الفهرس 
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Abstract
S-U-M-M-A-R-YI.
Ecological Studies :
1. ~~!=~~~~!_~!_!~=_E~!~~~-!~~=~-~~!~_!~-~~!~-
naceous crops : -------------
Laboratory experiments were carried out to
determine the preference of the potato tuber moth
to potato, tomato, eggplant and pepperleaves.Results
obtained showed that the insect’s preference was
for potato, tomato, eggplant and pepper; respecti~
vely; and the pepper infestation were negligible.
2. Susceptibility of various potato varieties ~-------------------------------------------
to potato tuber moth P. operculella :
-----------------------------------
Field studies on five potato varieties were
carried out at the Experimental Station of the
Faculty of Agriculture at Moshtohor,”QalyUbia during
the years 1982 and 1983 to determine infestation
~egree of P. operculella on the potato varieties
(Kondor, Gracia, Renska, Monalisa and Vulkano).
Results obtained could be summarized as
follows :
_ ..~ ,_~ ’0_- - - ”’, ---”_._- - -
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2.1. Infestation of the foliage :
a. Severe level of infestation : Monalisa var.
b. Moderate level of infestation : Renska and
Vulkano varieties.
c. Light level of infestation : Kondor and
Gracia varieties.
2.2. Tubers infestation :
a. Moderate level of infestation : Vulkano and
Renska varieties.
b. Light level of infestation : Kondor, Monalisa
and Gracia varieties.
II. Biological Studies :
The effect of rearing P. operculella-larvae
on the tubers of potato • tomato and eggplant f’ruits
on the biological aspects was studied for 2 generations
and under four temperature 19.6, 24.5, 29.4
o
and 34.3 C and 68 % R.H.
There were significant difference between means
of the incubation periods, larval, prepupal and
pupal stages •. Shortest durations wer~ obtained when
the larvae were reared on potato tUbers, followed
by tomato and eggplant fruits •
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Results obtained induced significant difference between
means of pupal weights for larvae reared on different
hosts. The maximum pupal weight was associated with the
larvae reared on potato tubers, while the minimum one was
obtained by eggplant larval feeding. Female p~pal weights
were highel’ than male’s wh~n the larvae were fed on the
three host plants, at different temperatures.
On the adult stage. no significant difference~ere found
between means of the preovipo~ition periods. The shortest
duration was obtained from moths resulted of larvae fed on
potato tubers ,followed by those of larvae fed on tomato
and eggplant fruits, respectively. Statistical analysis
of the data concerning the oviposi tien and pe~t-oviposition
pazLoda t indicated insignificant difference
between means.
Longest adult life span were exhibited by individuals
reared on potato tubers, while shortest ones resulted
from those reared on eggplant fruits. Female longeVity
-was longer than male for larvae reared on the three
tested hosts at different temperatures.
The lowest number of eggs was obtained by femalesof
.~arvae reared . on eggplant fruits.whereas the highest
number was reported for those reared on potato tubers.
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The total life cycle of the individual reared
on potato tubers was shorter than’ on the other.
The effect of the different temperatures on the
various stages of ~. Qperculella was obvious. The
o
suitable temperature was 29.4 C for rearing the insect
and for producing highly fecundities, followed by
o 0 24.5 and 19.6 C. As for 34.) 0, this temperature
was considered unsuitable for surviving the various
stages of the insect and giving lowest numbers of
eggS/female.