In vitro antifungal activity of soil fungi crude extracts isolated from riparian forest against plant pathogenic fungi

Abstract

Fungal diseases affecting plants are one of the most destructive diseases and cause significant losses in many economic crops in Thailand and worldwide. The most common plant pathogenic fungi which cause severe diseases to economic crops in Thailand are Lasiodiplodia theobromae, Sclerotium rolfsii, Phytophthora palmivora, Colletotrichum capsici, Pyricularia grisea, Alternaria sp., Helminthosporium maydis, Rhizoctonia solani, Fusarium oxysporum and Colletotrichum gloeosporioides. Control of these pathogens is carries out through the use of synthetic fungicides which are harmful to environment. This study aims to at investigating the efficacy of the ethyl acetate crude extracts of the cultures Talaromyces flavus Bodhi003, NeosartoryafischeriBodhi004 and Eurotium sp. Bodhi005 isolated from riparian forest soils to inhibit the mycelial growth of ten plant pathogenic fungi in in vitro conditions at various concentrations. At the highest concentrations (10,000 ppm), all crude extracts exhibited a complete mycelial growth inhibition of some plant pathogenic fungi when compared with the water control. Interestingly, Eurotium sp. Bodhi005 crude extract was recorded as having excellent inhibitory activity against S. rolfsii at 1,000 ppm concentration. Results from this study demonstrate that ethyl acetate crude extracts from T. flavus Bodhi003,N. fischeriBodhi004, and Eurotium sp. Bodhi005 could be used to control the mycelial growth of plant pathogenic fungi and allow researcher to identify new potential sources for the development of alternative biofungicide to reduce plant pathogenic fungi. © 2016, Crop Protection Research Centre. All rights reserved.