الفهرس 
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Abstract
These studies on the integrated control of the citrus leaf miner
Phyllocnistis citrella Stainton were carried out in Citrus Orchards in
Qalubia Governorate, during two successive seasons. It is aimed by
the present study to explore all practices which may be minimize the
population of the citrus leaf miner (CLM). Each factor was tested
alone and finally the suitable of it were chosen in integrated
programme depending on the activity of factors to control P. citrella.
Citrus fruits considered the most important fruits in Egypt either for
export or local consumption. The area of cultivated fruits in Egypt
ranged between 950,000 to 1000,000 feddan, 40% percentage of this
area citrus orchards. The citrus leaf miner is the most important pest
which attack the citrus orchards. In this experiment, samples of 20
leaves/ each were weekly collected from each experimental unit
.Larvae and pupae and also the infestation rate with eLM was
calculated to evaluate the effect of different factors and the ability to
introduce it in integrated control program to citrus leaf miner. The
evaluated control methods were tested in relation to citrus leaf miner
(eLM, P. citrella) infestation to mature navel orange (Citrus sinensis)
and sour orange trees and seedlings (c. aurantium). The majority of
new leaves in spring were never infested but that in summer and
autumn were highly infested with this respect pest. The obtained
results are, briefly summarized in the following:
Summary and Conclusion
1. Chemical control:
Three chemical treatments (Vertimec + KZ oil, Confidor and
Admiral) were tested against P. citrella with two concentration
(recommended and half-recommended). The results of the efficacy of
tested compound revealed that Vertimec + KZ oil with recommended
and half-recommended concentrations gave the best results to control
the citrus leaf miner. The mean reduction rate was 75.26% and
67.99% and the residual effect was the longest (21 days) within all
other treatments. Confidor with recommended and half-recommended
concentration was less effective than Vertimec + KZ oil with the
mean reduction rate was 63.82% and 50.82%. While, Admiral with
two concentrations have lower effectiveness than Vertimec and
Confidor. Admiral with two concentrations caused 32.52% and
29.61%. reduction in larvae and pupae population. So Vertimec + KZ
oil gave the best results to control citrus leaf miner with residual effect
was the longest within all insecticides (21 days). Then Vertimec + KZ
oil was the most effective against citrus leaf miner resulting in 100%
reduction to larval and pupal population in comparison with the
control after 30 days form application, so it can be recommended to
spray Vertimec + KZ oil with recommended or half-recommended.
2. Biological control:
This course of investigation was carried out during the period
from 11 September 2003 to December 4 th 2003, in citrus orchard (sour
orange) in Qalubia Governorate, by release the parasitoid Cirrospilus
quadristriatus with two rate 8 and 12 parasitoid individuals per
replicate. Twenty newly emerged leaves were randomly picked up
weekly from each replicate. Larvae, pupae and calculate the
infestation rate. Percentage of parasitism was recorded by exam 50
stage ofF. citrella (larvae and pupae).
2.1. Study the infestation rate:
The above mentioned results on the efficacy of release parasitoid
C. quadristriatus with two rate 8, 12parasitoid individuals and control
(without release) revealed that, the differences between treatments
were low significant. The annual average of infestation rate with p.
citrella in both release 8 and 12 parasitoids recorded 68.68% and
68.80%, respectively, but in control it was 74.2%. So, the differences
in infestation rate between treatments was simple because the shoots
of sour orange in treatments were preferable and susceptible to attack
Summary and Conclusion
114
Summary and Conclusion
with more insect adults females of p. citrella which may deposit their
eggs on the leaves of treatments by flying moths.
2.2. Larvae and pupae population:
Weekly samples were picked up form each treatments to record
the number of larvae and pupae, there was low difference in numbers
of eLM oflarvae and pupae between 8 & 12 released parasitoid and
control. The annual average of number of p. citrella in 8 and 12
parasitoids and control (without release) was 28.29, 26.75 and 30.53
stage ofP. citrella, respectively.
2.3. The percentage of parasitism:
The obtained results showed highly significant and positively
differences in the percentage of parasitism of P. citrella between
treatments. In the case of release 8 parasitoids the % of parasitism
increased to (20.6%) parasitism after one week of release and the
highest percentage of parasitism was 35.3% recorded at October 23”’.
But in the rate of 12 parasitoids was percentage of parasitism 24.6%
after one week of release. After six weeks at October 23rd , the
percentage of parasitism was 57.3%, however, after seven weeks of
release it become 61.3% at the end of October. The highest percentage
of parasitism reached 70% at November 13 th. But in control the role of
natural enemies was lower during the same period, the highest
percentage of parasitism 30% at the same date(13 th November). The
annual average for 8 and 12 parasitoids and control (without release)
was 23.57%, 41.40% and 14.05% percentage of parasitism,
respectively. So, the above mentioned results revealed that the release
of 12 parasitoid individuals gave the best results of percentage of
parasitism.
3. Agricultural control:
This course of investigation was carried out during two
successive years 2002-2003 and 2003-2004 by using two kinds of
fertilization, nitrogen (N) and potassium (K). Weekly sample (20
leaves) were picked up from each replicate of Navel orange orchard
in Qalubia Governorate, to explore the effect of different levels of
fertilization, in reducing the infestation and larvae & pupae population
ofCLM.
3.1. The first season:
This experiment was carried out during 2002-2003 to evaluate
the effect of nitrogen and potassium fertilization.
3.1.1. The infestation rate:
The results showed that nitrogen fertilization led to produce
more shoots and terminal leaves which concerned with highly
attraction for citrus leaf miner. But the using of potassium fertilization
led to tissue toughness and may be, sometimes, limits citrus leaf miner
mobility and feeding.
3.1.2. The total number larvae and pupae:
Also, the using of nitrogen led to more number of larvae and
pupae which was infested leaves of citrus Navel orange, but using
potassium fertilization led to the decrease the number of larvae and
pupae. So it can be recommended not used high level of nitrogen
fertilization during summer and autumn season, because it using led to
high number of larvae and pupae, also increase the infestation rate.
Also, it can be recommended to use the second level of potassium
fertilization (100 kg/fed.) depending on lowest of number larvae with
pupae and infestation rate.
Summary and Conclusion
3.2. The second season:
3.2.1. The infestation rate:
Statistical analysis showed highly significantly difference
between the treatment with recommended dose of nitrogen with
double recommended dose of potassium fertilization (500 kg nitrogen
+ 400 kg potassium per feddan) which showed highly level of
infestation and double of recommended dose of nitrogen with
recommended of potassium fertilization (1000 kg nitrogen + 200 kg
potassium/fed.) which caused lower level of infestation with P.
citrella.
3.2.2. The total number of larvae and pupae:
The obtained results indicated that the population of citrus leaf
miner larvae and pupae occurred in non significant difference under
the treatment of fertilization.
4. Natural control:
This course of investigation was carried out during two
successive years 2002-2003 and 2003-2004 in two citrus orchards one
treated with insecticides and another was untreated to explore the role
of natural enemies in reducing the population of the citrus leaf miner.
4.1. The first year:
4.1.1. Study of percentage of parasitism:The obtained results during the first year in the treated orchards
indicated that the high % of parasitism either in treated orchard or
untreated was recorded during the period form the mid. Of July to the
mid. of October where it was 28% and 36% in treated and untreated
respectively with insecticides and another the untreated one indicated
that the high percentage was recorded during the period form mid-July
and the mid-October. So it can be seen there was obvious effect in the
Sunnnaryand Conclusion
reducing percentage of parasitism to P ·t ll d . CI re a ue to the use of
insecticides in the treated orchard.
4.1.2. The predation rate:
The highest two peaks of predation rate was recorded during the
mid-July and the end of October in the treated orchard with insecticides
recording 34% and 38% predation rate, respectively. But in the untreated
orchard the highest predation rate was occurred at the end of June and
the end of September showing 52% and 64%, respectively. It can
conclude that the role of predators untreated orchard with insecticides
was the higher than in the treated one. Also, the percentage of predation
was high than the percentage of parasitism.
4.2. The second year:
4.2.1. The percentage of parasitism:
The percentage of parasitism showed in a treated orchard was
recorded two peaks occurred during the mid-July and the end of
September with 34% and 24% percentage of parasitism, respectively.
While an untreated orchard it was occurred during the mid-July and
the mid-October recording 36% and 52%, respectively. So, it can be
said that the role of parasitoids was higher in an untreated orchard
than in that treated orchard because the use of insecticides decreases
the number of parasitoids.
4.2.2. The predation rate:
The role of predators in- a treated orchard appeared in two peaks
of predation in the mid. of July and at the end of October which was
46% and 32% pre daatnion rate, respectiv.e lyv.Buutt Iit was in untreated
orchard in the mid. of July and in the mid. of September recording
50% predation in two peaks. So it can be said that there was visible
role predators in untreated orchard with insecticides higher than the
treated orchard.
Summary and Conclusion
5. Mechanical control:
5.1. Study the effect of pruning:
The first season was occurred from January 2002 to January
2003. Five peaks of infestation rate were recorded in both oppress
pruning and moderately pruning. The highest peak in oppress pruning
was recorded during the period from the 21 st to 13 th September,
showing 100% infestation. While the highest peak of infestation in
moderately pruning was occurred from the end of June to the end of
the second week of September which it was about 100% infestation.
generally the infestation rate was high in the case of oppress pruning
than it in moderately pruning because the oppress pruning in citrus
trees led to produce high number of shoots and terminal leaves which
was highly susceptible (the most preferred) to citrus leaf miner P.
citrella in summer and autumn seasons. As for the mean number of
larvae and pupae of citrus leaf miner during the same year it recorded
six peaks in the oppress pruning the highest one was recorded in the
beginning of the third week of September recording 36.3 individual
/20 leaves (sample). While, in the moderately pruning only five peaks
recorded during the same period, and the highest one was 34
individuaV20 leaves at the end of the second week of September.
5.1.2. The second season:
This experiment of investigation was carried out during 2003-
2004 in navel orange orchard in Qalubia Governorate. Also six peaks
appeared in oppress pruning, but the highest one was occurred at the
end of the second week of June (about 96.6%/20 leaves). While in the
trees appeased to moderately pruning six peaks, of infestation rate
were recorded with highest one at the second week of July (about
56.6% infestation/20 leaves). Also, the total number of larvae and
pupae go in the same trend from the side of peaks number and the
time of appearance (five peaks and the highest was the end of the
second week of June) (about 30.2 stage/20 leaves). While, it was
recorded in moderately pruning the number of larvae and pupae peaks
Summary and Conclusion
were about five peak, with the highest number of larvae and pupae
appeased at the second week of July (14.3 stage/20 leaves). So, it may
conclude that the oppress pruning led to produce more newly emerged
shoots and terminal leaves which it was highly susceptible to infested
by citrus leaf miner, and subsequently increase in high level of
infestation and numbers of larvae and pupae.
5.2. Effect of light:
This experiment was carried out during one year from April
2003 to April 2004 on the newly, grown sour orange seedlings. The
obtained data showed four peaks of infestation rate in the under light
seedlings, and the highest peak appeared at the end of the third week
of September (48.3% /20 leaves). Also, in the treatment without light
seedlings five peaks were recorded, with the highest peaks at the end
of the third week of September. As for the total numbers of larvae
and pupae four peaks were registrated in under light seedlings, and
the highest numbers appeared at the end of the third week of
September (9.6 stage/20 leaves). While, in without light, seedlings
treatments six peaks were recorded, with the highest peak (7.6
stage/20 leaves), during the end of the third week of September. So it
can be said the infestation rate and total number of larvae and pupae
were high in the without light seedlings than the under light seedlings,
also the infestation rate started early in without light treatment than in
the under light seedlings.
6.Trial of using IPM program:
Evaluation of each control agents separately, it was aerial to use
group of these agents in integrated program, depending on the efficacy
of factors on the citrus leaf miner. So, the IPM program comprised
chemical control by using Vertimec 25 cm’ + 250 cm’ KZ oil per 100
Liters water and biological control by release parasitoids of C.
quadristriatus after the end of the residual effect of using chemical
Summary and Conclusion
Summary and Conclusion
control. This experiment was carried out during the period from the
23rl June to the 15 th September. Results obtained showed highly
significantly difference in infestation rate and number of larvae and
pupae between IMP program treatment and control. Also, this
program may be used twice during the season depending on the
population of P. citronella.
This investigation was conducted in Qalubia Governorate,
during two successive seasons 2002-2003 and 2003-2004. Results
obtained may be concluded in the followings:
1- The infestation rate of P. citrella appeared during the period
from the mid-May to the first of December in old trees, also the high
level of population ofp . citrella was i.n summer and autumn seasons
but in spring the citrus orchard never infested with citrus leaf
miner(75% of total shoots in all the year). Only the newly shoots and
terminal leaves in summer and autumn (25% of total shoots in all the
year) harbored the highest level of infestation rate of P. citrella.
2- The application ofVertimec 1.8% (Abamectin) + KZ oil with
two concentrations recommended 25 erne Vertimec + 250 em- KZ
oil/l 00 L. water and half concentration achieved good results.
3- The release of the parasitoid C. quadristriatus gave good
results, but the release must be repeated every six weeks to keep the
balance between the pest and the parasitoid.
4- Potassium fertilization led to tissue toughness and limit
mobility and feeding the citrus leaf miner, but the nitrogen
fertilization led to increase numbers of newly shoots and leaves which
was highly susceptible in summer and autumn seasons.
5- The oppress pruning led to the tree produce more shoots in
summer and autumn. So this shoots was highly infested with eLM.
Hence it can be recommended that must be avoid the oppress pruning
in old trees.
6-A trial of preparing IPM program gave promising trend to
reduce the infestation rate with citrus leaf miner and at the same time
led to decrease in the chemical control and subsequently minimize the
environmental pollution.