The utilisation of herbicides by indigenous microorganisms obtained from Ago-Iwoye, Nigeria, for enhanced growth rates and as carbon source in-vitro

Abstract

This study determined the abilities of indigenous microorganisms to utilise atrazine, xtravest,gramoxone and glyphosate as a carbon source and for their growth. Isolation ofmicroorganisms was done using the spread plate method on the solid mineral salts mediumwith each herbicide added to separate plates. The plates were incubated at 30°C for 5 days forbacteria and at 30oC for 7days for fungi. B. subtilis, P. aeruginosa, P. florescences, P. putida,Aspergillus niger, A. tamarii, Fusarium oxysporum, and P. chrysogenum were isolated in allthe herbicide treated soils. Bacillus subtilis recorded the highest optical density value of 1.401(logCFU/ml) on the 25th day and viable count value of 9.08 (log CFU/ml) (1.21×109 cfu/ml)on the 20th day during growth on glyphosate. F. oxysporum recorded the lowest pH of 4 ingramoxone on the 25th day of incubation and the highest count of 6.10×104 cfu/g on the 20thday during atrazine utilisation. B. subtilis, A. niger and F. oxysporum showed the best abilitiesto utilise the herbicides for growth and as carbon source. Indigenous microorganisms used inthis study successfully utilised the herbicides as carbon source and for growth hence they couldbe used in bioremediation.