الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The work presented in this thesis was, conducted on the plum scale
insect, Parlatoria oleae (Colvee), infesting pear, plum and apple trees, at El-
Quanater El-Khairiya, Menia El-Kamh and Nobariya locations, representing
three Egyptian governorates, from Januaiy 1993 to December 1995, to study
the population abundance of P. okae on the three studied host plants, the
effect of tree heights and cardinal directions on its distribution, the effect of
some meteorological factors on the insect abundance, susceptibility of pear,
plum and apple trees to infestation with the concerned insect, also
susceptibility of the plum varieties to infestation, survey of natural enemies
associated with the insect infestation at the three studied locations, studies on
the main parasitoid of P. oleae, Aphytis maculkornis and factors affecting the
rate of parasitism, the effect of some tested insecticides on the plum scale
insect, and finally, the effect of the same tested insecticides on the parasitoid,
consequently, on the rate of parasitism. The obtained results may be
summarized as follows:
1- Population Abundance of P. oleae:
A- On pear trees, at El-Quanater El-Khairiya location:
a- Seasonal fluctuations in total population:
Two peaks of seasonal abundance were determined, in May (highest
peak of an average of 10181 individuals/30 branches) and September (8162/30
branches). The lowest abundance occurred during January, February and
August (3004, 2821 amd 3780 individuals/30 branches, respectively). The
monthly rates of change in the total population were also recorded and
indicated highest increasing rates in March (an average of 1.94) and
September (2.17), while the severest decreasing rate was recorded in June
(0.62).
b- The adult, non-ovipositing females fluctuations:
The non-ovipositing adult females showed two peaks of abundance, in
June (an average of 3249 individuals/30 branches), and in November (higher
peak of 4725), accompanied also with high rates of population increase (2.8
and 1.22 in June and November, respectively). The severest rate of decrease in
population was recorded during May (average rate of 0.61).
c- The ovipositing females fluctuations :
Two peaks of population abundance were also recorded, in April (an
average of2056 individuals/30 branches), and September (1660/30 branches),
while these insect individuals completely disappeared during January and
December, and of very low abundance during February and November. The
highest increasing rates were detected in March (16) and August (2.84),
whereas the sharpest rate of population decrease occurred in October, being of
an average of 0.3.
d- The nymphal stage fluctuations:
This stage also showed two peaks of abundance annually, in May
(7522/30 branches), and September (4094/30 branches), whereas this stage
was completely absent during December and January, and in few numbers
during February. population was found to be badly affected by the high
temperature of August, also by low temperature of January, February and
December. The highest rates of nymphs increase occurred in April (average of
4.04) and September (3.89), whereas the lowest rates were detected in June
(0.31) and November (0.24).
e- Number of generations on pear trees, at El-Quanater EI-Khairiya
location:
Depending n the relative abundance of nymphs in relation to the total
population of P. oleae, the insect mostly, has three integral generations per
year; the first starts in March and reaches its peak of abundance in May,
subsequently ends in June. The second starts in June, reaches its peak during
July and ends in August, while the third starts during late August and
continuous to the next February or March, as adults hibernate during winter as
gravid females.
f- Age-structure of p. oleae on pear trees:
The non-ovipositing females were the most abundant individuals
throughout the year (constituting average of 47.14- 48.03 % of the total
population), followed by the nymphs (36.94-37.77 %) and the ovipositing
females, which comprised about 15.13 % of the total population.
B- On phi in trees, at El-Quanater El-Khairiya location:
a- Seasonal fluctuations in total population:
Two main peaks of total population abundance were recorded, in May
(often average of 3974 individuals/30 branches) and September (highest peak
of 4258/30 branches), indicating an opposite situation to that occurred on pear
trees. The lowest insect total population occurred in February, being as an
average of 1327 individuals/30 branches, respectively. The highest rates of
increase occurred during March (2.20) and September (2.24), while the
severest rate of population decrease was in December (0.63).
The adult, non-ovipositing females fluctuations :
Two peaks of annual activity were detected, in June (where an
average of 1343 individuals/30 branches), and in November (highest peak of
an average of2919/30 branches). The lowest populations of these individuals
were detected during April (534/30 branches), May (500/30 branches) and
August (637/30 branches), as an average of the three studied years. The
highest increasing rates were recorded in June (2.77) and September (1.93);
while the severest rates of decrease were observed during April (0.60) and July
(0.61).