Scientists favour particular animals, insects or bacteria over others when it comes to experimental research. These dependencies are not decided on a whim, but are the result of learning what features yield the most practical results in experimentation. Rat models are very popular in cancer research, for example — they are rather prone to tumours once past a certain age. Slime moulds and fruit flies are useful in genetics since they have simple genomes and reproduce very quickly, providing the researcher with many generations in a short time span — perfect for figuring out genetic change over time.
The modest, white-flowered arabidopsis (Arabidopsis thaliana, also known as wall cress) is the fruit fly of the plant world. With a relatively short life cycle and a small genome, this Eurasian native member of the mustard family has been contributing to plant sciences for over 50 years.
Here are the features that make arabidopsis so useful for research — firstly, it’s a small plant, maturing at about 20 centimetres; it doesn’t need a lot of fancy nutrients, thus is cultivated in laboratories. It’s also an ephemeral plant, which means that it finishes its entire lifecycle within a mere six weeks, as opposed to perennial plants that persist year after year. Since every plant also produces abundant seeds, cultivation of modified laboratory strands is easy as well.
Little arabidopsis was the first plant to have its entire genome sequenced, and today extensive data is available on its genetic map, gene structure, gene expression, DNA and many other features. Furthermore, there are dedicated stock centres that carry seeds and specific mutant lines of the plant. There are at least seven books entirely dedicated to different aspects of this plant and its research.
The funny thing is that arabidopsis is basically a weed — it has no significant agricultural value and it’s not even particularly decorative. However, because scientists know so much about this model plant, they are able to use this knowledge for reference when working on plants that we may actually want to eat.