GUANGZHOU, July 1 (Xinhua) -- During the Tang Dynasty (618-907), Emperor Xuanzong had a 7-day horse relay transport lychees from Guangdong in the south to the then capital Xi'an to satisfy the appetite of his favorite concubine Yang Yuhuan.
Today, the fruit takes less than a day to cover the same 1,700 kilometers, and thousands of tonnes go overseas every year.
Lin Bo, a fruit farmer in Guangdong's Maoming, pointed to a refrigerated truck being loaded with lychees. "They are bound for Singapore where they will arrive as fresh as they left Maoming," he said.
Maoming has been home to lychee plantations for over 2,000 years. Maoming lychees were perhaps the very fruit Emperor Xuanzong used to appease his lover. Now, the city produces one quarter of all China's lychees.
In Lin's orchard, workers sort and refrigerate the newly-picked fruit as trucks queue up outside waiting to be loaded. His market extends from Southeast Asia to North America, Australia and Europe. It is cold chain logistics that have made the difference.
"Last year, we exported about 40 containers. This year it'll be over 90," Lin told Xinhua. "It's more than a thousand tonnes."
According to China's ancient poets, once picked from the trees, lychees lose their color in one day, their scent in two days and taste in three days. But assisted by researchers from South China Agricultural University, Lin's fruit keeps its freshness for 35 days -- more than enough time to be shipped to Europe.
Cold chain is the mechanism which has given fruit growers access to China's vast e-commerce market.
Another Lin Bo was born in a village where everybody grew lychees, but few made a living from them. When the harvest came, villager chipped in to rent a truck, headed for a big city, and sold their fruit at the side of the road.
The better the harvest, the harder the sales. During the bumper years, the emperor's delicacy rotted beneath the trees.
Lin Bo started an online fruit store in 2011, and buyers have increased ever since. This year he has sold 40,000 crates, 20 times the amount he sold seven years ago.
The villagers don't need to worry about transportation or sales anymore. Freshly picked fruit packed with ice bags are carried by courier to major cities within 24 hours.
The once imperial tribute is now a summer snack for ordinary Chinese families and an important source of revenue for farmers.
According to the Maoming Municipal Fruit Bureau, the city has over 3,600 active online lychee sellers. The booming e-commerce has also encouraged the farmers to further improve their fruit varieties.