Dictyophora indusiata and Bacillus aryabhattai improve sugarcane yield by endogenously associating with the root and regulating flavonoid metabolism

A mycorrhizae is a symbiotic relationship between a microorganism and a plant. This association improves plant growth and drought tolerance therefore used in crop growing. The present study discovered a novel phenomenon similar to ectomycorrhizae of root in a sugarcane and bamboo fungus (Dictyophora indusiata) intercropping system. Therefore, we investigated the mechanisms underlying the formation of this mycorrhizal-like association and its impact on sugarcane yield and metabolism by metabarcoding and metabolome analysis. Initial analysis revealed that intercropping with bamboo fungus increased sugarcane yield by enhancing the number of viable tillers compared with bagasse and no input control. Metabarcoding based on second-generation and third-generation sequencing indicated that Bacillus aryabhattai dominates the endophytic microbial composition in the sugarcane root system during D. indusiata symbiosis with roots cultivation. The coexistence of D. indusiata and B. aryabhattai as endophytes induced plant growth-promoting metabolites in the sugarcane root system, such as lysoPC 18:1 and dihydrobenzofuran, probably contributing to increased sugarcane yield. Furthermore, the association also enhanced the metabolism of compounds, such as naringenin-7-O-glucoside (Prunin), naringenin-7-O-neohesperidoside (Naringin)*, hesperetin-7-O-neohesperidoside (Neohesperidin), epicatechin, and aromadendrin (Dihydrokaempferol), involved in flavonoid metabolism during the formation of mycorrhizal-like structures in the sugarcane root system. These observations suggest that the mycorrhizal structure promotes sugarcane growth by activating flavonoid metabolism. This study reports an interesting phenomenon where D. indusiata, coordinate with the specific bacteria invade, forms a symbiotic relationship with sugarcane root, like an ectomycorrhizae. The study also provides new insights into using D. indusiata as a soil inoculant for promoting sugarcane growth and proposes a new approach for improve sugarcane cultivation study.