mr clemens writes:
There seems to be a great deal of attention given to AHB and possible AHB infiltration.AHB infiltration I decided to try Italian Cordovan bees. This way, if a colony has a queen of Cordovan coloration, I know she is pure Italian Cordovan. If all or most of her workers also exhibit Cordovan coloration, I know she was mated with drones also carrying the Cordovan gene (no chance of them being AHB, yet). If a queen showing herself to be pure Italian Cordovan produces workers without Cordovan coloration I know she was mated with non-Cordovan drones and her workers might possibly be 1/2 AHB. And if a hive which had a Cordovan colored queen, now has a queen without Cordovan appearance, she may be AHB. If 1/2 of her drones are Cordovan then she is still carrying the gene for Cordovan coloration.[/QUOTE]
humm.. it seems to me you haven't got your bee genetics/ bee reporductive physioliogy quite correct here. or perhaps are you intermixing F1 and F2 phenotypes somewhat?
first off given the trait is recessive the possibility of a cordovan queen mating only with condovan drones (without the use of AI or II) would be extremely low. in a more natural mating regime if sperm is mixed in the spermathea (as is reported) then progeny would be just as mixed and/or just as homogenized as the sperm.
the genetics of the honeybee suggest that the drones should be a direct reflection of their mother and there should be cordovan no matter what the breeding. workers on the other hand should somewhat reflect the queens breeding although you might expect some variation based on how the egg forms (the genetics within the formation of an egg prior to being fertilized). If you had a copy of Laidlaw's Contempory Queen Rearing I could thumb back thru this book and give you the page reference?
I am, of course, having a wide mixture of Filial generations, F1, F2, etc. (I will sometimes select a mother queen from the most promising F2 queens, or F3, etc.) and inevitably some out breeding since I am not yet controlling my queen's matings with I.I. I am not expecting to get Cordovan queens that have been mated purely with Cordovan drones, since I am open mating, but I have hoped to have some Cordovan drones mate with my queens, and experience has shown that this is happening. Most Cordovan queens I have produced show a mixture of normal colored and Cordovan colored workers.
However, if a queen shows Cordovan coloration, then she is homozygous for the Cordovan trait and all of her drones will be Cordovan. But if she only carries one of the genes for the Cordovan coloration, then only half of her drones will be Cordovan and the only workers/queens that will be Cordovan are those that get both a Cordovan gene from her and one from their drone father. Since I am only able to control the purity of my queens, by keeping only those queens that show Cordovan coloration, their female progeny are usually a mixture of Cordovan and non-Cordovan colored, as I would expect since they are surely mating with a wide assortment of drones.
By discarding queens that are not homozygous for the Cordovan coloration I can maintain a Cordovan matriline. Of course, if I eventually have pure Cordovan queens which have only mated with non-Cordovan drones then I will be unable to maintain that line (no more females produced that are homozygous for the Cordovan trait). To restore it I would either need to import Cordovan queens that had been mated with Cordovan drones or produce Cordovan drone mated queens using I.I.
Of course, if my Cordovan drones mate with a wild AHB queen (though this may be unlikely due to the nature of AHB), and she then produces a daughter queen carrying the Cordovan gene, then half of that daughter queens drones will be AHB Cordovan. That would likely mess up my plans. However, I've been doing this for several years and less than 1% of homozygous Cordovan queens, even when mated with only non-Cordovan drones, where all their female progeny are non-Cordovan, have shown any obvious AHB traits.
I have read that the preponderance of AHB traits are carried in the paternal lineage rather than the maternal lineage -- I would quickly cull (especially the queen and drones) of any Cordovan colony that produced Cordovan workers that demonstrated any AHB traits.
Last edited by Barry; 10-19-2009 at 10:08 AM.
Reason: remove quotes