Effect of temperature on phenotype characterization of Ralstonia solanacearum from tobacco

• Published in: Canadian journal of plant pathology Vol. 42; no. 2; pp. 164 - 181
• Main Authors: Wang, Han-Cheng, Guo, Hua, Cai, Lin, Cai, Liu-Ti, Guo, Yu-Shuang, Ding, Wei
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 02.04.2020; Taylor & Francis Ltd
• Subjects: Amino acids; Bacteria; Carbohydrates; Carbon; Carbon sources; flétrissure bactérienne du tabac; L-Proline; metabolic phenotype; Metabolism; Nitrogen sources; Organic acids; Pathogens; phenomics; Phenotypes; phénomique; phénotype métabolique; Proline; Ralstonia solanacearum; Substrates; Temperature; Temperature effects; température; Tobacco; tobacco bacterial wilt; Wilt
• ISSN: 0706-0661; 1715-2992
• DOI: 10.1080/07060661.2019.1654547

The incidence of tobacco bacterial wilt, caused by Ralstonia solanacearum, is significantly affected by temperature. However, the effect of temperature on the metabolism of carbon and amino acid substrates used in phenotypic characterization of R. solanacearum is still unknown. In order to evaluate the effect of temperature on metabolic phenotypes, the phenotypes of the pathogen were characterized and compared with a BIOLOG Phenotype MicroArray (PM) at 20, 24, 30 and 35°C. The results showed that phenotypes of R. solanacearum at all four temperatures were mostly similar. However, a few differences were observed, such as in the ability to metabolize L-proline. The bacterium was able to metabolize more than 30% of the tested carbon sources and 83% of amino acid nitrogen substrates. For carbon sources, the most informative utilization patterns were organic acids and carbohydrates; for nitrogen sources, the most informative were amino acids. The bacterium showed much higher metabolic ability at 35°C than at 20, 24 and 30°C, and was more adaptable to osmolytes and pH environments at 30 and 35°C than at 20 and 24°C. It presented no deaminase activity, had high decarboxylase activity at 35°C and low decarboxylase activity at 20 and 24°C. When the phenotypic data were subjected to comparative phenomic analyses, temperature did have a significant effect on the characterization of the pathogen. The results provide clues to possible new methods to manage tobacco bacterial wilt.