Occurence of Aspergillus flavus and Aspergillus parasiticus in stored maize in Morogoro municipality and Makambako district,Tanzania

Abstract

Maize is an important cash and food crop grown in Tanzania and other parts of the world. The crop is susceptible to fungal infestation and subsequent mycotoxins contamination that negatively affects human and animal health as well as the socio-economic status of the farmers and respective stakeholders. The study was conducted to determine occurrence of aflatoxigenic fungi (A.flavus and A.parasiticus) on maize stored in warehouses found in Morogoro municipality and Makambako district in Tanzania. A total of 226 maize samples were collected from six wards in the selected study areas then analysed for aflatoxigenic fungal infestation. Potato Dextrose Agar was used for isolation of the fungi which were then identified to species level via observation of morphological characteristics with aid of taxonomic keys. The proportional occurrence of A. parasiticus and A. flavus with respect to areas where samples were collected was presented using descriptive statistics. The result showed that only 15% (34/226) of the collected samples were contaminated with Aspergillus flavus and Aspergillus parasiticus. Among the samples collected, the occurrence of A. flavus was higher than that of A. parasiticus whereby 28 samples were contaminated with A. flavus while 6 samples with A. parasiticus. We found that the methods used in the storage of this major staple food used by majority of Tanzanians makes it vulnerable to infestation and subsequent contamination by aflatoxigenic fungi. We therefore recommend that responsible sectors should implement appropriate intervention strategies designed to reduce occurrence of aflatoxigenic Aspergillus species on stored maize.