Perspectives on the metabolism of strigolactone rhizospheric signals

• DOI: 10.3389/fpls.2022.1062107
• Publication Date: 2022-11-24T08:04:41Z
• Authors: Jian You Wang; Justine Braguy; Guan-Ting Erica Chen; Muhammad Jamil; Aparna Balakrishna; Lamis Berqdar; Salim Al-Babili
• Keywords: 0301 basic medicine; 2. Zero hunger; 0303 health sciences; 03 medical and health sciences; striga; Plant culture; root exudate; strigolactones; rice (Oryza sativa); Plant Science; LC-MS/MS; rhizosphere; SB1-1110

Strigolactones (SLs) are a plant hormone regulating different processes in plant development and adjusting plant’s architecture to nutrition availability. Moreover, SLs are released by plants to communicate with beneficial fungi in the rhizosphere where they are, however, abused as chemical cues inducing seed germination of root parasitic weeds, e.g. Striga spp., and guiding them towards host plants in their vicinity. Based on their structure, SLs are divided into canonical and non-canonical SLs. In this perspective, we describe the metabolism of root-released SLs and SL pattern in rice max1-900 mutants, which are affected in the biosynthesis of canonical SLs, and show the accumulation of two putative non-canonical SLs, CL+30 and CL+14. Using max1-900 and SL-deficient d17 rice mutants, we further investigated the metabolism of non-canonical SLs and their possible biological roles. Our results show that the presence and further metabolism of canonical and non-canonical SLs are particularly important for their role in rhizospheric interactions, such as that with root parasitic plants. Hence, we proposed that the root-released SLs are mainly responsible for rhizospheric communications and have low impact on plant architecture, which makes targeted manipulation of root-released SLs an option for rhizospheric engineering.