Contribution in an anthology

Appeared in: Belowground Defence Strategies in Plants

Editor list: Vos, CMF; Kazan, Kemal

Publication year: 2016

Pages: 329-339

ISBN: 978-3-319-42317-3

eISBN: 978-3-319-42319-7

DOI Link: https://doi.org/10.1007/978-3-319-42319-7_14

Title of series: Signaling and Communication in Plants

Abstract: 

The Alphaproteobacterium Rhizobium radiobacter F4 (RrF4) was originally detected as an endofungal bacterium associated with the endophytic basidiomycete Piriformospora indica that forms a beneficial symbiosis with a wide range of green plants. While attempts to cure P. indica from RrF4 repeatedly failed, the bacterium could be isolated and grown in pure culture. In contrast to some other endofungal bacteria, the genome size of RrF4 is not reduced. Instead, it shows a high degree of similarity to the plant pathogenic R. radiobacter (formerly: Agrobacterium tumefaciens) C58, except vibrant differences in both the tumor-inducing (pTi) and the accessor (pAt) plasmids, which can explain the loss of RrF4’s pathogenicity. Similar to its fungal host, RrF4 colonizes plant roots without host preference and forms aggregates of attached cells and dense biofilms at the root surface of maturation zones. RrF4-colonized plants show increased biomass and enhanced resistance against bacterial and fungal leaf pathogens. Resistance mediated by RrF4 is dependent on the plant’s jasmonate-based induced systemic resistance (ISR) pathway while the systemic acquired resistance (SAR) pathway is non-operative as shown by genetic analysis. Based on these findings we concluded that RrF4- and P. indica-induced pattern of defence gene expression are similar. However, in clear contrast to P. indica, but similar to plant growth promoting rhizobacteria (PGPR), RrF4 colonized not only the root outer cortex but spread beyond the endodermis into the stele. Based on our findings RrF4 is an efficient plant growth promoting bacterium.

Harvard Citation style: Alabid, I. and Kogel, K. (2016) Defence Reactions in Roots Elicited by Endofungal Bacteria of the Sebacinalean Symbiosis, in Vos, C. and Kazan, K. (eds.) Belowground Defence Strategies in Plants. Cham: Springer International Publishing, pp. 329-339. https://doi.org/10.1007/978-3-319-42319-7_14

APA Citation style: Alabid, I., & Kogel, K. (2016). Defence Reactions in Roots Elicited by Endofungal Bacteria of the Sebacinalean Symbiosis. In Vos, C., & Kazan, K. (Eds.), Belowground Defence Strategies in Plants (pp. 329-339). Springer International Publishing. https://doi.org/10.1007/978-3-319-42319-7_14