How sunflowers can save bumblebees from extinction

By Mark Waghorn via SWNS

The sunflower - inspiration of Vincent Van Gogh's most famous painting - could save bumblebees from extinction, according to new research.

Its pollen provides a natural medicine that protects the vital pollinators from disease, say scientists.

The spiny texture kills a gut bug called Crithidia bombi which is decimating numbers.

The common pathogen increases bee mortality under stressful conditions - reducing queens' success at establishing colonies by 40 percent.

It also leads to significant reductions in their mass, male production and overall fitness.

Lead author Dr. Laura Figueroa, of Massachusetts Amherst University, said: "Like humans, bees can tailor their diet to boost their gut and immune health."

Sunflowers can grow to astounding heights. The world record for the tallest stands at a staggering 30 feet.

There are over 70 different varieties including the Russian mammoth, the elf, the teddy bear and the moulin rouge.

Earlier studies have established their pollen can help bees resist some infections. But no one knew why.

Lead author Dr. Laura Figueroa, of Massachusetts Amherst University, said: "It could be because of the really spiny shape, it could be the unique chemistry - or it could be both."

To test what gave the pollen its anti-parasitic power, the US team first separated the pollen's outer shell from chemical metabolites in its core.

They then fed the shell-only pollen to one group of bees and gave the metabolite centres to the others. A third group received whole pollen.

Bees munching on the spiny shells or whole pollen had up to 94 percent less C. bombi in their gut than those eating only the chemical-packed pollen centers.

Bees that ate pollen exteriors had the same reduction in the harmful gut pathogen as those eating whole pollen, reports New Scientist.

Figueroa said: "The chemistry isn't the main driver – it's the physical structure. It was a really clear pattern."

Bees produce over a third of our food. They are being wiped out by climate change, pesticides and diseases - reducing our ability to grow crops.

Sunflowers have many uses. The seeds provide food for us and wild birds, under-threat British bees love the pollen and nectar - and sunflower oil is extracted for cooking and use in beauty products. Native Americans used certain types of sunflower medicinally for respiratory ailments.

Dr. Cedric Alaux, of the French National Institute for Agriculture, Food and Environment who was not involved in the work, said: "The study adds a new brick to the pollen and bee relationship by pointing out the physical effects."