Aviglycine and propargylglycine inhibit conidial germination and mycelial growth of Fusarium oxysporum f. sp luffae

Abstract

Two inhibitors, aviglycine and propargylglycine, were tested for their ability to suppress methionine synthesis thus inhibit conidial germination and mycelial growth of Czapek-Dox liquid medium grown Fusarium oxysporum f. sp. luffae. Aviglycine inhibited conidial germination in the range of 0.3-7.6 muM. The linear inhibition range for mycelial growth was about 7.6-762.9 muM. Although aviglycine did not completely inhibit both conidial germination and mycelial growth, it showed significant inhibitory effect at 1.5 muM. The inhibition range for propargylglycine against conidial germination and mycelial growth were from 0.08 to 8841 muM and from 0.8 to 884.1 muM, respectively. Propargylglycine inhibited conidial germination and mycelial growth at a concentration of 8841 muM. The EC50 values of aviglycine were 1 muM for conidial growth and 122 muM for mycelial growth, and the EC50 values of propargylglycine were 47.7 muM for conidial growth and 55.6 muM for mycelial growth. Supplement of methionine released inhibition of aviglycine or propargylglycine to conidial germination. In addition, a mixture of aviglycine (1.5 muM) and propargylglycine (8841 muM) showed additive inhibitive effect than applied alone on 10 isolates. From these results, both aviglycine and propargylglycine exhibited inhibitory activity, and suggest that they can provide potential tools to design novel fungicide against fungal pathogens.