Morphological and Cultural Characterization of Cercospora zeae-maydis Tehon and Daniels Isolates in Western Oromia Region, Ethiopia

摘要

Maize (Zea mays) is one of the most widely cultivated crops in the world. It occupies an important position in the world economy serving as food, feed, and industrial grain crop. Grey leaf spot (Cercospora zeae-maydis) is one of the major foliar diseases threatening maize production in Ethiopia. Most of the researchers estimated that losses as high as 100% occurred when the pathogen attacked before the flowering stage. Also, in Ethiopia the loss caused due to this disease reached 49.5%.Therefore, the objective of this paper was to study morphological and cultural characterization, of maize Grey leaf spot isolates. Morphological and cultural characterization studies of the 5 isolates were done at JUCAVM Plant Pathology lab and greenhouse, respectively. From 155 samples collected during the assessment, 52 isolates were re-cultured and grouped into 5 isolates. Accordingly Colony color showed (grey, light, brown, corn silk and white) on top, and (dark grey, brown, cornsilk3 and grey) on the reverse. Similarly, colony shape (round and irregular) Colony elevations were (Entire & Undulate) whereas Colony edges were Flat & Umbonate). Based on Conidial shape and number of septa isolates LD-G and DN-H were showed Slightly curved & isolates GS-O, IG-3, and LA-Ay were Straight, The highest number of septa was recorded on isolate LD-G with 6 and the minimum was recorded on DN-H with 4. Knowing the cultural and conidial characteristics of different isolates of C. zeae-mayydis is very important in the development of management option of the disease. Molecular diagnostics is very crucial to confirm their specific morphological differences and to design appropriate management options.