There have already been some successes in unravelling the basic genetics of weeds.
Arabidopsis thaliana, or thale cress was the first plant to have its genome read. Under the auspices of the Arabidopsis Genome Initiative its tiny genome was published in 2000. The weed grows quickly, even in seemingly barren conditions and there is a prolific seed production. Studying the Arabidopsis genome is already yielding results. Early achievements were discovering how to double the yield of oilseed rape and protecting wheat from disease.

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Oryza sativa, or red rice weed has been another target of recent studies. Scientists discovered that the pest is able to absorb more nitrogen than the rice that's cultivated for food. So when nitrogen-rich fertilizers are spread over fields, they take most of the nutrients and grow bigger than the useful rice varieties.
Now the hunt is on for the genes responsible for this nitrogen fixing. If they are located, scientists could perhaps either turn them off or use the knowledge to improve the nitrogen fixing capabilities of rice. That in turn could produce a much bigger yield.