Paris - An enduring myth among amateur gardeners - that wheat grains found in the ancient tombs of Egyptian mummies can miraculously flower after millennia underground - has been shot down by science.
The legend of so-called mummy wheat spread across Europe in the early 19th century after Napoleon's army discovered relics of ancient Egypt during its ill-fated expedition to the Nile.
Within a few decades, the European press was gripped by reports that grains discovered in tombs up to 6 000 years old were found to have fantastic powers of regeneration, thanks to the arid conditions in which they had been stored - and, who knows, to some mystical power of the Pharoahs.
The seeds were said to be so fertile that they could yield as many as seven fat ears of wheat, a figure that chimed in nicely with biblical numerology.
At the height of the craze, so-called mummy wheat was sold for nearly $100 for 10 grains at today's prices.
The truth, though, is somewhat less exciting, the British weekly New Scientist reported on Thursday.
Many cereals can be stored for centuries, provided they are of good quality, are partially dried and kept in stable, chilled conditions and in low humidity.
But repeated attempts to resuscitate mummy wheat in the laboratory have failed, yielding only decay and mould.
Meanwhile, a killer blow to the tale has come from the Royal Botanic Gardens in Kew, London, which used a sophisticated computer model to calculate the potential longevity of mummy wheat.
The model, by John Dickie at the Gardens' Millennium Seed Bank, is based on the assumption that mummy wheat would deteriorate at a similar rate to modern grains.
His model for the storage conditions comes from the well-studied tomb of Nefertari, the favourite wife of Ramses II, who lived in the second millennium BC, New Scientist said.
The tomb's relative humidity is only 16 percent, which is excellent for seed storage.
The bad news: even though the tomb is located deep within rock, its temperature fluctuates from 16 to 28,5&C (60,8-83,3 F).
Pharonic power or not, this wide variation is disastrous for long-term grain fertility, says Dickie.
Even if the grain was of the highest quality, and the temperature remained constant at 167&C (60,8 F), perhaps one grain in a thousand could still germinate after 236 years.
And with the temperature hitting the high 20s, the grain would all be dead in just 89 years, he calculates. - Sapa-AFP