Wolfgang Stuppy, scientific curator at the Botanic Garden of Ruhr-University Bochum in Germany, who helped organize and source seeds for the pavilion when he worked at Kew, remembers the excitement at the time, because "it was such an extraordinary idea" and made people more aware of the need to conserve plants.

"For the Millennium Seed Bank to be represented at the World Expo in Shanghai was just incredible," Stuppy said. "Internationally, everyone learned about the seed bank's partnership, everyone learned about the importance of seeds and seed banking and they learned about our partners in Kunming. They also learned that China is actually doing seed banking, which very few countries do, so the country is really ahead in that respect."

Stuppy said the Shanghai expo was "a huge stage to get our message across and attract important people who could help us further .. it was only possible because of the collaboration with our Chinese partners."

Loscertales said, "For a fast-growing and constantly evolving city, the expo was an endeavour that allowed the Shanghai government to catalyse renewal in the heart of the city, creating new green spaces and allowing the development of cultural venues."

Almost a decade later, the legacy of the expo can be seen in Shanghai's urban transformation and economic and cultural development.

Part of the site used for the event is now occupied by the World Expo Museum, which opened in 2017 and is the only such institution in the world entirely dedicated to the history of expos. The museum was approved by the BIE.

Loscertales said: "Shanghai is undoubtedly one of the greatest examples of a city transformed by a World Expo. The beautiful parks along the Huangpu River, the museums, including the World Expo Museum, the city's unrivaled transportation network and its cosmopolitan outlook - all of these were made possible or buoyed by Expo 2010."

The event was a "diplomatic success story" for China as a whole, according to Loscertales, as it improved relations with countries worldwide.

"As a mega-event gathering countries from around the world in Shanghai, Expo 2010 both reflected and anticipated China's ambition to build a community with a shared future for humankind," he said.

Experts believe the expo reinforced Shanghai's status as an important economic, financial and foreign trade center.

Mitter, from Oxford University, said it was very important for Shanghai to try to emphasize its legacy as a gateway to the world.

"Much like the Olympics, such expos are chosen through an international process. Therefore, Shanghai being given this status was a big indication that China was being recognized as a country very much in the first tier of international trade and commerce," he said. Mitter added that the next stage in the country's development will be moving from an export powerhouse to developing a strong and self-contained economy.