International Journal of Pure & Applied Bioscience (IJPAB)
Year : 2015, Volume : 3, Issue : 5
First page : (1) Last page : (13)
Article doi: http://dx.doi.org/10.18782/2320-7051.2086
Disease Intensity and Distribution of Exserohilum turcicum Incitant of Northern Leaf Blight of Maize in Tanzania
Nwanosike, M. R. O1., Mabagala, R. B². and Kusolwa, P. M².
1Department of Agric. Education, Federal College of Education, P.M.B. 1041, Zaria, Nigeria
²Department of Crop Science and Production, Faculty of Agriculture, Sokoine University of Agriculture, P.O. Box 3005, Morogoro,Tanzania
*Corresponding Author E-mail: martinroyal2002@yahoo.com
Abstract
Maize (Zea mays L.) is widely cultivated across regions in Tanzania. To understand the relationship between maize and epidemics of northern leaf blight, surveys were conducted in 2012 and 2013. Disease incidence and percent severity were determined in 280 farmers’ field. Each sampled point measuring about one acre at intervals of 500 meters was marked with global positioning system and used to construct the disease map. Data was subjected to ANOVA and means separated with Turkey’s-kramer simultaneous test at P≤ 0.05. Northern leaf blight (NLB) disease was found in all the fields studied, however the level of virulence differed. The disease incidence (57.5 - 96 %) and percent severity (33.4 – 62.2 %) were significantly more severe in humid highlands of Mbeyaand Arusha districts compared to incidence (11.8 - 61.3 %) and severity (3.9 – 34.5 %) in the lowland dry Coastal and Morogoro districts. Significant correlation coefficients (p ≤ 0.05) and coefficient of determination (R² = 0.36 and R² = 0.38) between disease incidence, percent severity and environmental factors confirmed that NLB spread in maize was proportional to high altitude, low temperature, high relative humidity and rainfall.The results from this study suggested that (i) Mbeya was a hotspot area for NLB and therefore can be used to screen germplasms for resistance to NLB, (ii) host resistance and susceptibility was influenced by location and environmental factors and (iii) frequent surveys in the studied areas and beyond will be imperative to identify source(s) of resistance and pathotypes/races of the pathogen in Tanzania.
Full Text : PDF; Journal doi : http://dx.doi.org/10.18782
Cite this article: Nwanosike, M.R.O., Mabagala, R.B. and Kusolwa, P .M., Disease Intensity and Distribution of Exserohilum turcicum Incitant of Northern Leaf Blight of Maize in Tanzania, Int. J. Pure App. Biosci. 3(5): 1-13 (2015). doi: 10.18782/2320-7051.2086
