INVESTIGADORES
GARRIZ Andres
congresos y reuniones científicas
Título:
The PGPR Burkholderia sp. (AU4I) protects Arabidopsis thaliana against fungal pathogens through direct inhibition and modulation of defense and plant cell wall metabolism
Autor/es:
COLAVOLPE BELEN; ANDRÉS GÁRRIZ; VILLARREAL NATALIA; FR ROSSI; FM ROMERO; OA RUIZ; SAINI ADESH; MARINA M
Lugar:
Barcelona
Reunión:
Congreso; XXII Congreso de la Sociedad Española de Fisiología Vegetal; 2017
Resumen:
Burkholderia sp. (AU4i), a strain which can acts as PGPR (Plant Growth-Promoting Rhizobacteria) inplants, was previously isolated from pea. We demonstrated that AU4i is able to grow endophytically onArabidopsis plants and promote Arabidopsis growth increasing the number of lateral roots as well as rootand shoot dry weight. To evaluate the potential of AU4i as a biocontrol agent, leaves inoculated with AU4iwere challenged with the necrotrophic pathogens Botrytis cinerea and Sclerotinia sclerotiorum. Thenecrotic lesion areas provoked by both pathogens were reduced in leaves previously inoculated by AU4i.Additionally, AU4i was capable to inhibit the in vitro growth of B. cinerea, but not of S. sclerotiorum. Inother hand, AU4i was able to induce the expression of the jasmonate responsive marker gene PDF1.2, butnot the expression of salicylic acid marker gene (PR-1). The protective effect of AU4i against fungalpathogens was evaluated in Arabidopsis defense signaling pathways mutant plants, coi1 (defective injasmonate perception) and sid2-2 (defective in salicylic acid synthesis). Similar protective effect wasobserved in both lines in comparison to Col-0 plants, suggesting the independence of the AU4i protectiveeffect and plant signaling pathways. As well, the effect of AU4i inoculation on plant cell wall metabolismduring that endophytic interaction was evaluated. As a result it was revealed that AU4i modulates host cellwall metabolism, through the down-regulation of genes involved in hemicellulose and pectins lateral chainsdegradation (AtExp8 and AtAra1, respectively) and the up-regulation of AtPME3, a gene encoding aputative pectin methylesterase involved in pectin main chain esterification. Taken together, our resultssuggest that Burkholderia sp. AU4i might be a good candidate as a biocontrol agent