Scientists at the University of York have identified plants that are helpful in maintaining healthy bee colonies. The study, published in the journal Frontiers in Sustainable Food Systems, will help select flowering plants to attract pollinators to gardens.
The team collected pollen samples from 57 plant species native to North America, including wild flowering plants and dried plants grown in the lab. The pollen was processed and analyzed for amino acid content, nonesterified fatty acids, protein to lipid ratio and omega-6 to omega-3 fatty acid ratio.
Without non-esterified fatty acids, bees live shorter lives, have weaker immune systems and are more vulnerable to environmental stressors. If insects consume them in the wrong ratio, they develop cognitive problems. Bees also need essential amino acids, which are important for cognitive health and reproduction, but an excess of amino acids increases susceptibility to certain parasites.
It turns out that plant species from the cabbage and bean families have the same level of essential amino acids compared to other plants from the same family. Daisies are particularly rich in essential amino acids. At the same time, plants with a high content of essential amino acids have a relatively low content of non-esterified fatty acids and vice versa.
Researchers also tested whether nearby plant species had the same nutritional value and whether species introduced to the area where they were collected were less nutritious than endemic species. It turns out that feeding on endemic plant species provides no nutritional benefits.
The authors conclude that most types of pollen contain essential nutrients, but to obtain the optimal amount of nutrients, bees will need to forage on several different types of plants.