Stingless bee species depend on a complex fungal community to survive

Image of stingless bee.

(FAPESP) A new study shows that the larvae of the Brazilian stingless bee Scaptotrigona depilis depend on interactions between three different species of fungus to complete their development and reach adulthood. “The new findings demonstrate that the interactions between these social insects and their microbiota are much more complex than we can imagine. This should serve as a warning against the indiscriminate use of pesticides in agriculture, since many are lethal to fungi.”

There’s a new group of workers spreading organic pesticide on crops: bees

Image of bee boxes next to field.

(Fast Company) Bees are great at retrieving tiny cargo: their main job is to visit flowering plants in order to gather pollen and nectar for their hive. Now Bee Vectoring Technologies just received EPA approval for an organic fungicide that bees can carry directly from hive to crop. The company has used this system in commercial-size test fields to reduce gray mold on strawberries while increasing yields by at least 10%, and eliminate gray mold and the more nefarious monilinia blight in blueberries. The company projects that it can reduce pesticide use by 50 to 75 percent at conventional farms that are willing to widely adopt the new practice.

Microbes on the menu for bee larvae

Image of bee brood in cells.

(Phys.org/USDA) Nature’s famously busy insect isn’t strictly vegan after all. A team of Agricultural Research Service and university scientists has shown that bee larvae have a taste for “microbial meat.” In fact, the team observed an appetite for microbial meat among brood that spanned 14 species distributed across all major families of social and solitary bees—Melittidae, Apidae and Megachilidae among them. The findings underscore the need to examine what effects fungicide use on flowering crops can have on the microbial make up of pollen fed to brood and, in turn, their development. The research on bee larvae consumption of “microbial meat” can be found here.

New Xerces fact sheet takes a deeper look at fungicides and their effects on pollinators

Graphic showing how fungicides can impact the health of pollinators.

(Xerces Society) Research has shown that some fungicides kill bees on contact. Studies have shown that some fungicides increase the toxic effects of certain insecticides. Fungicide exposure has also been linked to higher levels of parasitic and viral infections in honey bee colonies, suggesting that some fungicides may impair a bee’s ability to fight disease. The Xerces Society’s new fact sheet, “Protecting Pollinators from Pesticides: Fungicide Impacts on Pollinators”, reviews the current literature on fungicides and pollinators to help piece together potential risks and how best to respond.

A combination of agrochemicals shortens the life of bees, study shows

Close up of bee on flower.

(São Paulo Research Foundation) A new study by Brazilian biologists suggests that the effect of pesticides on bees could be worse than previously thought. Even when used at a level considered nonlethal, an insecticide curtailed the lives of bees by up to 50 percent. The researchers also found that a fungicide deemed safe for bees altered the behavior of workers and made them lethargic, potentially jeopardizing the survival of the entire colony.

Sivanto pesticide cocktail can harm honey bees

Image of honey bee on purple flower.

(University of California – San Diego) Recent research shows that worst-case, field-realistic doses of Sivanto, in combination with a common fungicide, can synergistically harm honey bee behavior and survival. “The idea that this pesticide is a silver bullet in the sense that it will kill all the bad things but preserve the good things is very alluring but deserves caution.”