scholarly works in Crop Protection & Environmental Biology
Permanent URI for this collectionhttps://repository.ui.edu.ng/handle/123456789/491
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Item Physiological responses of cowpea simultaneously exposed to water deficit stress and varying light intensities at vegetative and reproductive growth stages(Update Publishing House, 2022) Adeniyi, O. I.; Adejumo, S. A.; Fofana, M.; Adegbehingbe, F. T.A combination of stresses as it occurs on the field poses more challenges to crop production than individual stress. Crops’ response to single stress also differs from that of combined stresses. The morpho-physiological responses of two cowpea varieties (IT89KD-288 and IT99K573-1-1) to a combination of stresses (water deficit stress and high light intensity) were investigated at different growth stages. Three levels of light intensities (L3: 259 Lux- 36%, L2: 394 Lux-55% and L1: 710.2 Lux-100%) were imposed using one, two and zero layer(s) of the net, respectively, while, water deficit stress at four levels (W1: no water stress; 0-5 bars, W2: moderate water stress; 5-15 bars, W3: moderately-severe; 15-40 bars and W4: severe water stress; 40-70 bars) was imposed differently at vegetative and reproductive growth stages. Data were collected on the cowpea yield, Leaf Temperature (LT), Chlorophyll (C), Photosynthesis (P), Stomatal Conductance (SC) and Canopy Transpiration Rate (CTR). Exposure to W4 under L1 considerably reduced cowpea yield by 80% compared to those grown under L3 and full watering. Reduced light intensity enhanced cowpea grain yield irrespective of water deficit stress and IT89KD-288 was superior to IT99K573-1-1. Reduction in light intensity also increased the SC from 55.18 in L1 to 76.88 in 36 % L3. Full light intensity without water stress (100% light intensity), increased C content, while severe water stress reduced the C content and CTR. Photosynthesis was, however, reduced under low light intensity compared to 100% light intensity. It was also observed that water deficit stress imposed at the reproductive stage did not affect P, CTR and SC unlike that of the vegetative stage. In conclusion, reduced light intensity enhanced cowpea tolerance to water deficit and increased yield. Cowpea response was dependent on growth stage, variety and severity of stress.Item Pre‑sowing seed treatment with proline, glycine betaine, and soil amendment with compost as strategies for improving yield and drought tolerance in cowpea(Springer Nature, 2022) Akinmolayan, T. V.; Adejumo, S. A.Purpose Drought is one of the major abiotic stresses limiting crop production. Compatible solutes, like proline (P) and glycine betaine (GB) enhance crop tolerance to abiotic stresses. Compost also supplies nutrients to crop and enhances crop tolerance to stress. The effects of pre-sowing seed treatments with P and GB as well as soil amendment with compost on cowpea performance under water deficit stress were investigated in this study. Methodology Cowpea seeds were soaked in P and GB at 0 (distilled water: control), 2.5, 5, and 10 mM for 12 h before sowing. Compost (C) was applied at 2.5, 5, and 7.5 t ha− 1. Water stress was imposed by withdrawing water for 10 (W1) or 20 (W2) days, at vegetative (VS) or reproductive (RS) stages. Data were collected on cowpea growth parameters, yield, nodulation, P, and GB accumulation. Results The W2 at VS reduced cowpea growth and yield by 100% compared to the unstressed plants, while, W1was more tolerable. Proline, GB and C enhanced tolerance, growth, and pod yield, especially with C5 t ha −1, C7.5 t ha −1, GB5mM, and P2.5 mM. Water stress increased P and GB in untreated plants more than the treated plants. Compost at every rate, reduced the accumulation of proline and GB in cowpea under stress (W1), whereas proline was more in plants pre-treated with GB10mM and P2.5 mM under W2 at VS compared to RS. At RS, compost increased P and GB accumulation and these were reduced in P treatments. Conclusion Compost and seed treatment with solutes enhanced cowpea stress tolerance and improved yield.Item Efficacy of three botanicals in cowpea field, Oyo state, Nigeria(2020) Isienyi N.C.; Fadina O.O.; Fayinminnu O.O.; Olubode O.S.Aims: To evaluate the effects of different concentrations of the plant extracts of Eucalyptus camaldulensis (EU), Eucalyptus torreliana (ET) and Leucaena leucocephala (LL) on seedgermination, seedling-growth, weed flora and yield performance of cowpea. Study Design: The study was laid out in a completely randomized design (CRD) with eighteen ttreatments replicated three (3) times, totaling fifty-four (54) experimental samples. The whole experiments were repeated in two trials. Place and Duration of the Study: This study was carried out on the roof top garden of department of Crop Protection and Environmental Biology, University of Ibadan, Nigeria from 2015 to 2017. Methodology: Leaves of EU, ET and LL were harvested, air-dried, milled and assayed for phytochemicals (mg/g) following standard-procedures. Milled samples (144, 108, 72, 36 and 0 g) of each botanical were dissolved in 1 L distilled-water to obtain Aqueous-Leaf-Extracts (ALE) of 100, 75, 50, 25 and 0% (control) concentrations. Ten seeds of cowpea-Ife brown in petri dishes were treated with the different concentrations. Data were collected on Seed Germination-SG (%). In pots containing 10 kg soil, cowpea-seeds (2 plants/pot) were sown. Each botanical-extract at different concentrations and paraquat (5 mL/L/ha) were applied, before and five Weeks-After-Sowing (WAS). Data were collected on Plant height-PH (cm) at 3,5,7,9 and 11 WAS, while Grain Yield-GY (g/pot) was determined at maturity. Relative Importance Values (RIVs) were determined following standardprocedures. Data were analysed with descriptive-statistics and ANOVA at α0.05. Results: Total phenols (32.04±0.10), tannins (27.40±0.04) and saponins (20.15±0.03) were significantly higher in EU than in ET and LL. Cowpea SG ranged from 80.0±0.5 (50% LL) to 100.0±1.2 (100% LL). Cowpea PH ranged from 18.2±2.0 (100% ET) to 48.5±3.2 (100% EU) both at 9-WAS. Cowpea GY ranged from 0.1±0.1 (25% LL) to 4.2±0.5 (50% LL). Mitracarpus villosus had highest RIV of 52.3 (100% EU at 3-WAS) but reduced to 28.5 (100% EU at 9-WAS). Aqueous-leafextract of Eucalyptus camaldulensis at 100% reduced Mitracarpus villosus populations, while Leucaena leucocephala at 50% improved grain yields.Item 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.Item Comparative assessment of three sources of crude cassava water extract as bio-herbicide(2013) Fayinminu, O. O.; Fadina, O.O; Olabiyi, T. ITwo experiments were conducted at Owode- Ijako in Ogun State, Nigeria between September 2006 and April 2007 to investigate the efficacy of three sources of Crude Cassava Water Extract (CCWE) as post emergence herbicide on weeds of cowpea. The trials were arranged in randomized complete block design and replicated three times. The treatments were 25% and 50% of Bulk sample, MS6 and TMS extracts respectively, and two controls; unweeded and handweeded in each trial. Herbicidal efficacies of CCWE in controlling cowpea weeds were evaluated using phytotoxicity, weed biomass and density. The results showed that spraying CCWE of Bulk and MS6 at 50% on cowpea weed caused 40 and 50% phytotoxicity respectively. There was no significant difference in weed biomass (65.3% and 74.5%) and weed density (79.92 and 80.33) of CCWE of bulk sample and MS6 respectively. Whereas handweeded achieved 98.68% and 96.65% weed biomass and density respectively. The growth attributes such as plant height, number of leaves and leaf area differed significantly due to different treatments. Grain yield and yield components of cowpea were significantly influenced by the application of CCWE from the three sources. Highest grain yield (540kg/ha) was recorded in handweeded plots but was comparable to plots sprayed with 50% CCWE of bulk samples (450kg/ha) and MS6 (430kg/ha) while least grain yield was recorded in unweeded plots.Item Reduced Morphological Root Features of Anthracnose Infected Cowpeas (Vigna unguiculata (I.) Walp)(2002) Ajari, I. O.; Fadina, O.Oln a green house experiment to determine the effects of anthracnose disease caused by collectricum lindemuthianum on cowpea, sterilized siols in planting pots were used for planning two susceptible cowpea varieties (Ife Brown and 1782-60). The seedlings were inoculated with the inoculum meal of the pathogen after 3 weeks of planting. The results obtained show that characteristics tan to brown anthracnose symptoms had appeared on the leaves of both varieties after 3 weeks of inoculation, while the roots of the infected cowpeas were observed to be morphologically different from the roots of the uninfected plants. Similarly, infected plants were smaller in size and a marked reduction in their yield IT82f 60 (35%) versus Ife Brown (19%). The reduction of the plant structures and yield of the infected plants was suspected to have been as a result of the anthracnose diseaseItem The Antifungal and nematicidal potentials of vernonia amygdalina on cowpea (vigna unguiculata (l.) walp)(2013) Onoja, C.U; Fadina, O.OVernonia amygdalina is a herbaceous plant that grows in the wild and is widely cultivated as food crop in sub-Saharan Africa. The study evaluated its fungicidal and nematicidal Potentials. Isolates of Macrophomina phaseolina were obtained from germinating cowpea variety IT845-2246-4 growing on natural infested soil at screen house in International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria (70 261 N, 50 541 E) and then subcultured to achieve pure culture, while inculum of the root knot nematode, Meloidogyne sp. was obtained from infested Celosia sp. plants through Standard pathological and hematological procedures. Aqueous and ethanol extracts of V. amygdalina at various concentrations of 2.5%, 5% and 10% were prepared and tested in-vitro against Macrophomina phaseolina and the root knot nematode Meloidogyne sp. At incubation of 27.50C-30C for 7-days, radial growth of the plated M. phaseolina was measured at 24-hour intervals and percentage fungitoxicity calculated, while Meloidogyne sp. egg hatch and Td juvenile stage mortality were observed at 24-hour intervals for a 10- day period. Fungitoxicity tests showed aqueous extracts of 5% and 10% concentration significant/y inhibited mycelia growth (32.08% and 34.77%, respectively) when compared with the control Ethanol extracts exhibited 100% fungicidal activity. Furthermore, egg hatch by Meloidogyne sp. was completely inhibited by both extracts preparation at 2.5% and 5% concentrations while 100% mortality of Meloidogyne sp. juveniles was observed on the fifth day post-treatment. Vernonia amygdalina was identified as a natural, readily available and cheap source of fungicide and nematicide. It is recommended for control of charcoal rot infection and Meloidogyne sp. infestation of cowpea.Item Screening of cowpea varieties for resistance to brown blotch fungal disease(2006) Ajibade, S. R.; Owolade, O. F.; Balogun, M. O.; Fadare, T. A.Seventy-one cowpea varieties were screened in the field out of which nine resistant varieties were selected and these were further evaluated for resistance to cowpea brown blotch disease caused by Collectorichnm capsicl under artificial inoculation. The results showed that the cowpea variety IT95k- 193-12 appeared to be the most resistant to brown blotch disease. Artificial inoculation seemed to be more effective in identifying resistant genotypes as most of the cowpea varieties with moderate resistance in the field were highly susceptible under artificial inoculation.