Pollination: Seeking Solutions

Keith Delaplane

Tented plants

Related Information
>	Carl Hayden Bee Research Center
>	"Honey Bees Mite Breathes Easier," Agricultural Research magazine
>	"Scientists Comb Hives for Mite-Resistant Honey Bees," USDA news
>	"Screening Mites From Honey Bees," USDA news
>	USDA Bee Biology and Systemics Lab, Utah
>	USDA Bee Research Lab, Maryland
>	USDA Honey Bee Breeding genetics and Physiology Lab, Louisiana
>	"Varroa-Tolerant Bees Keep Hives Buzzing," Agricultural Research magazine

Seeking Solutions

The Mission

Keith Delaplane is an Extension Service entomologist with the University of Georgia College of Agricultural and Environmental Sciences.

"Our pollinators are a vulnerable resource that merits conservation. The stability of traditional honey beekeeping is jeopardized by two exotic parasitic mites that entered the United States in the 1980s — the honey bee mite (Acarapis woodi) and varroa mite (Varroa sp.).

"Mites usually kill colonies unless they are controlled with good management and synthetic acaricides. Feral honey bee colonies rarely live more than one season, and managed colonies require expensive and intense care. As a result, the number of beekeepers has declined.

"My extension and research goals are to (1) improve profitability and sustainability of traditional honey beekeeping by developing integrated strategies to control parasitic mites and (2) develop management recommendations for increasing efficiency of bee pollinators of crops. The overall goal is a large and sustainable bee population for pollination, honey production, and recreation."

Blueberry Pollination

A 1995-97 honey bee program survey showed that honey bees are the most abundant pollinator of blueberries and carry the highest percentage of blueberry pollen on their bodies.

A recent study of blueberry bushes showed that thorough pollination increased yields dramatically.

Bushes were observed in three environments: covered with a tent containing no bees, in the open field and covered with a tent containing 6,400 bees.

Fruitset in plants tented with bees was twice that of the open plants. Open plants and those tented with no bees showed little difference in fruitset.

Fruitset in Blueberries

		80%



	39%
31%



Tented without bees	Open	Tented with bees

Eliminating Pests

Delaplane is doing his part to fight these parasitic mites and other bee pests. "My research focuses on alternative controls that are less chemically intense," he says.

He has tested a hive screen that controls the varroa mites. "The screen creates a false floor in the bee hive," he says. "When the mites fall through the screen, they have trouble climbing back onto the bees."

In 1992 the UGA honey bee program developed a safe and environmentally friendly way to treat tracheal mites — a patty of vegetable shortening and sugar. As bees eat the sugar in the patty, they get oil on their bodies, which protects them from the parasites.

A 1995 UGA study showed that antibiotics can help bees overcome some of the mites' negative effects.

Teaming with Clemson University from 1995-98, the honey bee program developed the country's first economic threshold for varroa mites. This indicates the level of infestation at which a beekeeper should treat a hive. Such thresholds help eliminate unnecessary chemical treatments.