Bumblebees Cannot Taste Pesticides in Nectar Even at Lethal Concentrations

According to a new study, bees have no clues when they consume contaminated nectar because they can't determine the presence of pesticides.

Bumblebees Can't Taste Pesticides

Researchers from the University of Oxford have learned that bees can't detect pesticides. The new study suggests that the insects cannot avoid contaminated nectar, putting them at risk of pesticide exposure and threatening crop pollination.

To find out if bumblebees (Bombus terrestris) would avoid drinking pesticides over a wide range of concentrations and if they could taste neonicotinoid and sulfoximine pesticides in nectar that resembled oilseed rape (Brassica napus), the researchers employed two ways. Initially, they recorded the reactions of neurons in taste sensilla, or "tastebuds," on the bumblebee's mouthparts using electrophysiology. This made it possible for scientists to monitor the frequency of neuronal "fires" and, consequently, the intensity of the taste reaction.

The feeding habits of the bumblebees were also examined by the researchers, who provided them with sugar solutions laced with pesticides or pure sugar solutions.

The findings showed that the neurons' reactions were the same whether the bees sipped sugar solution or insecticides containing sugar. This suggests that the mouthparts of bumblebees cannot recognize and steer clear of common pesticides found in nectar.

Whether or not pesticides were present in the solution, the bees ate the same quantity of food in the behavior trials. This was true even when pesticide concentrations were high enough to cause serious bee illness.

The results are significant because they demonstrate that bumblebees' ability to use their sense of taste to avoid pesticide exposure is compromised.

Since bees are at risk of consuming chemicals and won't refrain from doing so, the research is crucial regarding pesticide usage on outdoor crops. These results may be utilized to locate a non-toxic substance that repels bees and can be sprayed on pesticide-treated crops that don't need pollination, said Dr Rachel Parkinson, Department of Biology, University of Oxford, lead author of the study.

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How Important Are Bees?

Bees are very important in the ecosystem because they pollinate the plants. They carry pollen between plants of different sexes to fertilize them and help them reproduce. These insects also help plants thrive by preventing inbreeding.

Aside from being the greatest pollinators, they offer premium foods like honey, royal jelly, pollen, propolis, beeswax, and honey bee venom.

A significant source of income for many rural lives also comes from beekeeping. The western honey bee is the world's most widely used managed pollinator, with over 80 million hives producing an estimated 1.6 million tonnes of honey a year, according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).

The UN has declared 20 May World Bee Day to increase public understanding of the vital role that pollinators like bees play in preserving human and environmental health. The date falls on the birthday of Anton Janša, a Slovenian who invented modern beekeeping methods in the eighteenth century and admired bees for their remarkable productivity with minimal care.