Hairy Root Composite Plant Systems in Root-Microbe Interaction Research

Abstract

Plant-associated microbes are key determinants of plant health and productivity. Research on model plant species has helped discover fundamental plant mechanisms that determine the outcomes of these microbial interactions. However, the species-specific nature of several key plant-microbe interactions necessitates research in non-model plant species. A major bottleneck for research on non-model species is the lack of efficient transformation methods. Agrobacterium rhizogenes-mediated hairy root composite plant system is a transformative tool that has enabled a multitude of transgenic approaches to be efficiently used in non-model species. This chapter provides a snapshot of research using key examples to highlight how the tool had helped advance the frontier of root-microbe interaction research focusing on arbuscular mycorrhizal symbiosis, nodulation, pathogen responses, and microbiome research. Limitations of and recent developments in hairy root composite plant systems are also discussed.