The Buzz Newsletter

June 2010

 

 

Page 10

Beekeepers must focus on Varroa mites to beat CCD

By Dick Lehnert, Assistant Editor
Vegetable Growers Network
www.vegetablegrowersnews.com

Some vegetable growers are very dependent on beekeepers for the pollination of their crops, so they have been concerned about the current scourge of the bee world, Colony Collapse Disorder, which struck bees in 2006 and has caused devastating losses since.

Well, you can pass on this piece of advice to your beekeeper: Be vigilant, and do everything you can to control Varroa mites.

May Berenbaum, professor and head of the Department of Entomology at the University of Illinois, offered that management tip. She and a team of researchers there published a paper recently offering a complicated explanation of the cause of CCD. And while Varroa mites can’t be said to be the cause, they are a key part of the equation.

The researchers found that bees that were susceptible to CCD contained fragmented ribosomes, so they were less able to manufacture protein. Bees need to make protein for food, for disease resistance and to resist stresses caused by travel and insecticides in the environment.

The team of scientists offered an explanation for why the ribosomes were fragmented: The bees with CCD were infected by more viruses than were found in healthy bees. These are picorna-like viruses that “hijack” the ribosome, taking over the cellular machinery. The data suggest that the more viruses bees carry, the more susceptible they are to CCD.

And that’s where mites come in. Varroa mites carry viruses that infect the bees.

The fact that bees travel around a lot, moving to pollinate crops from Florida to California to upper Midwest, likely exposes them ot more viruses, Berenbaum said. Finally, what may happen is that the last virus becomes “the straw that breaks the camel’s back,” overcoming the bee’s capacity to repair ribosome damage, she said.

The team’s work didn’t get quite as much publicity as might have been expected for a significant advance in understanding CCD. That’s probably because the team did not find a simple explanation. There is apparently no single cause of CCD. Varroa mites aren’t the cause either, but they are a critical link in the chain.

She also thinks the discovery of the overabundance of ribosome fragments could lead to development of a simple molecular diagnostic tool that would allow beekeepers to detect CCD in its early stages. They would get an idea which hives are most susceptible. One member of her team, Jay Evans of the USDA Bee Laboratory in Beltsville, Md., is working on developing a diagnostic tool.

Berenbaum agreed that suppressing Varroa mites isn’t easy, given that they are increasingly resistant to the two major insecticides beekeepers can use. Still knowing that Varroa mites are a key place to focus might help.

Beekeepers should be pleased to know that other things are not causes. There had been concerns that CCD might be caused by a virus, especially a new one called Israeli acute paralysis virus. But she considers it no longer the “primary cause”; it is just one of several picorna-like viruses.

There have been concerns that insecticides might be the primary cause. But they, too, are merely one ona list of stressors and are not the primary cause. Nor are cell phone towers, a “cause” that made the news about the same time of her team’s discovery.

There work was reported in a paper published in the Proceedings of the National Academy of Sciences. Reed Johnson, University of Illinois, is the lead author. Gene Robinson, entomologist and neuroscience professor, is co-principal investigator, along with Berenbaum.  VGN

HONEY COOKIES

Printed from COOKS.COM

1 cup butter or non-hydrogenated vegetable shortening
1 cup honey (or to taste)
1 tsp. baking soda
1/2 tsp. ea. cinnamon, cloves, allspice
3 3/4 cups white whole wheat flour

In a saucepan, cook honey and butter together until it reaches the boiling point. Remove from heat and set aside to cool.

Whisk or sift together flour, baking soda and spices until no streaks remain. Add sufficient flour to the honey and butter mixture to make a soft dough (about 3 3/4 cups).

If dough seems too sticky, add a tablespoon of flour at a time. If dough seems too dry or dense, add a tablespoon of milk until dough is of a good consistency.

Form the dough into thin rolls, wrap in wax or parchment paper and chill thoroughly in refrigerator for at least 2 hours.

Slice into 1/8-inch thick slices and bake in a preheated 375°F oven for about 10 minutes or until done.

Variation: Add raisins, Craisins, chopped dates, or nuts (about 1 cup) if desired. Vanilla or finely grated citrus peels may be added for extra flavor.