A new biological botrytis fungicide that leaves no residue and has no withholding period has been released for commercial development.

After successful field trials over three years, Sentinel has received approval from agricultural certification body Bio Gro.

Developers Agrimm Technologies say the field trials and evaluation showed the product had "every indication of being as robust as conventional chemistry in protecting grapes from botrytis".

There is a $30 million market in the wine industry for products that fight the fungus. Strawberries, tomatoes, peppers, cucumbers and flowers are also affected.

Sentinel is the first product of its type to be registered here and is one of the first commercial releases from the Bio-Protection Centre at Lincoln University, although it was developed for commercial use privately.

Agrimm of Christchurch said the product was already attracting strong interest from grape growers.

Publicly-listed Botry-Zen is also developing a biological control product against botrytis. Botry-Zen is hoping to get EU and US registration for its product within two years.

Sentinel uses a new strain of a beneficial fungi to colonise leaves, flowers and fruit bunches and prevent botrytis from gaining a foothold.

Distributor Key Industries said it was "very big news" for the wine industry.

"Sentinel is not only organic, it can be applied at times when other fungicides cannot be used because of withholding periods," Key managing director Frank Visser said.

"It has no negative effects on vintification, leaves no residue in wine and leaves no coloured residue on the grapes."

Visser said it was cost-effective in comparison with other fungicides.

Agrimm's John Hunt said field trials had already begun to get registration in Australia.

It would take a season of successful trials plus a bureaucratic process that would last eight to 18 months before the product could be sold across the Tasman.

"Realistically, we are looking two to three seasons away," he said.

- NZPA