الفهرس 
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Abstract
Tomato (Lycopersicon esculentum Mill.) is one of the most important economical crops, which belong to family Solanaceae. Tomato cultivated for its fruits of economic importance and
nutritional value and high tomato plants important in domestic
consumption , export and food industries. Bacterial spot of tomato
caused by Xanthomonas campestris pv. vesicatoria (Doidge) Dye
(Xvv) is present wherever tomato and peppers are grown. In general,
Xanthomonas pathovars have narrow host ranges.
The obtained results of the present study could be
summarized as follows:
1. Sum of 60 bacterial isolates were obtained from naturally infected
tomato collected from naturally infected tomato leaves and seeds in four
locations i.e. El-Doki (Super Marmand, cv), Qaha (Peto 86 cv and super
strain B cv), Fac. of Agriculture Ain Shams -Kalubia Governorate
(Money maker, Super Marmand and Super strain B cv) and Rashid
(Mors44, Niagra) Domiata Governorate. The isolated bacteria belong to 4
genera and 4 species.
2. Xanthomonas vesicatoria was the more occurred (30 trials of
frequency) in all tested samples comparing to the other isolated
bacteria. The highest isolation number and frequency% of X.
vesicatoria was recorded in Fac. of agriculture Ain Shams (63.6%)
followed by EL-Doki (50%) and Qaha location (35.7%), meanwhile,
the least frequency (29.4%) of X. vesicatoria was recorded in Rashid
location. Other bacteria were isolated and Rashid location showed the
highest number and frequency % (58.8%) followed by Fac. of
agriculture Ain Shams location (36.4%). 3. Sixteen of cultivars and hybrids were used for the isolation of
pathogenic bacteria that caused spots on tomato plants. All tested
cultivars, Dora, Gs12, KTM 141, Niagra, Diamante F1, Hypride7796,
Super strain B hybrids, Mors44, VT916G.SI Hypride, HMX4791
Hypride and faqlta 38 gave negative reaction when direct planting on
the Nutrient agar (NA). Meanwhile, Super strain B was the only
resulted positive reaction for X. vesicatoria isolated. On the other
hand, all used seeds of cultivars and hybrids of tomato were showed
gave negative reaction for Pseudomonas isolation. Meanwhile, other
bacteria that isolated from tomato seeds of cvs and hybrids were
different according the cvs, hence seeds of Super strain B, Gs12 and
faqlta 38 were the only results for other bacteria isolated.
4. According the morphological, physiological and biochemical
characteristics, out of 60 bacterial isolates which isolated from
tomato seeds, leaves, stems and fruits, 30 isolates were identified as
Xanthomonas, 10 identified to each Bacillus and Pseudomonas.
Other lasted of 10 isolates were identified as non-pathogenic bacteria.
5. Regarding of pathogenicity test, 30 isolates of bacteria that
isolated from bacterial spot of tomato was tested for their ability to
infect of tomato and pepper plants. Twelve isolates of Xanthomonas
vesicatoria, numbers: Xv2, Xv3, Xv7, Xv8, Xv10, Xv13, Xv14, Xv20,
Xv22, Xv23, Xv26 and Xv28 were the highly pathogenic and caused
bacterial spot on tomato (leaves) and pepper (leaves), meanwhile,
eight isolates of X. vesicatoria (No. Xv1, Xv 4, Xv5, Xv9, Xv11, Xv12,
Xv15 and Xv24) were resulted the moderated pathogenic effect by
showing a few symptoms of leaves spot on tomato and pepper plants.
The last of the ten isolates of X. vesicatoria (No. X6, X16, X17, X18, X19, X21, X25, X27, X29and X30) were non-pathogenic and no
symptoms was showed on tomato and pepper leaves after their tested.
6. Concerning the host range, three isolates of Xanthomonas
vesicatoria that caused bacterial spot of tomato, No. Xv28 was highly
pathogenic in Qaha, Xv22 which was highly pathogenic in Rashid and
Xv10 that highly pathogenic in El-Doki, were used to study of their
ability to infect of different hosts. Data indicated that, the three isolated
were highly pathogenic and caused bacterial spot on tomato plants,
meanwhile, the remained isolates were moderate pathogenic and
showed little symptoms on tomato leaves when tested for their
pathogenicity. All these tested isolates were highly pathogenic on
tomato and pepper and never affected potato and cabbage, common
bean, eggplant, lettuce, beans, strawberry and cantaloupe. On the
other hand, the three isolates showed moderately effect on datura
plants.
7. Different bactericides, antibiotics, oils and plant extracts,
inducing resistance, bio-agents were used at different concentrations
to study there effect on the growth of pathogenic bacteria
Xanthomonas vesicatoria isolates (as inhibition zone cm) under in
vitro conditions. As for the bactericides, Galbin-Cu48% and Copper
oxychloride 54% had inhibitory effect on growth of the pathogenic
bacteria compared with the control. Also, this inhibition was
increased according to the increase of concentrations of bactericides.
On the other hand, the different isolates of X. vesicatoria (Xv28, Xv22
and Xv10) were varied for their sensitivity to these bactericides. In this respect, Copper oxychloride was more effective than Galbin-cu for
the reduction in growth of all isolates.
8. Two antibiotics Erythromycin and Tetracycline were tested at
different concentrations for their effect on the growth Xanthomonas
vesicatoria isolates. All tested antibiotics had inhibitory effect on
growth of the pathogenic bacteria compared with the control. This
inhibition zone was increased with the increase of rates of antibiotics.
Also, different isolates of Xanthomonas vesicatoria were varied in
tolerance of these antibiotics. In this respect, Tetracycline was more
effective than Erythromycin for the increasing of zone inhibition for
the three isolates of Xanthomonas. Meanwhile, Erythromycin caused
moderately effective to reduce the growth on the three isolates of
Xv28, Xv22 and Xv10, respectively.
9. Concentrations of the plant extract of garlic (Allium sativum)
had inhibitory effect on growth of the pathogenic bacteria compared
with the control. This inhibition was increased accorded with
increasing of rates of plant extract. On the other hand, isolates of
Xanthomonas were varied for the effect of plant extract.
10. Different concentrations of two different plant oil, mentha oil
(Mentha aquatica) and clove oil (Syzygium aromaticum) were tested
on growth Xanthomonas vesicatoria. The two different plant oils had
inhibitory effect on growth of the pathogenic bacteria compared with
the control. This inhibition was increased with the increasing rates of
plant oil. On the other hand, the three different isolates of
Xanthomonas vesicatoria were varied for their sensitivity different
plant oils.
11. Acids ascorbic acid and salicylic acid had inhibitory effect on
growth of the pathogenic bacteria when compared to the control
treatment. The inhibition zone was increased with increasing the rates of acids. Also, ascorbic acid more effective, (2.77 cm as means of
inhibition zone), than salicylic acid (1.38 cm) for inhibition zone the
three isolates of Xanthomonas. Also, ascorbic acid, was highest
effective on the reduce the growth of all isolates, where, it caused 3.5
cm zone inhibition, 2.6 and 3.1 cm of zone inhibition for
Xanthomonas vesicatoria-10,-28and-22, respectively. Meanwhile,
3.4cm, 2.5 and 2.0 cm of inhibition zone were obtained from salicylic
acid on Xanthomonas vesicatoria-10&X.v-28 and X.v-22 respectively.
12. Kombucha was known as metabolic of different
microorganisms such as yeasts, fungi and bacteria on tea. Also, it has
inhibition effect on different microorganisms as bacteria. In this
respect, it was used at different concentrations for testing of their
ability to inhibit growth of X. vesicatoria isolates, in vitro. Results
indicated that, inhibition zone of different isolates of Xanthomonas
were increasing according to the increase of kombucha
concentrations. On the other hand, Xanthomonas vesicatoria-10and
X.v-28 were more sensitive to kombucha and resulted 2.1 cm and 2.0
cm inhibition zone than X.v -22 gave only 1.8 cm inhibition zone.
13. Two isolates of antagonistic bacteria were tested for their
ability to inhibit growth of X. vesicatoria isolates, using King’s B
(KB) medium, in vitro. And indicated that tested Pseudomonas
fluorescense (i.e. Pf1), isolate were more effective against growth of
X. vesicatoria bacteria on King’s B medium, where inhibition zone
were 2.9cm,3.5cm and 4.1cm on isolates Xv28, Xv22andXv10,
respectively. Meanwhile, isolates of P. fluorescence (Pf2) was
moderately effective on KB medium against two pathogens, where inhibition zone were 3.1cm, 3.7cm ,4.5cm on isolates Xv28, Xv22and
Xv10, respectively.
14. Phages of Xanthomonas vesicatoria were isolated from
infected leaves of tomato and from tomato rhizosphere soil
samples,4- Phages of Xanthomonas vesicatoria were isolated from
infected leaves of tomato and from tomato rhizosphere soil samples,
using enrichment technique. These samples were collected from
Qalubia governorate. The phages were mostly isolated from infected
leaves of tomatoes and also from the rhizosphere soil of tomato
plants in the field. The phages produced different types of plaques.
The first type was the mostly frequent commercial, where the plaque
was circular with an irregular margin and the second type produced
circular plaques without determined margin.
15. Under greenhouse conditions, sixteen of tomato cultivars and
genotypes were evaluated to infection with three Xanthomonas
vesicatoria isolates under greenhouse conditions. Data revealed that,
Super strain B and Castle rock were highly susceptible to the
infection with Xanthomonas vesicatoria isolates. Meanwhile, Peto
86 and Gs12 were moderates susceptible to the infection. Money
maker and Dora were tolerant to the infections with Xanthomonas
vesicatoria isolate. On the other hand, the next ten of tomato cvs and
genotypes, i.e., Diamante F1, Hypride7796, Mors44, VT916G.SI,
HMX4791, Super strain B H, KTM 141, Niagra, Flora-Dade and
faqlta 38, showed resistant to infection with Xanthomonas
vesicatoria isolates
16. In conclusion, when comparing the effect of different
bactericides, oils and plant extracts, inducing resistances and bio agents for controlling the bacterial spot of tomato plants that caused
by three Xanthomonas vesicatoria isolates Xv28, Xv22 and Xv10
during 2009 and 2010 seasons. Results indicated that all treatments,
bactericides, oils and plant extracts, inducing resistances and bioagents,
were effective on controlling the disease on tomato plants
when compared with the control treatment. On the other hand,
bacteriocides was more effective in the diseases incedence, disease
severity, no. of spots/leaf and disease reduction % than other control
treatments, oils and plant extracts, inducing resistances and bioagents,
especially after 10 days from the infestation with Xv28. Also,
copper chloride, Galbin-cu and tetracycline were the most effective
than erythromycin. On the other hand, garlic (Allium sativum )
extracts was more effective on the diseases incedence, disease
severity, no. of spots/leaf and disease reduction % than mentha and
clove oils. Regarding the effect of the inducer resistance on tomato
plants after the infestation with Xanthomonas vesicatoria isolate
Xv28, ascorbic and acidic acids were more effective than biological
inducer (Kamboushe) in the diseases incedence, disease severity, no.
of spots/leaf and disease reduction %. On the other side,
Pseudomonas flurocences isolate No. 1 was more effective than
Pseudomonas flurocences isolate No. 2. for the diseases incedence,
disease severity, no. of spots/leaf and disease reduction % after 3 and
10 days from the infestation with Xv28, respectively.
17. Comparison between different bacteriophages for controlling
the infection of tomato plants after 3 and 10 days form infestation
with Xanthomonas vesicatoria isolate Xv28, Xv22, Xv10. Obtained
results indicated that, all treatments, i.e, phage 1, phage 2, phage 3, phage 4 and the mixed of different phage isolates (1+2+3+4) were
effective on controlling bacterial spot on tomato when compared
with the control treatment. Also, these treatments were effective in
the diseases indx, disease severity, mean of spots/20 leaf and disease
reduction % when compared with control treatment after 3 and 10
days from the infestation with Xanthomonas vesicatoria isolates
Xv28, Xv22, Xv10.
18. Effect of treated tomato seeds or seedling with hot water
under infestation of different isolates of Xanthomonas vesicatoria.
Tomato seeds or seedlings of cv Super strain B were infestated with
the three concentration of pathogenic bacteria and then treated with
hot water ( 48-50 0C/ 5 min) indirect way to study the effect on the
disease incidence. Results revealed that all water hot treatment were
effective for increasing survived plant compared with control
treatment. Data also showed that, positive relationship between the
inoculum increasing of Xanthomonas isolates and death of tomato
plants in the two cases (seeds and seedlings).
19. Concerning the relationship between using different
bactericides, oils and plant extracts, inducing resistances and bioagents
on controlling of bacterial spot diseases of tomato and some
biochemical changing treated plants (activity enzymes). All
treatments i.e., spraying with bactericides, oils and plant extracts,
inducing resistances and bio-agents, which sprayed on tomato plants
to control bacterial spot disease caused by Xanthomonas isolates
Xv28, Xv22, and Xv10, increased peroxidase and polyphenoloxidase
activity compared with control treatment The highest peroxidase activity was detected after seven and ten
days compared with three days from spraying in all the three
tested isolates of Xanthomonas.
20. Copper oxychloride caused the highest increased in
peroxidase and polyphenoloxidase through controlling bacterial spots
that caused by Xanthomonas isolates after three, seven and ten days,
respectively. Meanwhile, in general the least effect on the increasing
of peroxidase and polyphenoloxidase activity was recorded when
erythromycin was sprayed on tomato plants to control Xv28, Xv22 and
Xv10, respectively. On the other hand, galbin –cu was the highest
effective on increasing in peroxidase and polyphenoloxidase activity
compared with other bactericides treatments when it used for
controlling of Xv10.
21. According of the effect of using oils and plant extracts,
Allium sativum was the highest effect on increasing of peroxidase
and polyphenoloxidase activity through control of bacterial spot that
caused by Xanthomonas isolates. Also, clove oil was more effective
on the increasing of peroxideas and polyphenoloxidase when
compared by mentha oil when sprayed on tomato plants to control the
bacterial spot that caused by Xv28, Xv22 and Xv10, respectively.
Regarding of sprayed inducing resistances on tomato plants to control
bacterial spot that caused by Xv28, Xv22 and Xv10 caused increasing
of perioxidase and polyphenoloxidase activity. In this respect,
ascorbic and salicylic acid were more effective on increasing of
perioxidase and polyphenoloxidase activity than kambousha
treatment after the three, seven and ten days of inoculation of
bacterial spot disease Xv28, Xv22 and Xv10.