Effect of exogenously added ferulic acid on in vitroFusarium oxysporum f. sp. niveum

Allelochemicals from root exudates or decaying residues of watermelon plant may be related to watermelon fusarium wilt. The aim of this work was to study the effect of an artificially applied allelochemical, ferulic acid, on in vitroFusarium oxysporum f. sp. niveum (FON), a causal pathogen of plant wilting in the laboratory setting.The results showed that ferulic acid inhibited growth at high concentrations. The biomass was reduced by 71.6% and the conidial germinate rate was decreased by 100%, while mycotoxin production by FON was increased by 227.7% at the highest concentration (1600 mg L−1). Activities of hydrolytic enzymes related to pathogenicity were also affected.It is concluded that ferulic acid at commonly found concentrations inside plants suppressed the growth of pathogen F. oxysporum f. sp. niveum.