Crop Protection & Environmental Biology

Permanent URI for this communityhttps://repository.ui.edu.ng/handle/123456789/490

Browse

Author: search.filters.author.Awodoyin, R.O.Start date: 2020

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Floristic composition, diversity and community structure in a secondary rainforest in Ibadan, Nigeria
    (2021) Seyni, B.M.; Awodoyin, R.O.; Olubode, O.S.; Adeniji, S.A.; Ibrahima, D.B.
    Secondary forests may act as buffer area and serve as reservoir for biotic components that are lost from primary forest due to anthropogenic disturbances. This study investigated the floristic composition, diversity and community structure of Cocoa Research Institute of Nigeria (CRIN), Idi-Ayunre, Ibadan, Nigeria. Twenty-five main plots (each 50 m × 50 m) were randomly mapped out to enumerate tree species, five 10 m × 10 m sub-plots were systematically mapped out within each main plot to enumerate shrubs and three quadrats (1 m × 1 m) were laid in each sub-plot to enumerate herbaceous species in Wet Season (WS) and Dry Season (DS). Relative Importance Value (RIV), Taxa, Individuals, Dominance, Shannon-Wiener, Equitability and Jaccard similarity index were determined. A total of 181 plant species from 145 genera and 54 families which included 63 trees, 33 shrubs and 85 herbaceous species were enumerated. In wet season, Triplochiton scleroxylon, Lonchocarpus griffonianus and Chromolaena odorata had the highest RIV while in dry season, Terminalia superba, Lonchocarpus cyanescens and C. odorata were the highest for trees, shrubs and herbs, respectively. Low dominance but high equitability and Shannon-Weiner values indicated inter-specificity among trees, shrubs and herbs. It was only in herbs that Jaccard-similarity was less than 100% across seasons. Resilience for keystone species conservation is possible due to flora species heterogeneity of the study site.
  • Thumbnail Image
    Item
    Assessment of soil seed banks in relation to aboveground vegetation in three ecosystems within university of ibadan, Ibadan, South Western Nigeria
    (2020) Afolabi, A.S.; Egberongbe, R.K.; Awodoyin, R.O.; Olubode, O.S.
    Succession after disturbance. In the assessment of natural re-vegetation capacity of some ecosystems within the University of Ibadan, Nigeria, SSB contents were assessed and compared with the above-ground vegetation (AGV). Three ecosystems (Arable, Fallow and Plantation) were selected, with 25 x 25 m area marked out in each for random sampling, using XY-ordinate technique. Ten points were located for placement of wooden quadrat (50 x 50 cm). All plant species that rooted within each quadrat were enumerated. Soil samples were collected at 0-15 cm depth at the centre of each quadrat and bulked by site. One kilogram soil, replicated 12 times in each site, was monitored for seedling emergence for five months. Species richness (R), Shannon-Wiener index (H') and Jaccard Similarity Index (J) were determined for AGV and SSB. Plant family Poaceae dominated AGV while Amaranthaceae dominated SSB in all ecosystems. The R in AGV and SSB ranged from 14-24 and 6-15 respectively. The H' in AGV were close (2.27-2.69) but ranged from 0.84 (plantation) to 2.27 (arable) in SSB. The J for SSB/AGV were 33.3%, 14.3% and 5.9% in arable, fallow and plantation ecosystem respectively, indicating the highest species resemblance in the most disturbed arable ecosystem.
  • Thumbnail Image
    Item
    Allelopathic effect of pentaclethra macrophylla benth. leaf extracts on germination and seedling growth of maize and okra
    (2020) Ogbu, J.U.; Awodoyin, R.O.; Olubode, O.S.
    Pentaclethra macrophylla Benth. is an indigenous leguminous tree of southern Nigeria's agroecosystems, whose seeds are used as spices; however, its allelopathy potential is not understood. Therefore, this study was aimed at investigating P. macrophylla allelopathic effects on germination and seedling growth of maize and okra. Materials and Methods: Allelopathic effects of Aqueous Leaf Extracts (ALE) of P. macrophylla at 0 (control), 10, 20, 40 and 80% concentrations on maize (n = 200) and okra (n = 200) seed germination and seedling growth were assessed in laboratory and screen house nursery. Total germination (%) for both crops was determined at one Week After Sowing (WAS); while Number of Leaves (NL), Plant Height(PH) (cm), Root Length (RL) (cm) and Dry Weight (DW) (g) were evaluated at 8 WAS. Experimental design used in the study was completely randomized design. Data were analyzed using descriptive statistics and ANOVA at a0.05. Results: Above 90.0% germination was recorded for maize in all the ALE concentrations, while for okra ALE-10 gave significantly highest germination (90.0±8.7%) and ALE-80 gave least (42.5±26.3%). Maize and okra seedlings given ALE-40 had highest NL, PH and DW;* while ALE-0 (control) had least values in PH and DW, respectively. Control had highest RL in both crops. The ALE-10 gave least RL in maize and ALE-20 gave least RL in okra. Conclusion: Pentaclethra macrophylla aqueous leaf extract at 10% enhanced germination, while 40% concentration encouraged dry matter accumulation and height in maize and okra seedlings.