Agrobacterium (Genes into Plants)
A soil bacterium that naturally inserts some of its DNA into plants was disarmed and used in 1983 to put new genes into plant cells, the method behind most genetically modified crops.
Open in the interactive tree →The bacterium Agrobacterium tumefaciens causes tumours called crown gall by passing a piece of DNA from its Ti plasmid into plant cells; the plasmid was identified in the early 1970s. In 1983 Mary-Dell Chilton's group and others made the first genetically engineered plants, tobacco, after removing the genes that cause tumours while keeping the bacterium's ability to insert DNA. Field trials followed in 1986, virus-resistant tobacco was grown in China from 1992 and the Flavr Savr tomato was approved in 1994, and by 2016 genetically modified crops covered 185.1 million hectares, about 12% of the world's cropland.
Prerequisites
- Germ Theory1861A plant-disease germ was turned into a gene carrier.
- Genetic Engineering1973Genes can be cut, joined and copied in the lab.
Unlocks
- Genetically Modified Crops1996Most genetically modified crops are made with Agrobacterium as the gene carrier.