Colony-Level Effects of Amygdalin on Honeybees and Their Microbes
Amygdalin, a cyanogenic glycoside, is found in the nectar and pollen of almond trees, as well as in a variety of other crops, such as cherries, nectarines, apples and others. It is inevitable that western honeybees (<i>Apis mellifera</i>) consistently consume amygdalin during almond poll...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-11-01
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| Series: | Insects |
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| Online Access: | https://www.mdpi.com/2075-4450/11/11/783 |
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| author | James P. Tauber Cansu Ö. Tozkar Ryan S. Schwarz Dawn Lopez Rebecca E. Irwin Lynn S. Adler Jay D. Evans |
| author_facet | James P. Tauber Cansu Ö. Tozkar Ryan S. Schwarz Dawn Lopez Rebecca E. Irwin Lynn S. Adler Jay D. Evans |
| author_sort | James P. Tauber |
| collection | DOAJ |
| description | Amygdalin, a cyanogenic glycoside, is found in the nectar and pollen of almond trees, as well as in a variety of other crops, such as cherries, nectarines, apples and others. It is inevitable that western honeybees (<i>Apis mellifera</i>) consistently consume amygdalin during almond pollination season because almond crops are almost exclusively pollinated by honeybees. This study tests the effects of a field-relevant concentration of amygdalin on honeybee microbes and the activities of key honeybee genes. We executed a two-month field trial providing sucrose solutions with or without amygdalin <i>ad libitum</i> to free-flying honeybee colonies. We collected adult worker bees at four time points and used RNA sequencing technology and our HoloBee database to assess global changes in microbes and honeybee transcripts. Our hypothesis was that amygdalin will negatively affect bee microbes and possibly immune gene regulation. Using a log<sub>2</sub> fold-change cutoff at two and intraday comparisons, we show no large change of bacterial counts, fungal counts or key bee immune gene transcripts, due to amygdalin treatment in relation to the control. However, relatively large titer decreases in the amygdalin treatment relative to the control were found for several viruses. Chronic bee paralysis virus levels had a sharp decrease (−14.4) with titers then remaining less than the control, Black queen cell virus titers were lower at three time points (<−2) and Deformed wing virus titers were lower at two time points (<−6) in amygdalin-fed compared to sucrose-fed colonies. Titers of <i>Lotmaria passim</i> were lower in the treatment group at three of the four dates (<−4). In contrast, Sacbrood virus had two dates with relative increases in its titers (>2). Overall, viral titers appeared to fluctuate more so than bacteria, as observed by highly inconstant patterns between treatment and control and throughout the season. Our results suggest that amygdalin consumption may reduce several honeybee viruses without affecting other microbes or colony-level expression of immune genes. |
| first_indexed | 2024-03-10T14:56:00Z |
| format | Article |
| id | doaj.art-9063a3f84ce94269816b06d24aaea09e |
| institution | Directory Open Access Journal |
| issn | 2075-4450 |
| language | English |
| last_indexed | 2024-03-10T14:56:00Z |
| publishDate | 2020-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Insects |
| spelling | doaj.art-9063a3f84ce94269816b06d24aaea09e2023-11-20T20:34:24ZengMDPI AGInsects2075-44502020-11-01111178310.3390/insects11110783Colony-Level Effects of Amygdalin on Honeybees and Their MicrobesJames P. Tauber0Cansu Ö. Tozkar1Ryan S. Schwarz2Dawn Lopez3Rebecca E. Irwin4Lynn S. Adler5Jay D. Evans6Bee Research Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Beltsville, MD 20705, USABee Research Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Beltsville, MD 20705, USABee Research Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Beltsville, MD 20705, USABee Research Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Beltsville, MD 20705, USADepartment of Applied Ecology, North Carolina State University, Raleigh, NC 27695, USADepartment of Biology, University of Massachusetts, Amherst, MA 01003, USABee Research Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Beltsville, MD 20705, USAAmygdalin, a cyanogenic glycoside, is found in the nectar and pollen of almond trees, as well as in a variety of other crops, such as cherries, nectarines, apples and others. It is inevitable that western honeybees (<i>Apis mellifera</i>) consistently consume amygdalin during almond pollination season because almond crops are almost exclusively pollinated by honeybees. This study tests the effects of a field-relevant concentration of amygdalin on honeybee microbes and the activities of key honeybee genes. We executed a two-month field trial providing sucrose solutions with or without amygdalin <i>ad libitum</i> to free-flying honeybee colonies. We collected adult worker bees at four time points and used RNA sequencing technology and our HoloBee database to assess global changes in microbes and honeybee transcripts. Our hypothesis was that amygdalin will negatively affect bee microbes and possibly immune gene regulation. Using a log<sub>2</sub> fold-change cutoff at two and intraday comparisons, we show no large change of bacterial counts, fungal counts or key bee immune gene transcripts, due to amygdalin treatment in relation to the control. However, relatively large titer decreases in the amygdalin treatment relative to the control were found for several viruses. Chronic bee paralysis virus levels had a sharp decrease (−14.4) with titers then remaining less than the control, Black queen cell virus titers were lower at three time points (<−2) and Deformed wing virus titers were lower at two time points (<−6) in amygdalin-fed compared to sucrose-fed colonies. Titers of <i>Lotmaria passim</i> were lower in the treatment group at three of the four dates (<−4). In contrast, Sacbrood virus had two dates with relative increases in its titers (>2). Overall, viral titers appeared to fluctuate more so than bacteria, as observed by highly inconstant patterns between treatment and control and throughout the season. Our results suggest that amygdalin consumption may reduce several honeybee viruses without affecting other microbes or colony-level expression of immune genes.https://www.mdpi.com/2075-4450/11/11/783honeybeesnatural productsamygdalinmicrobesviruses |
| spellingShingle | James P. Tauber Cansu Ö. Tozkar Ryan S. Schwarz Dawn Lopez Rebecca E. Irwin Lynn S. Adler Jay D. Evans Colony-Level Effects of Amygdalin on Honeybees and Their Microbes Insects honeybees natural products amygdalin microbes viruses |
| title | Colony-Level Effects of Amygdalin on Honeybees and Their Microbes |
| title_full | Colony-Level Effects of Amygdalin on Honeybees and Their Microbes |
| title_fullStr | Colony-Level Effects of Amygdalin on Honeybees and Their Microbes |
| title_full_unstemmed | Colony-Level Effects of Amygdalin on Honeybees and Their Microbes |
| title_short | Colony-Level Effects of Amygdalin on Honeybees and Their Microbes |
| title_sort | colony level effects of amygdalin on honeybees and their microbes |
| topic | honeybees natural products amygdalin microbes viruses |
| url | https://www.mdpi.com/2075-4450/11/11/783 |
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