This research was conducted in laboratory of Nematology in the Center of Scientific
Agricultural Research in Lattakia, to detection of Entomopathogenic Nematodes (EPNs) in
Citrus Orchards soils in Lattakia governorate.
A total of 66 composite soil
samples were collected from Citrus orchards during (2016-
2017). Entomopathogenic nematodes (EPNs) were recovered from soil samples by the
insect baiting technique, using seventh instar larvae of the Greater wax moth Galleria
mellonella (Lepidoptera: Pyralidae). Infective juveniles (IJs) were collected from G.
mellonella cadavers using the method of White (1927).
EPN isolates were identified based on morphometric methods. Eight isolates were
identified as Heterorhabditis bacteriophora Poinar 1976 (Ord. Rhabditida: Fam.
Heterorhabditidae) .
Positive soil samples ratio was 12.12% of total samples, where EPNs isolates were
extracted from regions (Al-Bassa, Al-Magreet, Al-Shamia, Gio, Al-Kharnoba, Al-Sorsokia,
Fideo, Borj Al-Qasab)0 The soil textures of the EPNs positive samples were (sandy loam,
silt loam, loamy sand, loamy clay sand, clay) with ( pH 6.34- :0.5) and (1.99- 4.82) g\100g
organic content. The electrical conductivity of the nematode positive soils varied from 0.33
to 0.82 ds/m.
The experiment was conducted during the two seasons (2015 , 2016 ) on the Lemon trees
cv (Meyer ) aiming at studying the effect of the foliar spraying with the nutrients ( boron ,
zinc and iron ) on physical and chemical properties of the fruits Th
ese nutrients were
sprayed separately or as a mixture .
The average of each of the physical properties of the fruit (length , width , firmness,
volume and weight of the fruit ) , in addition to rind thickness and the fruits ` juice volume,
,the chemical properties of the fruit juice (total soluble solids, total sugars, total acidity,
vitamin C) were studied. An increase was observed in all the studied parameters in the
sprayed treatments compared to the control from( 6.37%- 3.33% -0.37% -
34.57mg%)to(9.33% -4.88% -1.89% -43.5%) in the first season and( 9.75% 5.87- 3.32% -
45%) in the second season, respectively. As a result of the statistical analysis, there were
significant differences between all the studied treatments and the control with overpass of
the treatment of the three elements (iron chelate + boron oxide + zinc chelate ) of all
treatments in the most of the studied figures in both seasons. Statistical analysis of the fruit
rind thickness showed the absence of the significant differences among the studied
treatments.
The study was carried out on trifoliate orange rootstock trees (Poncirus trifoliata L.)
at Ciano Research Station where the trees were sprayed with nutrients or gibberelic acid
GA3 or togethers, beside the control (without spraying). Different trea
tments of seed
storage were tested in order to study their effect on seed viability to increase it. The seeds
were stored for three months using four treatments: (a) seed storage in fruits at +4˚C, (b)
Storage in juice at +4˚C, (c) Storage at lab temperature, and (d) seed storage at fridge
temperature +4˚C. The results showed that all spraying treatments were positive at
postharvest, as compared with the control. However, treatment of seed storage inside the
fruit gave the highest significant germination rate for all spraying treatments. Treatments
of spraying with nutrients were the best. The viability of seeds considerably decreased for
all treatments of seed storage at fridge temperature +4˚C, whereas germination was zero for
seed stored in juice and seed stored at lab temperature.
This research carried out in the orchards of the Stamo area province of Lattakia citrus
during the years 2014-2015, and the results of the study showed that the insect black
cortical one generation per year with a second partial generation during t
he summer. Under
the insect overwintering nymph stage in the second age is the most able to withstand the
low-temperature phase in the winter. Mermaid back age-second activity in the beginning of
spring to complete their life cycle where the female young appear in early April on each of
the branches and leaves, to show adult females with the beginning of the month of May
and starts the eggs to hatch in the middle of this month and will continue until the month of
July. The study found that the nymph stage second phase age is the most common during
the season at each of the branches and leaves. Observed the death of large numbers of the
insect in the phasic nymph third age and female fledgling stage, which evolved during the
same season, as the study of the distribution and the spread of the different phases of the
insect on the plant parts showed that the branches were more injury than securities with
higher than moral in the population density of the presence of eccentric nymph and adult
stages the branches compared with the leaves.
A laboratory study was conducted on the parasitoid Citrostichus phyllocnistoides
Narayanan (Eulophidae : Hymenoptera)under average of temperature (18.12± 2.12 Cº)
with Temperature range from 15-23Cº. The final results oflaboratory study indicated t
hat
parasitoid was passed four stages to complete life cycle. The average development time
was: 3.7±0.9 days for eggs – 7.8±0.9 days for larvae,(the time required from the eggs to
hatch and continued untilthelarvae enter the pupal stage 6-10 days) , and12.7±1.03 days for
pupa (the time required from the beginning of pupation to emergence of adult 11-14 days).
The parasitoid needs in average23.3±2.7 days to complete its life cycle. Male longevity
3.8±0.8 days , and female 4.2±0.9 days.
The experiment was done within -2014 in plant physiology lab.of agriculture faculty
of Tishreen University for estimation of high temperature stress toleration of citrus leaves
in three varietis(Citrus Unshiu , Meyer Lemon,Citrus SinensisWashington
). Many random
samples of leaves were gathered from the foliage of the examined categories whereas tha
average of the taken leaves was 200 from the whole sides for each one tree from the
branches which are one year old . which were put for limited duration in a water bath about
many different degrees of temperature then they were put in water and then in a solution of
HCL acid .
Many references were studied of containing :non spotting on leaves ,which means
they are un harmed,simple spotting,the spotting of more than half of the leaves area,the
perfect leaves spotting.
Studied temperature were as the following :40-50-60-70-80.Each one of this
mentiond temperature,40 leaves were used .The statistics analys were done with the way of
Genstat 12,for the comparison between averages for the sake of calculating the least
significant difference at the guidance level :5% .
Studies showed that Satsuma leaves are the most toleration for high temperature,next
Citrus SinensisWashington is less than Satsuma.At last Meyer Lemon was the least .
Effect of Citrus trestiza virus (CTV) in Growth of Balady common orange and
Satsuma trees grafted on sour orange Rootstock in Hraisoon during 2013 was studied. The
results showed that of infection by CTV caused deformation of shaped leaves, boat or
spoon-shaped leaves. The symptoms was greater in Satsuma from Balady common orange
trees. Also leaf size average of Balady common orange trees reduced from 15.58 cm2 in
healthy trees to 11.82 cm2 in infection trees as percentage 24.13, and from 19.64 cm2 in
healthy Satsuma trees to 12.38 cm2 in infection trees as percentage 36.97. and length
average of spring, summery and autumnal fresh foliages growths was reduced from 20.98
cm, 14.62 cm, 12.17cm in healthy Balady common orange trees to18.75cm, 12.52cm, 9.32
cm in infection trees respectively. Also it reduced from 18.78 cm, 14.56 cm, 10.06 cm in
healthy Satsuma trees to 13.78 cm, 9.34 cm, 6.03 cm in infection trees respectively, the
CTV had no significant effect on Trunk circumference in both varieties.
The research aims to Identify some species of aphids on plant families, and test the
possibility of transfer to the local isolate of Cucumber mosaic virus. Two species of aphids
in bean fields and citrus orchards have been defined, namely: Black be
an aphid Aphis
fabae and Cotton aphid Aphis gossypii, respectively, depending on the specialized
classification keys. The infection proved vital feedback and testing the function using
plants: Nicotiana tabacum and Chenopodium quinoa transfer each of the A. fabae and A.
gossypii local isolate of Cucumber mosaic virus.
The effect of some essential oils taken from Cinnamomum zeylanicum, Citrus
limonum and Rosmarinus Officinalis was investigated in relation to the growth of bacteria
Paenibacillus larvae which causes American Foulbrood disease that affects world hon
ey
bees Apis mellifera L. The study was carried out in the laboratories of the Faculty of
Agriculture, Damascus University from 2012 till 2013. This is in order to contribute to
preparing an integrated pest management program for American Foulbrood disease. The
oils were extracted from the plants using steam distillation. The effects of the
concentrations of oils on the growth of P. larvae were tested between (3.90625 - 500
μg/ml) using agar disc diffusion in petri plates. Results showed that the essential oils used
stop the growth of P. larvae in some of their concentrations. The minimal inhibitory
concentrations which stop the growth of P. larvae of the oils of Cinnamomum zeylanicum,
Citrus limonum and Rosmarinus officinalis were recorded at 31.25 μg/ml, 62.5 μg/ml, 125
μg/ml respectively.
Effect of different degrees of temperature, different levels of pH , different periods of
light and four media (PDA, OMA, MEA, CzA) was studied in vitro against the growth of
C. gloeosporioides causing anthracnose disease of citrus fruits. The resu
lts indicated that
the growth of fungus was maximum at temperature 30°C and at pH = (5.5,6,6.5), and Light
was unnecessary for the growth of C. gloeosporioides. Among the different media tested
PDA and OMA supported the maximum growth of fungus.
