Effects of contaminated irrigation water on the fate of salmonella typhimurium on rosemary and barley cultivated on contaminated fields

Abstract

Animal wastes in the form of manure frequently contain enteric pathogenic microorganisms and land spreading
can lead to pathogen entry into the food chain. Therefore, the aim of the present study was to determine the
persistence of Salmonella enterica serovar typhimurium in soil, and on barley and rosemary plants. We
observed that Salmonella typhimurium persisted for an extended period of time (203 to 231 days), and could be
detected on infected vegetative parts of the rosemary and barley plants even after desiccation. After
approximately two months, the colony morphology displayed a mucoid and rugose phenotype. Smooth colony
morphology was acquired following incubation in nutrient broth and upon isolation from the digestive tracts of
mice that had been challenged orally with stressed S. typhimurium. S. typhimurium was neither isolated from
vegetative parts formed after plant contamination, nor from barley seeds and rosemary flowers.