Poison plant could help to cure the planet

The jatropha bush seems an unlikely prize in the hunt for alternative energy, being an ugly, fast-growing and poisonous weed. Hitherto, its use to humanity has principally been as a remedy for constipation. Very soon, however, it may be powering your car.

Almost overnight, the unloved Jatropha curcushas become an agricultural and economic celebrity, with the discovery that it may be the ideal biofuel crop, an alternative to fossil fuels for a world dangerously dependent on oil supplies and deeply alarmed by the effects of global warming.
The hardy jatropha, resilient to pests and resistant to drought, produces seeds with up to 40 per cent oil content. When the seeds are crushed, the resulting jatropha oil can be burnt in a standard diesel car, while the residue can also be processed into biomass to power electricity plants.

As the search for alternative energy sources gathers pace and urgency, the jatropha has provoked something like a gold rush. Last week BP announced that it was investing almost