The Use of Australian Native Solanum as Rootstock for Tomato (Solanum lycopersicum L.) and Eggplant (Solanum melongena L.) Production: A Case Study with Solanum symonii H.Eichler

Solanaceous species are crops of economic importance in Western Australia that also face challenges from poor soil quality, a warming and drying climate, and soil-borne pathogens. This study explored the potential of Solanum symonii, a native Western Australian species, as a rootstock for tomato (Solanum lycopersicum) and eggplant (Solanum melongena) to enhance their resilience to local growing conditions. There are no prior published reports of native Western Australian species as rootstock in commercial horticulture. Propagation trials using seeds and cuttings of S. symonii were conducted, followed by grafting trials to evaluate compatibility with tomato and eggplant scions. Grafted plants were grown in a greenhouse and subsequently transferred to a high tunnel for fruit yield assessment. Graft survival, leaf chlorophyll content, and fruit yield were measured. Results demonstrate long-term graft compatibility, despite 50% early graft failure, with no adverse effects on subsequent fruit production. These findings suggest S. symonii has potential as a novel rootstock for solanaceous crops in Western Australia if early graft survival can be improved. The results demonstrate the need for further research on S. symonii and other native Australian Solanum as rootstocks to address biotic and abiotic challenges in horticulture.