Assessment of Quality, Fungal Population and Diversity, of Irrigation Water in Selected Areas of Minna, Niger State, Nigeria

Water samples were collected at 3 slope positions (upper, middle and lower) from four locations practising irrigation agriculture in Minna as follows; Fadikwe, Mechanic village in keterin-gwari, Soje-A in kpakungu and Bali in Chanchaga and fitted to a Completely Randomized Design (CRD) having slope positions as replicates for each treatment. Water sampling, Physical and chemical properties and Fungi population and diversity were determined using standard methods. Data generated were subjected to Analysis of Variance (ANOVA) and means were separated using Least Significance Differences (LSD) and Duncan Multiple Range Test. Result obtained revealed that Chanchaga irrigation water recorded the highest fungi population of 1.6 x 107 CFU/ml why fungi diversity was the least at Chanchaga. The presence of _Geotrichum species_ (2.33 x 106CFU/ml), _Candida tropicalis_ (4.33 x 106CFU/ml) and _Torulopsis glabrata_ (1.67 x 106CFU/ml) in water obtained from Mechanic village may be due to the presence of hydrocarbons in the oil polluting the water. They are potential degraders of crude oil hydrocarbons. They may therefore be responsible for the value of Biochemical Oxygen Demand of 261 mg/l recorded at Mechanic village. The Biochemical Oxygen Demand values of 342 mg/l and 360.00mg/l recorded at Fadikwe and Soje A respectively may be due to the presence of _Aspergillus niger.Aspergillus niger_ is a utility biological indicator of level of degradation of pollutant. These values were however higher than the Food and Agriculture organisation (FAO) standards for irrigation water. Further studies should however be carried out to investigate the bioremediating potentials of the fungi species identified in irrigation water obtained from Chanchaga.