Recovery of Salmonella enterica Newport Introduced through Irrigation Water from Tomato (Lycopersicum esculentum) Fruit, Roots, Stems, and Leaves

• Published in: HortScience Vol. 45; no. 4; pp. 675 - 678
• Main Authors: Hintz, Leslie D, Boyer, Renee R, Ponder, Monica A, Williams, Robert C, Rideout, Steven L
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Society for Horticultural Science 01.04.2010
• Subjects: Agronomy. Soil science and plant productions; animal pathogenic bacteria; bacterial contamination; Biological and medical sciences; developmental stages; disease outbreaks; food contamination; food microbiology; food pathogens; fruits (plant anatomy); Fundamental and applied biological sciences. Psychology; irrigation water; leaves; plant development; roots; Salmonella enterica subsp. enterica serovar Newport; serotypes; Solanum lycopersicum var. lycopersicum; stems; tomatoes; uptake mechanisms; vegetable crops; Virginia; Newport; Irrigation; Vegetables; Horticulture; Climacteric; Fruit vegetable; Irrigation water; Tomato; Recovery; Stem; Growth chamber; Outbreak; Salmonella newport; Dicotyledones; Pathogenic; Angiospermae; Lycopersicon esculentum; Water engineering; Bacteria; Solanaceae; C3-Type; Enterobacteriaceae; Vegetals; Root; salmonellosis; environmental growth chamber; Plant leaf; roots; leaf; foodborne illness; Vegetable crop; Vegetative apparatus; Environment; Spermatophyta
• ISSN: 0018-5345; 2327-9834
• DOI: 10.21273/hortsci.45.4.675

Tomatoes have been associated with numerous outbreaks of salmonellosis in recent years. Trace-backs suggest tomato fruits may become contaminated during preharvest. The objective of this study was to determine the potential for Salmonella enterica serotype Newport to be internalized into the roots, stems, leaves, and fruit of red round tomato plants through contaminated irrigation water at various stages of plant development. Tomato plants were irrigated with 250 or 350 mL (depending on growth stage) of 7 log CFU·mL–1 S. Newport-contaminated irrigation water every 7 days. Roots, stems, leaves, and two tomato fruit from plants irrigated with S. Newport or water (negative control) were sampled for contamination at five stages of growth. Twenty-five of the 92 total samples taken from plants irrigated with S. Newport were confirmed positive (serovar specificity was not evaluated). Sixty-five percent of confirmed samples were roots, 40% were stems, 10% were leaves, and 6% were fruit. There was a significant difference in the presence of S. enterica according to tissue sampled (roots > stems > leaves, and fruit) (P < 0.05) and no association between growth stage and contamination (P > 0.05). Contamination of tomato fruit with S. Newport introduced through irrigation water is low because a high level of persistent contamination of a plant in the agricultural setting is unlikely.