Predatory mites reduce pesticide use in China

Farmers in east China's Fujian Province are not worried about pesticide residues, thanks to pathogen-carrying predatory mites.

The multi-target biocontrol system, developed by Zhang Yanxuan of Fujian Academy of Agricultural Sciences, can reduce pesticide use by up to 50 percent.

Zhang started breeding mites -- a small invertebrate closely related to spiders -- in 2005. His company now has a yearly production capacity of 800 billion predatory mites, used on over 20 crops including citrus, apples and cotton. The critters have been exported to the Netherlands, Germany and Canada.

As their natural enemy, these predatory mites prey on red spider mites, rust mites and other pests, but proved useless against pest insects, which forced farmers to return to pesticide.

After years of experiments, Zhang has succeeded in infecting his mites with a insect-killing fungal pathogen.

"The entomogenous fungus attached to hairy predatory mites can infect and kill various kinds of insects but is harmless to the mites themselves, humans and animals," Zhang said.

Zhang has invented a patent container for releasing mites dusted with the pathogens in the field.

"We've used the method on more than 1.2 million hectares, in over 20 provinces," Zhang said. Endi