Bumblebees make flowers grow bigger and smell sweeter

When bees pollinate flowers they grow bigger and smell better, scientists have found

Sarah Knapton, science editor
14 MARCH 2017 • 4:00PM Article originally published here

Gardeners have long known the importance of bumblebees and honeybees for pollination, but the insects can also help flowers grow bigger and smell more fragrant, scientists have discovered.

Swiss researchers found that plants evolve differently depending on the insect which is pollinating them.

Tests on a type of cabbage species called field mustard, a close relative of oilseed rape, showed that when pollinated by bumblebees, the plants grew three inches taller than with hover flies in just nine generations.

They also flowered a day earlier and had double the fragrance. And when placed on ultraviolet light, they had more colours which bees can see.

“The traditional assumption is that evolution is a slow process,” said Professor Florian Schiestl.

“But a change in the composition of pollinator insects in natural habitats can trigger a rapid evolutionary transformation in plants.”

The field mustard plants grew three inches (eight cms) taller when pollinated by bees


The change happens because insects differ in their preference for plants. Bees like taller more fragrant plants so will seek out and pollinate those more often than shorter, unfragranced varieties, causing the bigger, smellier plants to thrive.

Flies, alternatively are not so effective at pollination, and so plants will self-pollinate more often, which slows down the emergence of new traits.

The bee pollinated plants (shown on the left) had double the fragrance


Professor Schiestl said the rapid decline of bee populations in Britain could be leading to flowers that do not grow as abundantly or smell as fragrant. In the long term it could also reduce the genetic diversity of plants leaving them more susceptible to disease.

Friends of the Earth (FOE) are currently encouraging gardeners to plant bee-friendly gardens ahead of the Great British Bee count in May and June.

Purple and blue flowering plants are best because they are easier for the bees to see, and different species prefer different shapes of flower, so a mix of snapdragons, lavender, heathers, sunflowers, wallflowers, yarrow and verbena will attract all kinds. They are also drawn to shrubs, trees, fruit and vegetables as well as spring and autumn flowering bulbs.

Bees like purple and blue flowers because they find them easier to see


“Bees are brilliant pollinators – and this study underlines their importance,” said Friends of the Earth bee campaigner Paul de Zylva.

“Bees aren’t the only pollinator, but many plants will not thrive if they are only visited by other insects, as this new research shows.

“But Britain’s bees are under threat, and we can all do more to help them – such as by growing pollinator-friendly plants, avoiding pesticides and turning gardens and other spaces into bee-friendly habitats.

“And you can check out the bees in your garden, park or neighbourhood by taking part in the Great British Bee Count later this spring.”

Gardeners with lawns are also encouraged to leave dandelions and clover to flower for the bees, and a ‘messy corner’ of old wood and leaves will provide shelter. Chemical pesticides should also be avoided, especially those containing bee-harming neonicotinoid pesticides.

Bee expert Professor Simon Potts from the University of Reading said: “Everyone can help our under-threat bees this Spring. Research has already show that our towns and cities can be great places for bees – if the right plants are grown in parks and green spaces.

“With a bit of bee-friendly gardening, and a bit more tolerance of weeds, we can all help to make sure our streets and neighbourhoods are buzzing with these amazing insects.”

The research was published in Nature Communications and to sign up for the bee count visit www.greatbritishbeecount.co.uk.

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Saving honeybees in the US

honeybees on honeycomb

honeybees on honeycomb

With a workforce of billions, they contribute more than $15bn (£9bn) to the US economy each year – but as populations decline, can the humble honeybee be saved?

A giant inflatable corn on the cob towers over the hundreds of stalls at the Wisconsin State Fair. Food is the main draw, in what’s a showcase for local produce. The unhealthier, it seems, the better.

Families can be seen piling in mouthfuls of everything from sausages dripping in fat, to cheese curds, and sticky cherry pie. Some of the more unusual delicacies include deep-fried cookies and fish and chips on a stick.

Standing on the stage under the tent at the Wisconsin Food Pavilion are two immaculately dressed young women wearing crowns on their heads and sporting silk sashes, the kind usually seen at beauty pageants.

Anna Kettlewell (right) and Lois Hoftiezer Graf (second from right) join two other former Wisconsin Honey Queens in promoting the honey industry

Anna Kettlewell (right) and Lois Hoftiezer Graf (second from right) join two other former Wisconsin Honey Queens in promoting the honey industry

They are former Wisconsin “Honey Queens” – statewide ambassadors for the beekeeping and honey industry. Their job is to travel throughout the state, speaking about honeybees at schools, festivals and farmers’ markets.

Anna Kettlewell held the title in 1998. She is on stage showing off the benefits of the sticky stuff in a cooking demonstration, as she makes an ice-cream syrup.

But she is also here to educate people about the wider importance of the honeybee, which is the official state insect of Wisconsin.

Wisconsin honey producers association

Wisconsin honey producers association

“Honeybees are absolutely vital for the nation’s food supply. One third of our diet is dependent on the honeybee,” she says, reciting her Honey Queen talking points.

“The beekeeping industry in Wisconsin is very important for our cranberry industry. Honeybees are responsible for pollinating our cranberry crops in the state, which is our state fruit.”

Another Wisconsin Honey Queen, 60-year-old Lois Hoftiezer Graf, is handing out samples of the different varieties of honey made in the state. She dishes out spoonfuls dressed in the immaculately preserved sash she was given when she took the title in 1972.

“I think the marketing has improved quite a lot,” says Lois of the changes in the honey industry since then. “The other thing that has changed in our culture, is we’re much more interested in natural and organic foods.”

The honeybee is important to both the Wisconsin and the US economies

The honeybee is important to both the Wisconsin and the US economies

But as tastes have changed, so too have the fortunes of the honeybee, which has seen its population decline across the United States.

In the past 60 years the number of honeybee colonies has fallen from six million beehives in 1947, to just 2.5 million today, according to the White House.

The honeybee’s decline

honeybee cleaning spilt honey from damaged honeycomb

honeybee cleaning spilt honey from damaged honeycomb

In October 2006, some beekeepers began reporting losses of 30-90% of their hives. While colony losses are not unexpected, especially over the winter, this magnitude of losses was unusually high

In 1995-96, Pennsylvania beekeepers lost 53% of their colonies without a specific identifiable cause

In 1903, in the Cache Valley in Utah, 2,000 colonies were lost to an unknown “disappearing disease” after a “hard winter and a cold spring”

Source: US Department of Agriculture

This decline, the White House says, could pose a real threat to US agriculture, because of the role the honeybee plays in the pollination of fruit, nuts and vegetables.

It might be a tiny little insect, but one mouthful in three, directly or indirectly, benefits from honeybee pollination, according to the US Department of Agriculture. Honeybees enable the production of at least 90 commercially grown crops in the US.

honeybees on honeycomb

honeybees on honeycomb

In a sign of how seriously this is being taken, in June, President Obama launched a taskforce to protect the honeybee. The White House is investing $50m into research and action to stem the decline, improve habitats and promote better education around the issue.

It is welcome news for Ryan Stern, a beekeeper who runs Concord Farms in Sullivan, Wisconsin. His business began as a few hives, and is now a large, commercial operation.

“I was growing in [terms of] numbers of bee hives and I was starting to not be able to manage those bee hives and work full-time correctly, and I had to make a choice of what I wanted to do.

“I really enjoy working with the bees every day, it’s nice being out in the sun working with them. Being stung is not the most enjoyable thing but every job has its downfalls.”

Ryan Stern's business began as just a few hives but has grown over the years

Ryan Stern’s business began as just a few hives but has grown over the years

Ryan pulls out a frame from one of his 48 hives, to reveal a swarm of bees, navigating the honeycomb furiously. As he scratches a small section of the frame, a large, sticky drop of honey falls from it.

This is Ryan’s livelihood, but harsh winters, and pesticides have made it tough for him to keep all his bees alive.

“If you can keep your bees alive you can make money, but keeping bees alive definitely costs a lot of money by itself.

“Between the pests, the disease, nutrition, lack of forage, it’s definitely just a hard environment to keep them alive in, and unfortunately with genetically modified plants some of the pollens and stuff off of these crops you don’t really want to get into your bee hives.”

Some years Ryan says he measures success by how healthy his bees are, not by what is produced.

Ryan Stern says keeping bees alive is a costly business

Ryan Stern says keeping bees alive is a costly business

The White House has named Wisconsin as one of five states where farmers and ranchers will be given extra funding to continue their work in establishing new habitats for honeybee populations, but Ryan is not yet sure if his farm will reap the benefits of that.

Still, he thinks President Obama’s action on the bee industry is a good move, and he says everyone, even those who aren’t in agriculture, needs to focus more on the role the honeybee plays.

“You don’t have to have 100 acres to help with the issue. Every lawn, every yard can help. It’s important because it will affect the food supply everywhere.

“If there’s a shortage in one area, it’s a global economy, so it’s going to change food prices all across the world.”

Article originally published here

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