Albugo

Albugo
Albugo candida, on Capsella bursa-pastoris
Scientific classification
Phylum:	Heterokontophyta
Class:	Oomycota
Order:	Peronosporales
Family:	Albuginaceae
Genus:	Albugo
Species
Many, see text

Many, see text

Albugo is a genus of plant-parasitic oomycetes. Those are not true fungi (Eumycota), although many discussions of this organism still treat it as a fungus. The taxonomy of this genus is incomplete, but several species are plant pathogens. Albugo is one of three genera currently described in the family Albuginaceae, the taxonomy of many species is still in flux.

This organism causes white rust or white blister diseases in above-ground plant tissues. While these organisms affect many types of plants, the destructive aspect of infection is limited to a few agricultural crops, including: beets (garden and sugar), Brussels sprouts, cabbages, Chinese cabbage, cauliflower, collards, garden cress, kale, lettuce, mustards, parsnip, radish, horseradish, rape, salsify (black or white), spinach, sweet potatoes, turnips, watercress, and perhaps water-spinach.

White rust plant diseases caused by Albugo fungal-like pathogens should not be confused with White Pine Blister Rust, Chrysanthemum white rust or any fungal rusts, all of which are also plant diseases but have completely different symptoms and causal pathogens. Symptoms of white rust caused by Albugo typically include yellow lesions on the upper leaf surface and white pustules on the underside of the leaf. The pathogen is spread by wind, water, and insects. Management includes use of resistant cultivars, proper irrigation practices, crop rotation, sanitation, and chemical control. White rust is an important economic disease, causing severe crop losses if not controlled.

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Wikipedia