Alfalfa Plants

     The third method of obtaining spider silk is more complicated than the previous two; it involves genetically altering alfalfa plants so that they can produce the special spider silk proteins. Plants naturally produce proteins in the first place, so adding the spider silk protein is not much of a change for them. The advantage to this method is that it can be done at a large scale. Thousands of acres could be used to grow alfalfa plants. The image shows young alfalfa plants.

The drawbacks to this method are also plentiful.
  • Genetically altered alfalfa has a hard time being approved by the FDA and the USDA. 
  • The state of California has already turned down other forms of genetically altered alfalfa 
  • The alfalfa grows well in greenhouses, but it has trouble surviving outside

    When the alfalfa is genetically altered, the gene that tells the plants to create the protein becomes part of their genetics. This also leads to problems. 

  • Alfalfa plants can treat the gene as a virus and shut it down, causing it to stop protein production
  • The gene gets passed down to future generations, but the gene is only active in about half of the plants
  • Taking into account that in every generation of alfalfa plants, only about half have an active gene and that some of them might shut down the gene, there is a possibility that only ten percent of the plant will actually produce the spider silk protein (Lewis)
  • Ten percent is not a very effective outcome, but considering the relatively cheap cost to produce, when compared to the bacteria process, it might be a possibility