الفهرس 
EXPER.IMEN’l’AL RESULTSOnly 14 pages are availabe for public view
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Abstract
A- Behavioural Studies:
1- Courtship behaviour:
Laboratory observations of the courtship behaviour of W. nuba
flies showed a series of male action patterns directed towards a
female which could described as follows: Male oriented himself
towards the female, vibrated rapidly both wings horizontally in an
outward, backward direction to the resting position. Male extended
and rubbed fore legs to and fro against his abdomen or against each
other or, against the side of head. Male came nearby the female
tried to get in contact with her. Male circled about female, male
jumped on the back of the female, curled the tips of the abdomen
under the female abdomen, grasped her body with his fore and midlegs and attempted intermission.
2- The relat
their
between the sexual act of males and
The sexual activity of male increased as the age of male
increased. The percent of mating is 6.6% at age 0-4 hrs and 93.3% at
age 3 day-old. Four day-old male displayed a high level of male
activity reaching 100% and remained constant until male was 10
day-old. In other words, male flies did not attain their maximal
level of responsiveness to the odour of females until their 4 th day
after emergence.
Statistical analysis showed that there was a strong correlation
between male age and percentage of mating. Also the sexual activity
of male significantly increased with male age,
3- Effect of diet on the mating activity :
The adult did not require lipid or proteinous diet in order to release or respond to the courtship
stimulating odour .
4- Effect of repeated mating upon frequency and duration of 9opulation:
The ability of males to remate decreased in successive mating. The percentage of male remating
between the second and seventh copulation was sharply reduced from 80% to 12%. Also the mean time
required for mating increased and ranged from 3 to 16.5 minutes in all the consecutive matings,
although very slight difference was obtained in the average time spent in copula.
No significant difference was recorded in the average time spent in copula in the male consecutive
matings . A signif icant decrease was obtained in the percentage of male remating with the male
consecutive matings, whi le a significant increase was recorded in the mean t ime
requ i red f or mat ing w i th t he male consecut i ve
remat ing.
5- Interrupted matinll’_.and the effect of length of copulation on the degree of insemination :
The percentage of insemination increased with the increase of the time spent in copula, and reached
its maximum value after 3 minutes. Thirty seconds was the time required for sperm transfer although
the percent of insemination was 20%. Meanwhi le, the average number of deposited larvae also
increased.
Statistical analysis showed that there was a strong correlation between the time spent in copula
and the percentage of insemination. Also, the percentage of inseminat ion and the average number of
deposited larvae significantly increased with the increase of the time spent in copula.
6- Effect of age and mating status of female on mating behaviour nd pheromone production :
The percentage of mating receptivity among newly emerged females (0-4 hrs.l was 86.3%. Meanwhile
the mating receptivity of females (1 day-old) decreased (78. 3%) when compared to newly emerged
females. This decrease was followed by increase in the mating receptivity as the females increased
in age reaching its maximum value 100% at age 7 and 11 days.
Meanwhi le, the remating receptivity started with 17.7% at 1 day-old female. This remating
receptivity incr·eased as the period after original mating increased reaching, its maxi mum value
(100%) at age 7 days, then slightly decreased (95%) at age 11 days.
Statistical analysis showed that there was a strong correlation between the percentage of remating
and state of female, also, the percentage of remating significantly increased with the increase of
period after mating.
7- Polygamy in female W. nuba:
The females had the ability to remate more than once during their life span. There was an inverse
relationship between the number of matings and the percentage of remating.
The percentage of female remating significantly decreased with the increase of the number of
matings .
8- Effect of time of copulation on the percent of remating of female:
The insemination of females did not influence its sexual receptivity . The longer the time spent in
copula, the fewer the remated females.
Statistical ·analysis showed that the percentage of female remating significantly decreased with
the increase of time spent in the first mating.
9- Behaviour of decapitated and ligated females:
Remating occurred often among the females decapi tated after the first mating. The percentage of
remating among all groups of decapitated females ranged from 26.6 to 35.2% in comparison with the
control group in which none of the control females remated immediately after the first mating.
Also, there was a relationship between treated females and the lir.ie spent in copula. As the
treated females spent longer time in copula ranging between JO.4 to 55.6 minutes than the control
22.0 minutes . Moreover, there was a
decrease i n the t ime spent in copu la rang ing be tween 15 to 18. 8 m inutes
when compared t o tha t spent dur ing t he f i rst mat ing.
Chi-square analysis of these data showed tha t the percen t age of rema t ing of the
decapi ta ted f ema les signif icantl y increased when compar ed to the cont rol . Also, a
signif ican t d if f erence was recorded in the average t ime spent in copula in the decapi t
ated f emales when
compared t o normal ones.
The per centage of the f irst and second mat ing of l igated vi rgin f ema les was h igher
78. 2% and 32%, respect ively than tha t of the f emales which were Uga ted af ter t he
first ma ting 68. 7% and 18. 3%, respect ively.
10- Evidence of an a t t r act i ve r eleased the f emale
W. nuba:
Results recorded f rom t he T-shaped olf actometer tests showed tha t t he ma les were
at t racted t o f emales. A lso the percen tage of ma les response against f emales ranged
between 60 and 68%. Ma les d id no t at t r act f emales.
11- Pre .nce
:>f chem ical subst ance ( sexua l pheromone ) :
Result s obtained show that a certain chem ical substance or sexua l pheromone migh t
emana te f rom vi rgin dead f emale so tha t the ma le was at t racted f or copu lat i on
.