World's biggest plant discovered off Australian coast

Image source, Rachel Austin

A plant that is three times the size of Manhattan has been discovered off the coast of Australia.

Scientists used genetic testing to determine that a large underwater meadow in Western Australia is one plant.

It is thought to have been spread from a single seed.

Researchers from the University of Western Australia said that the seagrass covers about 200 sq km.

The team stumbled upon the discovery by accident.

They wanted to understand the genetic diversity of the ribbon weed, which is found along parts of Australia's coast.

Researchers collected shoots from across the bay and looked at 18,000 genetic markers to create afingerprint from each sample.

They wanted to find out how many plants were in the meadow.

Jane Edgeloe, the study's lead author, said the answer blew them away.

One plant has expanded over 180 km in Shark Bay, making it the largest known plant on Earth.

Image source, Angela Rossen

The plant has grown in locations across the bay with wildly variable conditions.

It appears to be really resilient, experiencing a wide range of temperatures and salinities plus extreme high light conditions, which together would typically be highly stress for most plants, said Dr Elizabeth Sinclair, one of the researchers.

The species grows like a lawn at a rate of up to 35 cm a year. Researchers estimated it took 4,500 years to sprawl to its current size.

The research was published in a journal.