Corn grey leaf spot

Cercospora zeae-maydis on corn

Grey leaf spot (GLS) is a foliar fungal disease that affects maize, also known as corn. GLS is considered one of the most significant yield-limiting diseases of corn worldwide.[1] There are two fungal pathogens that cause GLS: Cercospora zeae-maydis and Cercospora zeina.[2][3][4] Symptoms seen on corn include leaf lesions, discoloration (chlorosis), and foliar blight. Distinct symptoms of GLS are rectangular, brown to gray necrotic lesions that run parallel to the leaf, spanning the spaces between the secondary leaf veins.[1] The fungus survives in the debris of topsoil and infects healthy crops via asexual spores called conidia. Environmental conditions that best suit infection and growth include moist, humid, and warm climates.[5][3][4] Poor airflow, low sunlight, overcrowding, improper soil nutrient and irrigation management, and poor soil drainage can all contribute to the propagation of the disease.[5] Management techniques include crop resistance, crop rotation, residue management, use of fungicides, and weed control. The purpose of disease management is to prevent the amount of secondary disease cycles as well as to protect leaf area from damage prior to grain formation. Corn grey leaf spot is an important disease of corn production in the United States, economically significant throughout the Midwest and Mid-Atlantic regions. However, it is also prevalent in Africa, Central America, China, Europe, India, Mexico, the Philippines, northern South America, and Southeast Asia.[6] The teleomorph (sexual phase) of Cercospora zeae-maydis is assumed to be Mycosphaerella sp.[7]

  1. ^ a b "Managing Northern Corn Leaf Blight". Channel.com. Retrieved 18 March 2022.
  2. ^ Ward, J. M. J., E. L. Stromberg, D. C. Nowell, and F.W. Nutter, Jr. 1999. Gray leaf spot: A disease of global importance in maize production. Plant Disease 83: 884-895
  3. ^ a b Cairns, J.E.; Sonder, K.; Zaidi, P.H.; Verhulst, N.; Mahuku, G.; Babu, R.; Nair, S.K.; Das, B.; Govaerts, B.; Vinayan, M.T.; Rashid, Z.; Noor, J.J.; Devi, P.; San Vicente, F.; Prasanna, B.M. (2012). "1 Maize Production in a Changing Climate: Impacts, Adaptation, and Mitigation Strategies". Advances in Agronomy (PDF). Vol. 114. Elsevier. pp. 1–58. doi:10.1016/b978-0-12-394275-3.00006-7. ISBN 978-0-12-394275-3. ISSN 0065-2113.
  4. ^ a b Tripathi, Ashutosh; Tripathi, Durgesh Kumar; Chauhan, D.K.; Kumar, Niraj; Singh, G.S. (2016). "Paradigms of climate change impacts on some major food sources of the world: A review on current knowledge and future prospects". Agriculture, Ecosystems & Environment. 216. Elsevier: 356–373. doi:10.1016/j.agee.2015.09.034. ISSN 0167-8809.
  5. ^ a b "Cercospora leaf spot".
  6. ^ Crous PW, Braun U (2003). Mycosphaerella and its anamorphs. 1. Names published in Cercospora and Passalora. CBS Biodiversity Series 1: 1–571.
  7. ^ Nyvall, Robert F. “Field Crop Disease”. Wiley-Blackwell, 1999, p. 282.