The Pol-line breeding program was used by the USDA to move VSH traits from the lab into bees that commercial beekeepers would want to use. They have been very successful with the program's results.
We're now running a similar selection model, working with two of the three original Pol-line project commercial operations. As positive results from the USDA Pol-line program's performance become available, many will be curious as to the origin of the program and what was involved.
Bob Danka, USDA Bee Lab, Baton Rouge Research Leader writes: "Thanks for your interest in this effort. I am not sure how much detail you want but here is the basic story, which has three chapters.
"The bees were derived initially as an offshoot of the research described in an article that I will ask Adam to post. We tested outcrosses of VSH bees in a large, commercial, migratory beekeeping operation that does much crop pollination. We put 60-86 colonies in the field for two consecutive years, and were able to select the best colonies that survived after the bees had been through the coast-to-coast pollination circuit. The initial Pol-line population came from 18 total colonies harvested in 2009 and 2010. These bees were selected because they survived one year with original queens, they had low Varroa infestations, and they had large populations of adult bees."
"We subsequently ran another round of parallel tests in an operation that wintered in the Central Valley of California, pollinated almonds, and later made honey in Montana. We were able to pull in six outcrossed VSH colonies from one (2010) of the two years of the test. All these bees (24 colonies) from the first three years of tests were mixed as they were propagated annually beginning in 2010."
"In 2011 we began to test the Pol-line population, as outcrosses, against VSH outcrosses on a much larger scale in three large commercial operations. We ran a test that began with 560 colonies last spring (2012), and now are propagating 27 colonies selected from the outcrosses of Pol-line and VSH. These will be combined with what remains of the earlier breeding group. We currently also are establishing another group of colonies for testing and selection so we can further widen the genetic base, in case the Pol-line population continues to perform well and further propagation and distribution is desired."
"In sum, we have selected colonies from the best survivors of colonies that were used for intense migratory beekeeping (almonds, apples, lowbush blueberries and cranberries) and later also for honey production (Montana, North Dakota and South Dakota). It is a work in progress as we continue testing the potential of the bees while also harvesting new selected bees. We welcome objective feedback about what you are seeing." (Originally posted on vshbreeders.org, 2013)
The beauty of the "Pol-line" type breeding program is that it may be utilized within any significant population of honey bees, selecting for varroa mite resistance and any other desirable traits. USDA Bee Breeding Lab research results pave the way for attainable honey bee stock improvment.