LAUSR

Modern strawberry production is often threatened by microbe pathogens. Anthracnose is among the most prominent fungal disease caused mainly by Colletotrichum gloeosporioides and leads to large-scale losses both in quality and yield. Little is known regarding the mechanisms underlying the genetics in the strawberry-C. gloeosporioides interaction. In the current research, a wild accession 'Fragaria nilgerrensis' is used as a resistant model to study the roles of terpenoid and terpene genes in leaf response to C. gloeosporioides. We found that several terpenoids and terpene genes were up-regulated at early time points after challenged with C. gloeosporioides. Among the metabolites detected, sesquiterpenes were the most significantly accumulated compounds, increasing up to ~12-fold at 18 h post infection (hpi), followed by monoterpenes which showed a slight increase upon infection. Consistently, the time-resolved transcriptome data revealed that genes pertaining to terpenoid metabolism were rapidly up-regulated and co-expressed with signaling pathway genes relevant to defense response. Notably, quantitative real-time PCR confirmed that the expression of five terpene synthase genes (TPS) were greatly enhanced, by a factor of one to three orders of magnitude at 3-6 hpi. Our results reveal a possible link between rapidly induced terpenoid metabolism and the autoimmunity underlying anthracnose resistance in a wild strawberry species.