Tan Baolin went into a vegetable greenhouse. "Now, it's music time," he said and pushed a button on a green instrument. The greenhouse filled with a dull buzz immediately.

"You may think it's noise, but the vegetables like it. They listen to it one hour in the morning and one in the afternoon every day, and the output increases by 20 percent," Tan told Beijing Daily.

Beijing will hold its first Agricultural Carnival in Changping district on March 23, and more than 10 new agricultural techniques will be on display. The audio stimulating instrument is one of them.

The instrument releases sound waves in a specific frequency, which work to stimulate the vegetable roots and speed the process of metabolism, according to a person in charge of the exhibition.

Tan said strawberries growing with the music become mature 15 days sooner than ordinary ones, and become even sweeter.

Other techniques to be displayed include fog cultivation, which changes the nutrient solution into fog drops and help save water and prevent disease. Another technique is a carbon dioxide production instrument that replenishes carbon dioxide for greenhouse vegetables and boost production.

These techniques will be spread to the Beijing suburbs and help many farmers after the agriculture event.