Location: Mycotoxin Prevention and Applied Microbiology Research
Title: First report and characterization of Fusarium meriodinale, F. boothii and F. temperatum causing preharvest maize ear rot in EthiopiaAuthor
TEMESGEN, DERESSA - Jimma University | |
ADUGNA, GIRMA - Jimma University | |
MAHABALESWARA, SURESH - International Maize & Wheat Improvement Center (CIMMYT) | |
BEKEKO, ZELALEM - Ethiopia Haramaya University | |
Iriarte Broders, Gloria | |
Vaughan, Martha | |
Proctor, Robert | |
Mehl, Hillary | |
PRASANNA, BODDUPALLI - Ethiopia Haramaya University | |
Opoku, Joseph |
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/3/2024 Publication Date: N/A Citation: N/A Interpretive Summary: Corn is an important staple crop in Ethiopia and serves as a source of livelihood and food for most farmers and the entire population. Even though several factors negatively affect corn production, corn ear rot disease is among the most destructive. Corn ear rot disease can reduce the quality, quantity, and safety of the grain leading to financial loss to the grower and health issues to humans and animals. To better understand which fungi cause the corn ear rot disease, ARS researchers in Peoria, Illinois, in collaboration with researchers in Ethiopia, performed a survey of corn-growing regions in 2020 and 2021. Fusarium fungi causing corn ear rot were isolated and identified using morphological and molecular methods. Three Fusarium species not previously known to cause corn ear rot in Ethiopia, were found including F. temperatum, F. boothii, F. meridionale. The highest frequencies of these emerging Fusarium species were found in the Oromiya region. Knowledge of which species are causing ear rots should be taken into consideration when developing disease management strategies such as breeding for host resistance. Technical Abstract: Ear rots caused by Fusarium species are some one of the most important diseases affecting maize production in Ethiopia. Fusarium ear rot (FER) and Giberella ear rot (GER) contaminate maize ears with mycotoxins which potentially impact human and animal health. A survey was conducted in 20 districts in major maize-growing areas of Ethiopia to identify Fusarium spp. associated with ear rot. Maize ears with FER and GER ear rot symptoms were randomly collected (10 ears per field, 12 fields per district). Fusarium spp. were isolated and morphologically identified. Molecular characterization was done by sequencing a portion of the translation elongation factor 1-a (TEF1) gene and two non-contiguous fragments of the RNA polymerase II subunit (RPB2). Phylogenetic tree was constructed with concatenated sequences of the two genes. Among the recovered isolates some were molecularly identified as F. boothii, F. meridionale and F. temperatum which have not previously been reported in Ethiopia. Koch's postulate was carried out for the isolates, and it was confirmed that they cause maize ear rot. This study represents the first report of the occurrence of F. boothii, F. meridionale and F. temperatum as casual agents of maize ear rot in Ethiopia. Specific causal agents of maize ear rots should be taken into consideration when developing disease management strategies such as breeding for host resistance. |