Molecular Aspects Of Grafting In Woody Plants

Grafting is an ancient technique especially used in horticulture and in orchards as a tool for plant propagation and improvement. Although grafting has brought incredible benefits to agriculture and is being used worldwide in the cultivation of almost every fruit tree, the mechanisms, and pathways driving the formation or the incompatibilities of graft unions are still largely unknown.Recently, the potential of grafting has resurfaced in the literature and molecular approaches are currently contributing to the understanding of graft union formation and the phenomenon of scion-rootstock graft incompatibility. This work focuses on the cellular and molecular mechanisms of graft formation in woody plants, highlighting the identified regulators of this process in molecular terms. We review how the healing of the union proceeds in incompatible grafts, the challenge of phenotyping graft incompatibility, and the detection methods developed for its prediction. In the pursuit of finding sustainable solutions for agriculture, while faced with the alarming predictions of climate changes, grafting is being revaluated as a new biotechnological tool. Therefore, some examples of howwe can broaden the scope of useful grafting applications, exploit biodiversity in a unique chimeric plant, and manipulate phenotypic traits by delivering proteins and RNAs across graft unions, are also discussed. Research in this field still has a long way to go before the exciting prospect of deliberately combining multiple plant traits becomes reality.