Red seaweed-derived formulations enhance anti‑bacterial defenses in Arabidopsis thaliana and rice

Every year, huge losses in agriculturally important crops occur due to bacterial pathogen infestations. Due to their broad-spectrum anti-microbial activity, application of seaweed extracts (SWEs) demonstrate high potential as a viable environment-friendly crop loss prevention method. Two extracts from the red algae, Kappaphycus alvarezii, Tomatough® (LBD3) and AgFort® (LBD 12) were developed (by Sea6 Energy Pvt. Ltd, Bengaluru, India) based on differential bio-conversion of biomass. We demonstrate the efficacy of these products towards improving Pseudomonas syringae resistance in Arabidopsis thaliana, and Xanthomonas oryzae resistance in rice. Foliar application of these formulations, provide significant reduction in bacterial multiplication in planta due to augmented upregulation of defense-associated genes and increased accumulation of defensive hormone salicylic acid, jasmonic acid, and cytokinins. Our data shed more light on the molecular signalling mechanism underlying the resistance mediated by these formulations. These findings pave the way towards the development and testing of other algal-derived natural extracts as non-biodegradable alternatives to improve broad-spectrum plant defenses.

For full article: Roy et al., (2022) J. Appl. Phycol. https://doi.org/10.1007/s10811-021-02658-y