A semi-hydroponic cultivation system designed for collecting root exudates from maize in symbiosis with arbuscular mycorrhiza fungi

Abstract The collection of root exudates, particularly those from plants symbiotically associated with arbuscular mycorrhizal fungi (AMF), were notably challenging. A semi-hydroponic cultivation system (SHCS) was designed to collect rhizosphere exudates from maize in symbiosis with AMF. This system utilizes perlite as a solid support to simulate soil barriers, combined with drip irrigation to facilitate symbiosis and the collection of maize root exudates. SHCS consists of a culture bottle, a solution bottle providing nutrients, a peristaltic pump for powering the system, silicone tubes connecting all components, a flat-jaw pinchcock for operation, and a device shelf for placing all items. Then it was used to collect root exudates from maize-wild type B73 and AMF-inoculated B73, followed by metabolomics analysis using LC-MS/MS. Through comparative analysis, we identified significant differences in metabolite levels between B73 and RiB73. Briefly, a total of 54 metabolites exhibited AMF-related characteristics, and these metabolites were enriched in 15 metabolic pathways. Key metabolites include lumichrome, riboflavin, indolelactic acid, abscisic acid, gibberellin a116, and l-histidinol phosphate. Among them, l-histidinol phosphate significantly decreased after AMF inoculation, while the other metabolites showed a notable increase in content.