Big Job Is a Good Fit for the Right Bee
By Marcia Wood
September 27, 1999
When the job is pollinating crops, it might pay to bring in the
specialists--especially those whose superior work habits offset the fact
they're outnumbered 10 to one.
An entomologist with the Agricultural
Research Service has found that the sunflower leafcutting bee often does a
better job pollinating sunflowers than the more common domesticated honey bee.
In outdoor enclosures, one of the two kinds of sunflowers used in
Tepedino's experiments produced larger and heavier seeds when pollinated by
sunflower leafcutting bees. According to Tepedino, the sunflower leafcutting
bees spread out evenly among the sunflowers rather than visiting just the
plants nearest their nesting boxes. Tepedino is based at the ARS
Bee Biology and Systematics
Laboratory in Logan, Utah.
The sunflower leafcutting bees, dark-brown to black insects about 3/4-inch
to 1-inch long, are native to southern Canada and most of the United States.
They are known to scientists as Megachile pugnata. The domesticated
honey bee--originally from Europe-- is Apis mellifera.
For the test, Tepedino used four 100-by-20-foot screened enclosures, owned
by Pioneer Hi-Bred International, Inc., at
Woodland, Calif. Each cage contained approximately 600 sunflower plants.
For about 2-1/2 weeks, about 100 sunflower bees in each of two cages
performed pollination chores. Meanwhile, a few thousand domestic honey
bees--about 10 times more than the sunflower leafcutting bees--performed the
same task in two other cages.
The test was the first using sunflower leafcutting bees to pollinate hybrid
sunflowers in field cages. Earlier work by other ARS researchers at Logan
scrutinized the bees in open fields. For details, see the story in the current
issue of the ARS magazine, Agricultural Research, and on the World Wide
ARS is USDA's chief research agency.
Scientific contact: Vincent J.
Tepedino, ARS Bee Biology and
Systematics Laboratory, 5310 Old Main Hill, Logan, UT 84322; phone (435)
797-2559, fax (435) 797-0461, firstname.lastname@example.org.