<i>In vitro</i> and <i>in vivo</i> inhibitory effects and transcriptional reactions of graphene oxide on <i>Verticillium dahliae</i>

The properties of graphene oxide (GO) against viruses and bacteria have received widespread attention, yet research into its antifungal capabilities remains comparatively scarce. Assessing the inhibitory effect of GO on plant pathogenic fungi is crucial for its application in preventing and managing fungal diseases. <i>Verticillium dahliae</i> represents a quintessential soil-borne fungal pathogen that infiltrates through plant roots and resides within the vascular tissues, leading to devastating wilt diseases. This research endeavored to explore the antimicrobial effect of GO on <i>V. dahliae</i> and to elucidate its underlying molecular mechanisms. Our findings revealed that GO exerted a significant inhibitory impact on mycelial growth and spore germination of <i>V. dahliae</i>. In addition, GO can significantly reduce the infection of <i>V. dahliae</i> on cotton. Biochemical analyses indicated that the DNA, RNA, malondialdehyde (MDA), and protein content within <i>V. dahliae</i> cells were markedly elevated post-GO treatment, underscoring the compromised cell membrane integrity. Transcriptome analysis revealed 1,149 differentially expressed genes (DEGs) during hyphal elongation and 1,078 DEGs in the process of spore germination. The downregulated genes predominantly encoded proteins involved in membrane integrity, such as intrinsic and integral membrane components, as well as proteins with oxidoreductase and transporter activities. Collectively, our data suggest that GO impedes mycelia growth and spore germination of <i>V. dahliae</i> by disrupting cell membrane integrity. This study offers novel perspectives for the development of antifungal agents and more precise clues to discover the mechanism by which GO suppresses the proliferation of <i>V. dahliae</i>.IMPORTANCEGO could suppress the proliferation of the mycelia and the initiation of spore germination of <i>V. dahliae</i>. In addition, the utilization of GO could mitigate the manifestations of cotton wilt resulting from the infection by <i>V. dahliae</i>. This study offers novel perspectives for the development of antifungal agents and more precise clues to discover the mechanism by which GO inhibits the growth of <i>V. dahliae</i>.