Variability, Epidemiology and Yield Loss Caused by Northern Leaf Blight (Exserohilum Turcicum (Pass.)) of Maize (Zea Mays L.) in Tanzania
$ 64.5
Description
Surveys for northern leaf blight (NLB) disease of maize were conducted in 480 farmers’ fields in Arusha, Coastal, Iringa, Mbeya, Morogoro, Kilimanjaro and Njombe Regions, in 2012/13 to establish intensity, distribution and identify resistant maize cultivars under natural infection. Results showed prevalence of the disease with incidence of 57.5-96 % and severity index of 33.4-62.2 %, which were high in the humid highlands of Mbeya and Arusha. There were positive significant (P ≤ 0.05) correlation coefficients between disease incidence, severity index, altitude, relative humidity and rainfall, and negatively significant differences (P ≤ 0.05) between incidence, severity index, minimum and maximum temperatures. Regression coefficient (R²) associated 38.2 % NLB severity to environmental factors.