Session: Parallel session 8 - Plant and Food OMICS

Impact of Rhamnolipids (RL), natural defense elicitors, on Brassica napus shoots and roots using quantitative approaches

The rapeseed crop is susceptible to many pathogens such as parasitic plants or fungi attacking aerial or root parts. Conventional plant protection products, used intensively in agriculture, have a negative impact on the environment as well as on human health. There is therefore a growing demand for the development of more planet-friendly alternative protection methods such as biocontrol compounds. Natural rhamnolipids (RLs) can be used as elicitors of plant defense mechanisms.

These glycolipids, from bacteria secretome, are biodegradable, non-toxic and are known for their stimulating and protective effects, in particular on rapeseed against filamentous fungi. Characterizing the organ responsiveness to defense-stimulating compounds such as RLs is missing. This analysis is crucial in the frame of optimizing the effectiveness of RLs against various diseases. A Tandem Mass Tags (TMT) labeling of the proteins extracted from the shoots and roots of rapeseed has been performed and showed a differential pattern of protein abundance between them. Quantitative proteomic analysis highlighted the differential accumulation of parietal and cytoplasmic defense or stress proteins in response to RL treatments with a clear effect of the type of application. 

Additionally, the use of Multiple Reaction Monitoring (MRM) for studying phytohormones in rapeseed offers a highly sensitive and specific approach to understanding plant defense mechanisms. Phytohormones are crucial in regulating plant responses to pathogens, and their precise quantification is vital for developing effective biocontrol strategies. This method reveals how RL treatments influence phytohormone concentrations, offering insights into the hormonal pathways activated in response to pathogen attacks. Employing MRM helps researchers understand complex hormonal signaling networks in plant defense, leading to improved and environmentally friendly methods for protecting rapeseed crops from diseases.