الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This work considered as a trial to know the cotton leafworm moth behaviogr, consqunetly
understanding the communication system of this insect •
So, the morphological and electrophysiological evidence
of antenna odor chemoreceptors were studied •
Chapter I contains the introduction and review of
literature for essential recent work in the field of
chemical communication •
Chapter II deals with the scanning electron
microscope and electroantennogram methods which are
used in the present work • It also, contains full
description for the techniques of rearing of
.§.littoralis, glass microelectrodes,and the:coating of the
metel electrode •
Chapter III concerns the obtained results
and is divided into two main parts •
I. Identification and distribution of sensilla on
S.littoralis antennae by scanning electron microscope.
The first 5 proximal segments of the
flagellum have scales present on nearly all surfaces,
while on the higher segments, scales are restricted on
the dorsal surface • The ventral and lateral surface
are! covered with a network of micro-ridges among
whi~h most antennal sensilla are located The only
evipent sensilla present under the scales were sensilla
sq~amiformia •
Eight types of sensilla are localized on the antenna •
These are, three morphological types of sensilla
trichodea 1,11,&111 which can be easily distinguished by
their dimensions and curvature • Small chemoreceptor
pegs are characterized by the cone-shaped sensory
structures • Sensilla chaetica are present on all
segments of flagellar antenna and divided into two
types I & II. Sensilla squamiformia occur under the
scales, bedded in a socket • Sensilla auricillica are
concave, small and thin-walled, it is ear-shaped in
outline. Sensilla styloconica recognized by its
reticulated base, a relatively smooth stalk, and
a conical extremity. Sensilla basiconica a short peg
is characterized by a blunt tip. Sensilla coeloconica
there are two morphological types of these sensilla
I & II (pig like sensillar apparatus recessed in
a cuticular pit ) •
2. betermination of the main functions of some sensilla
py electroantennogram technique • !
The I obtained data could be summarized under the I!
fol~owing topics :
2.1. Effect of NaCl on the recorded electroantennogram.
The S.littoralis moth,s activity is low in
both NaCl concentrations of 0.5 and J.O M . These
concentrations may be used if one wants to study the
effect of other agents on the EAG of sensillum •
The 3.0 M NaCl was chosen in this work since it is
the best stimulator and good conductor which used for
stud1ng the effect of sex pheromone and odor chemical I
substances on sensilla •
2.2. Effect of KCI on the recorded electroantennograrn •
Similar general trend of response to those
obtained by using NaCl • Also, the response of sensillum
tr~chodeum is higher than the response of small
chemoreceptor peg, while the difference in response is
always slight and insignificant •
2.’. Effect of CaC12 on the recorded electroantennogram.
Generally CaG12 appeared of much less
st~mulating activity at the tested concentrations
compared with that obtained by using NaGI and KGl •
Th¢ frequencies and amplitudes of the EAG recorded
fr~m the two sensilla (trichodeum and small chemoreceptor
pe$) one can notice that they have the same form of
ch~e •
2~4. Comparison between the effect of Nael, KCl & caC12
On the EAG of antennal sensilla of S.littoralis~
T~e least activity of the sensillum trichodeum was
~¢corded by using dalcium chloride solution, while
the highest activity occured with sodium chloride
solution. Other while, at higher concentration of the
KCl and CaCl2 the amplitudes of the EAG became much
higher than those obtained by using the same concentrations of NaCI •
2.5. Effect of the attractant female sex pheromone on
-S.littoralis male moth.
Sensilla trichodea of male antennae was very
sensitive to sex pheromone, while in female this
sensillum did not respond during passing a current
of sex pheromone •
Small chemoreceptor pegs were not stimulated
by passing the sex pheromone odor neither in male nor
in female antennae
By using sodium chloride solution as a conductor, the
highest response of sensillum trichodeum to sex
pheromone was induced at NaCI concentration of 3.0 M •
The increase in concentration of sex pheromone
between I and 5 mg was not accompanied with increase
in response •
2.6. Effect of the odor chemical substances OD both
sexes of S.littoralis •
Sensilla trichodea on the antennae of female
§.littoralis were found sentitive to amyl acetate as
c~emical stimuli • While in male antennae sensilla
t~ichodea did not respond to it -. j _.
o~ the other hand, small chemoreceptor pegs in both
male and female were sentitive to amyl acetate as
chemical stimuli •
Also, sensilla trichodea and small chemoreceptor pegs
in female were sentitive to ethyl butyrate as
chemical stimuli •
2.7. Effect of sound on sensillurn chaeticurn on the
antennae of both sexes of S.littoralis •
Sensillum chaeticum responded to mechanical
sounds and no differences occur between female and male •
Chapter IV concerns the discussion and
conclusion :
This chapter shows that -the electroantennogram
technique could be considered as. method ~or the
determination of the functions of sensilla •
The functions of three types of sensilla in both
sexes were detected as follows :
(A) In the male moths of S.littoralis, sensilla
trichodea type I act as site receptor for the female
sex pheromone • However, in female these sensilla
function as olfactory receptor for the odor from
chemical substances such as amyl acetate and ethyl
butyrate. This result may consider sensilla trichodea
in female associated with the location of a suitable
oviposition site by gravid female.
(B) In both sexes of S.littoralis sensilla small
chemoreceptor pegs function as site olfactory
receptor for the odor of chemical substances, such as
amyl acetate and ethyl butyrate •
(C) In both sexes of S.littoralis, sensilla chaetica
are concerned with mechanoreception.
(D) from the result of the theoretical study, it was
found that the number of neurons which is expecte~ to
innervate the small chemoreceptor peg is about 50 times
greater than that needed for the sensillum trichodeum.