الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The present iavestiJution wns plalTI1ed to study the
causal organi~s of sunflower, root diseases, the effect
of some physiolo3icnl factors, scprophytic behaviour
and their corrtz-o L, The findiIlGs ccn be summarized as
follows :
1- Lso Lat Lon of the causal orgc.nisms of sunflower
root disease was carried out from diseased roots oollected
from Giza Governorate during 1975. Sclerotium rolfsii~
R.solani, ~.ph2seoli, F. fusarioides and other speoies
of ~~pergillus. Fusarium, Alternaria and Curvularia were
isolated with prevailing of Ill•.phaseoli.
2- PathoGenioi ty tests using Giza-l sunflower
variety indicated that -S-.rolfe!! caused foot root, wilt ’ and blight; R,zo.1.an1 ca4sed stunting) M.phaeeoli caused _ ... - -. ’ . :IIi..
. l •
ohare 0$1 rot and’ .;.,;;.11~. ~”ioides oaused stu.atiDg, thel1
~Ut. In addl1;i~ -tbe}o~’ tungi’ ca~sed pre- or p-on•• .• ·~~,I ,,’-.’ ,”
emergence damping-oft ~ different ratios. ,SC1~o’1.
·;”,.’-1 .”-
rolfsii was found to ot!the most a::;:;ressive pathogen
than the other lG~._f~l. ’
,~J- ;.i;-·;;’·i-’
.... J- The
in ’v-ivo
f””’4’ .. ;_~.: ” . ’” ., -.’ .....
.- lj.
-S.rolfsii + R. sclani increased the infection than each
of them alone.
4.•. Solerotiwn rolfsii seoretedo:::o.lioaoi.d, in
cU1t~e$. Potato cylinders were 50ft rotted when
immersed in S.~olfsii filtrate or. different concentrations
of oX8lic acid. Thus, the lOES of coherence
was fast in hiGh concentro.tions of tbe acid •.
. ,
5- Filtrate of S.rolfsii caueed ~o cermination to _._~
sunflower seeds. ~iltrates of the othex fW1gi however,
caused drying of seedl~UGs shoots of Giza-l variety
after 48 brs., while dried all seedlinGs of Miak variety.
B- ~ar~\\U flts$’:10id6S snowed only the b.i3hest
cololliza~1on rntl~sJ:~ Wbile,ll.solani was a. po~
ooloa1zero! the ag~:Plate8. __oo].onizat1on rat1~s
1ncreasec!lgradually ’ith tile i.reese in the amowxt
. ~: .. .,..,
of i-.ecu.lwn.!he .~..’, ft.Utgl.”Wei h13h degree 9f
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6- I>ercentac.;& of diseased plants Gradually increased
with the increase in ru”””Uountof Lnocukum,
7~ All the tested suriflower varieties W~e found to
be s~sceptible t·o the disease. Giza-l vnriety gave
modQa:te re~etenoe ’b$)all f~1 exeepl S.rolfsii. ~ J~ • - .’ - 4 (
·to1~ to ·.·e..1WM-
9- Myc6’lLcl,r;rowth of the fou,r fu::).::;1 deoreased with
increasing the concentr~tions of fU1~icides when
incorporated in P,D.A. med1um.Moreover, fU~sioides
differ~d in the ooncentrations at wh.l.ch fungal growth
was inhitit ed, Bnvistin and Topsin :,~.Y1Grethe best
fUQ5icides to ..R••..solro1i, M.phaGeo1i ~d F.fusarioides as . .”- -
they inhitited ,:;rowth at lower conccl1tra-~ions, while
vitavax/captcn und vitavax/thiram we~e the most effective
fungicides asainst S.rolfsii.
.:~-.
10- The four systemic fun3icidesused, remained
active in the plants fo:r;-about 3 weeks. Theaefungieides
translocated from the seeds and loc ali2led in the root
tlfJsuea more than’ in stems or leav.es and gradually
dec~ea5ed upw~ds.
11- Seed t-~eatm.l1”fw1th eaeh ()f vitavax/c~ptaa at·
O.~ or Bav~st~:a. 0.’ was the. h~n f~ic1d.,: f<Jr
._~:.’
controlling tMdiseasej.