Bee's ability to avoid toxic flowers

Apr 2, 2007 09:14 GMT  ·  By

They say a rose can be venomous...

Even if a beautiful woman can have a nasty character, there are indeed beautiful flowers that can be toxic.

And if the nectar from these flowers would reach the honey you enjoy every morning ...

It is still a puzzle for the researchers why many spring flowers displaying bright advertisements for sweet rewards to lure honeybees would try to poison them with poisonous nectars.

Even some common crop or garden plants like Rhododendrons and almond trees can have toxic nectar.

The honeybee accounts for the pollination of at least 1/3 of the world's crop plants and around this insect there is a many million business.

But are honeybees able to determine if a nectar harbors toxins or not, and does this affect their ability to pollinate plants?

The way toxins in nectar influences a honeybee's willingness to eat floral nectar has been investigated by a team led by Dr Geraldine Wright (Newcastle University).

Honeybees were found to be endowed with the ability of making a connection between almost any color, shape, texture or scent with food.

The new analysis on the honeybee genome has showed that honeybees have relatively few genes for taste receptors compared to other evolved insects of a similar size like those from the Diptera Order (which includes flies and mosquitoes).

That's why researchers have thought that perhaps honeybees had a decreased need to track down and learn about toxins, even if some floral nectar is toxic.

But the new research carried out by Wright's team points out that honeybees could have the ability to detect the toxins, even if they are not able to taste them.

The team discovered that both the carbohydrates level and the toxin presence in nectar influenced a honeybee's memory for learned odors.

Honeybees learned not to react to odors linked with toxins within 20 min of ingesting toxins, and this behavior will be kept up to 24 hours after the first contact with a toxin.

Thus, honeybees must first take a dose of unpleasant taste before learning how to avoid bad flowers.