Photo Gallery of Vegetable Problems Swiss – Chard | Mount Vernon NW Washington Research & Extension Center

Diseases
Ramularia leaf spot	Rhizoctonia basal petiole and crown infection
Insect/Mite Pests
Aphids Lygus bugs	Springtails

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Diseases

Disease: Ramularia leaf spot
Pathogen: Ramularia beticola
Host crops: Most vegetables in the Chenopodiaceae, i.e., sugar beet, table beet, and Swiss chard.

		Typical large, necrotic leaf spots caused by Ramularia beticola on a leaf sampled from a Swiss chard seed crop. Discrete, circular, necrotic lesions of Ramularia leaf spot on a leaf sampled from a Swiss chard seed crop. Two-celled, hyaline spores of Ramularia beticola from an infected Swiss chard leaf.
Ramularia leaf spot on Swiss chard leaves.
Photo Source: D.A. Inglis, Washington State University		Photo Source: Lindsey du Toit, Washington State University

Online Resources:

Pacific Northwest Plant Disease Management Handbook: Sugar Beet (Beta vulgaris) – Ramularia Leaf Spot

Disease: Rhizoctonia basal petiole and crown infection
Pathogens:Rhizoctonia
Host crops: Many vegetables are susceptible to infection by Rhizoctonia spp., which are common soilborne fungi. In beet and Swiss chard, these fungi can infect the base of petioles and the crown or main root at or below the soil surface, particularly in moist soil conditions. During very wet conditions, infection can also occur on the leaves.

Lesion at the base of a Swiss chard petiole caused by Rhizoctonia. Severe root, crown, and petiole infection by Rhizoctonia on a Swiss chard plant. Swiss chard foliar lesions caused by Rhizoctonia. Severe root and crown symptoms caused by infection of plants in a Swiss chard seed crop by Rhizoctonia.
Photo Source: Lindsey du Toit, Washington State University

Online Resources:

Pacific Northwest Plant Disease Management Handbook

Insect/Mite Pests

Common name: Aphids (various types)
Latin binomial: Aphis fabae (bean aphid), Myzus persicae (green peach aphid)
Host crops: Table beet, sugar beet, Swiss chard, and various other vegetable and weed plant species

Aphids in a Swiss chard seed crop. Note the blackened stems and leaves as a result of sooty mold fungi growing on the honeydew exudate (sugary, sticky exudate) produced by the aphids.

Close-up image of aphids on a Swiss chard plant in a seed crop. Note the blackened stems and leaves as a result of sooty mold fungi growing on the honeydew exudate (sugary, sticky exudate) produced by the aphids, as well as the shriveled white cast ‘skins’ produced by aphids as they moult.

Photo Source: Lindsey du Toit, Washington State University

Online Resources:

http://insect.pnwhandbooks.org/vegetable/vegetable-pests/hosts-and-pests/chard-swiss-aphid

Common Name: Lygus bugs
Latin binomial: Lygus spp.
Host crops: Numerous different species of vegetables and other crops, e.g., alfalfa, beet, cabbage, carrot, spinach, Swiss chard, etc. Lygus bugs can cause different types of damage to various growth stages of different crops. They cause blackheart on celery, blasting on flower tissues, collapse of asparagus spears, decreased yields in carrot, beet, spinach, and other seed crops, etc.

Black streaks on the main stem, and black discoloration and dieback of the buds at the tip of a flowering plant from a Swiss chard seed crop in western Washington, resulting from feeding injury caused by lygus bugs. Dark lesions on the midrib, and necrosis/dieback of the tip of a leaf from a Swiss chard seed crop as a result of injury caused by lygus bugs. An early nymphal instar of a lygus bug on a Swiss chard plant in a seed crop. A lygus bug nymph feeding on the flowers of a Swiss chard plant in a seed crop in western Washington. A lygus bug on a Swiss chard plant. Note the wing pads developing on the insect.
Photo Source: Bev Gerdeman, WSU Entomologist

Online Resources:

Pacific Northwest Insect Management Handbook: Vegetable crop pests – Lygus bug

Common Name: Springtails (subterranean types)
Latin binomial: Order Collembola. There are numerous types of springtails or collembola, which are divided into two groups – subterranean springtails and surface springtails.
Host crops: Multiple vegetables, but most damage has been reported on spinach and beets, primarily in heavier, organic soils during very wet, cool spring conditions.


A subterranean springtail extracted from soil in a spinach seed crop.
Photo Source: Lindsey du Toit, Washington State University

Online Resources:

Springtails Springtails in Sugarbeet: Identification, Biology, and Management. North Dakota State University, Fargo

Control of Subterranean Springtails in Sugarbeet Using Granular, Liquid, and Seed Treatment Insecticides. North Dakota State University, Fargo

Springtail feeding on emerging crops (especially sugarbeet). Michigan State University

Pest: Springtail. Pest Spotter, Bayer CropScience