Genetic and adaptive diversity of wild tomato (Solanum spp.) in three basins of Lima: Identification of genetic resources for resilience to abiotic stress
TL;DR
Findings identify wild populations in Lima as critical reservoirs for reintroducing resilience into cultivated tomato in the face of climate change and its impact on food security.
Abstract
We characterised the biodiversity of wild tomato in the Lurín, Rímac and Chillón river basins, in the Lima valley, and analysed in silico five families of abiotic resistance genes. Sampling was carried out between 628 and 3694 m above sea level, using in situ taxonomic recognition, ecological indices and bioinformatic profiling of the “resistome” of the DREB, NAC and MYB transcription factor families, whose profiles were compared with those of the commercial species S. lycopersicum using an exact Poisson test with Holm correction. Four wild species were identified: S. corneliomulleri, S. habrochaites, S. pimpinellifolium and S. pennellii. Ecological analysis revealed that the Lurín basin exhibited the greatest diversity (H’ ≈ 1.07), whereas the Rímac basin was impoverished (H’ ≈ 0.20). Genomic comparisons quantified in S. lycopersicum a 45% reduction in DREB genes and a 30% reduction in NAC genes relative to S. pennellii, the species with the largest repertoire in both families. S. corneliomulleri stood out as a potential reservoir of abiotic resistance with 3095 MYB genes, and S. pennellii showed the greatest representation in the families associated with salinity and drought. Interspecific differentiation was concentrated in the two families linked to the drought response. These findings identify wild populations in Lima as critical reservoirs for reintroducing resilience into cultivated tomato in the face of climate change and its impact on food security.