Pathogen-Induced Accumulation of an Ellagitannin Elicits Plant Defense Response

MAMANI, ALICIA; FILIPPONE, M.P.; GRELLET BOURNONVILLE, CF; WELIN, B.; CASTAGNARO AP.; DIAZ RICCI, JC

MOLECULAR PLANT-MICROBE INTERACTIONS

AMER PHYTOPATHOLOGICAL SOC

Año: 2012 p. 1 - 10

0894-0282

In an incompatible interaction between Colletotrichum fragariaeand strawberry plants, the accumulation of phenoliccompounds in plant leaves was observed. A particularlyabundant penta-esterified ellagitannin that accumulated inresponse to pathogen attack was identified as 1-0-galloyl2,3;4,6-bis-hexahydroxydiphenoyl-β-D-glucopyranose(HeT)by mass spectroscopy and nuclear magnetic resonance. Foliarapplication of purified HeT prior to inoculation with avirulent pathogen was shown to increase resistance towardC. acutatum in strawberry plants and to Xanthomonas citrisubsp. citri in lemon plants. The induced resistance instrawberry was associated with a rapid oxidative burst,callose deposition, a transient increase of salicylic acid inphloem, and induction of gene expression responsive tosalicylic acid. Results obtained suggested that HeT couldbe a common plant defense response molecule capable ofinducing pathogen resistance in different plant species.