Research Technician University of Georgia Athens, Georgia
Body of Abstract: De novo root regeneration (DNRR) is a type of wound-induced tissue regeneration solely relying on endogenous hormones. While wounding initiates DNRR, it also induces immunity responses which inhibit DNRR. Plants can recognize molecules derived from microbial pathogens and activate immunity. However, previous studies of DNRR were performed in aseptic conditions, so it is unclear how microbes induce or inhibit DNRR. We developed a method which can support DNRR in the environment with microbes. Using this method, we found that pathogenic bacteria and its disarmed mutant inhibited DNRR, while E. coli didn’t affect DNRR. Receptor complex recognizing pathogen-associated molecular pattern (PAMP) is required for flagellin 22 (flg22) peptide mediated inhibition of DNRR, while the inhibition may bypass the requirement of salicylic acid (SA) signaling pathway. Soil microbes could also inhibit DNRR when PTI and SA pathway were compromised. Auxin transportation and cell fate transition were inhibited in both flg22 and soil microbes treated explants. In summary, pattern-triggered immunity (PTI) can inhibit DNRR while other signaling pathways may also inhibit DNRR with the presence of some microbe strains. Our study provided a way to dissect the impact of microbes on regeneration.