Fig. 1

SIGS strategy to protect crops from the invasion of fungal pathogens F. oxysporum. Sprayed exogenous dsRNAs/sRNA can be taken directly into Fusarium cells on the plant vascular system or by first passing through the cells of the plant. In this case, the dsRNAs/sRNA are translocated through vascular system before delivery to the fungal hyphae or conidia. Alternatively, the exogenous processed and/or unprocessed dsRNA, as well as sRNA, are taken into the fungal cell either by haustorial feeding, endocytosis, or vesicle trafficking (the certain entry mechanism of dsRNA/sRNA into the fungal cell still to be determined). In Fusarium cell, the fungal RNAi machinery is guided by siRNAs derived from the exogenous dsRNA to mediate particular target gene silencing, finally leading to impair the pathogenicity of Fusarium pathogens. dsRNAs are processed by DCL family to produce siRNAs and subsequently loaded into the AGO complexes to induce targeted gene silencing (Hannon 2002; Baulcombe 2004; Koch et al. 2016; Ouyang et al. 2023). DCL, Dicer-like protein; AGO, Argonaute protein; Con, conidia; Grey dots, dsRNAs/sRNA. Red arrows, the moving direction of pathogens. Blue arrows, the moving direction of dsRNAs/sRNA