THE yellow-cyst nematode or golden worm (Globodera rostochiensis) was discovered in the United States in 1941 following a massive potato crop failure in the Long Island District of New York. Potato production dropped by 70 percent as the soil was infected by the golden worm. So massive a fall in potato production that the US Department of Agriculture declared the nematode the most dangerous potato pest ever discovered.

The golden worm has