A RESEARCH PROJECT SUBMITTED TO THE DEPARTMENT OF BIOLOGY FACULTY OF CHEMICAL AND LIFE SCIENCES USMANU DANFODIYO UNIVERSITY, SOKOTO IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE AWARD OF THE DEGREE OF B.SC BIOLOGY

Abstract

Maize (Zea mays L.) is a major staple crop in Nigeria but suffers significant post-harvest losses due to fungal contamination during storage. Traditional storage methods often expose maize grains to poor aeration, high humidity and pest infestation, which encourage fungal growth and increase the risk of mycotoxin contamination. These losses reduce grain quality, nutritional value, and pose serious public health risks. This study was conducted in the Mycology Laboratory of Usmanu Danfodiyo University, Sokoto. Maize sampels were collected from silos, barns, warehouses and household storage facilities within the study area. Using Potato Dextrose Agar (PDA) and Sabouraud Dextrose Agar (SDA), fungal pathogens were isolated, cultured and identified through microscopic techniques. The findings revealed five fungal species: Aspergillus niger, Aspergillus flavus, Rhizopus oryzae, penicillium chrysogenum and Mucor racemosus. Among these, A. nigher was the most prevalent (53.33%), indicating high adaptability across divrse storage environments. A flavus was the second most common (20%), raising significant concern due to its aflatoxin-producing potential. Other fungi such as Rhizopus oryzae, Penicillium chrysogenum and Mucor racemosus occurred less frequently but were associated with particular storage conditions. These results demonstrate that environmental factors, espeiclaly humidity, aeration, and hygiene, stronglty influence fungal colonization of stored maize. In conclusion, A. niger poses the greatest threat to maize during storage, while A. flavus presents food safety risks linked to aflatoxins. To minimize fungal contamination, maize should be properly dried, stored under low-humidity, well-ventilated conditions and regularly inspected. Further research is recommended to explore advanced storagte technologies and management strategies.