Pacific Northwest Vegetable Extension Group

of Washington State University, Oregon State University, and University of Idaho

Photo Gallery of Vegetable Problems

Pea

General Pea Disease and Pest Management

(Click on photo to enlarge)

General Pea Disease and Pest Management

Pea Disease Diagnostic Series, North Dakota Agricultural Experiment Station

Diseases

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

Photo of aphanomyces root rot of pea Photo of aphanomyces root rot of pea
Aphanomyces root rot on pea roots of the cultivar Columbian (infection from inoculated peas grown in a greenhouse). Root lesions tend to be carmel-colored. Healthy peas on the left and infected peas on the right. 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).
 

Disease: Downy mildew
Pathogen: Peronospora viciae

Photo of Downy mildew on pea Photo of Downy mildew on pea Photo of external lesion on the pod Photo of infected pod showing internal signs of the pathogen.
External lesion on the pod. Infected pod showing internal signs of the pathogen.
Photo Source: G.Q. Pelter Photo Source: D.A. Inglis Photo Source: Lyndon Porter
Photo of Sporulating localized leaf lesions Photo of sporulating systemic leaf infection.
Sporulating localized leaf lesions. Sporulating systemic leaf infection.
Photo Source: Lyndon Porter

On-Line Resources:

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

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

Photo of Fusarium root rot of pea Photo of fusarium root rot of pea Photo of fusarium root rot of pea Photo of fusarium root rot of pea
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).
 

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.

Photo of fusarium wilt of pea Photo of fusarium wilt symptoms on pea Photo of fusarium wilt symptoms on pea Photo of fusarium wilt symptoms on pea
Reddish discoloration of the vascular tissue in pea roots rotted by the Fusarium wilt pathogen, Fusarium oxysporum f. sp. pisi. In addition to chlorosis of the lower leaves, symptoms of Fusarium wilt can include down-turned leaves. Plants with unilateral foliar chlorosis where, on the same stem, half of each leaf is chlorotic and the other half is green. 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: Lindsey du Toit

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).
 

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.

Photo of pea seedborne mosaic on pea pea-seedborne-mosaic-virus-2
   

Photo Source: Rebecca McGee

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

Disease: Powdery mildew
Pathogen: Erysiphe pisi

Photo of Powdery  mildew on pea
Photo Source: G.Q. Pelter

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

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

Photo of root rot complex symptoms on pea Photo of root rot complex symptoms on pea Photo of root rot complex symptoms on pea
Field symptoms of stunted plants caused by the root rot complex in a pea seed crop. 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: Lindsey du Toit

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
 

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

pea-thielaviopsis-root-rot-1 pea-thielaviopsis-root-rot-2 pea-thielaviopsis-root-rot-3 pea-thielaviopsis-root-rot-4 pea-thielaviopsis-root-rot-5
Whole pea plants with black roots from Thielaviopsis
root rot.

Photo Source: Lindsey du Toit

Photo Source: Lyndon Porter

Photo Source: Jordan Eggers

pea-thielaviopsis-root-rot-6 pea-thielaviopsis-root-rot-7

Photo Source: Jordan Eggers

On-Line Resources:

Thielaviopsis Root Rot of Pea, 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.
 

Nematodes

Disease: Pea cyst nematode
Pathogen: Heterodera goettingiana

Photo of Pea cyst nematode on pea Photo of Pea cyst nematode on pea Photo of Pea cyst nematode on pea-white cyst stage

Photo Source: D.A. Inglis

Photo Source: D.A. Inglis

(white cyst stage)
Photo Source: D.A. Inglis

On-Line Resources:

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

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

pea-root-lesion-nematode-1 pea-root-lesioin-nematode-2 pea-root-lesion-nematode-3 pea-root-lesion-nematode-4
Root lesion nematode from an infected pea root. Nematodes can cause circular patches of stunted pea plants. However, the patches are more commonly caused by Rhizoctonia. Infrared photo of a pea field infested with root lesion nematodes. Red areas indicate healthy plants. Light-colored areas indicate plants infested with nematodes. 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: Lindsey du Toit, WSU

Photo Source: Lyndon Porter, USDA ARS

Photo Source: O & T Images
 

Photo Source: Lyndon Porter, USDA ARS

On-Line Resources:

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

Insect/Mite Pests

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

Photo of pea moth larva in pea pod Photo of pea moth larva in pea pod Photo of pea moth larva on pea Photo of pea moth
    Pea moth larva
feeding on pea.
Adult pea moth reared
from the larva.
Photo Source: Arthur L. Antonelli, Washington State University Photo Source: Whatcom County, Washington State University Master Gardeners Photo Source: Charlie Streets, taken on July 9, 2010 on allotments at Halifax, West Yorkshire, UK. Photo Source: Charlie Streets, taken on April 26, 2011.

On-Line Resources:

Pea Moth, 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
 

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

Photo of pea weevil damage on pea Photo of pea weevil damage on pea seeds Phot of pea weevil damage on pea seeds photo of pea weevil and pea seeds
       
Photo Source: Lyndon Porter, USDA-ARS plant pathologist
Photo of pea weevils Microscopic photo of pea weevil
  Close-up image of a weevil through a microscope
Photo Source: Lyndon Porter, USDA-ARS plant pathologist 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


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.

Magnified image of a seedcorn maggot. Title
Magnified image of a 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

 

Abiotic Problems

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.

Photo of yellow-spotting on leaves due to application of a combination of basagran + metribuzin + In-Place Photo of severe yellow chlorotic areas on pea leaves several weeks after they were sprayed with a combination of basagran + metribuzin + In-place
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.
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, Identification & Management of Emerging Vegetable Problems in the Pacific Northwest. Pacific Northwest Vegetable Extension Group.


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.

Increasingly severe symptoms of edema on pods of the pea cv. Mrs. Van’s. Peas within the pods do not develop symptoms and are edible.
Increasingly severe symptoms of edema on pods of the pea cv. Mrs. Van’s. Peas within the pods do not develop symptoms and are edible.  
Photo Source: Joanne Henderson, Thunder Bay, Ontario, Canada

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

https://hort.uwex.edu/articles/edema/ University of Wisconsin Extension



 

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Contact Us: Lindsey du Toit and Carol Miles