Inaugural lectures

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    Savanna
    (John Wiley, 1986) Sanford, William W.; lsichei, Augustine O.
    Very obviously, fire decreases the density of woody stems and late (intense) burning has a greater effect than early burning. In very humid savanna (as in derived savanna regions) the wood volume may sometimes be greater in early burnt plots than in fire protected ones in early successional stages, as smaller mean girth in the fire-protected area may not be compensated for by the increase in stem density. The effect of fire on herbaceous production varies greatly with climate. In drier, more marginal regions early burning or even fire protection may result in higher grass yields than late burning. In the southern derived savanna, time of burning makes little difference in yield, but somewhat greater yield is achieved with late burning. In intermediate (Guinea savanna) regions, late burning usually appears to increase grass above-ground biomass, although no results of long-term experiments are available.
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    Composition, Structure and Soil Relations of Isoberlinia Woodlands in Nigeria
    (1998) UBOM, R. M.; ISICHEI, A. O.
    Isoberlinia woodlands in Northwestern Nigeria were studied with a view to elucidating the species composition, and soil-vegetation relationship. Cover, density, height, basal area and frequency were determined for shrubs and trees. Soil properties measured included particle size, exchangeable cations, organic carbon pH, field moisture and total nitrogen. Principal component ordination of the vegetation data produced five community types. The community structure was define by the variation in density and dominance of few species such as Isoberlinia sp. Burkea Africana and Vitellaria Paradoxa (syn. Butyrospermum paradoxum). The size structure of trees indicated differences in the community-type stature and physiognomy. Variation in species composition and ecological status of tress were related to environmental gradients of soil properties.
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    Whatever Goes Up Must Come Down? The Environmental Consequences of Nutrient Cycling in Vegetation
    (Obafemi Awolowo University Press., 2002) Isichei, Augustine O.
    I studied plants individually or in groups and investigated how they interacted with their immediate environment and recycled energy and matter. I started my enquiry with attempts to understand how ecological phenomena operate in the Nigerian environment. I carried out my enquiries as a natural scientist with the hope that I can contribute to our understanding of the world around us and supply information to applied scientists for use in technological applications.
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    Leaf Epidermal Studies of the Species of Emilia Cass. (Senecioneae, Asteraceae) in Nigeria
    (2004) Adedeji, Olubukola
    A taxonomic study of Emilia Cass. in Nigeria was conducted in search of useful and stable anatomical characters for the identification of the species. Stomatal type and index indicates that Emilia praetermissa is a hybrid between E. coccinea and E. sonchifolia. Larger cell size in all studied size attributes supports E. praetermissa as an allotetraploit. Trichome type, stomata type, stomata shape and size attributes are all characters of E.sonchifolia and E. praetermissa that were consistently close in resemblance and values to suggest E. sonchifolia as the closer parent of E. praetermissa exerting gene dominance. This would also suggest introgression between E. sonchifolia and E. praetermissa.
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    Studies on the Reproductive Biology of Emilia (Asteraceae - Senecioneae) I. Flowering and Post-pollination Developments in the Capitulum
    (Swedish Museum of Natural History, 2005) Adedeji, O.
    A study of the flowering and post-pollination developments in the capitulum of the genus Emilia (CASS.) CASS. (Asteraceae - Senecioneae) was conducted in order to correlate and document various observations made on the stages of development of floral parts. The protectional role of floral parts is highlighted, both while flower is in bud and at fruit development phase. The co-operative features of floral parts (phyllaries, florets and receptacle) in the display of flowers for pollination and fruits for dispersal are elaborated. The probable reasons for the usual occurrence of E. sonchfolia and E. coccinea as isolated populations are discussed.
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    Chemical Composition of a Tropical Fern Ceratoptelus Cornlita (Parkeriaceae, Pteridophyta) in Nigeria
    (2010) Oloyede, F. A.; Oloyede, F. M.; Saliu, T. L.; Ogunwole, A. A.
    Extracts from some fern species have been found to be useful in fortifying livestock and fish feeds to enhance production especially in peasant communities. The chemical composition of Ceratoptc.ris cornzltn has not been documented insNigeria. This study was thus designed to determine its suitability for use in fortifying fish feed by analysing the nutrient and anti-nutrient contents of its dimorphic fronds separately. One kg of sterile and fertile fronds of C.cornuta were collected, washed using distilled water and oven dried at 40 OC for about 96 hours. The dried samples were milled and analysed for proximate minerals, cyanide and oxalate analyses in triplicates. Results of the nutrient and anti-nutrient analyses show that both the sterile and the fertile fronds of C. cornuta can be used in aquaculture. The crude protein (4.22-5.28 g/100 g), moisture (87-91.00 g/100 g), carbohydrate (3.12-7.40 g/100 g), magnesium (23.55-194.65 mg/100 g), calcium (0.03 mg/100 g), potassium (0.17 mg/100 g), sodium (0.17 mg/100 g), silver (50.0 mg/100 g), cobalt (3.75-4.45 mg/100 g), lead (53.5-172.5 mg/100 g), copper (60.45-61.0 mg/100 g), manganese (15.65 mg/100 g), arsenium (50 mg/100 g), cadmium (3.75-4.50 rng/100 g), iron (430.00-537.45 mg/100 g) and selenium (106.83-195.45 mg(100 g) contents are considerably high. The anti-nutritional oxalate (0.861.38 mg/100 g) and cyanide (0.88-1.16 mg/100 g) are low and fall within the safe and acceptable limits as recommended by the World Health Organisation. Thus, extract from these fronds can be incorporated into livestocks and fish meals.
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    Comparative Foliar Anatomical And Morphological Studies of Nephrolepis Biserrata (Swartz) Scott And N. Undulata ( Swartz) J.SM. in Nigeria
    (Kwame Nkrumah University of Science and Technology (KNUST), 2011) Oloyede, F. A.; Akomolafe, F. G.; Oladipo, O . T.
    The foliar anatomy and morphology of Nephrolepis biserrata and Nephrolepis undulata were investigated. The aim of which is to elucidate their taxonomic knowledge with the use of both foliar anatomical and morphological characteristics that exist between them. The anatomical studies carried out include shape and size of the epidermal cell, venation patterns, stomata type and distribution. One way analysis of variance was used to show whether the two taxa are significantly different. The results of anatomical similarities in the adaxial surfaces of their leaflets were sinuous, anticlinal walls, absence of stomata and trichome, epidennal cells are irregular in shape and variable in sizes. On their abaxial surfaces, epidermal cells are irregular in shapes and variable in sizes, stomata present, predominantly diacytic and anomocytic types with elliptic shapes, thin and wavy anticlinal wall. Anatomical differences include length and width of epidermal cells, absence or presence and distribution of crystal sands, thickness of anticlinal walls on the adaxial surfaces, stomata Index and frequency, length and breadth of guard cell and guard cell area. The venation patterns showed that the mid-rib is sheathed with parenchyma cells and trichome types were observed in N. biserrata but absent in N. undulata. The distinguishing characters of the two taxa studied are of taxonomic value and can be used to identify and delimit each species and thus widen the scope of their taxonomic knowledge.