Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: Chemical Biology of Insect and Plant Signaling Systems

Location: Chemistry Research Unit

Title: Biosynthesis, regulation and roles of monocot terpenoid phytoalexins

Authors
item Schmelz, Eric
item Huffaker, Alisa
item SIMS, JAMES
item CHRISTENSEN, SHAWN
item Lu, Xuan -
item Okada, Kazunori -
item Peters, Reuben -

Submitted to: Plant Journal
Publication Type: Review Article
Publication Acceptance Date: January 17, 2014
Publication Date: N/A

Technical Abstract: A long standing goal in plant defense research is to optimize the protective function of biochemicals that impede pathogen and pest attack. Nearly 40 years ago pathogen-inducible non-volatile diterpenoids were described in rice and demonstrated to function as potent antimicrobial phytoalexins. Using rice and maize as examples, we discuss recent advances in the identification, biosynthesis, elicitation, signaling and function of inducible terpenoid phytoalexins. The rate of monocot terpenoid phytoalexin discovery in additional species is likely to increase through recent advances in sequencing and annotation that are uncovering cereal genes displaying inducible transcript accumulation for previously uncharacterized terpene synthases. Genetic evidence suggests that terpenoid phytoalexins may occur widely in key cereal crops and should aid in discoveries outside of the Poaceae. Biochemical discoveries are actively pairing terpenoid phytoalexin precursors and endproducts with cognate biosynthetic pathway genes. In addition to classical antimicrobial functions, examples of root exudate-mediated allelopathy and insect-elicitation coupled with antifeedant activity encourage a consideration of additional ecological roles for phytoalexins that blur traditionally discrete classifications. Critical examination of these biological roles is aided by the establishment of rice and maize mutant collections and genetic transformation. Collectively these approaches enable the additional examination of terpenoid phytoalexin precursors and endproducts as potential signals mediating further plant physiological processes.

Last Modified: 9/10/2014
Footer Content Back to Top of Page