New research could reduce the probability of E.coli in lettuce.
Scientists with the US Department of Agriculture have found the bacterium that causes food borne illness in humans, is more likely to contaminate lettuce when downy mildew is already present.
Downy mildew is a lettuce disease caused by a fungus-like water mold, and is one of the biggest problems lettuce growers face.
Microbiologist Maria Brandl has been investigating why so many E. coli outbreaks can be traced back to lettuce fields when E. coli sources are as diverse as undercooked beef, sprouts, raw dairy, shelled walnuts, fruits and vegetables.
Lettuce leaves are actually a harsh place for microbes to survive, but the epidemiological evidence is indisputable about how often lettuce is the source of E. coli contamination.
Brandl’s research has uncovered that lettuce that is bred to be resistant to downy mildew is also less likely to host the E. coli bacterium.
Brandl and her team are now trying to pinpoint the exact factors that cause the reduction of E. coli in the resistant lettuce, with hopes the genetic trait could be bred into lettuce varieties and thus lead to fewer cases of the food-borne illness.
The study is published in the journal Ag Research.
