Metabolomics of Disease Resistance in Crops

Abstract

Plants are continuously exposed to the attack of invasive microorganisms, such as fungi

or bacteria, and also viruses. To fight these attackers, plants develop different metabolic

and genetic responses whose final outcome is the production of toxic compounds that

kill the pathogen or deter its growth or semiotic molecules that alert other individuals of

the same plant species. These molecules are derived from the secondary metabolism and

their production is induced upon detection of a pathogen-associated molecular pattern

(PAMP). These PAMPs are different molecules that are perceived by the host cell

triggering defense responses. PAMP-elicited compounds are highly diverse and specific

of every plant species and can be divided into preformed metabolites or phytoanticipins

that are converted into toxic molecules upon pathogen perception, and toxic metabolites

or phytoalexins that are produced only upon pathogen attack. Moreover, plant volatile

emissions are also modified in response to pathogen attack to alert neighboring

individuals or to make plants less attractive to pathogen vector arthropods. Plant

metabolite profiling techniques have allowed the identification of novel antimicrobial

molecules that are induced upon elicitation. However, more studies are required to

assess the specific function of metabolites or metabolite blends on plant-microbe

interactions.