The plant microbiome company Indigo has raised $100 million in its third round of funding, led by the Alaska Permanent Fund. Indigo was formed at VentureLabs, the start-up-generating arm of Flagship Ventures. The company develops beneficial microbes that it discovers inside plants. The microbes can increase yield by conferring resistance to stresses such as water scarcity, the company claims. It just launched a coated cottonseed that improves water efficiency. A wheat product is next.