Abstract. This study investigated the ability of Penicillium sp. to bio-remediate spent engine oil contaminated soil both in vitro and in vivo. In the in vitro assay, mycelium of a seven day old culture of Penicillium sp. grown on Sabouraud Dextrose Agar (SDA) was punched out using a 0.5mm Cork borer and inoculated on the centre of Petri dishes containing the spent and unspent engine oil and incubated for seven days and daily reading of the mycelia growth obtained using a metre rule. For the in vivo assay, soil received 0 (control), 20/180, 40/360, 60/540, 80/720 and 100ml/900mm concentrations/treatments (inoculation with mycelium of Penicillium sp.). Seeds of Telfeira occidentalis was sown on the soil and assessed for growth performance (plant height, leaf area (using a metre rule) and leaf count (number of leaves) for 7, 14, 21 and 28 Days after Planting (DAP). Results of the in vitro assay showed a significant increase (p<0.05) in the growth diameter of Penicillium sp. relative to control. Results of the in vivo assay showed that spent engine oil had no significant effect (p<0.05) on the growth performance of T. occidentalis at 7, 14, 21 and 28 DAP and on fresh and dry weight (g) 28 DAP relative to control. After 28 days of plant growth, the added spent engine oil was no longer detected. The plant began producing pods 61 DAP. This study showed that Penicillium sp. can biodegrade hydrocarbons present in spent engine oil and as such is a good tool for bioremediation.

Gmelina arborea Roxb has important economic value in Nigeria and worldwide. It has been used as timber, for pulp and paper, furniture, plywood and for particle board. Due to the menace caused by fungal diseases in nurseries and sites where the seedlings are raised and the observed disease severity at the Awi Gmelina Forestry Project Nursery in Cross River State, Nigeria. It became necessary to provide a viable environmentally friendly measure to curb the diseases, hence, a trial on the antifungal effects of leaf extracts of Carica papaya and Azadirachta indica in-vitro using different extract solvents on some pathogenic fungi isolated from Gmelina arborea seedlings. The isolated fungi were Trichoderma viride (from stem and leaf) and Mucor mucedo (stem and leaf). The solvents used were ethanol, methanol, propanol, butanol, acetone, chloroform and distilled water. Phytochemical screening of extracts of C. papaya from the different solvents showed that there was no tannin and hydroxymethyl anthraquinine. Flavonoids and polyphenols were in excess in acetone and methanol extracts respectively. For A. indica, polyphenols were only found in excess in ethanol and methanol extracts. Application of the extracts at different percentages of 0% (control), 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% showed that Carica papaya extracted with butanol was more potent on Trichoderma viride and Mucor mucedo at 60%, 70%, 80% and 100% while the growth of Trichoderma viride and Mucor mucedo was checked by butanol extracts of A. indica at 70%, 80%, 90% and 100%. Conclusively, butanol extracts of C. papaya and A. indica at higher concentrations is recommended for use as spray to control the diseases.

Abstract. The inhibitory properties of the ethanolic and methanolic leaf extracts of Vernonia amygdalina and Cola acuminata on the fungal pathogens isolated from infected tomato fruits were investigated. The pathogens were Fusarium moniliformes and Rhizopus stolonifer. Various concentrations of the extracts ranging from 10,20,30, 40, 50, 60, 70, 80, 90 and 100% were separately added to PDA media. The fungal pathogens were separately inoculated into the media and incubated for seven days. Antifungal effects of these extracts on the mycelia growth of the pathogens were significant at P<0.05 for all treatments at higher concentrations. At 10-50% concentration, ethanolic and methanolic extracts of Vernonia amygdalina and Cola acuminata had no significant effect on the mycelia growth of Fusarium moniliformes and Rhizopus stolonifer after seven days observation period. At 60-100% concentrations, the two pathogens were completely inhibited by ethanolic extracts of Vernonia amygdalina and Cola acuminata. Methanolic extracts of Vernonia amygdalina and Cola acuminata inhibited completely Fusarium moniliformes and Rhizopus stolonifer at 80-100% concentrations. The in vitro inhibitory effects of these extracts at higher concentrations indicated that they can be used for the control of tomato fruit rot. It may be necessary to use them in prolonging the shelf-life of fresh tomato fruit and some other fruits.

Abstract. The phytochemical and antifungal efficacy of the ethanolic and methanolic stem bark and leaf extracts of Parkia biglobosa on the fungal pathogens isolated from infected green bean seeds obtained from the field in Akpabuyo, Cross River State, Nigeria were investigated in vitro. The pathogens were Botryodiplodia theobromae and Aspergillus niger. Various concentrations of the extracts ranging from 10g/100ml, 20g/100ml, 30g/100ml, 40g/100ml and 50g/100ml were separately added to PDA media. Results of the in vitro antifungal assay shows that at 40g/100ml and 50g/100ml concentrations, ethanolic stem bark and leaf extracts of P. biglobosa completely inhibited the radial growth of B. theobromae and A. niger after seven days observation period while those of methanolic extracts completely inhibited the redial growth of the fungal pathogens at 50g/100ml concentration. Results, however, shows that the extracts had a significant effect (P<0.05) on the radial growth of the fungal pathogens at all the different concentrations tested as compared with the control. Pathogen growth inhibition was most effective at 30g/100ml, 40g/100ml and 50g/100ml concentrations. The inhibitory action of the extracts increased/decreased with a corresponding increase/decrease in the concentration of the plant extracts. Ethanolic stem bark and leaf extracts of P. biglobosa was found to be more effective in inhibiting the redial growth of the fungal pathogens than those of methanolic extracts, also ethanolic and methanolic stem bark extracts were observed to be more effective in the inhibition of the radial growth of the fungal pathogens than leaf extracts. Phytochemical screening of the extracts revealed the presence of cardiac glycosides, reducing sugars, flavonoids, saponnins and tannins with traces of alkaloids in stem bark extracts while flavonoids, alkaloids, cardiac glycosides, saponnins, tannins and terpenoids were present in leaf extracts.

The inhibitory properties of the ethanolic and methanolic leaf extracts of Vernoniaamygdalina and Colaacuminata on the fungal pathogens isolated from infected tomato fruits were investigated. The pathogens were Fusariummoniliformes and Rhizopusstolonifer. Various concentrations of the extracts ranging from 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100% were separately added to PDA media. The fungal pathogens were separately inoculated into the media and incubated for seven days. Antifungal effects of these extracts on the mycelia growth of the pathogens were significant at P<0.05 for all treatments at higher concentrations. At 10-50% concentration, ethanolic and methanolic extracts of Vernoniaamygdalina and Cola acuminata had no significant effect on the mycelia growth of Fusariummoniliformes and Rhizopusstolonifer after seven days observation period. At 60-100% concentrations, the two pathogens were completely inhibited by ethanolic extracts of Vernoniaamygdalina and Cola acuminata. Methanolic extracts of Vernoniaamygdalina and Cola acuminata inhibited completely Fusariummoniliformes and Rhizopusstolonifer at 80-100% concentrations. The in vitro inhibitory effects of these extracts at higher concentrations indicated that they can be used for the control of tomato fruit rot. It may be necessary to use them in prolonging the shelf-life of fresh tomato fruit and some other fruits.