الفهرس 
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Abstract
The present studies were carried out in the apiary and laboratory of
Faculty of Agriculture Moshtohor, Zagazig University.
The results of these studies indicated that, the fungi are
commonn saprophytes and some others are parasites of bees and
combs. Isolation studies of different fungi performed on
different stages of honeybee (larvae and adults yielded 90 fungi
including 5 genus belonging to 7 species. These funguses were
Ascosphaera apis, Alterinaria tenuis, Aspergillus niger A.
paraziticus, A. terreus, A. wentii, Hormodendurm sp., and
penicillium chrysogenum. Data indicated also that larvae were
highly infected with Ascophaera apis, but it is not associated
with honeybee adult of Apis mellifera. However honeybee
adult were highly infected by many other saprophytic fungi such
as, Aspergillus niger, A. paraziticus terreus and Alternaria
tenuis. It was found that there were two major fungi that affect
honeybee colonies the first was Ascosphera apis the causal
organism of chalkbrood disease. The diseased larvae which
infected by A. apis was overgrown by fluffy cottonlike and
swell to the size of the cell in brood combs. If strain of
mycelium is present. the larvae dries into • hard Ihnmkon. white
chalk like mummy, hence the name of chalk brood, mummies
can be found at the hive entrance or on the bottom board. This
disease is a major threat to beekeeping and causes a great
economical loss to bees’ product and the..d. isease incidence is
increasing in Egypt. The second species of fungus disease is
stonebrood that caused by Aspergillus spp.
. The identification of fungus from pure isolates of mummies larvae,
infected larvae and other honeybee colonies in Egypt were carried out in
National Research Center (NRC), EI-Dokky, Giza, Egypt. The obtained
results indicated that the chalkbrood is a disease of honeybee larvae
caused by the fungus Ascosphaera apia.
The obtained results could be summarized as follows:_
1- Survey of chalkbrood disease A. apis found in Qualubia
Governorate:
The results of <fungus (Ascosphaera apis) survey in honeybee
colonies especially in Qualubia governorate indicated that 399 honeybee
colonies out of 6260 colonies examined were infested with chalkbrood
diseases during the two years of study (1996-1997). The high percentage
of infestation 9.0 % during (1996) was detected in EI Quanater EI
Khairia. However it was found that Qualiob district had the high
percentage of 7.S % during 1997 season.
The mummies that resulted from the infection by cha1kbrood disease
in honeybee colonies’ were counted outside & inside, and on the bottom
board of the hive. The mean average numbers of mummies during two
seasons (1996 &: 1997) was 48.15/colcny. The highest mummy numbers
However average number of mite in other healthy colonies found in the
hive debris were 589.-1/colony during the periods from February to June
(1996 & 1997).
3- Effect of honeybee colonies by chalkbrood on brood
rearing activity: -
The study of the effect of chalkbrood on the areas of infested comb
in ten honeybee colonies/Cinch) 2 located at the Faculty apiaries measured
at 12 days intervals during periods of March - July (1996 - 1997)
indicated that the total area of infested brood was 587 (inch) 2. The mean
area was 58.7 (inch) 2 and the mean of infested percentage was 27.9%
per colony. However the total areas of healthy brood in infected colonies
were 2098 (inch) 2) and the mean of healthy brood was 209.8 (inch) 2.
However the total areas of healthy brood (control) in healthy colonies
were 6686 (inch) 2 and the mean was 668.6 (inch) 2 during the two years
of study (1996 -1997).
4- Effect of different seasons on honeybee colonies infection
with chalkbrood disease: -
The mean numbers of honeybee colonies that infested with
chalkbrood disease were estimated monthly from February to September
during seasons (1996 and 1997) at the Faculty apiaries. The results
indicated that infested colonies with chalkbrood disease Ascosphaera apis
clurin& 1996 and 19971’1Dpcl from 7 IDd 5 1nSeptember to 45 end 40 in
April respectively. It could be concluded that throughout the study) that
the high infestation with chalkbrood was during April in the two seasons
of 1996 and 1997, in the other hand the lower infestation was in
September.
5- Effect of chalkbrood infection on honey production: -
The mean amounts of honey produced from infested colonies
during the clover and citrus seasons in 1996 and 1997 was 0.83 and
0.64 kg/colony respectively. However the amount of honey
produced in healthy colonies (control) at the same seasons was 4.33
and, 3.49 kg/colony. The infested colonies with chalkbrood disease
gave the range loss of honey production in 1996 and 1997 seasons
from 70 and 66.6 % to 94 and 92 % respectively. The mean losses of
honey production were about 80.5 and 81.5 % when compared with
the healthy colonies in 1996 and 1997 seasons respectively.
6- Effect of some important bee management operations on
protection of honeybee colonies and controlling
chalkbrood disease during the nectar flow seasons of
1997 and 1998.
A- The effect of Queen age on the rate of infection of
honeybee colonies by ehalkbrood.
The experiment and observation indicated that, the colonies having
old queens (more than 3 years old) were infected with cbalkbrood disease
more than the colonies that having the newly matted young queens. The
mean of 28.7 % was obtained in from colonies with old queens. The
highest percent of infestation 40, 35 and 30 % occurred in March,
September and April, respectively. However the colonies that having the
young mated Queens (less than 1 year old) were healthy and the
chalkbrood infestation were very low. Only one colony showed a 5 %
infestation during March, with a total mean infestation of 0.01 %.
.B- The study of the effect of introducing newly matted queen into
chalkbrood infected colonies: -
These results indicated that replacement of old queen by a newly
matted queen stopped the disease and the colonies became stronger. The
disease disappeared after about two-month from introducing the young
new queen and the colonies regained its strength and became healthy and
strong in rearing activity.
c- Effect of re-queening of honeybee colonieswith young queens on
.brood rearing activities, protection and controlling of colonies
from infection by chalkbrood disease: _
The results indicated that introduction of a young newly matted
queen to the colonies enhanced there breading activity and reared more
brood than the colonies with old queen. The mean areas of sealed brood
reared in colonies headed with young mother queen were 2020.6, 1944.1
and 2166.2 inch2/colony. However the mean sealed brood reared in
colonies headed with mother queen more than three years old were 463.4,
480.5 and 561.5 inch2/colony.
D- Effect of artificial feeding and pollen supplement of honeybee
colonies on the infection percentage by chalkbrood disease: _
The effect of artificial feeding on stimulating, protecting colonies
from chalkbrood disease and increasing honeybee activities during dearth
seasons of 1997 and 1998 are presented in table 12. The obtained data
indicated that Colonies fed on sugar syrup and provided with pollen
supplement (brewer’s yeast), had only 1.0, 1.0, 2.0 and 1.0 infected
colonies out of 25 colonies in February, March, April and May,
respectively. However colonies fed with sugar syrup only had 3, 4, 3, 5,
5, 4,4, 5, and 5 infected colonies out of the 25 observed colonies during
January,February,March,April,May,June,July,AugustandSeptembe~
respectively. The mean of infected colonies was 4.2 colonies. The
infestation percentage by chalkbrood disease in colonies fed with sugar
syrup only was 16.9 %. However the infection percentage in colonies fed
with sugar syrup and provided with brewer’s yeast was 1.3 % only. This
result shows significant differences between treatments.
It is obvious from the obtained results that colonies fed with sugar
syrup and brewer’s yeast during the dearth seasons produced and reared
bees and give a stronger colonies more than colonies fed with sugar syrup
only. The mean infestation percentages were 1.3 % and 16.9 % for colony
fed with sugar syrup and brewer’s yeast and colonies fed with sugar syrup
only respectively. Supplying colonies with brewer’s yeast and sugar
syrup increased colony strength, increased the resistance ofbee colonies
to chaIkbrood disease, strengthens the bee colonies, and protect it from
chalkbrood disease.
7- Control of chalkbrood in laboratory: -
The effect of four substances on the linear growth of A . apis showed
that formaline was only effective and inhibited the growth of this
fungus at different concentration. The rates of growth were less
completely inhibited by both Ultragriseofulvin and Neem extracts. The
growths were inhibited at very low rate with propolise. The effective
substances are formaline at low concentration of 10 % followed by
propolise then Ultragriseofulvin and Neem.