unlocking the potential of heirloom tomatoes as rootstocks for sustainable greenhouse tomato production

Heirloom tomatoes (solanum lycopersicum l.) are highly valued for their superior quality, yet their potential as rootstocks remains largely unexplored. the experiment followed a 4×2factorial arrangement consisting of four rootstock levels (the commercial hybrid 'parisa', two heirloom rootstocks, and a non-grafted control) and two scion cultivars ('sylviana' and 'e15b.50115'). under this design, grafting success, vegetative vigor, yield, and fruit quality were assessed. the commercial rootstock 'parisa' maximized total yield, reaching 1316.93 g/plant, while the heirloom1 rootstock achieved a competitive marketable fruit percentage of 84.28%, comparable to the commercial hybrid. beyond these primary yield components, heirloom rootstocks significantly improved fruit quality attributes compared to non-grafted controls, specifically increasing fruit firmness, titratable acidity (up to 4.12 ml), and total soluble solids (up to 4.87 °brix), as well as enhancing morphometric traits such as larger fruit diameter (6.31 cm) and increased pericarp thickness. these reproductive and quality benefits were supported by enhanced vegetative vigor, with heirloom1 producing the tallest plants (279.67 cm) and the highest root dry weight (13.72 g). consequently, these findings demonstrate that while commercial rootstocks excel in total biomass production, heirloom rootstocks provide a superior strategy for optimizing marketable quality and physiological performance in greenhouse production. these findings demonstrate that locally adapted heirloom genotypes are valuable, under-utilized genetic resources. their use as rootstocks offers a strategy to improve plant vigor, fruit quality, and sustainability in high-value greenhouse tomato production systems.