Harnessing the crop wild relatives in genetic improvement of eggplant, potato and tomato

The genus Solanum encompasses economically significant crops, including tomato, potato and eggplant. Descending the taxonomic hierarchy from family to genus, species, subspecies, and variety is associated with a decrease in genetic diversity and an increase in homozygosity. Likewise, prolonged selection of plants favouring yield traits over many generations has narrowed the genetic variation within cultivars; this renders these cultivars susceptible to the impact of climate change and evolving pest and disease pressure. Harnessing the genetic variability present in crop wild relatives within the genus Solanum, focusing on important traits such as insect resistance, disease resistance, abiotic stress tolerance, yield enhancement, and nutritional quality can address the problem of food and nutritional security. Despite the promising traits in wild species, several barriers exist to incorporate traits from wild species to cultivars. This review discusses commercially important identified traits from the wild relatives of potato, tomato and eggplant, barriers in hybridization and method to overcome these barriers. Exploitation of the important traits from wild relatives holds substantial potential to address current and future challenges in Solanum crop improvement, ensuring food security and agricultural sustainability in a changing global environment.