P. zeae-maydis), which is closely related to the oomycete or water mold fungi, such as the downy mildews. SyMptoMS: Northern corn leaf blight (NCLB) is typified by long (length: 1–6 in.) Avoid overhead irrigation. Thanks for asking about the brown spots on the leaves of your house and office plants. This disease is mostly seen on dracaena. lesions with tapered ends that are gray-green to tan lesions in color. They will be free from brown spots. Thanks too for sending photos. Figu re 3. Anthracnose lesions tend to be brown, oval to spindle-shaped lesions with yellow to pinkish to reddish-brown … Physoderma brown spot is caused by the fungus Physoderma maydis. This is often the caused when corn plant is placed in a bright window where the light can concentrate on one or more of the leaves. It will further cause brown dusting on the leaves as well as blooms. Anthracnose leaf blight, caused by the fungus Colletotrichum graminicola, usually occurs early in the season on the lower leaves of young corn plants. Leaf lesions are numerous, very small (approximately ¼ inch in diameter), round to oval, yellowish to brown in color, and usually occur in broad bands across the leaf. It is linked to high temperature and humidity. The disease will subsequently kill the leaf. Preventing Plant Leaf Spots On the ear the fungus causes oblong, bleached spots which penetrate through the shuck layers and finally into the ear. Light – Too much light can cause dry burnt patches on the leaves. The spots could be caused by a fungus or bacteria. Spots often enlarge and increase in number and can cause severe leaf blighting. Keep garden clean of debris and weeds which can harbor fungus spores. Plant resistant varieties. Brown spots may appear on the margins of leaves, on the tips of leaves or as round or irregular spots in the middle of the leaf. This disease is normally an infrequent, minor disease in corn that we observe during most years to a low degree in Nebraska. • Grayish or tan oval spots on leaves. Disease usually begins on lower leaves but can spread to all leaves and husks with secondary infections. Symptoms of Physoderma brown spot usually appear on mid-canopy leaves. Infected corn tissues cont ai n large numbers of sporangia that may be released as t he corn leaf ru pture s and dies. Leaf spot; Brown, yellow or black or water soaked spots will appear on the leaves. When lesions coalesce, the entire leaf can become blighted and symptoms resemble frost- Pathogen Physoderma brown spot is caused by the chytridiomycete fungus, Physoderma maydis (syn. Spots on the leaves are tan to light brown and occur first on the lower leaves of the plant. Physoderma brown spot of corn. Northern corn leaf blight and southern corn leaf blight are fungal diseases that favor wet conditions. Water and Fertilizer Look for signs of underwatering, which causes brown edges, wilting foliage and drop of new growth. Soon the circle grows large enough to touch another circle and now the fungal leaf spot looks more like a blotch. Add aged compost or organic material to planting beds to keep soil well-drained. Brown spot symptoms are most prominent in the leaf midrib area. Eventually the leaf turns brown and falls to the soil where the spores sit and wait for the next available warm, wet, plant surface so the fungal leaf spot process can begin again. Figu re 4. It is easy to detect this problem by view the leaves that are opposite of the window. Close-up of a corn leaf blade showing the chocolate brown blotches, an advanced stage of Physoderma brown spot. Poor air circulation will also cause the problem. The spots could also be the result of the care they were given such as too much …