Browsing by Author "Adedire, O. M."

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Antifungal potential of endophytic Bacillus species isolated from tomato (Solanum lycopersicum) against Fusarium oxysporum collected from selected farms in Nigeria
(Taylor and Francis, 2023) Adedire, O. M.; Aduramigba-Modupe, A. O.; Odeniyi, A. O.
Fusarium wilt, caused by Fusarium oxysporum, is a prevalent and destructive disease of tomato (Solanum lycopersicum L.) in Nigeria. The development of safe and efficient biocontrol measures is important for the management of the disease. In this study, the incidence of Fusarium wilt of tomato in four agricultural zones of Oyo State was established through purposive sampling, and the abundance and in vitro biocontrol potential of Bacillus endophytes were determined. Strains of Fusarium oxysporum and Bacillus endophytes were isolated from tomato plants collected from 21 farms. The in vitro inhibition potential of endophytes was determined through a modified dual-culture assay involving six endophytes and carbendazim (fungicide), arranged in a completely randomized design. Using a disease rating scale of 0–9, the highest wilt severity (6.67) and incidence (39.30%) were observed on Akinware Farm in the Ibadan/Ibarapa agricultural zone of Oyo State. Fusarium oxysporum IB3q caused severe wilt symptoms, including leaf chlorosis, necrosis, vascular discoloration and wilting, on infected Alausa and Ibadan-local tomato varieties. Thirty-nine strains of Bacillus endophytes were isolated from the tissues of healthy tomato plants. Six of the isolated Bacillus endophytes inhibited Fusarium oxysporum. Bacillus amyloliquefaciens Sa08 and Bacillus subtilis Og04 produced inhibition zones of 15.67 mm and 19.43 mm, respectively, against Fusarium oxysporum and caused hyphal disintegration of the pathogen. These isolates produced cell wall-degrading enzymes with relative activities ranging from 0.87 to 5.04. Based on their in vitro inhibitory potential, Bacillus amyloliquefaciens Sa08 and Bacillus subtilis Og04 should be considered as prospective biocontrol agents against seed-borne Fusarium pathogens and Fusarium wilt of tomato.
Effects of dichlorvos (DDV P) on the haematological properties of wistar rats
(2015) Olaoye, S. O; Fadina, O.O; Fayinminnu, O. O.; Adedire, O. M.; Ogundipe, W. F; Fajobi, A. K.; Farinu, A. O
The potential sub-chronic toxicological effects of oral administration of Dichlorvos (DDVP) on wistar rats was investigated for a period of 6 weeks. Thirty-two (32) wistar rats (equal number of both sexes) were uniformly divided into two groups while each comprised of 4 divisions with four rats each, At the end of experiment, animals were sacrificed and heamatogical test was carried out to investigate the possible toxicological effects of the oral administration of the pesticide on the rats. Results generally showed a dose-pendant response with PCV, Kb, RBC and Plan values that are significantly different from each (P<0.05) among the male rats while PCV and RBC values are significantly different from each other (P<0.05) while all other heamatological parameters in both sexes showed no significantly difference from each other at P<0.05. This result suggests that ingestion of the pesticides (Dichlorvos) may not be toxic at the doses investigated
Effects of Dichlorvos (DDVP) on the Haematology properties of Wistar rats
(Delta State University, 2015) Olaoye, S. O.; Fadina, O. O.; Fayinminnu, O. O.; Adedire, O. M.; Ogundipe, W. F.; Fajobi, A. K.; Farinu, A. O.
The potential sub-chronic toxicological effects of oral administration of Dichlorvos (DDVP) on wistar rats was investigated for a period of 6 weeks. Thirty-two (32) wistar rats (equal number of both sexes) were uniformly divided into two groups while each group comprised of 4 divisions with four rats each. At the end of experiment, animals were sacrificed and haematological test was carried out to investigate the possible toxicological effects of the oral administration of the pesticide on the rats. Results generally showed a dose- dependent response with PCV, Hb. RBC and Plat values that are significantly different from each other (P<0.05) among the male rats while PCV and RBC values are significantly different from each other (P<0.05) while all other haematological parameters in both sexes showed no significant difference from each other at P<0.05. This result suggests that ingestion of the pesticide (Dichlorvos) may not be toxic at the doses investigated.
Management of Fusarium wilt disease of tomato (Solanum lycopersicum L.) using selected plant extracts
(Conscientia Beam, 2021) Aduramigba-Modupe, A. O.; Alawiye, T. T.; Adedire, O. M.
Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder and Hansen, is considered the most widespread, prevalent and economically damaging fungal disease of tomato in Nigeria. This study was conducted to isolate and identify fungal pathogens associated with tomato wilt disease, and to evaluate the efficacy of four plant extracts in the management of wilt disease in vitro and in vivo. Two tomato varieties, Roma VF and UC 80, were used for the biocontrol assay. Four plant extracts, Zanthoxylum zanthoxyloides roots, Distemonanthus benthamianus stems, Azadirachta indica seeds and Oryza sativa husk, were evaluated against Fusarium oxysporum f. sp. lycopersici. Three concentrations (0.03, 0.04 and 0.05 g/mL) of each extract were investigated using the agar dilution method for radial growth inhibition assay. Of the four plant extracts evaluated, Oryza sativa husk extract was the most effective in inhibiting the growth of Fusarium oxysporum, both in vitro and in vivo. Rice husk extract (0.05 g/mL) had the highest inhibition rate (100%), followed by Azadirachta indica extract (80.32%) at 0.05 g/mL concentration, while Zanthoxylum zanthoxyloides and Distemonanthus benthamianus had inhibition rates of 71.83% and 61.41%, respectively, at 0.04 g/mL. Tomato plants treated with rice husk extract (0.05 g/mL) had the lowest wilt severity scores of 1.25 and 1.50 for UC 80 and Roma VF varieties, respectively. Rice husk extract was the most effective treatment against Fusarium wilt in both tomato varieties and could serve as an alternative to synthetic chemicals in controlling Fusarium oxysporum f. sp. lycopersici.
Seed-borne fungi and seedling performance of Provitamin A Maize (Zea mays L.) stored in different packaging materials and temperatures
(Faculty of Agriculture and Forestry, University of Ibadan, 2023) Aduramigba-Modupe, A. O.; Adedire, O. M.; Fashola, O. O.; Adeoya, O.
Maize (Zea mays L.) is widely cultivated across most agro-ecological zones in Nigeria. However, fungi are commonly associated with maize from the field through storage, reducing the economic value and viability of stored grains. Effective control of post-harvest storage fungi is therefore essential. This study evaluated the effects of cold storage (0–5°C) and room-temperature storage (25 ± 5°C) of maize grains preserved in plastic containers, aluminium packs and tin silos over a 120-day storage period on seedling characteristics and fungal occurrence. Three provitamin A maize varieties, PVA SYN2, PVA SYN6 and PVA SYN8, were used in the experiment. Data were collected on fungal incidence, germination percentage, root length and shoot length. Fungal species were isolated on Potato Dextrose Agar (PDA) and identified using standard procedures. The fungi identified from the stored maize varieties were Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Rhizopus stolonifer and Curvularia lunata. In general, Rhizopus stolonifer (50.00%), Curvularia lunata (46.67%) and Aspergillus fumigatus (40.00%) had the highest frequencies of occurrence in the provitamin A maize varieties. Although storage temperature, storage materials and fungal contamination did not significantly affect germination percentage of the three provitamin A maize varieties, seedling performance, as measured by shoot and root lengths, varied significantly among treatments. The most effective storage conditions for minimizing fungal contamination were preservation in tin silos and aluminium packages under low-temperature conditions. The study therefore recommends storing provitamin A maize grains in tin silos or aluminium packs at low temperatures to reduce fungal contamination and enhance seedling growth performance during storage.
The effect of Rhizophere Bacterial Consortium on the Manifestation of Tobamoviral Infection Symptoms on Tomato
(SCIENCEDOMAIN international, 2018) Adedire, O. M.; Aduramigba-Modupe, A. O.; Olaoye, S. O.; Ogundipe, W.F.; Farinu, A. O.
Contrary to available reports on the prevalence of microbial diseases of tomato in Nigeria, the emergence of mosaic viral disease on tomato farms is gradually becoming a very significant additional threat to the production of this economically important vegetable crop. In addition, the resistance of Tobamoviral diseases to chemical control measures makes them particularly difficult to control once established. Unlocking the specificity of the rhizosphere microbiome towards the general health and performance of tomato is key to achieving a safer means of combating microbial diseases of tomato. In this study, the predominant rhizosphere bacteria associated with healthy and infected tomato were compared, and the effect of tomato seed treatment with a selected rhizobacterial consortium on the incidence of Tobamoviral infection symptoms was determined. Bacillus thuringiensis, Pseudomonas aeruginosa, Bacillus subtilis, Bacillus macerans and Bacillus cereus were isolated from the rhizosphere of healthy tomato plants using the pour plate isolation method, while Pseudomonas aeruginosa and Bacillus subtilis were not isolated from rhizosphere samples associated with infected tomato. Tomato seeds were treated with the predominant rhizobacterial consortium isolated from healthy tomato plants, while seedlings were mechanically inoculated with triturated tissue extracts from infected plants. Significant reduction in the incidence of Tobamoviral disease symptoms was recorded on tomato plants grown from treated seeds. Additional (new) Tobamoviral disease symptoms were not recorded at the second, fifth and sixth weeks after transmission of the pathogen in treated plants, while disease incidence values of 23.83%, 3.03% and 3.33% were recorded on untreated plants, respectively. Average growth performance measures, including fruit count, fruit weight, stem girth and number of flower clusters per plant at 16.76, 43.80 g, 0.93 cm and 9.67, respectively, were significantly higher in treated tomato plants than in plants grown without the seed treatment. Consequently, it could be inferred that the healthy tomato-associated rhizosphere bacterial consortium used in this study influenced the resistance of mechanically inoculated tomato plants to the manifestation of Tobamoviral infection symptoms and improved the overall performance of the plant.