الفهرس 
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Abstract
Sesame (Sesamum indicum L.) plants at all their growth stages
were exposed to attacked by many phytopathogenic microorganisms
caused serious diseases. Root-rot and wilt diseases considered the most
destructive on sesame plants causing high amounts of losses in stand
plants, seed yield and seed oil content. Several studies about this subject
were carried out under the laboratory. greenhouse and field conditions.
The obtained results could be summarized as follow ;_
I-Several pathogenic fungi were isolated from naturalJy diseased plant
materials collected from seven localities, belonging to four.
Governorates of Egypt. i.e.Giza, El-Sharkia, EI-Bihiraand Beni-Suef,
Among isolated fungi, A1acrophomina phascoiina was the most
frequent and isolated from all localities (seven locations) followed by
R. solani and F ventricosum (three locations) and F. oxysporum; F
solani and S. rolfsii (two locations).
2- The isolated fungi were differed in their pathogenicities. ScleroJium
rolfsi! (isolate No.2) and M. phaseolina (isolate No.7) caused the
highest incidence of damping-off at seedling stage. while F
oxysporum (isolate No.2) caused the highest infection with root-rot
and wilt disease on standing plants. The latter two pathogenic isolates
were selected if 110totherwise was indicated for further laboratory and
greenhouse studies.
3- The double interaction between pairs of some pathogenic fungi grown
together on agar plates showed that the growth of F oxysporum was
surrounded by M phaseolin a or R. solani; but the latter two slightly
inhibited each other when placed together. Sclerotium rotfstt was
grown superficially over M. phaseolina or R. solani; but not inhibited
their growth, while the growth of F. oxysporum was clearly inhibited
with superficial growth of the first fungus.
4- Mycelial growths of M. phaseolina and F oxysporum were
significantly reduced by seed and root exudates of sesame cultivar
Mutation 48 more than Giza 32 cv. compared with control treatment.
5- Mycelial growth of F oxysporum was more affected by antagonistic
fungi than M. phaseolina. The different isolates of Trichoderma spp.,
particularly T viride was the most effective in this regard followed by
GliocJadium penicilloides and Chaetomium bostrycoides.
6- The effect of age and concentration of culture filtrates of different
antagonistic fungi on mycelial growth of either M. phaseolina or F
oxysporum showed that growth of M. phaseolina was more affected
by filtrates collected after 10 and 20 days, than 30 days. The culture
filtrates of Chaetomium bostrycoides and Gliocladium peniciltoides
added to growth medium was more effective on mycelial growth of
M. phaseolina than filtrates of the other antagonistic fungi. Effectivity
of filtrates was increased with increasing their concentrations from
10.0 to 50.0%. Mycelial growth of F. oxysporum was responded
similarly filtrates from 20-days-old culture was more effective than
those from 10 or 30-days-old.
7- The linear growth of M. phaseolina or F oxysporum was reduced
significantly with increasing concentration of different tested
fungicides. However, growth of M. phaseolina was completely
suppressed at concentration over than 50 ppm of Benlate and Rizolex-
T and 100 ppm of Ronilan, Swnisclex and Topsin-M, whereas slight
growth was observed at 1000 ppm of Monceren-Combi and
Chlorothocieb, The growth of F. oxysporum was completely ’stopped
at concentration of 10, SODand 1000 ppm of Benlate, Rizolex- T and
Monceren-Cornbi, respectively, but the growth not completely
inhibited even 1000 ppm of other tested fungicides.
8- Percentage of pre- and post-emergence damping-off and root-rot and
wilt diseases was increased and healthy standing plants were
decreased with increasing the inoculum amount of either M.
phaseolina or F’. oxysporum from 1.250/0 up to 10.0% of soil weight.
At 10.0% inoculum potential M. phaseolina killed all plants at
seedling stage.
9- The percentages of damping-off disease incited by M. phaseolinu , N..
solani and S. rolfsii under greenhouse conditions were significantly
equalized (60.00/0) when each of them was alone in infested soil
followed by F. oxysporum (35.0%). In soils infested with different
combination of these four pathogenic fungi, percentages of dampingoff
disease incidence was decreased to different extant compared with
M. phaseolina • R. solani or S. rolfsii each alone. The only exception
in which percentage of damping-off was increased (65.00/0) was in soil
infested with M. phaseolina , R. solani and F oxysporum. The
incidence of root-rot and wilt, however enhanced in soil infested with
M. phaseolina + S. rolfsii or R. solani + S. rolfsii and retarded in • 1
other combination particularly M. phaseolina + F oxysporum.
10·Based on percentages of healthy plants standing in infected soil under
greenhouse conditions, the different tested cultivars and strains could
be described highly resistant cvs. as Mutation 48 cv. and B3S strain.
resistant as B10 strain. moderate resistant as Giza 32 branched and
Aceteru-M cvs., moderate susceptible as Giza 32 unbranched cv.,
B II strain and Mutant-AM (616890) CV.~ susceptible and highly
susceptible as B16 strain and B51 strain, respectively.
II-Oil content in sesame seeds from root-rotted and/or wilted plants of
different tested cultivars and stains due to infection with M.
phaseolinu and/or F. oxy.\jJO/’U/JJ was significantly reduced seed of
healthy plants grown in control (non-infested).
12- Sowing date at IS!l:!May followed by l:i! May resulted in best disease
control and increased percentages of healthy standing plants grown in
soil infested with M. phaseolina and/or F. oxysporum.
13- Trichoderma harzianum followed by Chaetomium bostrycoides were
the best antagonistic fungi for reducing root-rot and/or wilt disease
incidence and increased percentage of healthy plants compared with
other antagonistic fungi.
\14- Soil inoculation with vesicular-arbuscular-mycorrhyzal (VAM) fungus
Glomus macrocarpum decreased percentage of damping-off and rootrot
and wilt diseases caused by M. phaseolina and/or F. oxysporum .
Colonization of sesame roots with different tested VAM-fungi were
clearly stimulated by F. oxysporum and inhibited by M. phaseolina.
15-Benlate and Rizolex- ~ fungicides seemed to be the best fungicides for
controlling disease incidence caused by M. phaseolina and F.
oxysporum with clearly increasing of healthy standing plants.
16-Under field conditions, the reaction of tested sesame cultivars and
strains against infection with root-rot and wilt diseases was slightly
differed compared with greenhouse conditions. Aceteru-M se~ame
cultivar was the most resistant, whereas Giza 32 cv. was the most
susceptible. However, best seed yield was produced by 5/91 and Bl1
strs., whereas Giza 32 and Accteru-M cvs, were the least in this
respect. The percentages of oil content in sesame seeds of infected
plants was significantly lower than those of healthy plants. The
highest seed oil content was obtained by healthy and infected plants
ofB35 str.compared with other cultivars and strains.
17- Applying the highest rates of phosphatic and potassic fertilizers and
lowest rate of nitrogenous one was important for decreasing disease
incidence and increasing healthy standing plants and oil contents in
their seeds. Combined fertilization treatment consisted of 50:300: I00
or 50:300:50 kg/fed. as urea) calcium super-phosphate and potassium
sulphate, respectively were the best in ~his respect. The highest
nitrogenous rate (100 kg/fed. as urea) increased or had no effect on
disease incidence compared with the low rates of nitrogenous
fertilizer either used alone or combined with phosphorus and
potassium fertilizers.
18-Ammonium sulphate fertilizer was the best nitrogenous source for
minimizing incidence of root-rot and/or wilt diseases and increased
seed yield and seed yield oil content followed by organic manure)
ammonium nitrate. Urea was the least effective in this regard,
compared with control (without ~-fertilization).
19-Rizolex- T or Benlate as seed treatment at rate of 3 g/kg seed
combined with Chlorothocieb as soil treatment at rate of 5 kg/fed.
were the most effective and superior treatments for controlling rootrot
and wilt diseases and increased seed yield of sesame.