Honey Bees May Survive Pesticides with a Better Diet of Natural Pollen

When it comes to honey bees, diet is all important. It turns out that honey bees fed on a natural diet of pollen are far more resistant to pesticides than those that are fed an artificial diet. The findings could give beekeepers another tool when it comes to saving bee populations.

"Honey bees are exposed to hundreds of pesticides, while they are foraging on flowers and also when beekeepers apply chemicals to control bee pests," said Christina Grozinger, one of the researchers, in a news release. "Our study demonstrates that exposure to non-lethal doses of at least two of these pesticides causes large changes in the expression of genes involved in detoxification, immunity and nutrition-sensing. This is consistent with results from previous studies that have found that pesticide exposure compromises bees' immune systems. Furthermore, our study reveals a strong link, at the molecular level, between nutrition, diet and pesticide exposure."

In order to explore what might bolster bees a bit more against pesticides, the researchers examined bee diet. The scientists first fed one of two miticides-coumaphos or fluvalinate-to bees for a period of seven days. Then they extracted RNA from the bees and attached a fluorescent marker to the RNA and examined differences in gene expression patterns. They found changes in 1,118 pieces of RNA related to detoxification, immunity and nutrition.

Then, the researchers examined the susceptibility of bees to pesticide stress after consuming a pollen diet or an artificial diet. In the end, they found that the bees fed a pollen-based diet had reduced sensitivity to pesticides when compared to the bees that were fed an artificial diet.

"This if the first time such a strong link between pesticide exposure and diet has been demonstrated at the molecular level, and the first time the effects of artificial versus natural diets have been explored in terms of resistance to pesticides," said Grozinger. "Diet and nutrition can greatly impact the ability of bees to resist pesticides, and likely other stressors."

The findings are published in the Journal of Insect Physiology.