Plants are the backbone of all life on Earth. They produce oxygen and help control our climate. They are in our food, fuel and medicine.
For the first time, an A-to-Z study of the plant kingdom has been carried out at the Royal Botanic Gardens, in Kew, West London.
Researchers found more than a fifth of the world's plants are at risk of extinction. The main threats are deforestation, loss of habitat, disease and invasive plant species.
The study identified almost 400,000 unique plant species at risk.
But it is not all bad news. The report also says that more than 2,000 new plant species were discovered last year.
Presenter: Laura Kyle
Colin Clubbe - Head of conservation science at the Royal Botanic Gardens
Maximilian Weigend - Professor of plant biodiversity at Bonn University
Susan Leopold - Executive director of United Plant Savers
Source: Al Jazeera