الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Macrophominaphaseolina is universally considered
amongthe most commondestructive pathogens that cause
root rot, charcoal-rot a~d damping off diseases on sUnflower.
Fysarium Q;ysporum is considered also one of the
moat pathogenic fungi that infect roots of sunflower plants
caus:ing damping-Off, v..1lt, and sometimes root-rot.
The present investigation was planned to study the
effeQt of some physiologic al and environm~ntal factors on
the tiwO fungi isolated from sunflower diseased plants and
their control.
The obtained results could be summarized as follows:-
1- Isolation and pathogenicity :bests indicated that l.
OXysEorUm, ~. rOlf§i1, ~izoctonia solani, ~. phaseolin~.
and F. solani are responsible for causing damping off, wilt,
and root-rot diseases to sUnflower in A..R.E.
2- M. J2haseolina and l. 0,xysporumwere isolated more frequently
j~rom diseased plants collected from different localities
In A.R.E. than the other fungi.
3- M,. phaseolina was shown to be seed transmitted and was
isolat ed from them. Also, sunflower heads could be in! acted
with M,. phaseolina. This may cast a light on the method by
which ~. phaseolina is seed-borne.
4- l. ~~porqa wa~ found to be the most destructive pathogen
on sunflower plants in pre-eme.rgence phase, and was
followed by .ile;j,erotiulI!,£olfsii •..,E • .!Iolani. Bhi~octonia
sola~t and M. phaseolina.
On the other hand, -M-. p-h-as-e-ol-in-a was most destructive late~r after a weeks.
5- fhe interaction between the different pathogens in pots
ShOwedthat whenM. pha§eolina inOCUlumwas Combined to
gether
with each fungus alone, decreaSed disease
incid.idenae.Whereas in oth~r combinations
post-em ergwere
c10mbined together and
ence damping -off increaSed especially Whenall tested fungi
6- fhe b•.st mediumfor the linear growth of M... .phaseolina
was 45 days old extract of plant parts of H.il941 variety.
wherea;~ 15 days and 3D days old extract media Of Giza 1
varietJr were the best for 1:. 0xysporum.
reached 100%.
7- PiltJ>at·ss of the tested fungi decreased the percentages
of seed ge.rmination of all the six tested varieties.
a” Giza 1 variety was l~ss affected with filtrates of both
fungi, however these :filtrates caused wilting of seedlings
of all tiested varieties.
9- Generally the effect of both fungal filtrates increased
With ageing of filtrates. Also this effect diffored as
regards sunflower vaJ:”ietyand Giza 1 variety was lass
a.ffected.
10- The filtrates of M. phaseolina were less effeotive on
the different testGd varieties.
11- In pot experiments • Giza 1 and l4iak were less affeoted
by J. pha§eolina on oontrast with Import 61whioh was
lells affeoted with 11. oJQ”sporum. Also under field oondi_
tions Giza 1 and l4iak were less sUSoeptible to infeotion
with~. phasegliga.
12- The peroentages of infection increased by inoreasing the
depth of SOWing in soil infested with either~. phaseolina
or ]!. ox:ysporum.
13- The peroentages of pre-and post-emergenoe damping-off
inoreaSed by shortening the watering intsrvals in oase
of soil infested with 1:: oJQ”sporUm on Oontrast with II•
.Rha§.e.91ina.
14- The ”Heot of fertilization in artifioially and naturally
illf.’esltseod11 showed that addition of N-fertilizer alone
deoreased the peroentage of diseased plants then inoreased
it again by addition of more N both in pots and field
e.2q)sr:Lmentsfor the tested fungi.
1,5- The beat oombined treatment for obtaining the best results
of disease reduction and yield components was that of R1PaK
136kg. + 193 kg. + 3l.0kg/fed respeotively) in soil
infested with either l. 0X7sporum or ~. phaseolina and
also under tield conditions.