Skip to main content
SLU publication database (SLUpub)

Research article1999Peer reviewed

The plant-growth-promoting rhizobacterium Paenibacillus polymyxa induces changes in Arabidopsis thaliana gene expression: A possible connection between biotic and abiotic stress responses

Timmusk, Salme; Wagner, Gerhart

Abstract

This paper addresses changes in plant gene expression induced by inoculation with plant-growth-promoting rhizobacteria (PGPR). A gnotobiotic system was established with Arabidopsis thaliana as model plant, and isolates of Paenibacillus polymyxa as PGPR. Subsequent challenge by either the pathogen Erwinia carotovora (biotic stress) or induction of drought (abiotic stress) indicated that inoculated plants were more resistant than control plants. With RNA differential display on par allel RNA preparations from P. polymyxa-treated or untreated plants, changes in gene expression were investigated. From a small number of candidate sequences obtained by this approach, one mRNA segment showed a strong inoculation-dependent increase in abundance. The corresponding gene was identified as ERD15, previously identified to be drought stress responsive. Quantification of mRNA levels of several stress-responsive genes indicated that P. polymyxa induced mild biotic stress. This suggests that genes and/or gene classes associated with plant defenses against abiotic and biotic stress may be co-regulated. Implications of the effects of PGPR on the induction of plant defense pathways are discussed.

Keywords

dehydration; RT-PCR

Published in

Molecular plant-microbe interactions
1999, Volume: 12, number: 11, pages: 951-959
Publisher: AMER PHYTOPATHOLOGICAL SOC