Selective isolation and screening of fungi with herbicidal potential and evaluation of herbicidal activity against Vernonia species

Abstract

In irrigated agriculture, weed control through chemical herbicides, creates various environmental and health hazards which lead to the search for an alternate method of weed management, which is an eco-friendly and effective means. Biological control of weeds using microorganism is now extensively studied to control various economic important weeds. In the present study, herbicidal activity of crude metabolites extracted from the fungal strains isolated from the soil was evaluated against Vernonia species. A total of 125 fungal soil isolates belonging to four fungal species such as Alternaria alternata, Paecilomyces farinosus, Penicillium expansum, and Fusarium oxysporum were isolated. The respective fungal isolates were cultivated in modified Fries media under standard condition. The mycelia and the filtrate were extracted with ethyl acetate and the concentrated extract was evaluated for the herbicidal activity adopting leaf necrosis assay. Among the different isolates, extract prepared from A. alternata and P. farinosus showed maximum herbicidal activity. The present study would suggest the possible use of the fungal extract as a bio-herbicidal agent after the effective formulation and mass production through standard conditions.

Keywords: Herbicidal activity, fungi, extracts, Vernonia species, formulation

African Journal of Biotechnology, Vol 13(52) 4653-4656