الفهرس 
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Abstract
SUMMARY
Root rots diseases are widespread in the world and considered as a
major constraint to bean production. It’s caused by R. solani, F. solani
and M. phaseolina. It is an important soilborne pathogenic fungus causes
severe damage to many economically important crops and plants.
Chaetomium species have potential to be biological control agents
suppress growth pathogens through mycoparasitism and antibiosis.
This study was initiated to evaluate the potential Chaetomium spp.
on management of bean damping-off.
The results of the present study could be summarized as follows:
1. Six isolates of bean root rot pathogen were obtained from Giza and
Qalyubiya governorate. Pathogenicity of5isolates of bean root rot
pathogens was carried out onbean plant (Giza 6). All isolates were
pathogenic to bean with different degrees. R. solani1isolated from
Qalyubiya was the most pathogenic one followed by M. phaseolina
isolated from Giza. The least virulence isolate was F. solani2 isolated
from Giza. In case of post-emergence damping-off, it was found that
M. phaseolina gave the highest percentage of infection followed by R.
solani1.
2. Nineteen isolates of Chaetomium were isolated from different plants
sources i.e. broccoli, potato, citrus, pepper, strawberry, drasena,
tomato, barley and straw. Also, fourteen isolates of Chaetomium spp.
were kindlyobtained from Mycology Research & Diseases Survey
Department, Plant Pathology Research Institute,(ARC).
3. Chaetomium species were identified by morphological characterssuch
as color of the cultures, type of terminal hair and lateral hairs,
structural characters of the perithecia, asci, and ascospores, and
isolates were identified as:- C. globosum, C. bostrychodes,
118
SUMMARY
Huda Z.A. Zoher (2017), Ph.D. Thesis, Fac. of Agirc.,Ain Shams Univ.
C.madrasense,C. brasiliense, C. atrobrunneum, C. nigricolor and C.
megalocarpum.
4. DNA sequencingwas used in order to study the similarity between
Chaetomium speices.The phylogenetic analysis of 18 isolates of
Chaetomium spp. conducted by using ITS 4, ITS6 region were
compared with 21 isolates of Chaetomium spp. from GenBank. The
majority of Chaetomium species in this study was seven species
groups, C. globosum, C. bostrychodes, C.madrasense,C. brasiliense,
C. atrobrunneum, C. nigricolor and C. megalocarpum. there are high
genetic similarity among different isolates of Chaetomium spp.
obtained from different sources,C. madrasense and C. megalocarpum
showed 99.4% similarity, and these two speciesshowed 95.9%
similarity with C. globosum formed a separate group within cluster I,
separating out at a bootstrap of C. bostrychodes.
5. Thirty three isolates of Chaetomium spp. were evaluated for
theirpotentiality on bean seed germination. Some isolates of
Chaetomium spp. were found effective to enhance the germination of
bean seeds. C. globosum1, C. globosum2 and C. madrasense gave the
highest effect on seedling. Meanwhile the least effect was shown with
C. nigricolor1.
6. Effectof 33 different isolates of Chaetomium spp. on suppressing
mycelial growth of root rot bean pathogens indicated that, all isolates
of Chaetomium spp. suppressed the radial growth of pathogens.The
mode of action of Chaetomium spp. was varied. Some isolates gave
inhibition zoon and some others showed mycoparasitism. C.
globosum11 was the most effective one for inhibiting mycelial growth
of the different pathogens followed by C. megalocarpum while, C.
atrobrunneum4gave the least reduction for mycelial growth.
7. The potentiality of mycelial growth of pathogenic fungi in the areas of
competition was studied to determine their pathogenicity. All isolates
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SUMMARY
Huda Z.A. Zoher (2017), Ph.D. Thesis, Fac. of Agirc.,Ain Shams Univ.
of Chaetomium spp. reduced the incidence of seedling diseases
companied with control pathogen without Chaetomium spp. It was
found that mycelia of pathogens lost its aggressiveness as root rot of
bean in comparison to control. C. globosum1gave the highest effect to
reduced bean seedling diseases incidence followed by C. madrasesne
and C. nigricolor. Meanwhile C. bostrychodes and C. brasiliense
were gave the least effect on seedling diseases incidence.
8. Slide technique was used to study the interaction between
Chaetomium spp. and root rot pathogens.Microscopic examinations
of antagonistic areas between bioagent and bean pathogenic fungi
were conducted using light microscope. It was found that Chaetomium
spp. densely coiled around the hypha of root- rot pathogensand host
hyphae became empty from cytoplasm distorted host mycelium.
9. Examined re-isolated from soil infested with C.globosum1 and root
rot pathogens showed lysis of mycelium due to over growth and
penetration through hyphal pegs and coiling produced by antagonists.
10. Electron microscope used to examin ultrathin sections from the
interaction region between C. globosum1 and R. solani observation
there are demolition in mycelium R. solani and cytoplasm and
protoplast membrane in some hyphal cells was break down.
11. Effect of culture filtrates of Chaetomium spp. inducted that, all
isolates of Chaetomium caused significant reduction of mycelia dry
weight of the tested pathogens. C. globosum11gave the highest
decreased dry weightof R. solani mycelia. While C. globosum1and
10showed the best effect on decreased dry weight of M. phaseolina
mycelia. C. atrobrunneum4was not effective on mycelial dry weight
for R. solani and M. phaseolina.
12. The interaction betweenpartially purified culture filtrates of some
isolates of Chaetomium spp. by ethyl acetate and root rot pathogens
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SUMMARY
Huda Z.A. Zoher (2017), Ph.D. Thesis, Fac. of Agirc.,Ain Shams Univ.
reveled that, there are varied between different bioagents in their
effect on root rot pathogens, according to the isolate.Antagonistic
areas illustratedthe presence of weak mycelial growth of the
pathogens. C. globosum 1 was the most effective bioagent for
inhibiting mycelial growth of R. solani and M. phaseolina. Meanwhile
C. brasiliense 1 gave the least reduction for mycelial growth of root
rot pathogens.
13. Examination of light microscope showed the effect of partially
purified culture filtrate on mycelium root rot pathogens and distort in
cell wall of mycelium pathogen.
14. The effect of malformed myceliumof pathogens affected with partially
purified culture filtrates of Chaetomium spp. on bean seedsinfection
less thanmyceliumof pathogenic fungi that were not treated. Result
indicated that culture filtrates of Chaetomium spp. were affect on M.
phaseolina more than R. solani. It was clear that Chaetomiun spp.
could be able less aggressive fungal pathogen.
15. Study the chitinase activity exhibited by 33 isolates of Chaetomium
was grown in Chitin medium supplemented with dye indicator
bromocresol purple. Showed that almost all isolates could be analysis
chitin in medium. While C. globosum5,10 and12 and C.madrasense2,
6had not ability to breakdown of chitin into N-acetylglucosamine
while it were grown on medium and formation perithecia without
change the color media.
16. Determined of β-glucanase and chitinases activities were assayed by
measuring the amount of reducing sugars released.There are variation
between different isolates of Chaetomium in the activity of Glucanase
and Chitinase in culture filtrate and its biomass. Biomass from M.
phaseolina as a carbon source for the induction of β-glucanases and
chitinases was used.C. madrasense 5 gave the highest activity of β-
glucanases in biomass but C. globosum1gave the highest activity in
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SUMMARY
Huda Z.A. Zoher (2017), Ph.D. Thesis, Fac. of Agirc.,Ain Shams Univ.
culture filtrate and also gave the highest activity of chitinases in
culture filtrate and its biomass. While C. atrobrunneum3 gave the
least activity of chitinase in culture filtrate and biomass.
17. The ability of Chaetomium spp. to produce β-glucanases and
chitinasein presence of pathogen was studied. Chaetomium spp.
isolates were grown on PDB then R. solani was inoculation after 3
days from inocubation Chaetomium. It was found β-glucanases and
chitinase are produce during the interaction between different isolates
of Chaetomium spp. and R. solani as a host. There are no significant
differences between all isolates in their activity. C. globosum1 gave
the highest activity in producing enzyme in culture filtrate and
biomass.
18. Partially purified cultural filtrate of three isolates of C. globosum1,2
and 7were investigated by gas chromatography-mass spectrometry
(GC/MS).The main constituents of the extractofC. globosum1 was
propionic acid, 1-Octadecene , Benzenedicarboxylic acid, Phosphonic
acid, gluconic acid which considered as antifungal compounds. Also
1H-Indole-3-acetic acid was considered as plant hormone. C.
globosum2, was produced some chemical compounds i.e1-Octadecen,
Mannonic acid, 1-Hexadecene, 1,2-Benzisothiazole,Succinic acid and
Succinic acid as anti-fungal activity.C. globosum7 also constituents of
Propanoic acid, 1,2Benzenedicarboxylic acid, Octadecanoic acid, DGlucopyranose,
1H-Indole-2-carboxylic acid, benzoic acid,
Hexadecanoic acid, which considered as anti-fungal activity. Data
indicated that three different isolates of C. globosum gave the same
compounds such as 1,2Benzenedicarboxylic acid, Octadiene1,
Hexadecene and Propionic acid which have antifungal activity.
19. Five different isolates of Chaetomium spp. were tested for their
capability to control root rot pathogens. Application of different
biocontrol agents completely suppressed post-emergence damping122
SUMMARY
Huda Z.A. Zoher (2017), Ph.D. Thesis, Fac. of Agirc.,Ain Shams Univ.
off.C. globosum1 was more effective in controlling the pre-emergence
damping-off disease while,C. madrasense5 gave the least effective in
controlling pre-emergence damping-off.The effect of different isolates
of Chaetomim spp. as biocontrol agents on dry weight of bean plants
reveled that,C. globosum1 was the best bioagent affected on shoot and
root dry weight, followed by C. globosum2. C.atrobrunneum3, C.
globosum8 and C. madrasense5 the increase was significant
comparing with control.
20. Differenttype of compost and straw were used with C. globosum1 as a
bioagent on root rot pathogens reduced disease incidence.Compost A
and straw gave the best reduction in root rot bean diseases, the effect
of C. globosum as a biocontrol agent on M. phaseolina was more
effective than their effect on R. solani .Compost A with C. globosum1
gave the best effect on dry weight of shoot and root of bean plants.
Generally, results from this study demonstrated that Chaetomium
spp. potentially for controlling bean root rot pathogen. Also increased
shoot and root of bean plants. There are highly similarity between
Chaetomium speices on morphological and molecular characterization.
Also some antifungal compound produced.