn maggot

Common name: Seedcorn maggot
Latin binomial: Delia platura
Host crops: Many vegetable crops including snap, kidney, and lima beans, onion, corn, turnip, pea, cabbage, and cucurbits. They cause the most damage in spring to newly emerging seedlings, and can cause severe losses in plant stand.

damaged pea seedlingd by seedcorn-maggot — Damage to pea seedlings caused by the seedcorn maggot.
**Photo Source:** Lindsey du Toit, Washington State University

Online Resources:

Seedcorn maggot, Vegetable Crop Pests, Pacific Northwest Insect Management Handbook.
Seedcorn Maggot, University of California IPM Pest Management Guidelines, Corn.
Seed Corn Maggot, VegEdge, Vegetable IPM Resource for the Midwest, University of Minnesota.
Hosts and Pests of Vegetable Crops, Pacific Northwest Insect Management Handbook.

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Abiotic Problems

Adjuvant damage

Disease: Adjuvant Damage
Causal Organism/Agent: “In-Place” is a deposition aid and drift management agent added as a tank mix with pesticides to reduce spray drift during applications. The active ingredients of In-Place are modified vegetable oil, aliphatic mineral oil, amine salts of organic acids, and aromatic acid.
Host Crops: Pea.

yellow spotting on pea leaves-1 — Yellow-spotting on leaves due to application of a combination of basagran + metribuzin + In-Place. In-Place is a deposition aid that is added to a tank mix with pea herbicide to prevent/ reduce drift. In-Place tends to concentrate the herbicides at certain locations on the leave surface, resulting in yellow spots on the foliage.
**Photo Source:** Lyndon Porter, USDA ARS

yellow-spotting on pea leaves-2 — Severe yellow chlorotic areas on pea leaves several weeks after they were sprayed with a combination of basagran + metribuzin + In-place.
**Photo Source:** Lyndon Porter, USDA ARS

On-Line Resources:

Adjuvant Damage on Pea (pdf), Identification & Management of Emerging Vegetable Problems in the Pacific Northwest. Pacific Northwest Vegetable Extension Group

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Edema

Problem: Edema
A physiological problem most prominent when air is cooler than the soil, soil moisture is high, and relative humidity is high. The low plant transpiration rate combined with an increase in water absorption by roots from the soil leads to increased cell turgor pressure, resulting in eruption of epidermal cells as the inner cells enlarge. Protrusion of the inner cells causes epidermal cells to die and discolor, resulting in a ’warty’ appearance that can be misidentified as a disease. Symptoms are usually worse on lower leaf vs. upper leaf surfaces. Some pea cultivars are more prone to this condition than others.
Host crops: Numerous vegetables including brassicas, cucurbits, pea, spinach, tomato, etc.

Online Resources:

What are these bumps on my vegetables? Edema or oedema: It doesn’t matter how you spell it, it still doesn’t look good. What is it, what causes it and how can I prevent it? Michigan State University Extension.
University of Wisconsin Extension.

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