# The FORGENIUS Genomic Resources: New Genotyping Tools and Genomic Data for 23 Forest Tree Species and Their Genetic Conservation Units

## TL;DR

The FORGENIUS project developed new genomic tools to study genetic diversity in 23 forest tree species, supporting conservation efforts in European forests.

## Contribution

The paper introduces standardized SPET-based genotyping tools for diverse forest tree species, enabling large-scale genetic monitoring.

## Key findings

- SPET panels captured ~10,000 loci per species, identifying over 1.8 million SNPs across 7220 trees.
- SPET panels showed high efficiency and cross-species transferability in genera like Quercus and Abies.
- The tools enable standardized genetic assessments and support conservation strategies for forest Genetic Conservation Units.

## Abstract

Genetic diversity is a critical but often overlooked component of biological diversity. The European H2020 FORGENIUS project is aimed at increasing the quality and quantity of genetic data to start monitoring the European network of forest Genetic Conservation Units (GCUs). A first step in this direction was developing standardised genomic resources for 23 forest tree species, spanning from rare and scattered (e.g., Abies nebrodensis and Torminalis glaberrima) to widespread and stand‐forming, economically relevant ones (e.g.,
Fagus sylvatica
,
Picea abies
and
Pinus sylvestris
). Here, we describe the development and application of targeted genotyping tools, primarily based on Single Primer Enrichment Technology (SPET), along with existing SNP arrays for the selected species. The SPET panels developed in FORGENIUS were designed to capture ⁓10,000 loci per species, balancing species‐specific and randomly distributed regions to ensure broad genome coverage and minimise ascertainment bias. Across 7220 genotyped trees, we identified over 1.8 million single nucleotide polymorphisms (SNPs) covering approximately 50 Mb of DNA sequence. SPET panels demonstrated high genotyping efficiency and cross‐species transferability, especially within genera such as Quercus and Abies. They represent a cost‐effective, flexible, and scalable solution for population‐level genetic assessments across diverse taxa, enabling standardised, genome‐wide characterisation of the GCU network. These resources not only promote the establishment of genetic monitoring, support genetically informed conservation strategies and improve our understanding of adaptive responses in European forests, but also enhance species delimitation and hybrid detection, and enable the characterisation of phylogenetically related but previously underexplored species.