Difference between revisions of "Team:Wageningen UR/Description"

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<p> What causes the loss of bee colonies? According to beekeepers we have spoken to and as has been suggested in scientific studies<sup><a href="#fn3" id="ref3">3,</a><a href="#fn4" id="ref4">4,</a><a href="#fn5" id="ref5">5</a></sup>, the most important factor is the mite <i>Varroa destructor</i>. <i>Varroa</i> mites feed on haemolymph (‘bee-blood’) weakening the bees, while spreading serious diseases like the deformed wing virus. Beekeepers and bee researchers stress that the first and most important step to save the bees should be to control <i>Varroa</i> more effectively. </p>
 
<p> What causes the loss of bee colonies? According to beekeepers we have spoken to and as has been suggested in scientific studies<sup><a href="#fn3" id="ref3">3,</a><a href="#fn4" id="ref4">4,</a><a href="#fn5" id="ref5">5</a></sup>, the most important factor is the mite <i>Varroa destructor</i>. <i>Varroa</i> mites feed on haemolymph (‘bee-blood’) weakening the bees, while spreading serious diseases like the deformed wing virus. Beekeepers and bee researchers stress that the first and most important step to save the bees should be to control <i>Varroa</i> more effectively. </p>
  
<p> Currently in the Netherlands and other European countries, beehives are treated against <i>Varroa</i> with a combination of organic products consisting of thymol, formic acid and oxalic acid. These compounds can contaminate beeswax and honey<sup><a href="#fn6" id="ref6">6</a></sup>. More importantly, beekeepers are wary that such compounds can be harmful to bees and humans when the concentration used is too high<sup>7,8</sup>. On the other hand, too low concentrations fail to kill <i>Varroa</i> and facilitate resistance<sup>9</sup>. The hobbyist character of beekeepers further adds to the concerns that accompany <i>Varroa</i> treatment. Beekeepers often care for their bees in their spare time and might not have time, resources or the experience to use existing treatments in the intended manner.  </p> </section>
+
<p> Currently in the Netherlands and other European countries, beehives are treated against <i>Varroa</i> with a combination of organic products consisting of thymol, formic acid and oxalic acid. These compounds can contaminate beeswax and honey<sup><a href="#fn6" id="ref6">6</a></sup>. More importantly, beekeepers are wary that such compounds can be harmful to bees and humans when the concentration used is too high<sup><a href="#fn7" id="ref7">7,</a><a href="#fn8" id="ref8">8</a></sup>. On the other hand, too low concentrations fail to kill <i>Varroa</i> and facilitate resistance<a href="#fn9" id="ref9">9</a></sup>. The hobbyist character of beekeepers further adds to the concerns that accompany <i>Varroa</i> treatment. Beekeepers often care for their bees in their spare time and might not have time, resources or the experience to use existing treatments in the intended manner.  </p> </section>
  
 
<section id="Bee T">
 
<section id="Bee T">

Revision as of 11:30, 4 October 2016

Wageningen UR iGEM 2016

 

 


Introduction

Honeybees are incredibly important pollinators responsible for the abundance and diversity of our food. Unfortunately, honeybees are in trouble: the fittingly named Varroa destructor (from here on ‘Varroa’ or ‘Varroa mite’)weakens the bees and spreads diseases. iGEM Wageningen UR 2016 aims to save the bees from Varroa.

Honeybees can pollinate an enormous range of plants through active collection of pollen1, making them important for pollination of crops. Apples, almonds and numerous other crops rely heavily on bee pollination, tying the diversity of our diet to the well-being of these insects1. Therefore, it is of key importance to keep bees alive and healthy.

Unfortunately bees are not doing well at all. There has been a sustained loss of bee colonies in the western world for at least 10 years. In 2014-2015, US beekeepers lost over 40% of their colonies2! Such numbers are unacceptable!

Varroa destructor

What causes the loss of bee colonies? According to beekeepers we have spoken to and as has been suggested in scientific studies3,4,5, the most important factor is the mite Varroa destructor. Varroa mites feed on haemolymph (‘bee-blood’) weakening the bees, while spreading serious diseases like the deformed wing virus. Beekeepers and bee researchers stress that the first and most important step to save the bees should be to control Varroa more effectively.

Currently in the Netherlands and other European countries, beehives are treated against Varroa with a combination of organic products consisting of thymol, formic acid and oxalic acid. These compounds can contaminate beeswax and honey6. More importantly, beekeepers are wary that such compounds can be harmful to bees and humans when the concentration used is too high7,8. On the other hand, too low concentrations fail to kill Varroa and facilitate resistance9. The hobbyist character of beekeepers further adds to the concerns that accompany Varroa treatment. Beekeepers often care for their bees in their spare time and might not have time, resources or the experience to use existing treatments in the intended manner.

Bee T

We propose a Varroa specific treatment through the use of engineered bacteria that releases toxin in a specified and regulated manner. The released toxin is not harmful to bees or humans. To do so, the bacteria will employ a network of regulation mechanisms to produce the toxin only when mites are present and when enough bacteria are present to effectively kill the mite. Other mechanisms are intended to strictly confine the bacteria to the treated hive, preventing them from spreading and mixing with natural ecosystems.

References

    1. The Plight of the Bees. Marla Spivak, Eric Mader, Mace Vaughan, Ned H Euliss Jr.. Environmental Science and Technology. Volume 45 Issue 1. pp 34–38. 2011

    2. A national survey of managed honey bee 2014–2015 annual colony losses in the USA. Nicola Seitz, Kirsten S Traynor, Nathalie Steinhauer, Karen Rennich, Michael E Wilson, James D Ellis, Robyn Rose, David R Tarpy, Ramesh R Sagili, Dewey M Caron, Keith S Delaplane, Juliana Rangel, Kathleen Lee, Kathy Baylis, James T Wilkes, John A. Skinner, Jeffery S. Pettis, Dennis vanEngelsdorp. Journal of Apicultural Research. Volume 54. Issue 4. May 2015

    3. An Observational Study of Honey Bee Colony Winter Losses and Their Association with Varroa destructor, Neonicotinoids and Other Risk Factors. Romée van der Zee , Alison Gray, Lennard Pisa, Theo de Rijk. Plos One. July 2015

    4. The German bee monitoring project: a long term study to understand periodically high winter losses of honey bee colonies. Elke Genersch, Werner von der Ohe, Hannes Kaatz, Annette Schroeder, Christoph Otten, Ralph Büchler, Stefan Berg, Wolfgang Ritter, Werner Mühlen, Sebastian Gisder, Marina Meixner, Gerhard Liebig, Peter Rosenkranz. Apidologie. Volume 41. Issue 3. pp 332–352. May 2010

    5. Varroa destructor is the main culprit for the death and reduced populations of overwintered honey bee (Apis mellifera) colonies in Ontario, Canada. Ernesto Guzmán-Novoa, Leslie Eccles, Yireli Calvete, Janine Mcgowan, Paul G. Kelly and Adriana Correa-Benítez. Apidologie. Volume 41. pp 443–450. 2010

    6. Residues of essential oils in honey after treatments to control Varroa destructor.J Serra Bonvehí, F Ventura Coll, J A Ruiz Martínez. Journal of Essential Oil Research. Volume 21. Issue 1. pp 22 - 28. March 2014

    7. Monoterpenoid-based preparations in beehives affect learning, memory, and gene expression in the bee brain. Elsa Bonnafé, Julie Alayrangues, Lucie Hotier, Isabelle Massou, Allan Renom, Guillaume Souesme, Pierre Marty, Marion Allaoua, Michel Treilhou, Catherine Armengaud. Environmental Toxicity. July 2016

    8. Lethal and sub-lethal effects of thymol on honeybee (Apis mellifera) larvae reared in vitro. Gael Charpentier, Cyril Vidau, Jean-Baptiste Ferdy, Jeremy Tabart, Angelique Vetillard. Plant Management Science. Volume 70. Issue 1. Pp 140 - 147. June 2013

    9. Control of Varroa: a guidelines for New Zealand Beekeepers. Mark Goodwin, Cliff Van Eaton. New Zealand Ministry of Agriculture and Forestry. 2001