Physoderma maydis is a species of fungus in the family Physodermataceae. It is a pathogen of the maize, causing a disease known as brownspotof maize or brownspotofcorn. Physodermabrownspot is caused by the pathogen Physoderma maydis, the only class of fungi that produce zoospores, spores that have a tail (flagellum) and sw... Unlike PhysodermaBrownSpot, PSR isn’t as easy to spot. That is, until you hear it: the unmistakable “snap” of a breaking corn stalk. Usually attacking the V6 or V7 node, the disease creates a black ring around the lower node, which destabilizes the plant... Physodermabrownspot is caused by the chytridiomycete fungus, Physoderma maydis (syn. P. zeae-maydis), which is closely related to the oomycete or water mold fungi, such as the downy mildews. This disease is normally an infrequent, minor disease in corn that we observe... PhysodermaBrownSpotOfCorn – Treating Corn With BrownSpot Disease. Mary Ellen Ellis's avatar.The characteristic symptoms ofcornbrownspot infection are the formation of small, round or oval lesions that may be yellow, brown, or even a brownish purple in color. Physodermabrownspot can be a striking foliar disease that is periodically observed in field corn in Kentucky. This publication describes the symptoms and cause of disease, conditions that favor disease development, and options for disease management. Physodermabrownspot is a minor disease found in most areas where corn is grown and the leaf blight phase of the disease rarely affects yield. Many growers experience PhysodermaBrownSpot in their corn crops each year.Disease Control. PhysodermaBrownSpot rarely has any yield impact. Extreme cases can cause stalk integrity issues. Infection near nodes 6 and 7 can cause the stalk to break easily. Physoderma maydis—BrownSpot and Stalk Rot ofCorn. Physodermabrownspot is not usually considered an economically important disease in the Midwest, but occurrence of the disease has. increased over the last decade. Physoderma, caused by the fungus Physoderma maydis, is a significant disease affecting corn and other crops in the United States and Canada.The most notable symptom is the presence of dark, oval to circular spots, often referred to as "brownspot" or "Physodermabrownspot." Physoderma stalk rot (PSR) is caused by Physoderma maydis, which also causes Physodermabrownspot (PBS) in corn. Physoderma can cause stalk rot and reduce yield. Physodermabrownspot symptoms include infected leaves with many small round spots that are dark purple to black in color.Corn plants are most susceptible to Physodermabrownspot or stalk rot infection between V5 – V9. PhysodermaBrownSpotofCorn.Physodermabrownspot is more prevalent in wet growing seasons. Infection requires a combination of light, free water, and warm temperatures (75-85°F). Leaf infection occurs in the whorl when water is present for an extended time. Physodermabrownspot_stalk rot-breakage.jpg. Symptoms of Physoderma can be misdiagnosed as eyespot, common rust and southern rust, all more serious diseases ofcorn.
