H2020 G2P-SOL Project: Linking genetic resources, genomes and phenotypes of solanaceous crops.

Inventory and conservation: A common descriptor system has been developed for all four crops. Existing passport and phenotypic data, including images, have been compiled for approximately 55,000 accessions across all four crops, as detailed in Table 1. All data have been uploaded to the G2P-SOL gateway (http://www.g2p-sol.eu/G2P-SOL-gateway.html) and are publicly accessible to all users since 1 January 2020. Description and evaluation: Low-density genotyping protocols, capable of scoring 2,000 to 5,000 genetic loci, have been optimized and used to genotype approximately 38,000 accessions and pre-breeding lines across all four crops, as detailed in Table 2. The data have been added to the G2P-SOL gateway.

The data for pepper are public; data for the other three crops will be made public after publication of the relevant articles. Five core collections (tomato, eggplant, pepper, South American and European potatoes), each composed of 300–400 individuals and representing the global or (in the case of potato) regional diversity of these crops, were constructed based on phenotypic parameters and low-density genotyping data and distributed to phenotyping partners. At least two field/cultivation trials were conducted for the five core collections. Phenotyping was performed using common protocols, and metabolic profiling was completed for tomato, eggplant, and pepper. Tests were also performed for selected biotic/abiotic stress resistance traits. The tomato and eggplant core collections were resequenced to a depth of 20x, while those for potato and pepper were subjected to high-density genotyping. In addition, 16 pepper genotypes, 47 eggplant wild accessions, 30 potato genotypes, and 42 tomato genotypes were resequenced to a depth of 20x–40x, for a total of over 5 terabases. Resequencing of the tomato and eggplant core collections generated, respectively, 30.1 million and 51.6 million single nucleotide polymorphisms (SNPs), of which, after filtering, 1.02 million and 1.32 million were used for genome-wide association mapping. The number of SNPs was much lower in pepper and potato, which underwent GBS (Table 3).

These SNPs were used along with dozens (potato) or hundreds (tomato, eggplant, pepper) of traits measured in core collections for genome-wide association studies, generating thousands of highly significant SNP/trait associations. Pre-breeding. More than 50 segregating populations of the four crops, derived from intra- or interspecific crosses, are being evaluated for a variety of new traits related to quality and disease resistance.

A number of known agronomic traits have been introgressed into new elite germplasm in a first pre-breeding wave, and several new traits have been validated for use in a second pre-breeding wave, as detailed below. The number of these traits is well above the 2-3 traits/crop initially planned. Aubergine: known 6; new 11; Pepper: known 6; new 7; Tomato: known 8; new 3; Potato: known 3; new 4 (Table 4). Dissemination, valorization and training The project results have been disseminated so far through 69 press releases, participation in 36 scientific conferences/workshops/events and 52 peer-reviewed and open access scientific articles. A list of all publications can be found on the G2P-SOL website ( http://www.g2p-sol.eu/Publications.html ). Two initial training courses on the use of genetic resources were organized in Hyderabad (India) and Lima (Peru), respectively, and two advanced training courses were held online in Wageningen (Netherlands). The project's final workshop (http://www.g2p-sol.eu/G2P%2DSOL%2DFinal%2DWorkshop.html) attracted over 1,000 participants from 61 countries (Figure 1). The project's Twitter account (@solgenetics) has over 300 followers.