WASHINGTON — The Obama administration on Friday will announce the latest in its scientific “moonshots,” this one in the red-hot field of microbiomes — the trillions of micro-organisms in places like soil and the human gut.

The new National Microbiome Initiative is intended to create scientific tools, discoveries and training techniques that could advance efforts to cure asthma and depression, clean up oil spills and even increase crop yields. The initiative will involve more than a dozen federal agencies, top universities, major philanthropies and corporate giants.

“This initiative is about connecting a lot of the threads and looking for common insights across different domains,” John P. Holdren, the director of the White House Office of Science and Technology Policy, said in an interview. “There’s just an incredible amount of excitement about this.”

Microbiomes have become the focus of intense study and public interest. The microbes that live inside the human body, for example, play important roles in health, like fighting diseases, helping children develop and maintaining a balanced immune system. Microbiomes in the oceans produce half of the oxygen we breathe.