One problem is that viruses cannot be killed by fungicides and other agrochemicals.

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Historically, firms such as Monsanto and Syngenta, which had their origins in agrochemicals, saw farmers, not shoppers, as their main customers.

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BASF, one of the world's largest producers of agrochemicals, saw 9% growth last year in agricultural sales, including 16% growth in Asia.

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Now Aventis is testing the idea of selling its agrochemicals unit.

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CropScience was formed from the merger of Bayer's existing agrochemicals business with the one it bought from Aventis (nyse: AVE - news - people ).

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Also evident is the impact of the European Common Agricultural Policy (CAP) in the 60s and 70s that witnessed the intensification of farming powered by the widespread use of agrochemicals.

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They were convinced that the overwhelming incidence of illness, birth defects, and cancer in their neighborhood was due to the amount of agrochemicals being sprayed on the fields adjacent to it.

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Likewise, although Dow Chemical and DuPont have strong agriculture divisions, companies specializing in agrochemicals and biotech crops increasingly stand alone: look at Monsanto and Syngenta , both of which were spun off from pharmaceuticals firms.

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The site produced agrochemicals including pesticides and herbicides.

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But it should fit cleanly with Bayer's agrochemicals division, creating the world's third-largest herbicides business and allowing it to compete more evenly with biotech crop and agrochemicals giants Monsanto (nyse: MON - news - people ) and Syngenta (nyse: SYT - news - people ).

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