Location: Southern Horticultural Research Unit
Project Number: 6062-21430-004-039-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2024
End Date: Dec 31, 2026
Objective:
Bees are essential pollinators, significantly contributing to the reproduction of a diverse array of wild plants and the productivity of cultivated crops, thus supporting biodiversity and agricultural yields. In response to the decline of bee populations and the associated risks to global food security, various strategies have been proposed to reduce disease spread and various environmental stress among pollinators. These include the implementation of new regulations and pest control approaches, such as Integrated Pest and Pollinator Management and establishing pollinator habitats by planting native flowering plants. However, the enforcement of these strategies is often inadequate in many regions, necessitating additional measures to mitigate the negative impacts of environmental stressors including pathogen exposure. Recent research has explored innovative strategies, including the use of probiotics and micronutrient-enhanced foods. Probiotics are known for their positive effects on various animals as well as human health, helping to combat infections and manage non-communicable diseases. Micronutrients are similarly vital for maintaining health, with deficiencies leading to various illnesses that can be alleviated through supplementation. In the context of insects, the supplementation of probiotics has been shown to improve the performance and yield of mass-reared insects used for food and feed. Additionally, studies have indicated that micronutrients can enhance the efficiency of macronutrient use in grassland arthropods, including insects. Research specifically focused on pollinators has demonstrated that probiotics and micronutrients can aid in detoxifying pesticides and boosting immunity against pathogens, among other benefits. This project aims to determine the roles of probiotics and micronutrients in protecting managed species of two solitary bees and a bumble bee from pathogens and other environmental stressors, such as exposure to extreme temperatures and xenobiotics.
The main objectives of this project is to determine potential probiotic and micronutrient supplementation candidates for bees, and to determine the effects of important probiotic and micronutrient supplementation on Osmia and bumble bee health.
Approach:
We will conduct two sets of bioassays determining the impact of dietary probiotic and micronutrient supplements on two Osmia and a bumble bee species. In the first set, we will conduct bioassays with probiotic supplements. Our candidate probiotic supplements are commercials strains of Bacillus subtilis and Lactobacillus plantarum. B. subtilis – long established as a safe bacterial strain for human consumption, as a vessel for molecular production or as probiotic food supplement has been shown to degrade xeneobiotics such as pyrethroids and the organophosphates which could potentially contribute to detoxification and overall health of bees as a gut symbiont. The other species L. plantarum, also exhibiting organophosphate-degrading capabilities have been shown to benefit the health and recovery of antibiotic-treated wintering honey bees at appropriate doses along with B-vitamins, one of our micronutrient supplement candidates – which could also have similar beneficial effects on non-Apis bees. In laboratory bioassays, we will develop different dose regimes of these probiotic strains and will evaluate their impact on two solitary bee species (Osmia species) and a commercially available bumblebee species. Bee species will be exposed to major environmental stressors that bees are frequently exposed to field environment in the Midwestern region and the impact will be measured using various end points, such as longevity, brood development, gut microbiome.
In another set of laboratory bioassays with Osmia and bumble bees, we will determine the impact of supplementation of micronutrient Zinc which is known to provide survival and immune benefits to honey bees. We will also examine plant sterols, or phytosterols, as in previous studies they have been shown to contribute to the survival, development and reproduction of not only honey bees but also bumble bees and stingless bees, highly indicative that they will also benefit solitary bees. The supplements will be tested individually first. The most promising candidates will then be combined, most notably a probiotic strain with a micronutrient, for further investigation for any synergistic or antagonistic effects.
