Antagonistic action of <i>Streptomyces pratensis</i>   <scp>S10</scp> on <scp> <i>Fusarium graminearum</i> </scp> and its complete genome sequence

Abstract

Wheat scab, mainly caused by Fusarium graminearum, can decrease wheat yield and grain quality. Chemical pesticides are currently the main control method but have an inevitable negative consequence on the environment and in food safety. This research studies a promising substitute, Streptomyces pratensis S10, which was isolated from tomato leaf mould and shows a significant inhibition effect on F. graminearum based on antagonism assays. The biocontrol mechanism is studied by enhanced green fluorescent protein labelling, quantitative real-time PCR, the Doskochilova 8 solvents system test and complete genome sequencing. Strain S10 can colonize in the wheat root, control wheat scab and decrease deoxynivalenol (DON) content. The control effects in vitro, planta and the plot experiments were 92.86%, 68.67% and 40.87% to 86.62%, respectively. S10 decreased DON content by inhibiting the mycelium growth and DON synthesis gene expression. The active substances of the S10 secondary metabolites had a high-temperature resistance and 29 putative biosynthetic gene clusters in its genome. The S10 control mechanism is multivariate, which shows potential in controlling wheat scab.