Biotechnological Advances for Enhancing European Chestnut Resistance to Pests, Diseases, and Climate Change

Biotechnological tools have emerged as key alternatives for the protection, improvement, and sustainable use of forest species. This paper analyzes the main biotechnological strategies applied to the European chestnut, a species of significant ecological, economic, and cultural importance in many temperate regions. However, in recent decades, it has been seriously threatened by various factors, including devastating diseases such as chestnut blight and ink disease, as well as the impacts of climate change. First, classical and assisted breeding techniques are discussed, including controlled hybridization and the use of molecular markers to accelerate the selection of genotypes of interest. In the field of molecular biotechnology, studies related to the identification of key genes, the development of genetic markers (e.g., SSRs and SNPs), and the omics characterization of chestnut are reviewed. The use of micropropagation techniques for the clonal multiplication of elite individuals is also included. Furthermore, advances in genetic modifications are explored, highlighting the introduction of resistance genes through transgenic and cisgenic approaches, as well as emerging technologies such as CRISPR/Cas9. In the future, the integration of classical breeding with advanced genomics will enable the precise selection and accelerated development of European chestnut varieties, combining traditional trait improvement with genomic tools such as marker-assisted selection, genomic prediction, and gene editing to enhance disease resistance and climate resilience.