Samples of dry-roasted groundnuts purchased from street hawkers, markets and retail shops in southwestern Nigeria were analysed for moisture content, fungal populations and aflatoxin contamination. The moisture content varied from 2.1 to 3.6 per cent, while the mould counts using the dilution plating method ranged from 2.9 £ 10 2 to 6.3 £ 10 2 colony-forming units per gram in samples. Aflatoxin B 1 was found in 64.2 per cent of samples with a mean of 25.5 ppb. Aflatoxins B 2, G 1 and G 2 were detected in 26.4, 11.3 and 2.8 per cent of the samples with mean levels of 10.7, 7.2 and 8 ppb respectively in contaminated samples. It is concluded that the regular consumption of DRG by Nigerians might present potential health hazards.

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The mycoflora, moisture content and aflatoxin contamination of pigeon pea (Cajanus cajan (L.) Millisp) stored in jute sacks and iron bins were determined at monthly intervals for a year. The predominant fungi on freshly harvested seeds were Alternaria spp., Botryodiplodia theobromae, Fusarium spp. and Phoma spp. These fungi gradually disappeared from stored seeds with time and by 5-6 months, most were not isolated. The fungi that succeeded the initially dominant ones were mainly members of the general Aspergillus, Penicillium and Rhizopus. Population of these fungi increased up to the end of one year storage. Higher incidence of mycoflora and Aspergillus flavus were recorded in jute-sack samples throughout the storage period. The moisture content of stored seeds was found to fluctuate with the prevailing weather conditions, being low during the dry season and slightly high during the wet season. The stored seeds were free of aflatoxins for 3 and 5 months in jute sacks and iron bins respectively. The level of aflatoxins detected in jute-sack storage system was considerably higher than that occurring in the iron bin system. Of 196 isolates of A. flavus screened, 48% were toxigenic in liquid culture (54% from jute sacks and 41% from iron bins).

The fungi associated with rot of Vitex doniana fruits (blackplum) were isolated and identified. Aspergillus niger, Botryodiplodia theobromae, Candida spp. Penicillium chrysogenum, Rhizopus stolonifer, Fusarium pallidoroseum F. oxysporum and Mucor mucedo were the primary rot causing fungi in contrast to Cladosporium herbarum and Mucor circinelloides which were just present as secondary colonizers. The rot fungi penetrated mainly through wounds and bruises on the surface of fruits. Mature green fruits were less susceptible to infection than half ripe and fully ripened red fruits. Optimum rot by pathogenic isolates occurred at 25-30 degrees C and relative humidity 72.5-100%. The results of investigation of influence of storage temperatures and relative humidity on the quality of uninoculated healthy fruits are presented and discussed.

This study presents investigations into the epidermal and phytochemical features of Eragrostis tremula (S.W.Beauv.), Cymbopogon citratus (Stapf.) and Axonopus compressus.(P.Beauv.). Epidermal features of the different species in the three genera showed slight differences for both the adaxial and abaxial parts with respect to prickles, papillae, macro hairs and micro hairs. Long cells, short cells, stomata and silica bodies are almost universally present in all the three species. With respect to their phytochemical characteristic, Cymbopogon citratus tested positive for alkaloid, saponin, inulin, cellulose, tannin and lignin; Eragrostis tremula tested negative for lignin and positive for cellulose, saponin and alkaloids while Axonopus compressus tested negative for lignin, but positive for alkaloid, saponin, inulin, cellulose and tannin respectively. Leaf epidermal studies help to determine patterns of variation in plant species thus helping in our knowledge of such species. It is useful in determining their different morphological, epidermal and phytochemical characteristics thus helping in the assessment of its values in species identification, classification and in establishing a taxonomic relationship between different species being studied.