Figure 1.

The interaction between EPF and insects during the early infection stage. (A) A schematic diagram of fungal adhesion, pre-penetration, and the cuticular defense. The surface of EPF conidia is equipped with hydrophobins and other components facilitating adhesion. The appressorium initiates growth. Antifungal compounds present in the insect cuticle, glandular secretion, and ectomicrobiomes act to inhibit EPF conidial growth. (B) Strategies employed by insects to prevent and counteract EPF infection prior to establishment. EPF can attract insects through VOCs, such as acetic acid, 1-octen-3-ol and Chokol K, but insects can detect VOCs from EPF and avoid infection. EPF can also generate toxins to deter other organisms from consuming the infected insect cadavers in the last stage of infection. Social insects exhibit collective behaviors, like grooming and self-removal as a means to circumvent EPF infection.