The plant that pretends to be ill

A leaf damaged by mining moths (left) compared to one faking it (right).

A plant that pretends to be ill has been found growing in the rain forests of Ecuador. The plants feigns sickness to stop it being attacked by insect pests known as mining moths, which would otherwise eat its healthy leaves.

It is the first known example of a plant that mimics being ill, and could also explain a common pattern seen on plant leaves known as variegation.

The discovery is published in the journal Evolutionary Ecology.

Variegation is familiar to gardeners and affects many species of plant. Variegated plants have different coloured patterns on the leaf surface, produced by a variety of causes. One of the most common is when cells in the leaf lose chlorophyll and their ability to photosynthesise, appearing white. Canna 'Stuttgart' is an example of that type of variegation.

In theory, plants with variegated leaves should be at a disadvantage, because of this restricted ability to photosynthesise. But a chance discovery by a team of botanists suggests this may not be true after all. Instead, some variegated plants may be mimicking illness to avoid being eaten, putting themselves at an advantage.

"I was quite surprised," says Liede-Schumann. She believes that the plant essentially fakes being ill, producing variegated leaves that mimic those that have already been damaged by mining moth larvae. That deters the moths from laying any further larvae on the leaves, as the insects assume the previous caterpillars have already eaten most of the leaves' nutrients.

"The fact that there are both plain green and variegated leaves in the population indicates to me that both are useful in the long-term success of the species," says Liede-Schumann.

The reduction in a variegated leaf's ability to photosynthesise is likely to be more than offset by the benefits of not being eaten, the researchers believe, suggesting that variegation survives in wild plants because it confers a selective advantage.

Based on an article by Matt Walker, Editor, Earth Newsat the BBC.

Silence Of The Bees

The summer sound of buzzing bees is set to become rarer due to mystery plagues hitting hives around the world. The crisis threatens a disaster worse than global warming because bees are so vital to the food chain, experts warned yesterday.

Environment Minister Lord Rooker has already warned that, at present rates, honeybees could be extinct in Britain within a decade. Yet ministers are refusing to pump more money into research to find cures.

The looming disaster is detailed in Silence Of The Bees, a documentary due to be aired on the National Geographic TV channel next Tuesday. John Chapple, chairman of the London Beekeepers Association, believes the potential consequences could not be worse. He said: “Without bees, life as we know it will not exist.”

Scientists warned that the bees’ disappearance will hit a third of the world’s food crops, especially fruit and vegetables. Apples, soybeans, onions, cabbage and most berries and nuts are among 90 crops at risk if there are no honeybees to help pollinate them. Also threatened are plants used for cloth, such as cotton and flax, and those for animal feed, including oilseed rape and field beans.

Less feed for animals would affect meat and dairy products, pushing up prices and lowering availability. The impact would be felt up the food chain by birds which feed on fruit and by the predators which eat the birds.

Hives are being wiped out in America by Colony Collapse Disorder – and no one really knows what causes it. Tim Lovett, chairman of the British Beekeepers Association, said: “I hope we don’t have CCD here but, just like rock ’n’ roll and hamburgers, whatever affects America usually comes here. “In a month or two we will carry out a survey of our members to assess winter losses.”

Last winter a small number of beekeepers lost all their colonies, but losses overall were just above the norm. Mr Lovett said bees are under pressure from several sources – most notably the varroa mite, which is suspected of carrying a range of different viruses. These include the Aids-like Israeli Acute Paralysis Virus, believed to have wiped out huge numbers of bees.

In America up to 90 per cent of commercial bee colonies have been struck by CCD, or Mary Celeste Syndrome, over the past three years. Hundreds of colonies, up to 30,000 strong, began to die out with no explanation in 2005. One honey producer in Pennsylvania went from 1,000 colonies to fewer than eight in a matter of months.

CCD is so devastating that it has been compared with foot and mouth disease. It has spread in Europe to Spain, Portugal, Croatia, Greece, Germany and Poland, and also into South America. IAPV attacks the bees’ immune system and there is no cure, raising fears that it is only a matter of time before global crops are decimated, the scientists warned.

But Richard Ball, the Governent’s national bee inspector, denied the problems are as bad as claimed. He said: ”We do not think CCD is an issue in the UK yet.”

“Without bees, life as we know it will not exist.” Even if it is not as catastrophic as that quote implies, for those of us who rely on pollinators to produce next years new seedlings, this looks like it can have a bad effect. Maybe, we could all ensure with our general garden planting that there is a good supply of food available to the bee, through from early spring to late Autumn. This will improve the chances of survival for the unaffected hives.

In the meantime, the theories around what is the cause abound. Many people are putting it down to genetically modified crops, which abound in the USA. Others are attributing the cause to the widespread use of mobile phones.