"More and more people think of me as a businesswoman," said Zhang, professor of Fujian Academy of Agricultural Sciences. "But I prefer to be called a scientist."

Zhang, is one of the country's top researchers studying mites which prey on pest mites.

Pest mites destroy millions of crops throughout the world. In China, peasants use pesticide to kill spider mites and rust mites. Overuse of such chemicals, however, is creating food safety issues and environmental deterioration. Zhang's method of biological control is an alternative solution to these emerging problems.

Zhang began to study mites 27 years ago. In the mid-1990s, she introduced a foreign predatory mite named Amblyseius cucumeris Oudemans into China. Its purpose was to kill other mites which were destroying crops.

After years of state-sponsored research, she succeeded in developing a set of procedures for breeding the predator mite. Zhang's discovery enabled mass production, packaging, preserving, transportation and field application of the microscopic creatures.

Zhang first unleashed the predatory mites on bamboo hills in north Fujian Province in southeast China in 1998. They successfully killed the mites that were eating the bamboo, thus saving the plant.

Since 1999, Zhang expanded her biological control method to more than 20 species of crops including citrus, tea, hop, cotton and apple.

For those achievements, she was awarded second prize at China's2008 State Top Scientific and Technological Awards on Friday.

Over the past 10 years, her bio-control method has been used on191,000 hectares of land in more than 20 Chinese provinces. It helped reduce the use of pesticides by more than 3,200 tons and saved 870,000 peasants more than 180 million yuan on pest control.

According to Zhang, the greatest obstacle in China was and still is persuading peasants to get rid of the entrenched practice of using pesticides.

"They don't trust you and they even throw the free predators away."

Eight years ago, in a desperate bid to gain peasants' trust, Zhang began selling mites instead of giving them away. She then promised to pay for all the losses if the mites failed. In 2005, she set up Fujian Yanxuan Biocontrol Technology Company, China's first mite-breeding enterprise.

"The company has paid well and proved the most effective way to accelerate the commercialization of predatory mite breeding," said Zhang. "I hope to turn it into the biggest mite breeding company in China in a few years."

The company now produces 800 billion predatory mites per year. They are sold around the world on demand.

"The predators have been exported to Holland and Germany since February of last year," said Zhang. So far, 30 batches delivered to the two countries equaled about 700 million mites. "We are going to export them to US, too."

Zhang has earned nationwide and even worldwide acknowledgement for her mite research. She, however, remains unsatisfied with the relatively slow dispersion of her "brilliant" buddies in comparison with the dominant chemical control methods.

"Biological control can reduce the use of pesticides by 60 to 80 percent, increasing the produce value by five to ten percent. It also cuts production costs by about 70 percent," she said. "Why can't we further tap its market potential?"