Plant Health Care, the alternative farm chemicals group, has signed up a third agribusiness major to its flagship anti-pest product – and signalled that further tie-ups may be in the pipeline.

Germains Seeds Technology, part of Associated British Foods, is to help develop Plant Health's Harpin chemical, with the aim of including it on dressing on it next generation of sugar beet seed.

The deal, which adds a further 10m acres of crops to Harpin's potential market, "is the first of several" fresh tie-ups Plant Health is pursuing to exploit the protein, which stimulates plants' own immune systems to fight pests such as nematode worms.

"This deal… clearly demonstrates the breadth of potential partners available for the commercialisation of [the company's] technologies," Plant Health said.

The group has already signed up Monsanto over applications to canola, corn, cotton and soybeans, and in July unveiled an agreement with Syngenta over including the product in generalist glyphosate weedkillers.

'Ascent to mainstream'

The deal with Germains, which has market shares for sugar beet seed of more than 35% in Europe and of 40% in the US, "provides further evidence of Harpin's ascent to the agrichem mainstream", Evolution analyst Philip Sparks said.

It took to 70m-90m acres the crop area on which Harpin could be applied, at a margin estimated at $0.50 an acre.

Some 50m acres could be reached by 2015, implying Plant Health earnings of 10p per share by then, he added, restating a "buy" rating on the company's shares and a target of 150p.

The stock closed 1.7% lower at 116p in London.