Tracheal Mites May Be Honey Bee Color-Coded?
by Jim HOLLAND,
Lisburn, Northern Ireland.
Am. Bee J. 131(8) 1991 p507-508
|[Return to Biblio]|
There is an increasing volume of evidence that the devastation now being caused by tracheal mites in the honey bees of North America can be linked directly to the particular color of the bees that are susceptible to the ravages of Acarapis woodi.
This would not be surprising to the students of human genetics for it has now been established that even some human diseases can be the fault of a particular gene which may be linked for example to melanin, or the absence of it, the agent responsible for causing brown or black pigment in hair. In some cases it may be traced to a particular gene which is on the same chromosome as a gene for colour. Or, as a result of a deficient enzyme, a chain reaction may occur which links the particular disease to a person with grey hair.
In the case of the honey bee, Brother ADAM of Buckfast Abbey, through his work that has been in progress for over more than half of this century, has established the susceptibility of „Golden“ or „Bright Yellow“ honey bees to acarine disease. This linkage of the susceptibility of bright yellow or golden honeybees to Acarine has been established at Buckfast as far back as 1925. Formerly, it was widely assumed that the Golden Italian variety was derived from a cross between the Cyprian and Italian. However, the whole Egyptian group of races is orange, not yellow. According to the findings of Brother ADAM, the „Golden“ variety derived its origin from a cross between a dark western European variety and a common yellow Italian. The yellow was intensified by selection in the course of time. It was Allan PRATT of Pennsylvania who first bred a golden strain some few years before the end of the last century. Mr. SLADEN, at the beginning of this century, endeavored to develop an English Golden variety. During the course of his experimental crosses, the exceptional susceptibility of the „Golden varieties“ was discovered by Brother ADAM in 1925. The dominance of this susceptibility to acarine when such colored bees were crossed to a highly resistant strain such as the Buckfast was confirmed again in 1959. If further confirmation were needed, this was established at Buckfast by means of instrumental insemination of New Zealand sperm supplied by Dr. John HARBO of Baton Rouge in 1972. The knowledge, therefore, that such strains were dangerously susceptible in areas where tracheal mites were found has been around for some time.
It would at this stage be relevant also to add that in Ireland, while the devastation from acarine still continues, although nowhere on the same scale as in the USA, it is largely affecting those bright yellow bees which have been imported, particularly in Northern Ireland. Over the past 20 years, on the other hand, in my own apiaries with exclusively Buckfast bees, and confirmed by laboratory examination, acarine has been unknown. This is confirmed without the application of any medications, and in the presence of wide-scale local infestations of the mites.
However, apart from these preliminary remarks, the purpose of this article is to provide a wider platform for a paper by Brother ADAM which was delivered in his presence to the Nova Scotia Beekeepers‘ Association at their annual conference in Kentville in March 1991. In this paper Brother ADAM addresses not only the problem of acarine, but that of Varroa jacobsoni as well. While he has in no small measure overcome the former problem, given the added years (he is now in his 93rd year), I have no doubt that he would be well on the way to resolving the latter problem as well. Brother ADAM has kindly given me permission to publish the text of this paper in full.
Whether there is a recessive gene at work which surfaces when the honey bee is bred until it reaches the „Golden“ stage, or whether some other physiological agent is in force which predisposes the honey bee to devastation by mites is an academic question. This is not to dismiss the word in the sense that it is „merely academic“, as if it were of no practical importance. On the contrary, students of Brother ADAM’s work will find no dichotomy between what is „academic“ and what is of the most important „practical“ considerations. For his contributions, two universities, one in Sweden and one in England, have awarded him the degree of Doctor of Science.
It is therefore a matter of concern that in relation to the susceptibility of honey bees to acarine disease, which Brother ADAM established so early on in this century, his findings appear to have gone, either unheeded or ignored. The results secured in Europe, based on wide experience in the field and confirmed by instrumental insemination leave no doubt or room for uncertainty. For the beekeeper interested in practical results right now, his paper is worthy of close attention.
realization : Jean-Marie Van Dyck – Namur Belgium