MOHAN KUMAR RAMASAMY
Articles written in Journal of Biosciences
Volume 44 Issue 4 September 2019 Article ID 0098 Article
Pseudomonas putida is widely used as a biocontrol agent, however, mechanisms by which it initiates the plants’ defenseresponse remains obscure. To gain an insight into the molecular changes that occur in plants upon plant growth-promotingrhizobacteria colonization, root transcriptome analysis by using a microarray was performed in rice using P. putida RRF3 (arice rhizosphere isolate). Data analysis revealed a differential regulation of 61 transcripts (48 h post-treatment), of which,majority corresponded to defense response, cell wall modification and secondary metabolism. Seven genes encodingsalicylic acid (SA) responsive pathogenesis-related proteins were up-regulated significantly (fold change ranges from 1 to4), which suggests that RRF3 has a profound impact on a SA-mediated defense signaling mechanism in rice. Investigationsperformed at later stages of RRF3 colonization by real-time polymerase chain reaction and high-performance liquidchromatography (HPLC) analysis confirmed the above results, demonstrating RRF3 as a potent biocontrol agent. Further,the impact of RRF3 colonization on root exudation, in particular, exudation of SA was investigated by HPLC. However,analysis revealed RRF3 to have a negative impact on root exudation of SA. Overall, this study shows that P. putida RRF3immunizes the rice plants by re-organizing the root transcriptome to stimulate plant defense responses (‘priming’), andsimultaneously protects itself from the primed plants by altering the rhizosphere chemical constituents.
Volume 45, 2020
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode