Volatile dimethyl disulfide affects root system architecture of Arabidopsis via modulation of canonical auxin signaling pathways

Microbial originated volatile organic compounds (VOCs) are reported to play significant roles in plant development and growth by interfering with the synthesis, metabolism, or signaling of phytohormones. Here, we demonstrated dimethyl disulfide (DMDS), a VOC previously known to be produced from rhizobacteria/fungi, modulated growth and root system architecture of Arabidopsis thaliana . Changes in root system architecture were correlated with auxin signalling intensities which were assessed by expression of auxin signaling reporter (i.e. DR5::GUS ) and early auxin responsive genes (e.g. SAUR - AC1, GH3.1, IAA14 ). Ultimately, Arabidopsis mutants aborted in auxin signalling (e.g. tir1 - 1, arf7 , arf7arf19 ) displayed insensitivity to DMDS in lateral root formation and suggested that DMDS can contribute to plant growth and development by modifying the root system architecture through canonical auxin signalling pathways in Arabidopsis .