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Over the last decades, leafy greens were involved in numerous Salmonella outbreaks. In order to control plant contamination, it is necessary to understand pathogen behaviour both on plant and in soil of producing fields. The objectives of this study were to monitor the growth and survival of Salmonella Typhimurium on lettuce leaves (uncut and shredded) stored at 4 and 22°C for up to 14 days and in soil (manure-amended and sterile) stored at 5 and 25°C for 42 days. Lettuce samples were inoculated with 1.5 x 106 CFU g-1 of the microorganism and enumerated following storage for 0, 2, 6, 10, 14 days when held at 4°C and after 0, 2, 3 and 7 days when held at 22°C. Soil samples were inoculated with 5 x 107 CFU g-1 of S. Typhimurium and enumerated after storage at 5 and 25°C at days 0,7,14,21,28,35 and 42.The results showed that at the end of 4°C storage, populations of S. Typhimurium on uncut and shredded lettuce declined approximately one log CFU g-1, however, at 22°C populations of the microorganism increased approximately 2 and 3 log CFU g-1 on uncut and shredded lettuce, respectively within 3 days. In addition, S. Typhimurium counts were found to be significantly higher on shredded than uncut lettuce stored at 22°C. In soil, population density of S. Typhimurium was found to decrease over time. The greatest and fastest decline in level of microorganism was recorded in manure-amended soil within 21 days of storage at 25°C, meanwhile, in sterile soil stored at 5°C the pathogen showed the lowest decrease and remained detectable up to end of examination (42 days). Significantly higher levels and survival of S. Typhimurium were detected in sterile soil than manure-amended soil and at 5°C than 25°C storage. [ABSTRACT FROM AUTHOR]