Browsing by Author "Olubode, O.S."

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Assessment of soil seedbank composition, woody species composition and structure in olokemeji forest reserve, ogun state, nigeria.
(2017) Taiwo, D.M.; Olubode, O.S.; Oyelowo, O. J.
Olokemeji forest reserve has undergone tremendous changes through anthropogenic impact on the forest ecosystem, such human impacts include farming activities, logging of wood and burning. The soil seed bank composition, woody species composition and structure were studied with a view to determine the restoration potential of the forest reserve. Six sample plots (Frequently burnt plot 1, Frequently burnt plot 2, Harvested plot, Unharvested Unburnt plot, Arable plot 1 and Arable plot 2) designated as FT1, FT2, HP, UP, AP1 and AP2 were randomly selected. Floral species identification, relative importance value (RIV), species diversity and multivariate analysis all followed standard procedures. Three replicate soil samples were collected at two different depths (0-15 cm and 15-30 cm) from each plot and they were subjected to seedling emergence for five months to determine the species composition, density and diversity of the seed banks of the six study plots. The results of seedling emergence showed that soil collected at 0-15 cm depth had a higher RIV, species diversity, individual, abundance and dominance index than soil collected at 15-30 cm depth. However, the evenness index for seedlings in the soil seed bank was considerably high across the two soil depths which depicted equal measure of spread within each study plots at both soil depths. Tectona grandis was highest in RIV. The dominance index for the woody flora was 1 in frequently burnt Plot 1 and 2 as well as Arable Plot 1 and 2 except for the Harvested Plot that had the lowest (0.29) while the . Unharvested unburnt Plot had 0.75. The diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested unburnt Plot (0.43). Trees in Unharvested unburnt Plot had the highest mean diameters at breast height, basal areas and mean heights, while the Arable Plots had lowest mean diameters at breast height, mean basal areas and mean heights.
Climate change, impacts and mitigation: Nigerian experience
(2010) Ogunyemi, S.; Awodoyiu, R.O.; Olubode, O.S.
Climate has continued to change for millennia. The various anthropogenic factors have accelerated the change to the extent that what used to be subtle natural changes have become measurable and observable changes. These anthropogenic factors have resulted in the generation of greenhouse gases (GHGs) and their emission to the atmosphere and the depletion of the ozone layer. The GHGs, especially carbon dioxide (COz) generated from various combustion activities; methane (CHf generated from rice paddies and flooded areas as a result of anaerobic fermentation, and from ruminating cattle and nitrous oxide (NfO) generated from decomposition of nitrogen fertilizers and livestock wastes trap some of the heat (infrared) that radiate from the earth. The ozone layer at the upper stratosphere which shields the earth specifically from the ultraviolet (UV) light is constantly being destroyed by the immense quantities of chlorine released by volcanoes and other natural emissions, and by chlorine releasedfrom human-made chlorofluorocarbons (CFC, HCFC, HFC, PFC). The most visible effect of climate change is global warming, which has disrupted the thermodynamic balance of the earth, with some regions unnaturally gaining more heat than the others. This rise in earth temperatures has resulted in continued melting of ice caps, glaciers and sea ice, resulting in a rise in global sea levels of between 20cm and 60cm. The Nigerian Niger Delta is under threat of climate related flooding, habitat destruction and species loss. The coastal erosion in the Niger Delta occasioned by sea-level rise is already a menace, especially, regarding destruction of mangrove vegetation which constitutes an important stabilizing system in the brackish ecosystem. Already, 18,803 square kilometers was reported destroyed and 0.21 million people displaced by up to 2-meter coastal sea-level rise. The receipt of increased UV on earth not only increased the temperature on earth, but has serious implications on human health, causing melanoma skin cancer, cataracts and sunburn and altering human's immune system. Afforestation, reforestation, zero-tillage, replacement offossilized fuels with environment-friendly fitels and energy sources like bio-diesel and sustained public awareness programmes are suggested as ways to mitigate the emission of GHGs.
Complexities of local cultural protection in conservation: the case of an endangered African primate and forest groves protected by social taboos
(2017) Baker, L.R.; Tanimola, A.A.; Olubode, O.S.
Globally, some species and habitats receive protection through local belief systems (e.g. indigenous religions) and informal institutions (e.g. social norms and taboos). Where such systems represent the only form of protection for threatened species or environments, they may be critical to the survival of those taxa and sites. We evaluated the effectiveness of long-standing social taboos protecting the Endangered Sclater’s monkey Cercopithecus sclateri and forest groves in a community complex in Nigeria. Across its range (southern Nigeria), Sclater’s monkey is effectively protected only through informal institutions. At our study site, we conducted a census of the monkey population; measured the area of sacred groves; and compared our findings with estimates from  and , respectively. We observed a % increase in the monkey population (from  to  individuals) in a core survey area. No groves that we assessed in  had been fully cleared. Although we observed a decline in tree cover for several sacred forests, most groves used regularly by monkeys had changed little. The social taboos related to monkeys and sacred groves remain largely intact; however, other factors threaten the monkey population and remaining forests in this community complex, including the removal of tree patches to accommodate the construction of large residential buildings and the demand for cropland, as well as increased dumping of waste in forested sites. This study highlights the conservation importance and limitations of local cultural protection, as well as the challenges presented when such protection conflicts with community-perceived
Considerations for using occupancy surveys to monitor forest primates: a case study with sclater’s monkey (cercopithecus sclateri)
(2011) Baker, L.R.; Todd, W.A.; Olubode, O.S.; Garshelis, D.L.
Count-based indices and distance sampling are widely used to monitor primate populations. Indices are often confounded by variation in detectability, whereas distance sampling is generally ineffective with species that flee or hide from observers and where it is difficult to accurately measure detection distances. We tested occupancy modeling as a means to monitor Sclater’s monkey (Cercopithecus sclateri), an endemic of Nigeria. We evaluated effects of survey methodology, habitat, and human disturbance on detection probability and site occupancy. Average detectability was high (p = 0.81), but varied substantially between two observers. Occupancy was highest in areas with intermediate levels (20–40%) of farmland and secondary forest, and was unaffected by human disturbance. Sampling plots (4 and 6.25 ha) did not concurrently contain[1 monkey group, were likely closed to monkey movements during the replicate surveys of each plot, and were spatially separated so that it was unlikely the same group was observed in [1 plot. These conditions enabled the conversion of occupancy to group density. Scaled to 6.25 ha, model-weighted occupancy averaged 0.230 (SE 0.103), yielding an estimate of 3.7 groups/km2 (95% CI 1.4–7.7 groups/km2). Because some groups straddled plot boundaries, we assumed that half of these groups were inside the plots, resulting in an adjusted estimate of 3.1 groups/km2. Our results illustrate that occupancy can be suitable for monitoring vigilant forest primates where detection distances are difficult to measure. However, special attention is required to choose spatial and temporal scales that accommodate the method’s closure and independent-detection assumptions.
Correlates with the distribution and abundance of endangered sclater’s monkeys (Cercopithecus sclateri) in Southern Nigeria
(Blackwell Publishing Ltd, Afr. J. Ecol., 2007) Baker, L.R.; Olubode, O.S.
A distribution survey of the endangered Sclater’s monkey (Cercopithecus sclateri) was conducted over a wide area in southern Nigeria using forest surveys and hunter interviews. Sclater’s monkey, Nigeria’s only endemic primate species, is restricted to a land area of about 28,500 km2 in the densely human-populated, oil-producing region of southern Nigeria. Results indicate that this species is not as rare as previously thought; we confirmed its presence in 27 formerly unknown sites. Based on encounter-rate and distribution data, Sclater’s monkey is one of the two most abundant diurnal primate taxa across its range. However, the species primarily occupies isolated and degraded forest fragments. Although hunting is widespread, selective hunting of larger-bodied primate taxa offers some respite for the smaller Sclater’s monkey. We encountered this species more frequently in forests with relatively high hunting pressure, possibly indicating competitive release in the heavily hunted forests of southern Nigeria. Long-term persistence of Sclater’s monkey, which has no official protection throughout its range, depends on the willingness of hunters to target smaller-bodied wildlife (effortprofit trade-off), local bushmeat demand and protection of key forest fragments and the few larger forests in the region.
Distribution and abundance of sacred monkeys in igboland, Southern Nigeria
(Wilcy-Liss, Inc., 2009) Baker, L.R.; Tanimola, A.A.; Olubode, O.S.; Garshelis, D.L.
Although primates are hunted on a global scale, some species are protected against harassment and killing by taboos or religious doctrines. Sites where the killing of sacred monkeys or the destruction of sacred groves is forbidden may be integral to the conservation of certain species. In 2004, as part of a distribution survey of Sclater’s guenon (Cercopithecus sclateri) in southern Nigeria, we investigated reports f sacred monkeys in the Igbo-speaking region of Nigeria. We confirmed nine new sites where primates are protected as sacred: four with tantalus monkeys (Ch'lorocebus tantalus) and five with mona monkeys (Cercopithecus mona). During 2004-2006, we visited two communities (Akpugoeze and Lagwa > previously known to harbor sacred populations of Ce. sclateri to estimate population abundance and trends. We directly counted all groups and compared our estimates with previous counts when available. We also estimated the size of sacred groves and compared these with grove sizes reported in the literature. The mean size of the sacred groves in Akpugoeze (2.06 ha, n = 10) was similar to others in Africa south of the Sahel, but larger than the average grove in Lagwa (0.49 ha, n = 15). We estimated a total population of 124 Sclater’s monkeys in 15 groups in Lagwa and 193 monkeys in 20 groups in Akpugoeze. The Akpugoeze population was relatively stable over two decades, although the proportion of infants declined, and the number of groups increased. As Sclater’s monkey does not occur in any official protected areas, sacred populations are important to the species’ long-term conservation. Despite the monkeys’ destruction of human crops, most local people still adhere to the custom of not killing monkeys. These sites represent ideal locations in which to study the ecology of Sclater’s monkey and human-wildlife interactions.
Distribution of Mimosa diplotricha C. Wright nil invasive weed in relation to other herbaceous weeds in Agrarian ecosystems of Ibadan, Nigeria
(2017) Tanimola, O.O.; Awodoyen, R.O.; Olubode, O.S.
Mimosa diplotricha is an invasive weed whose spread can have negative impacts on plant biodiversity and agriculture.''In this study, a floristic survey was used to assess the distribution of Mimosa diplotricha in relation to other weed species in Ibadan, Nigeria. Florisiic survey was conducted using Jm x lin quadrat at 0.5 km intervals on transects along major roads of six purposively selected agrarian ureas based on prevalence oj Mimosa diplotricha, frdm Ibadan metropolis to: Alai jo, Akanran, lyana-Offa, Idi-Ayunre, hldo and Susa. The entire arpas are within 7° 14-7°30'N; 3°48'-4°04 E and altitude 127-261 in asl). The Relative Importance Values (RIV, %), relative density and relative, frequency, diversity indices {Species richness (S), Shannon-Wiener (11) and Evenness (J)} were determined. Eighty-six pHint species from twenty-eight families were enumerated. The RIV of Mimosa diplotricha was highest in all areas: 17.1 (Susa), 22.5 (Alcufo), 3L5 (Idi-Ayunre), 23.3 (lyana -Ojfa), 21.4 (Iddo), 36.0 (Akanran). While, the least RIV ranged from 0.31 (Luffa cylindrica; Sasa) to 0.97fCommelina erecta; Iddo). The Species richness (S), Shannon-Wiener (H) and Evenness (J) indices, in the areas were: 56.0, 3.1, 0.4 (Sasa); 31.0, 2.6, 0.4 (Alcufo); 44.0, 2.5, 0.3 (TdiAyunre); 40.0, 2.7, 0.4 (lyana Ojfa); 29.0, 2.6, 0.5 (Iddo) and 35.0, 2.0 and 0.2 (Akanran), respectively. The'high diversity indices revealed random distribution of species. However, high RIV values of Mimosa diplotricha in all surveyed axes showed that it is fast becoming the dominant weed species in Ibadan and may be a threat to
Diversity and floral composition changes in intensively cultivated practical year training program farm of the university of Ibadan, Nigeria
(2018) Jude, G.E.; Olubode, O.S.
Higher Institutions where agriculture is taught are required by National University Commission to have large areas of land for practical and demonstration activities. The lands are often cultivated intensively for decades under the same soil management practices, thus making them to become invaded with weeds which overtime become adapted to the ecosystem at the expense of soil productivity. The study was conducted to determine the species composition, invasiveness, spatial distribution of weed species and diversity of weeds on the site for Practical Year Training Programme (PYTP) of the Faculty of Agriculture, University of Ibadan in two consecutive years. The PYTP farm was floristically surveyed by using 21 plots of 150 m2 each and a strip of 5 m round was maintained for edge effects. Six (1 m2) square quadrats (126 in all) were randomly laid on each plot to enumerate the herbaceous flora of the farm. Flora composition, frequency and density values were evaluated for Relative Importance Values (RIV, %) following standard procedures. Soil of the farm was routinely analysed for its adequacy for agricultural purposes. A total of fifty two (52) plant species in seventeen (17) families were enumerated in the first year while a total of thirty (30) plant species belonging to fourteen (14) families were enumerated in the second year. In the first year, Tridax procumbens had the highest Relative Importance Value (11.73), distantly followed by Cynodon dactylon (6.44). Tridax procumbens was prevalent in plots not subjected to crop rotation. The abundance of plants was low on clay soils. Margalef index (12.81), Mehinick index (6.959), and Dominance (0.05262) indicated high overall species diversity, high species diversity in each plot, and low overall dominance respectively. In the second year, Gomphrena celosioides had the highest RIV (18.66) followed by Panicum maximum (12.43). Three soil types (sandy loam, loamy sand and clay) were identified. The soils were acidic (pH 4.7 – 4.8). Sandy loam and loamy sand soils had comparatively higher organic matter content than clay soil. The nitrogen concentration of the soils was generally low (0.6-1.33 g/kg). The Practical Year Training Programme land of the University of Ibadan is not productive and therefore should be allowed to rest for a long period of time. Conservation agricultural practices are recommended for the land anytime it is to be cultivated to deter further degradation.
Diversity and phytosocioiogy of herbaceous flora in the wetland area of the university of Ibadan integrated fish farm, Nigeria
(2014) Adegbite, K.S.; Olubode, O.S.; Awodoyin, R.Q.
University of Ibadan Integrated Fish Farm was assessed using stratified random survey of 108 randomly laid quadrats within 18 plots of900 m2 each. Floral identification, species diversity, relative importance value (RIV), ordination and classification analyses followed standard procedures. Presence of invasive plants were determined. Routine soil analyses conducted followed standard procedures. Soil data were analysed using ANOVA (P=0.05). Significantly different means were separated with least significant difference at p-0.05. The site contained 144 plant species distributed within 38 families. Species richness was high across all plots except plot two. Species dominance ranged from 0.03 to 0.1. RIV ranged from 0.15 to 6.3; Amaranthus viridis had the highest and Aspilia bussei, lowest. Multivariate analyses indicated two ecosystem structures comprising a small densely vegetated near-pristine wetland and a large sparsely vegetated perturbed area. Floral dichotomy included 12 positive preferential groups of 86 stands and 6 negative preferential groups of 22 stands. The soil was Silty-clay. Invasive plants species with high RIVs were Althernanthera brazilensis (1.33) and Bidens pilosa (0.15). pH (6.60), potassium (0.58), sodium (2.23), calcium (11.57), total carbon (38.04), total nitrogen (2.68), and phosphorus (50.63) were higher for soils collectedfrom under forest plots than in non-forested plots (5.85, 0.15, 0.16, 5.42, 5.1, 1.15 and 16.42 respectively). The vegetation of University of Ibadan Integrated Fish Farm was moderately high and stable. The wetland is not pristine, and prone to degradatior. Construction activities for aquacultural purposes should maintain the wetland for sustainable biological productivity. The flora should be assessed periodically.
Diversity and proximate composition of herbaceous components of old oyo national park, nigeria in relation to wildlife conservation
(2009) Olubode, O.S.; Awodqyin, R.O.; Ogunyemi, S.
The diversity of wildlife in Parks depends on availability and distribution of flora feeding resources. Abundance and proximate relationships between wild plants and wildlife may determine conservation potentials of a Park. The composition and diversity of species in three wetlands (Ibuya, Ipade-Aya and Ajalcu) in Old Oyo National Park, Nigeria were studied in dry (February-March) and wet (September- October) seasons of 2004-2006. Herbaceous flora of the three wetlands were systematically assessed using 5000 m2 plots on which two 100 m diagonal transects were superimposed to enumerate all low-growing plants that rooted within thirty randomly selected 1 m2 quadrats. Four most abundant plant species in two families were selected for proximate analyses. Three topsoil samples of each site were randomly collected and analysed for physicochemical properties. Hyparrhenia involucrata Stapf. and Andropogon tectorum Schumach were the most abundant herbs in the wetlands. Ipade-Aya had the highest Shannon-Weiner (H1) and evenness (J) values of 1.6 and 0.7 respectively. Ibuya had H'=1.0 and J=0.5; while Ajalcu had H'=1.0 and J=0.5. The protein contents of the forage grasses significantly (P<0.05) ranked in the order: Andropogon tectorum > Andropogon gay anus Kunth > Hyparrhenia involucrata > Hyparrhenia rufa (Nees) Stapf. Soils of the wetlands were mostly similar, except Ajalcu which was sandy loam. Fauna populations at the three sites were low. The highest detected faunal populations were nine at Ibuya, and three each at Ipade-Aya and Ajaku. Available nutritious grasses may not continue to sustain wildlife populations. Further research should consider increasing forage for faunal conservation.
Edaphic factors and soil organic carbon storage potentials under different land use types in omo biosphere reserves Nigeria
(2022) Oladoye, A.O.; Oyelowo, O.J.; Olubode, O.S.; Ojo, E.O.; Bakare, O.O.; Henry, C.A.
The regulatory functions of the soil are getting attention among scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. A study was carried out to investigate the SOC storage potentials under different land use types (Tectona grandis, Gmelina arborea, Acacia siamea, Pinus carrribea, and Natural forest) in Omo Biosphere Reserves Nigeria. The impact of the five important land use types on SOC and other soil properties were analyzed. Soil core samples were taken at two depths (0-10 and 10-30cm) to observe the changes in soil properties with depth. Laboratory analyses were carried out to determine the bulk density, soil pH, soil moisture, and soil organic carbon. The data obtained were analyzed using the Analysis of variance (ANOVA) and Duncan Multiple Range Test (DMRT) was used to separate the means while Principal Component Analysis (PCA) was used to examine the relationship between the soil parameters. Correlation analysis was carried out to examine if a relationship exists between soil depth and different land use on soil organic content and all other soil properties. The result showed that at both depths there is no significant difference between depths in pH, soil organic carbon, and soil moisture except for bulk density. Total Soil Organic Carbon stored in soil was highest in Teak plantation (3.1), followed by Acacia (2.17), and Natural forest (0.92), and at depth SOC was high in 0 10cm depth. The maximum value of bulk density (gcm3) was found high in 0-10cm at depth and was found high in Teak plantation (1.68) followed by Pinus plantation (1.67) and Acacia plantation (1.53). The distribution of moisture content showed no significant difference but the highest moisture was stored in Natural forest plantation (39.04), followed by Teak plantation (34) and Gmelina plantation (20), and the lowest in Pinus carribea plantation (10). Moisture content across depth showed that 0-10cm depth stored the highest but the 10-30cm depth () had the highest pH. Among the land use types, Teak plantation (5.84) had the highest pH, followed by Gmelina plantation (5.4) and Natural forest plantation (5.23). Results showed that SOC storage in soils can be influenced by different land use systems.
Edaphic factors and soil organic carbon storage potentials under different land use types in omo biosphere reserves Nigeria
(2022) Oladoye, A.O.; Oyelowo, O.J.; Olubode, O.S.; Ojo, E.O.; Bakare, O.O.; Henry, C.A.
The regulatory functions of the soil are getting attention among scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. A study was carried out to investigate the SOC storage potentials under different land use types (Tectona grandis, Gmelina arborea, Acacia siamea, Pinus carrribea, and Natural forest) in Omo Biosphere Reserves Nigeria. The impact of the five important land use types on SOC and other soil properties were analyzed. Soil core samples were taken at two depths (0-10 and 10-30cm) to observe the changes in soil properties with depth. Laboratory analyses were carried out to determine the bulk density, soil pH, soil moisture, and soil organic carbon. The data obtained were analyzed using the Analysis of variance (ANOVA) and Duncan Multiple Range Test (DMRT) was used to separate the means while Principal Component Analysis (PCA) was used to examine the relationship between the soil parameters. Correlation analysis was carried out to examine if a relationship exists between soil depth and different land use on soil organic content and all other soil properties. The result showed that at both depths there is no significant difference between depths in pH, soil organic carbon, and soil moisture except for bulk density. Total Soil Organic Carbon stored in soil was highest in Teak plantation (3.1), followed by Acacia (2.17), and Natural forest (0.92), and at depth SOC was high in 0 10cm depth. The maximum value of bulk density (gcm3) was found high in 0-10cm at depth and was found high in Teak plantation (1.68) followed by Pinus plantation (1.67) and Acacia plantation (1.53). The distribution of moisture content showed no significant difference but the highest moisture was stored in Natural forest plantation (39.04), followed by Teak plantation (34) and Gmelina plantation (20), and the lowest in Pinus carribea plantation (10). Moisture content across depth showed that 0-10cm depth stored the highest but the 10-30cm depth () had the highest pH. Among the land use types, Teak plantation (5.84) had the highest pH, followed by Gmelina plantation (5.4) and Natural forest plantation (5.23). Results showed that SOC storage in soils can be influenced by different land use systems.
Eutrophication of Dandaru reservoir in Ibadan, Nigeria in relation to land-use and mechanical desilting
(2016) Olubode, O.S.; Akpan, P. E.
Eutrophication of water bodies is mainly caused by influx of Nitrogen and phosphorus compounds from land-use. Understanding relationship water reservoirs and farmlands will foster management of ecological resources. This study examined the link between eutrophication and land-use at Dandaru reservoir at Agodi, Ibadan, Oyo State and effect (s) of mechanical clean up on the reservoir. The Vegetation, soil of Lawn (L), bush fallow (BF), vegetable farm (VF) and Agodi Gardens (AG), and water quality of Dandaru reservoir in Ibadan were systematically assessed pre- and post-desilting following standard procedures. Forty 0.25 m2 quadrats were floristically assessed for Relative importance values (RIV) and Shannon-Weiner index (H`). Three randomly extracted bulked and sub-sampled top soil of each land-use were analysed physiochemically. The reservoir was sampled for phosphate, Organic carbon (TON), nitrate (TN), dissolved oxygen (DO) and pH in three replicates at entry, mid and exit points of the river. Data were analysed using ANOVA at p=0.05. Means statistical differences followed Fisher’s LSD. Fifty one plant species were enumerated pre-desilting consisting of 15, 22, 29 and 11 species in L, BF, VF and AG respectively; 22 plants were enumerated post-silting consisting 10, 10, 8 and 8 species in L, BF, VF and AG respectively. legumes ranged in RIVs from 4.217-8.397 in BF and VF. Pre-desilting, VF had highest H` (3.334), while AG had lowest (1.988). Post-desilting, Lawn had highest H` (1.956) while VF had lowest (1.679). P, TOC, TN and pH were significantly different in all land-uses with TN (0.81±0.02g/kg) and TOC (7.83±0.05g/kg) in BF. Phosphorus (0.31±0.03g/kg) was high at AG pre-desilting. Post-desilting, TN (32.90±3.37g/kg) and TOC (2.24±0.04g/kg) were significantly high in lawn. Pre-silting, pH and DO were significantly different at all points, lowest at midpoint (6.73±0.04mg/l and 7.89±0.30mg/l respectively); post-silting, pH (7.87±0.00) and DO (9.54±0.0Img/l) increased at midpoint.The legumes in agricultural lands most likely contributed to eutrophication of Dandaru reservoir. However, desilting offered temporary restoration. Cessation of agricultural activities around Dandaru reservoir with its periodic assessment will prevent eutrophication
Fallow management potentials of sesbania pachycarpa dc.: the green manure effects on amaranthus cruentus l. in ibadan, south western nigeria
(2017) Egberongbe, K. R.; Awodoyin, R.O.; Olubode, O.S.
Sown fallow with nodulating legume shrubs has been identified as an alternative in improving soil fertility. The green manure potential of Sesbania pachycarpa on the performance of Amaranthus cruentus were studied in pot and field experiments in Ibadan, Nigeria. Sesbania pachycarpa seedlings were grown in pots for 0 (control), 15, 30, 45, 60 and 75 days, and on field for 0, 30, 45 and 60, before incorporating into the soil to assess the Green Manure (GM). Three weeks after incorporation, Amaranthus cruentus was grown on the soil for six weeks. The performance of A. cruentus was assessed with Plant Height (PH), Stem Diameter (SD) and Number of Leaves (NL). The pot and field experiments were CRD and RCBD, respectively with three replicates. Data were analysed using descriptive statistics and ANOVA at a0.05- In the pot trial, the performance of A. cruentus [PH (45.30±0.8 cm), SD (0.6±0.1 cm), NL (18±0.3)] were highest in 45-Day GM. The field results followed the same trend with PH (46.30+1.2 cm), SD (0.8+0.1 cm) and NL (19.3±0.7) of A. cruentus highest in 45-Day GM. Turning in the plant grown for a minimum of 45 days improved performance of Amaranthus cruentus.
Floristic importance of phyllanthus amarus schumach & thonn in selected farming communities and its domestication in Oyo state, Nigeria
(2019) Awodoyin, R.O.; Omage, F.I.; Egberongbe, R.K.; Olubode, O.S.
Phyllanthus amarus is a pantropic weed with numerous medicinal uses. It is collected in the wild, often in unwholesome environment and is hardly available all year round, which calls for its domestication for eventual cultivation. The distribution and seedling growth of P. amarus were studied in two seasons at two farming communities in Oyo State, Nigeria. A 25 x 25 m plot was marked out in Akufo and Fiditi. Fifteen quadrats (50 x 50 cm) were randomly placed using x-y ordinate system to enumerate and determine Relative Importance Value (RIV) for all low growing plants. Growth and dry matter accumulation of seedlings were monitored in a pot trial in clay and sandy-loam soils, combined with four watering intervals (1, 2, 3 and 7 days). Data were analysed using ANOVA and means separated by Least Significant Difference at 5% level of probability. Results showed that Phyllanthus amarus is more abundant at Fiditi (RIV=47.16%) than Akufo (RIV=9.15%) at the onset of wet season but reduced at the mid wet season. It performed best (P ≤ 0.05) on sandy-loam soil and daily watering significantly effected its best growth and dry matter yield. Phyllanthus amarus responded positively to daily watering, but its importance value reduced with recruitment of other species as the wet season advanced, which presented it as an inferior competitor and explains its reduced availability in the wild at the peak of wet season and in the dry season. For cultivation purposes therefore, Phyllanthus amarus should be grown in well-drained soils with regular weeding carried out and with adequate moisture provided.
Indigenous fruit trees of tropical africa: status, opportunity for development and biodiversity management
(2015) Awodoyin, O.R.; Olubode, O.S.; Ogbu ,U.J.; Balogun, B.R.; Nwawuisi, J.U.; Orji, K.O
Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have scarcely achieved the status of international recognition in commodity markets and research arena outside Africa. This paper presented a critical review of the status of IFT in the Tropical African sub-regions (of West Africa, Central Africa, East Africa, Southern Africa and the Indian Ocean Islands) in relation to the introduced naturalised fruit trees from tropical America and Asia, threats to the diversity and sustainable use of IFT, analysis of the opportunities and challenges of developing IFT, as well as targets for crop improvement of the rich IFT of Tropical Africa. Domestication programme via relevant vegetative propagation techniques for priority IFT of the sub-regions was examined and advocated, in addition to the adoption of complementary conservation strategies, including Field GeneBanks in the management of the continent’s IFT diversity.
Influence of weeding regimes on composition and diversity of weed species in upland rice (oryza sativa l.) field
(2017) Dada, O.A.; Oladiran, E.M.; Olubode, O.S.; Togun, A.O.
Abundance of weed species promotes biodiversity within agroecosystems whereas it constitutes biotic stress in arable farmland. There is insufficient information on effects of weed species composition and diversity’ on performance of upland rice in Nigeria. Therefore, a 2-year field study was conducted to assess the weed species composition, diversity and its effects on growth and yield of upland rice cultivars. A split-plot design was used with two rice cultivars (CGI4 and NERICA2) as the main plot treatment and four weeding regimes as the sub-plot. Weeds were sampled from each plot with a 0.5 m * 0.5 m wooden quadrat. The weed species were identified to species level, counted and recorded. Data collected were used to calculate relative frequency, relative density and relative importance value for each species. Dominance, Simpson, Shannon Wiener and evenness indices were used to describe the community structure. The flora of the study site varied widely in occurrence. Twenty four weed species comprising 16 annual herbs, four sedges, three grasses and one commelinaceae Family were found interfering with upland rice. The field had highly diversed annual, herbacious, dicotyledonous and monoc.tyledonous weed species native to tropical ecosystems. The upland rice field had evenly distributed rich and highly diversed weed community. Cultivar CGI4 performed significantly better than NERICA2 with respect to number of leaves (32.56) formed, tillering (8.67) and panicles (8.25) produced. The CG14 plot left unweeded throughout the study period had significantly highest weed biomass (6.16 t/ha) compared to NERICA2 plots. Absolute weed interefence reduced grain yield in NERICA2 and CGI4 cultivars by 42.7 % and 30.9 %, respectively. The biomass accumulated by weed species were inversely related to grain yield (t/ha) in both seasons.
On-field assessment of critical period of weed interference in okra [abelmoschus esculentus (l.) moench] field in ibadan, a rainforest-savanna transition eco-zone of Nigeria
(2009) Awodoyin ,R.O.; Olubode, O.S.
The critical period of weed interference is defined as the period in the life cycle of a crop during which it must be kept free of weeds to prevent unacceptable yield losses. The critical period of weed interference in okra [Abelmoschus esculentus (L.) Moench] was determined in the field trials during two cropping seasons (2006 and 2007) in the crop garden of the Department of Crop Protection and Environmental Biology, University of Ibadan, Ibadan located in the rainforest-savanna transition ecological zone of Nigeria. The study, consisting of two sets of treatments was carried out in a randomized complete block design with three replicates. In the first set of treatments, the crop was kept free of weeds for the first 2, 4, 6 and 8 weeks after planting (WAP) and subsequently weeds were allowed to grow (weed-free then weedy, WF-WD) until harvest, to determine the growth stage at which emerging weeds would no longer reduce the crop yields. In the second set of treatments, weeds were permitted to grow with the crop for an increasing length of time as listed above and subsequently the plots remained weed-free (weedy then weed-free, WD-WF) to determine the period at which weeds emerging with the crop began to suppress the growth of the crop and reduce its yield. Seasonlong weed-free (WD-0-WF) and weedy (WF-0-WD) treatments served as checks to compare weed competition and yield losses with other treatments. Season-long weed interference with okra resulted in 42.3% and 33.3% reduction in plant height, 54.9% and 45.5% reduction in stem diameter and 71.2% and 79.5% reduction in okra shoot dry weight in 2006 and 2007, respectively. Weeds that interfered with okra from 2 WAP resulted in 79.8% and 72.5% fresh fruit yield reduction in 2006 and 2007 respectively, and weed interference with okra from 8 WAP resulted in 19.8% and 19.6% yield losses in 2006 and 2007, respectively. Thirty one (31) weed species were enumerated in the study area with dicotyledons being the most prevalent (80.7%). The most important of the weed species among the dicotyledons was Synedrella
Performance of senecio biafrae (oliv. & hiern) j. moore under varying light intensities and compost rates in Ibadan, Southwestern Nigeria
(2019) Olubode, O.S.; Johnson, A.S.
Solanecio biafrae is an underutilized indigenous vegetable in southwest Nigeria. It is usually found in shades of other tree crops. This study investigated growth of S. biafrae as influenced by compost application under different light intensities in Ibadan, Southwest Nigeria. The pot study was conducted twice at the Crop Garden of the Department of Crop Protection and Environmental Biology, University of Ibadan. Four levels of light intensities were examined under multiple layers of nets: Growth under four test light intensities of unshaded natural light (0 net), and three levels of shades (1 net, 2 nets and 3 nets) assessed under four levels (0, 10, 15 and 20 g/pot) of compost (ratio 3:1 Tithonia-Poultry waste) in a randomized complete block design with light intensity as Blocks. Growth and yield data were analysed using analysis of variance and post-hoc tests conducted with Fisher's LSD at 5% probability. Lowest light intensity resulted in increased number of leaves, from 7.75 to 15.50 at 4 WAT and 7.78 to 18.50 at 6 WAT. Application of 20 g/pot compost resulted in higher number of leaves, number of nodes, vine height, vine diameter, root and shoot dry matter of S. biafrae under reduced light intensities. Low light intensity in combination with increased compost rates enhanced growth performance of S. biafrae. Cultivation of S. biafrae is recommended using of Tithonia diversifolia compost at the rate of 20g/5kg soil under low light intensity for optimum yield.
Response of vigna unguiculata.(L.) Walp. and amaranthus cruentus (L.) Thell to interference from acalypha segetalis mull arg. on marginal lands in southwestern Nigeria
(2001) Ogunyem, S.; Awodoyin, R. O; Osunkoya, O.O; Olubode, O.S.; Wewe, O.F.
The role of each weeds depends on weed type, density and duration of association with the crop as well as competitive ability of the crop. In open garden experiments, the phenology of Acalypha segetalis, a common weed of arable and ruderal habitats in south western Nigeria, and its influence on the growth and performance of Vigna unguiculata and Amaranthus cruentus, were investigated in 1999 and 2000. Acalypha segetalis was found to be slow growing in the first four weeks of its life cycle but developed rapidly and vigorously afterwords. It produced and shed seeds within 10 weeks of growth. Vigna unguiculata, which is highly susceptible to weed infestation in the first four weeks of growth, did not suffer significant growth and yield reductions from the association with j4 ca/yp/ia segetalis. However, Amaranthus cruentus, which has similar growth habits with the weed, suffered significant reductions in growth and yield. Amaranthus suffered up to 42% marketable yield loss when grown with Acalypha. The early slow growth of Acalypha determines its competitive potential in arable cropping systems. Crops that establish fast and with superior early growth ability may not suffer adverse competitive repression with the weed.