Symbiotic performance and induction of systemic resistance against Cercospora sojina in soybean plants co-inoculated wit
- PDF / 713,056 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 23 Downloads / 212 Views
ORIGINAL PAPER
Symbiotic performance and induction of systemic resistance against Cercospora sojina in soybean plants co‑inoculated with Bacillus sp. CHEP5 and Bradyrhizobium japonicum E109 María Laura Tonelli1 · C. Magallanes‑Noguera1 · A. Fabra1
Received: 30 November 2016 / Revised: 9 June 2017 / Accepted: 14 June 2017 © Springer-Verlag GmbH Germany 2017
Abstract Soybean is an economically very important crop throughout the word and particularly in Argentina. Soybean yield may be affected by many factors such as the lack of some essential nutrients or pathogens attack. In this work we demonstrated that the co-inoculation of the native biocontrol bacterium Bacillus sp. CHEP5 which induces resistance against Cercospora sojina in soybean and the nitrogen fixing strain Bradyrhizobium japonicum E109, was more effective in reducing frog leaf spot severity than the inoculation of the biocontrol agent alone. Probably, this is related with the increase in the ability to form biofilm when both bacteria are growing together. Furthermore, Bacillus sp. CHEP5 inoculation did not affect Bradyrhizobium japonicum E109 symbiotic behavior and flavonoids composition of root exudates in pathogen challenged plants. These results suggest that co-inoculation of plants with rhizobia and biocontrol agents could be a strategy to improve soybean production in a sustainable system. Keywords Soybean · Bacillus sp. · Cercospora sojina · Induced systemic resistance · Bradyrhizobium japonicum E109 · Nodulation
Communicated by Jorge Membrillo-Hernández. * María Laura Tonelli [email protected] 1
Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico‑Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal 3, 5800 Río Cuarto, Córdoba, Argentina
Introduction The rhizosphere is inhabited by a great amount of beneficial and pathogenic microorganisms. Some of them establish a close interaction with plants, colonizing their roots or aerial tissues and triggering a specific response. Hence, plants have developed an efficient recognition machinery to discriminate and perform an accurate and fast response towards their presence or contact. The recognition between plants and microorganisms is mediated by a molecular dialog that finally induces plant defense responses or stimulates the establishment of mutualistic relationships (Yamazaki and Hayashi 2015). PGPB (plant-growth-promoting bacteria) stimulate plant growth by direct or indirect mechanisms. The main mechanisms for plant growth promotion include suppression of disease (biocontrol), enhancement of nutrient availability (biofertilization), and production of plant hormones (phytostimulation) (Bhattacharyya and Jha 2012). Among PGPB, microorganisms called rhizobia induce nodule formation on root of legumes where bacteria provide fixed nitrogen for the host (Podile and Kishore 2006; Lugtenberg and Kamilova 2009; Fabra et al. 2010). Other PGPB are able to induce systemic resistance (ISR) in their host, triggering plant defense state only upon pathogen a
Data Loading...
