ABSTRACT
This study was conducted to investigate and compare the kind and amount of fungi associated with soils of different farmlands within Benin metropolis, in a particular community (Iyowa community) within a local government area, Ovia North East, Benin city, Nigeria. Four different farmlands were selected comprising of fruity vegetables (Cucumis sativus), Leafy vegetables (Amaranthus sp.), root tubers (Dioscerea sp.) and stem tubers (Manihot esculenta). Soil samples at these locations were collected in triplicates at the rhizophere and at 10cm below the ground in sterile and labelled containers provided for sampling.
The packaged and labelled samples were immediately transported in clean and airtight foodflasks to the laboratory for mycological analysis. The serial dilution method of Harrigan and McCance (1976) was aseptically carried out in tubes. Sterile test tubes were used for the ten-fold dilution. . Test tubes labelled: 10-1,10-2,10-3,10-4,, were used for each of the samples and one gram (1.0 gm.) of each of the samples was weighed out, mixed with nine milliliters of sterile distilled water into a test tube. One milliliter (1.0 ml) of the aliquot was obtained from each of the samples and transferred into the test tube labelled 10-1 and mixed properly. One milliliter (1.0 ml) aliquot was then transferred serially from the tube (10-1) to tubes labeled 10-2,10-3, and 10-4, in that order. Aliquots from the appropriate tubes were then used to inoculate appropriate media for isolation of fungi using the pour plate method on potato dextrose agar (PDA). The agar plates were then incubated at room temperature (28±20C) for 3- 5days. After incubation, standard morphological, cultural, biochemical tests were used to identify isolates from culture plates.
Results revealed the presence of fungi namely Aspergillus niger, Aspergillus flavus. Aspergillus tamari, Aspergillus nidulans, Mucor sp., Mucor mucido, Sacharomyces sp., Cream yeast, Cryptomonas neoformis, Brown yeast, Penicillum oxalicum, Penicillum italicum, Penicillum sp., Trichoderma sp., Chaonophora sp. and Clasdosporium sp. The fungi frequency of the samples ranged from 5-7. The fungi percentage frequency ranged from 8.8% to 14.0%. The fungi diversity ranged from 3-6. The fungi percentage diversity ranged from 42.9% to 85.7%. The total estimated heterotrophic fungi counts in colony forming unit per gram (cfu/g) of soil samples ranged from 1.3±0.9 to 7.0±1.0.
