Interactions between rootstock and scion during grafting and their molecular regulation mechanism

• Rootstock affected gene expressions in the scion. • mRNAs in rootstock and scion played an important role in information transfer. • The miRNAs involved in the regulation of grafting were briefly described. • DNA methylation in grafting. Grafting is an important method to improve plant yield and quality. The rootstock is vital to the scion in terms of growth and development, flowering and fruit set, and improved stress resistance. In the course of grafting, the rootstock and scion interactions and their molecular regulation mechanisms are extremely complex. This paper mainly discussed the following 7 changes happened to the plant during grafting: morphological characteristics of rootstock and scion healing, compound exchange between rootstock and scion interactions, phytohormone regulatory effects, gene expression, long-distance transport of mRNAs, mediating effects of sRNAs, and DNA methylation. It was aimed to provide a reference basis for efficient use of grafting technology to improve crop yield and quality, and to shorten crop breeding cycles.