Aspergilli Screened For Antagonistic Effects On Fungal Plant Pathogens And For Endoglucanase And Xylanase Activities

Abstract

Twenty-six selected Aspergilli isolates were quantitatively pre-screened for endoglucanase and xylanase activities and for antagonistic effect on growth of plant pathogens using a dual plug inoculation method on agar plates. The Aspergilli were identified based on β-tubulin and calmodulin gene sequencing data using GenBank-based BLASTn analysis (NCBI). Antagonistic activity of the Aspergilli against fungal plant pathogens (i.e., Curvularia eragrostidis, Colletotrichum gloeosporioides, Neopestalotiopsis clavispora, Fusarium incanatum and Sclerotium rolfsii) was measured in vitro after seven days of incubation at room temperature. The highest antagonistic Aspergilli against Curvularia eragrostidis, Colletotrichum gloeosporioides, Neopestalotiopsis clavispora, Fusarium incanatum and Sclerotium rolfsii were identified as Aspergillus carbonarius WP 2, A. parasiticus JNF 222, A. carbonarius WP 2, A. carbonarius TBRC 402 and A. giganteus TBRC 400, respectively. The highest enzymatic index (EI) of endoglucanase and xylanase activity found in Aspergillus puniceus TBRC 2711 and A. candidus TBRC 2770 were 2.92 and 2.88, respectively. In this study, the preliminary screening reveals the potential of Aspergilli isolates as sources of endoglucanase and xylanase activity and as effective biocontrol agents against plant pathogenic fungi.