IITA IPM project 28: Diversity in Fusarium species causing stalk and ear rot of maize and sorghum in West Africa

Duration: 3 years (2003 to 2005)

Purpose: To determine the diversity Fusarium species infecting maize and sorghum to understand the distribution of these species in different agroecologies in West Africa. Knowledge of the identity of the pathogen is a pre-requisite to develop strategies for the management of crop damage due to Fusarium species

Background/description: Fungi in the genus Fusarium cause serious losses due to stalk rots, ear rots, and grain mold in both maize and sorghum, which are sometimes grown in the same agroecosystem. Some Fusarium species produce mycotoxins that contaminate food and feedstuffs. Mycotoxins are detrimental to human and animal health. Risks associated with Fusarium toxins are usually assessed based on the Fusarium species present, as not all species produce all toxins. Our hypothesis is that Fusarium species occurring on maize and sorghum are diverse, and may have been commonly confounded in the past, probably all identified as F. moniliforme, resulting in the confusingly different toxicological and phytopathogenic properties that are simultaneously attributed to F. moniliforme. To distinguish strains and species of Fusarium various genetic and molecular techniques are now routinely used. However, the new tools for characterization of Fusarium species are not currently used by the NARS of tropical Africa. This project would train key plant pathologists from several West African countries in Fusarium research using new tools.

Agroecozone(s) and location(s): Humid Forest, moist savanna, and dry savanna in Nigeria, Ghana, Cameroon and Burkina Faso

Expected outputs: Diversity in Fusarium species infecting maize and sorghum would be understood for better targeting resistance to diseases caused by specific species. National program scientists from several African nations would be trained in appropriate methods used in identification of Fusarium species. These scientists would be able to apply this knowledge not only on maize and sorghum diseases, but also on other crops. The main outputs a) Characterize and compare Fusarium species infecting maize, and sorghum in several West African countries using molecular and genetic tools; b) determine the mycotoxin profile of Fusarium species infecting maize and sorghum in West Africa; c) Train scientists from different African national programs in new methods to identify Fusarium species.

Potential impact and beneficiaries: To ensure better targeting, host plants can be challenged with well-characterized pathogens with known host range, geographic specificity, and mycotoxin profile. In other words, it will improve methods to breed for resistance and its deployment in specific areas. Mycotoxin profile of species and their geographic occurrence would prioritize research on management of specific mycotoxins in different areas. Modern tools used in Fusarium taxonomy would be instituitionalized at IITA from where further training of NARS scientists can be performed

Partners: a) Kansas State University, Manhattan, Kansas; b) INERA, Burkina Faso, c) SARI, Ghana; d) IRAD, Cameroon.

Development investor(s): USAID Linkage grant

IITA contact person(s)/principal investigator(s): Ranajit Bandyopadhyay R.Bandyopadhyay@cgiar.org website http://www.iita.org