Unveiling the Mechanisms for the Plant Volatile Organic Compound Linalool To Control Gray Mold on Strawberry Fruits

Fungal infections significantly alter
the emissions of volatile organic compounds (VOCs) by plants, but
the mechanisms for VOCs affecting fungal infections of plants remain
largely unknown. Here, we found that infection by Botrytis
cinerea upregulated linalool production by strawberries
and fumigation with linalool was able to inhibit the infection of
fruits by the fungus. Linalool treatment downregulated the expression
of rate-limiting enzymes in the ergosterol biosynthesis pathway, and
this reduced the ergosterol content in the fungi cell membrane and
impaired membrane integrity. Linalool treatment also caused damage
to mitochondrial membranes by collapsing mitochondrial membrane potential
and also downregulated genes involved in adenosine triphosphate (ATP)
production, resulting in a significant decrease in the ATP content.
Linalool treatment increased the levels of reactive oxygen species
(ROS), in response to which the treated fungal cells produced more
of the ROS scavenger pyruvate. RNA-Seq and proteomic analysis data
showed that linalool treatment slowed the rates of transcription and
translation.