Abstract Detail

Ecology/Pathology

Adongbede, Erute Magdalene [1], Akinyeke, Oluwanifemi [1].

A study of the degradative potential of moulds isolated from the rhizosphere of three weeds (Commelina diffusa, Aspilia africana and Vernonia cinerea).

This study investigates the use of fungi in the root zones of weeds in Lagos for biodegradation purposes. The three  weeds are Aspilia africana, Commelina diffusa and Vernonia cinerea. The fungi isolated from the root zones of these weeds include Aspergillus fumigatus, Penicillium brevicompactum, Aspergillus niger (black and yellow variety) Penicillium citrinum, Aspergillus niger (white and black variety) and Trichoderma viride. These fungi were grown on separate media contaminated with crude and diesel fuel at different levels of contamination (5 and 10%) and non contaminated medium. Extraction of residual hydrocarbon was performed after growth of these fungi on the contaminated medium and weight of residual hydrocarbon compared with control; this was used to calculate percentage degradation. A. fumigatus isolated from Aspilia africana grew at both levels of contamination in crude oil and diesel contamination. Inhibition increased with increasing levels of contamination. P. brevicompactum isolated from Aspilia africana grew at both levels of contamination in diesel and crude oil contaminated media and growth gradually superseded that of the control media. This also occurred in P. citrinum (isolated from V. cinerea) as there was no inhibition of growth by the contaminant at both levels of contamination. A. niger (black and yellow variety, isolated from V. cinerea) grew at both levels of contamination in diesel fuel and crude oil contaminated media but growth was slightly reduced at 10%. The inhibition of the growth of Trichodrema viride (isolated from Commelina diffusa) by diesel fuel and crude oil was low at both level of contamination. Diesel fuel had a stimulating effect on the mycelia growth A. niger (white and black variety, isolated from C. diffusa) at 10% level of contamination. The fungus grew at both level of contamination in crude oil contaminated media with little or no inhibition. The highest percentage degradation of crude oil was seen in P. citrinum and P. brevicompactum at 10% (78%) while the lowest percentage degradation of crude oil was seen in A. fumigatus at 5% crude oil (48.5%). P. citrinum showed the highest percentage degradation (73.2%) of diesel at 10% level of contamination. This suggest that A. africana and V. cinerea are the best weeds to be considered for phytoremediation/rhizoremediation because P. brevicompactum and P. citrinum which degraded the contaminants best were found to be associated with the root zone of these weeds respectively.

1 - University of Lagos, Botany, University Road, Akoka, Yaba, Lagos, Lagos, 11011, Nigeria

Keywords:
Rhizosphere
Phytoremediation
Petroleum hydrocarbons
Percentage inhibition
Percentage degradation.

Presentation Type: Offered Paper - Paper
Session: 16
Location: Room 104 AB/Kellogg Hotel and Conference Center
Date: Wednesday, June 11th, 2014
Time: 11:15 AM
Number: 16004
Abstract ID:40
Candidate for Awards:None