A common fungus has been turned into a super weapon that kills the varroa mite, which has devastated New Zealand bees.

Ruakura Plant and Food Research scientist Dr Mark Goodwin developed a metarhizium fungus-based product which is effective against the bee-killing varroa mite.

The Waikato Times reported the new product should be ready for market, through the United States company Becker Underwood, next year.

The product was not harmful to bees and would replace three synthetic chemical treatments. The mite, which feeds on the pupa of bees, arrived in New Zealand nine years ago.

Dr Goodwin, a finalist in the Kudos science awards in Hamilton last week, said the metarhizium fungus came in thousands of varieties and was well known around the world for its insect-killing properties.

He had found the longer it was used, the more mites it killed. His success rate, over time, was about 90 percent.

How much the new product would be worth to the economy was difficult to estimate, said Dr Goodwin.

Biosecurity NZ said the pollination of crops was worth many times the value of honey and other bee products.