Morphological and Transcriptional Characteristics of the Symbiotic Interaction between and .

Ectomycorrhiza (ECM) function has been well studied; however, there is little detailed information regarding the establishment of ECM symbioses. We investigated the morphological and transcriptional changes that occur during the establishment of the - ECM. promoted the growth of via the release of volatile organic compounds and exudates during the pre-symbiotic stage. Exudate-induced effects showed host plant specificity. At seven days post-inoculation (dpi), the mycelium started to penetrate roots. At 28 dpi, the Hartig net and mantle formed. At the pre-symbiotic stage, most differentially expressed genes in roots were mapped to the biosynthesis of secondary metabolites, signal transduction, and carbohydrate metabolism. At the symbiotic stage, colonization induced the reprogramming of pathways involved in genetic information processing in , particularly at the Hartig net and mantle formation stage. Phenylpropanoid biosynthesis was present at all stages and was regulated via colonization. Enzyme inhibitor tests suggested that hydroxycinnamoyl-CoA shikimate/quinate transferase is involved in the development of the Hartig net. Our findings outline the mechanism involved in the - ECM. Further studies are needed to clarify the role of phenylpropanoid biosynthesis in ECM formation.