From Halopedia, the Halo wiki
In early 2553, the UNSC's Office of Naval Intelligence began to grow irukan on the research facility Trevelyan in order to create a bioweapon against the Sangheili. The grain was to be genetically modified in an effort to make it indigestible to Sangheili. The Irukan grown would have been used to starve Sanghelios' population if ONI's plan of internal dissent failed. Trevelyan facility's director, Dr. Magnusson, noted that the genetically modified irukan would completely overwhelm the native strain in less than three years. In order to expedite the growth of the irukan crops, ONI asked the Huragok to create accelerating slipspace bubbles in which time elapsed faster than in normal space.
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