Shares in Plant Health Care poked their head above the clouds after the alternative agrichemicals group revealed a second deal with Syngenta for its flagship plant protection product, opening up a market estimated at 1bn acres.

Syngenta, the world's biggest farm chemicals group, had agreed to "evaluate and possibly develop" Plant Health Care's Harpin product as an additive to fungicides, insecticides and growth regulating sprays.

The deal comes four months after Syngenta agreed to develop and market Harpin for mixing with glyphosate, the generalist weedkiller for which the Swiss company is fighting to differentiate its brands from a mass of cheap alternatives produced by generic agrichemicals group.

And it aims Harpin at a larger potential market, with glyphosate applied to 200m acres worldwide, only a portion of the area reached by agrichemicals overall.

'Huge potential' 

Indeed, the deal opens up "the billion-acre global market", Evolution analyst Philip Sparks said, adding that he expected Plant Health products, in five years' time, to be actually deployed "over 100m acres of crops".

"And that figure will still have plenty of room to grow," he added, restating a "buy" rating on Plant Health shares, with a 150p target.

"It will be a few years before we can hope to see revenues from foliar applications, but the long-term potential is huge."

Plant Health also has deals for Harpin with Monsanto and sugar beet group Germain's Seed Technology.

Further collaboration? 

John Brady, the Plant Health Care chief executive, added that the deal could pave the way for further tie-ups between the company, which also has other products including a root improvement treatment, and Syngenta.

"We believe there are strong synergistic opportunities between the two companies' product lines," he said.

And the deal initially helped Plant Health shares soar 11% to 79p before the stock retreated to close at 71p, up 1.4% on the day.

The shares have, unlike those in other agriculture companies, failed to be revived by soaring crop prices, and have lost nearly two-thirds of their value this year.