FILENAME:  SEPAPIS.92
 
 
            Florida Extension Beekeeping Newsletter
    Apis--Apicultural Information and Issues (ISSN 0889-3764)
                 Volume 10, Number 9, September 1992
 
                         EXPORT HOTLINE
 
     Those interested in international trade opportunities can now
access a new information resource.  "The Export Hotline is a
corporately sponsored, nationwide fax retrieval system for U.S.
business on international trade information.  Its purpose is simple
- to help you find new markets for your products and services and
build America's exporting base."
 
     The above is quoted from the first paragraph of the beginner's
guide that is faxed to individuals after calling toll free 1-800-
872-9767.  It's easy to follow the instructions given on the phone.
Good luck and let me know of your experiences in using the system.
 
                  COMPLEXITIES OF BEE BREEDING
 
     Bee breeding is getting a lot of attention these days.  An
article in Bee Science (Vol. 2, No. 2, June, 1992) discusses the
results of a stock center survey done by Tim Lawrence and Susan
Cobey, Honey Bee Insemination Service, 7417 Hayden Run Rd., Amlin,
OH 43002.  According to the authors, most respondents indicated a
need for such a center, but how it will be paid for remains
unanswered.  The cost is likely to be high.
 
     Some might not understand what skills are involved in bee
breeding and how these might be reflected in the costs of a stock
center.  Thus, I am reprinting a slightly edited version of a
presentation on queen breeding I received via electronic mail.  It
is not likely to be published elsewhere in the United States, being
presented in July, 1992, as part of the meeting of the National
Beekeepers Association of New Zealand.  According to Nick
Wallingford, the source of this paper, it is one of the most
understandable treatments on the subject he's heard.  Finally, the
talk was given by a commercial queen breeder who is intimately
acquainted with the many practical aspects of queen production.
 
  IMPROVING OUR BEE STOCKS:  WHY IT IS SO DIFFICULT TO DO
 
                               by
 
                        Mr. D.W.J. YANKE
                         DAYKEL APIARIES
 
     The ground I hope to cover with this talk is that mountainous,
probably impassable stuff which stands between us and the ever-
elusive super bee.  The mechanics of heredity are the same whether
it be bees or buffalo.  The progeny of organisms that reproduce
sexually are not exact duplicates of their parents and vary in many
ways amongst themselves.  This variation is the spice of life.  It
is what allows a species to adapt and evolve, and also provides
plant and animal breeders with a wide array of choices.
 
     It is important to understand some of the basics of genetics
in order to comprehend much of what is said later.  The carrier of
the genetic message is DNA, a large molecule which contains the
code responsible for the structure and function of any living
organism.
 
     Genes are specific lengths of the DNA molecule, the base units
of inheritance.  Variations of the same gene are called alleles.
There may be several different alleles of a gene.  Every sexually
reproducing species inherits two alleles, one from each parent.
These interact with varying degrees on each other.
 
[Editor's note:  One allele may dominate (eliminate the effects of
the other), be dominated by (recessive to) the other, have equal
weight (co-dominant) or partial weight (incomplete dominance) with
relation to its partner, or have no effect at all].
 
     Chromosomes are cellular bodies found in the nucleus of cells
that carry genes.  Two sets of genes (made up of many alleles) are
carried on a given number of chromosomes characteristic of each
species - humans have 46, potatoes 48, and honey bees 32.  This
number is known as the diploid number of chromosomes.  The sex
cells (sperm and egg) have half the number of chromosomes and are
said to be haploid.  Honey bee drones, because they develop from
unfertilized eggs, have a haploid number of chromosomes which is
16.  In the formation of sex cells, chromosome pairs stretch out
together.  While lying close to each other, the chromosomes can
exchange portions of their DNA, which may contain one or more
genes.  This process is known as crossing over and is responsible
for most of the variation seen in progeny.
 
     When we try to make a bee stock more useful, we are trying to
select the DNA within that population - increasing the frequency of
genes responsible for desirable traits.  In doing so, however, we
affect other gene frequencies, and this can create problems.  So
the trick is to be able to modify genetic material without losing
diversity.
 
     The following are what I see to be main barriers to bee stock
improvement.
 
1.  CONTROLLING MATING BEHAVIOR
 
     When the virgin queen is about six days old, and the weather
conditions are fine, with light winds and temperatures of at least
20 degrees C, she flies out a considerable distance from her hive
to mate.  Research has shown the average distance between apiary
and mating place is two kilometers (1.6 km = one mile).  She has
been shown to fly out as far as five km.   Mating flights last
between five and 30 minutes.  She will make between one and three
flights.  The number of flights she makes depends on the
concentration of spermatozoa in her spermatheca.  Once it reaches
a certain concentration, she will not fly again.  To achieve this
concentration she must mate with several drones - at least seven,
maybe many more.
 
     The virgin does not fly haphazardly about hoping by sheer
chance to encounter drones.  She goes directly to drone
congregation areas.  Exactly why drone congregation areas originate
where they do is not fully understood, but the same areas are used
year after year.  The drones within any congregation area come from
many different colonies, and probably several different apiaries.
Drones have a flight range of up to six kilometers with flights of
five common.  Thus drones can range over an area of roughly 78
square kilometers.
 
[Editor's note:  The numbers quoted by Mr. Yanke are controversial.
Reports of drone flight distances are highly variable; queens may
mate with as many as 18 drones.  Drones actively search for queens
guided by odors (pheromones).  It is not known how or whether
virgins seek out drone congregation areas.]
 
     It has been shown that virgins very rarely mate with related
drones, which reduces the chances of inbreeding, one of the perils
to avoid in any controlled breeding scheme.   Thus, if we allow
virgins to mate naturally, we have no control over the drones.
Even with isolated mating yards, control is not absolute.  What
other plant or animal breeder has to make an attempt at genetic
improvement with only control over 1/2 of the genetic equation?  To
compound this there are multiple matings.   Each virgin mates with
seven or more drones, and thus the colony is made up of seven or
more sub-families.
 
2.  RETAINING SEX ALLELES
 
     In most sexually reproducing organisms, sex determination is
governed by a sex chromosome.  In honey bees, however, sex is
determined by a single gene.  This gene has many variants or
alleles, maybe as many as 18.  One should feel lucky, however, to
maintain 10 or so in a breeding population.   It works like this,
if two different alleles come together at fertilization, a female
(worker or queen) results.  Drones are haploid and have one allele.
However, if two of the same allele come together, a diploid male
results.  We never see diploid drones in the hive because when only
a few hours old, they are cannibalized by the workers.  Evidence of
this is a hole (spot) in a slab of newly capped worker brood.
 
     As the number of sex alleles decreases, the more likely it is
that two of the same allele will come together, increasing the
number of diploid drones.  As the percentage of diploid drones
produced increases, so does the spottiness of the brood.  There is
an obvious impact on a colony's productivity, therefore, when some
well-intentioned bee breeder reduces the number of sex alleles in
a queen.  Even if such queens are of high physiological quality and
genetic potential, they are handicapped because a percentage of
their eggs are not viable.
 
     The mechanics of heredity and the mating behavior of the honey
bee, therefore, are geared to genetic diversity.  The mechanism of
sex determination in honey bees also penalizes any narrowing of
this natural diversity.
 
3. REDUCING INBREEDING DEPRESSION
 
     Hybrid vigor results when two unrelated members of a species
are crossed.  The vitality of the progeny usually exceeds that of
either parent.  This is also known as heterosis, a mostly
unexplained increase in life force.  The crossing of unrelated
parents results in many more genes carrying two different alleles.
When a pair of genes consists of different alleles the resulting
organism is said to be heterozygous.  A generalized increase in
heterozygosity is responsible for triggering heterosis.  The
opposite state is when genes carry two of the same allele.  These
organisms are said to be homozygous.
 
     A reduction in heterosis occurs with inbreeding.  An
"inbreeding depression" is triggered as the percentage of
homozygous genes increases.  This results in an unexpected loss of
vigor--sluggish colony build-up, loss of disease resistance,
decreased production, and higher winter loss.
 
     Inbreeding depression can result from selections over
generations for the best genetic combinations.  The breeder's
downfall is increasing the percentage of homozygous genes in too
small a population.   This is not always apparent to a producer who
is selecting breeders from perhaps hundreds of colonies.
Unfortunately, it is not the size of the test population, but the
number of breeding queens used, which determines how quickly
inbreeding depression develops.
 
4.  MAXIMIZING QUANTITATIVE TRAITS
 
     The characteristics we are trying to improve in honey bees are
quantitative traits.  These may involve many genes, each
contributing only small effect.  Compounding this is the fact that
these traits are not those of a single breeding individual (the
queen) but, instead characterized in a colony composed of many
sub-families.
 
     It is fortunate that many important economic traits such as
honey production and winter hardiness in bee populations, even
though they are hugely complex, and controlled by a large number of
genes, do show good response to selection.   However, once these
selections cease, any increase in traits which has been achieved is
lost very quickly as gene frequencies return to pre-selection
balances.  Thus, maximizing quantitative traits is a continuous
process which must be done with great care.
 
5.  MINIMIZING ENVIRONMENTAL VARIATION
 
     Evaluations must reliably identify the genetically superior
individuals in the test population in order to increase
quantitative traits.   However, because colony performance is
evaluated in the field, it is difficult to control environmental
influence.  Possibilities to reduce environmental effects consist
of equalizing colonies before evaluations begin, minimizing drift;
and eliminating evaluations between apiaries.  Finally, because a
queen's physiological quality itself can have a major effect on
some aspects of colony performance, queens undergoing evaluation
must be uniform in age and condition.
 
6. MINIMIZING THE INFLUENCE OF RACIAL HYBRIDS
 
     Even if we implement all the suggestions above, and put into
evaluations the care and effort required, it is all for naught if
the genetic superiority we identified with our evaluations is not
heritable.  Unfortunately, the increased vigor provided by
heterosis cannot be inherited.
 
     We have two races of honey bee in New Zealand, the Dark
European honey bee and the Italian.  Even though most of the bee
breeding effort goes into maintaining commercial bee stocks as
Italian, the reality is that most of the colonies are to varying
degrees racial hybrids.  Racial hybrids can be great, and through
hybrid vigor, are often productive.  However, they are of no
breeding value, and provide only false leads to someone carrying
out colony evaluations.
 
   To get anywhere, we have to breed true to race -- whatever that
race is.   The Dark European honey bee drones appear to be very
aggressive in the drone congregation areas because they appear to
have a mating advantage of almost Africanized-bee-like proportions.
So the only way to keep a test population true to race is to have
absolute control over the mating using Instrumental Insemination.
 
7.  KEEPING AN OPEN MIND
 
     It may be a lot cheaper to import a silk purse, than to try
and make one out of a sow's ear.  Taking advantage of different
races and breeding work done overseas by importing genetic material
could save time and money and be a dramatic shortcut to better
bees.  Times have changed, importations of genetic material can be
done safely, whether they be semen or breeder queens.
 
[Editor's note:  This remains controversial.  Stock importation is
illegal in the U.S.  It has traditionally been responsible for
worldwide dissemination of diseases and pests.]
 
8.  KEEPING ON THE ROAD TO BETTER BEES
 
     It is possible to breed better bees.  Results of 23 years of
selections in Germany with Carniolans demonstrates this.  The
progress was slow, but it was progressive, and it was done without
the recent research into closed population bee breeding.  Results
of this technology are more impressive.  As an example, the Western
Australian Department of Ag. bee breeding program which ran from
the mid-80's up until this year realized a 10% increase in honey
production per year.  There is a similar program up and running in
N.Z.  It is totally self-funded by its participants, and has a
legal structure of a limited liability company.  There are 25
participants and each is an equal shareholder in the company.  For
their investment, they receive improved breeding stock.
 
     The New Zealand program's goal is to improve an Italian-type
bee in a closed population, maintaining 25 lines - one for each
participant.  Matings are absolutely controlled using instrumental
insemination. The semen is collected in equal volumes from each
line, then pooled together and homogenized.
 
     The program's structure has all the necessary ingredients
leading to better bees.  The foundation stock was contributed from
all over the country to maximize genetic diversity, and once the
population is closed off, maintaining 25 lines with mother daughter
replacements each generation means that the program can run for
more than 25 generations without the introduction of any stock from
outside the program and still maintain sufficient diversity to
avoid any ill-effects from either homozygous sex alleles or
inbreeding depression.
 
     The use of pooled and homogenized semen has been a most
important breakthrough in bee breeding.  It maximizes genetic
diversity and selection pressure.  The semen dose each queen
receives represents all 25 lines being maintained in the program.
Because the semen, although amazingly diverse, is homogeneous,
each queen receives an equal genetic dose. Therefore, any genetic
variation uncovered by the evaluations, is maternal in origin.
This gives the selections more meaning, increasing the potential
rate of improvement.
 
     Instrumental insemination makes maintaining racial purity a
piece of cake, you just don't collect semen from darkish drones.
Selections for winter hardiness and honey production are carried
out in two parts.  The first part is done by the participants, and
is more broadly based.  Each participant receives the daughters of
one line in mid--February each year. They are introduced into
equalized units and equalized again in April.  The queens are
evaluated for their overwintering ability using the criteria of
colony weight loss between May and September (New Zealand's
winter).  They are also scored on brood viability, temperament,
hygienic behavior, and color.
 
     In late September, the participants choose the two best
queens, based on the above evaluations, to be introduced into hives
in one large dispersed apiary.  They are equalized and in December
(New Zealand's summer) and evaluated for honey production potential
using short-term colony weight gain.  An initial and a final weight
are taken 10 days apart.  The queen which performed best for each
line is chosen and becomes the breeder for the next generation.  10
daughters are reared from each breeder and these are inseminated
with pooled semen.  It is these daughters which form the test
population for next season's evaluations.  The author of this paper
can be contacted directly at: PARANUI RD3, KAITAIA, NEW ZEALAND.
 
     [Editor's conclusion:  For the United States, it would seem
that only some organization on the order of a stock center proposed
by Lawrence/Cobey would be capable of a continuous selection
program similar to the one now in place in New Zealand.  However,
it must be supported philosophically and financially by U.S.
beekeepers if it has any chance of succeeding.]
 
                  FLORIDA STATE BEEKEEPERS MEET
 
     The annual meeting of the Florida State Beekeepers Association
is November 5,6,7.  It will be held at the Holiday Inn North of
Sebring, FL.  For details, contact the Secretary-Treasurer,  Ms.
Eloise Cutts, 2237 NW 16th Ave., Gainesville, FL 32605, ph 904/378-
7719.