Datensatz

Zusammenfassung

Insect herbivory can seriously hinder plant
performance and reduce crop yield. Thrips are minute
cell-content-feeding insects that are important vectors of
viral plant pathogens, and are serious crop pests. We
investigated the role of a sweet pepper (Capsicum annuum)
lipoxygenase gene, CaLOX2, in the defense of pepper plants
against Western flower thrips (Frankliniella occidentalis).
This was done through a combination of in-silico, transcriptional,
behavioral and chemical analyses.Our data showthat
CaLOX2 is involved in jasmonic acid (JA) biosynthesis and
mediates plant resistance. Expression of the JA-related
marker genes, CaLOX2 and CaPIN II, was induced by thrips
feeding. Silencing of CaLOX2 in pepper plants through virusinduced
gene silencing (VIGS) resulted in low levels of
CaLOX2 transcripts, as well as significant reduction in the
accumulation of JA, and its derivatives, upon thrips feeding
compared to control plants. CaLOX2-silenced pepper plants
exhibited enhanced susceptibility to thrips. This indicates
that CaLOX2 mediates JA-dependent signaling, resulting in
defense against thrips. Furthermore, exogenous application
of JA to pepper plants increased plant resistance to thrips,
constrained thrips population development and made
plants less attractive to thrips. Thus, a multidisciplinary
approach shows that an intact lipoxygenase pathway mediates various components of sweet pepper defense against F. occidentalis.