User:MikeyYB/sandbox

One of the key issues concerning regulators is whether GM products should be labeled. Labeling can be mandatory up to a threshold GM content level (which varies between countries) or voluntary. A study investigating voluntary labeling in South Africa found that 31% of products labeled as GMO-free had a GM content above 1.0%. In Canada and the United States labeling of GM food is voluntary, while in Europe all food (including processed food) or feed which contains greater than 0.9% of approved GMOs must be labelled. In the U.S. state of Oregon., voters voted down Measure 27, which would have required labeling of all genetically modified foods. Japan, Malaysia, New Zealand, and Australia require labeling so consumers can exercise choice between foods that have genetically modified, conventional or organic origins.

Agrobacterium tumefaciens-mediated transformation is another common technique. Agrobacteria are natural plant parasites as they insert genes into plants and cause them to eventually die. Their natural ability to transfer genes provides another engineering method. To create a suitable environment for themselves, these Agrobacteria insert their genes into plant hosts, resulting in a proliferation of modified plant cells near the soil level (crown gall). The genetic information for tumor growth is encoded on a mobile, circular DNA fragment (plasmid). When Agrobacterium infects a plant, it transfers this T-DNA to a random site in the plant genome. When used in genetic engineering the bacterial T-DNA is removed from the bacterial plasmid and replaced with the desired foreign gene. The bacterium is a vector, enabling transportation of foreign genes into plants. After the insertion of the T-DNA, the plant has to undergo a callus stage to heal its outer layer of cells from the agrobacterium’s invasion. This method works especially well for dicotyledonous plants like potatoes, tomatoes, and tobacco. Agrobacteria infection is less successful in crops like wheat and maize.

Wheat
Wheat has been genetically modified for desirable traits such as drought resistance, B. t. kind (it is known as the Bacillus thurengensis), herbicide glyphosate, and others. For instance, genetically modified Pseudomonas putida WCS358r can affect wheat to modify it into an anti-fungal variety. Placing the modified organism on the rhizosphere of the plant will achieve this. Methods of genetic modification for wheat have low success rates.