Outbreaks of Escherichia coli O157:H7 infections have been linked increasingly to leafy greens, particularly to lettuce. We present here the first evidence that this enteric pathogen can multiply on the leaves of romaine lettuce plants. The increases in population size of E. coli O157:H7 in the phyllosphere of young lettuce plants ranged from 16- to 100-fold under conditions of warm temperature...

Fresh-cut leafy greens contaminated with Escherichia coli O157:H7 have caused foodborne outbreaks. Packaging conditions, coupled with abusive storage temperatures of contaminated lettuce, were evaluated for their effect on the potential virulence of E. coli O157:H7. Shredded lettuce was inoculated with 5.58 and 3.98 log CFU E. coli O157:H7 per g and stored at 4 and 15°C, respectively, for up to...

Contamination of food crops by the human pathogen Salmonella is a food safety threat worldwide. Though using treated wastewater for irrigation is a sustainable practice, it may introduce trace levels of Salmonella that may contaminate food crops. Salmonella could develop resistance to antibiotics present in wastewater. The overall goal of the project is to increase the understanding of the publ...

The use of ozonated water as a sanitizer to extend the shelf life of fresh-cut lettuce and the effect on the antioxidant constituents (polyphenols and vitamin C) were investigated. Fresh-cut iceberg lettuce (Lactuca sativa L.) was washed at 4 degrees C using three different ozonated water dips [10, 20, and 10 activated by ultraviolet C (UV-C) light mg L(-1) min total ozone dose], and the dips w...

background and aims: the causal agents of viral lettuce big vein disease are two viruse, lettuce big vein associated virus (varicosavirus) and mirafiori lettuce virus (ophiovirus). these viruses have coat proteins of similar size but have different morphologies and serologically unrelated.the purpose of this study was to distinguish and detect lbvav and milv in lettuce fields in tehran province...

Background and Aims: The causal agents of viral lettuce big vein disease are two viruse, Lettuce big vein associated virus (Varicosavirus) and Mirafiori lettuce virus (Ophiovirus). These viruses have coat proteins of similar size but have different morphologies and serologically unrelated.The purpose of this study was to distinguish and detect LBVaV and MiLV in lettuce fields in Tehran Province...

Objective: According to the traditional medicine,lettuce can affect nerve conduction velocity and memory. So, to investigate the effect of lettuce seeds extract on body activities, lettuce seeds were used. Materials and Methods: In the present study, the effects of lettuce (Lactuca sativa) seeds extract consumption (in drinking water) on T4 level...

babol local lettuce as a landrace in mazandaran, has cultivated for many years. local lettuce is a mixture of different genotypic and phenotypic forms which affects its marketability. it was purified by individual selection method during a three year priod (1998-2000) based on the selection for characteristics such as shape of bush, closed pome high yield, good marketability and resistance to d...

In this study, we determined the effects of raising seedlings with different light spectra such as with blue, red, and blue + red light-emitting diode (LED) lights on seedling quality and yield of red leaf lettuce plants. The light treatments we used were applied for a period of 1 week and consisted of 100 mmol m s of blue light, simultaneous irradiation with 50 mmol m s of blue light and 50 mm...

Colorado potato beetles have been reared successfully through 12 generations on artificial diets containing either 2.5% potato leaf powder or 2.5% lettuce leaf powder/0.75% potato leaf powder. For all but one of the treatment groups, the mean duration of each of the four larval stages was between 0.8 and 1.5 days longer than the durations exhibited by control beetles that had been fed on potato...