ABSTRACT
From the research, a total of 132 isolates of 14 different fungal species belonging to 7 genera were isolated using dilution plate
technique on Potato dextrose agar incorporated with 1% streptomycin, from the upland and lowland agricultural fields of Usmanu
Danfodiyo University, Sokoto. Aspergillus, Fusarium, Rhizophus, Alternaria, Saccharomyces, Trichoderma and Trichophytum
were identified microscopically using lacto-phenol cotton blue method and macroscopically by comparing the cultural and
morphological features with the help of authentic fungal manual and taxonomic key. Highest occurrence was obtained in
Aspergillus species (34.85%), followed by Fusarium spp. (20.45%) and the least was obtained in Alternaria spp. having only
2.27%. It was found that, the soil pH and Mg (pH= 8.3, Mg= 1.33cmol/kg) were significantly higher (P< 0.05) in lowland cultivated
soil sample (C) when compared with upland cultivated (A), upland (B) and lowland uncultivated (D). No significant difference
was observed in soil pH and Mg among the Upland cultivated (A), Upland (B) and lowland uncultivated soil samples. Organic
carbon (OC), Nitrogen (N) and potassium (K) values differ significantly (P<0.05) among the treatments. A strong negative
significant correlation between fungal abundance and pH (-0.63) was observed at P<0.05, and also a negative, moderate and non-
significant correlation observed with sand availability (-0.43), while a weak and negative correlation exists between the fungi,
magnesium (Mg) and clay availability with -0.31 and -0.35 respectively. However, a very strong positive correlation exists between
the moisture contents (MC) 0.62, sodium (Na) 0.62 and the fungal abundance, with a moderate one between the fungi and organic
carbon (OC) 0.55, potassium (K) and phosphorus (P) with 0.51 all at P<0.05 significant level.