الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Vegetable crops are cultivated at about 1040887 feddan
in Nil!. summer and winter seasons. Cucurb1 ts
(watermelon, sweet melon. squash and cucumber) are of
the most important crops which are cultivated at about
289755 feddan in Nili, S1.DDlerand winter aeasons.(The
Central Agency of Agricultural ~conamic, 1986).
Results oouldbe slwmarized in the following :
1. Three methods of isolation were used to isolate fWlgl
associated with cucurbits seed samples collected from
different localities of Egypt.
a. Fungi isolated from cucumber seed samples were :
Fusarium o;ysporum, F. semltectum. F. monilifo~e.
Cha~tamium sPP-. Alternaria alternata. Fenicillium spp-,
Cladosporium spp. and Aspergillus spp.
b. Fram squash seed samples, fungi as~ociated with
seeds were Fusarium monilifonlie, i.- seu~itectl,DJl.}o’. ~OlW11,
l. o;ys porum , Stemphyllium botrYosum, Alternaria alternata,
Aspergillus spp., Chaetowium spp., Penicillium spp.,
Cladosporium spp. and aacrophomina pbaseolina.
c. With regard to sweetm~lon seeds fungi detected were:
Fusraium semitectum, I. oxy8porum, Chaetomi!:!m.spp ••
Aspergillus spp., Fenicillium spp., Alternaria alternata,
Bo’trlt18 cinerea, Clado,;;por1um app., !. monj,liforme and
~icroA8cya trigonosporua.
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d. Fungi isolated tram watermelon seeds were:Alternarie
alternata, I_ semi tectWIl, F. DloniliforDle, Cladosporium
spp., AspergilluS spp., Penicillium spp·, Chaetomium spp.,
Epicoccum spp., I. solani, Drecbslera rostora1a-, a·
hawa1iensis and Phoma spp·
2. Fungi adbered to seed surface of cucurbit8 samples
using washing test method were : Alternaria alternata,
Cladosporium spp., Epicoccum sp., Fusarium spp- and
Stempbylium botrYOsum.
J. As for pathogenicity tests, 22 isolates of Zungi were
tested twice, ~der greenhouse conditions in winter
and summer on seeds of squash, cucumber, sweetmelon.
and watermelon. All these fungi were pathogenic with
different degrees :
.8. On squash in summer season, Chaetolllium isolate l~O.
(~) and Cladosporium sp. followed by D.iicroa~cUS tl’igoJlOSpOl’US
eave the highest pre-emergence damping-off i.nfection.
Fusarium moni11formeand Botrytis cinerea gave the highest
percentage of post-emergence damping-off. In winter season,
pre-emergence damping-off was highest with Botrytis cinerea
followed by Cladospori\IU aPe The highest percentage of
post-emergence damping-off observed with pusarlum °XTsporum
isolate )10. () and Cladospor1&D ap. followed by Pboma sp.
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b. As for melon,the highest percentage of pre-emergence
damping-off in summer season with Microascus trigonosporus
and Chaetomium ap. isolate No. (2) followed by Fusarium
moniliforme, Botrytis cinerea showed the highest percentage
of post-emergence damping-off infection followed by!.
ogsporum isolate No. (6). In winter season, Fusarium
solani isolate No. (2), Botrytis cinerea and ~icroascus
trigonosporus showed the highest percentage of pre-emergence
damping-off. The highest percentage of post-emergence
damping-off was noticed with Fusarium solani isolate No.
(), Cladosporium ap. and !. monilifonne.
c. On cucumber in summer season, Cladosporium sp.,
Chaetomium ep- isolate No. (2), Rhizoctonia solani and
~icroascus trigonosporus gave the highest percentage of
pre-emergence damping-off. pusarium solani isolate No.(6)
and F. 0Xlsporum isolate No. (5) followed by F. solani
isolate No. (4) and Botrytis cinerea gave the highest
percentage of post-emergence damping-off. In winter
season, infection with Chaetamium sp. isolate Ho. (1 and 2)
and Botrytia cinerea showed the highest percentage of preemergence
damping-off. Whereas, Cladosporium sp., lticroascus
trigollOSpOrus sbowed the highest post-emergence damping-off.
d. On wat~r.melon in summer season, Fusarium mouiliforme,
Cbaetomium sp. isolate No. (2) and I. Bolan1 isolate ~o.
(1) gave the highest percentage of pre-emergence damping-
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otf. In post-emergence damping-off, !. solani isolates
No. (6 and 4), F. oxysporum isolate No. (5) and Botrytis
cinerea gave the highest percentage of infection. In
winter season, percentages of pre-emergence damping-oft
was high with Botrytis cinerea, ~haetomium sp. isolate
No. (2) and Cladosporium ap. followed by phaetomium ap.
isolate No. (1) and !. moniliforme. ~he highest percentages
of post-emergence damping-off were noticed with
F. agsparum i~olate so , (4)-, ChaetomiLDllap, isolate .No.
() and 1. moniliforme.
4. The effect of fungal growth of four fungi on squash
seed germination was st~died. The fungus Botrytis
cinerea inhibited greatly both root growth and hypocotyl
and also reduced greatly the percentage of seed
geX’1uinationfollowed by Fusarium moniliforme, Microascus
trigonosporus and Cbaetomium ap ,
5. Also the filterate of Botrytis cinerea, )’usarium
mor~ilifonIle,liicroascus tri;;onosporus end Ghaetomium
sp. at different concentrations inhibited squash seed
germination and decreased the radical length. The
filterate ot lIicroascus tr1$onosporus was the most
red~ctive on seed £ermination and radical length
followed by Pusarium moniliforme filterate, whereas
ChaetOffi1upap. filterate followed by Botrxt1s cinerea
filterate showed the least reductive effect on both
seed gemination and radical length.
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6. Disease severi ty was found to increase gradually as
inoculum of Botx”ytia cinerea, .Fusarium mOni11forme,
M1croascuB tr1gonosporus and Chaetomiumap. increased
in the soil.
7. The activi ty of PIlE, PG and CXenzymes was measured 1n
the filterates of Botr~tis cinerea, Fusarium moniliforme,
Microascus tr1gonosporus and Chaetomiumsp.
Q. PKE enzyme was produced in Botrytis cinerea,Chaetomiurn
sp. and K1croascus trisonosporUB f11terates, whereas, l.
moniliforme :til terate was :fr~e:from I’lU:!; enz.YJl1e.
b. Act! vity of both POand ex enzymes increased as the
period of incubation increased.
c. The activity of Fa enzyme in Cha~tomiumsp. filterate
was highest followed by JI1croascUB trigonosporus.
d. The highest activity of C.KenZ.Y1lleWs ~l’eobserved in
til teratea at Batr.ytis cinerea and FLU:i&riuwmonilif’orme
as compared to other fungi.
B. The activity of PC and ex enzymes was determined in
the extracts of sQLl8ah roots which grown in soil infested
with the aforementioned tested fUDg1 for 4 weeks.
a. The highest activity Of PG enzyme was obtained in
root extract inoculated with lYaar1um moniliforme,
JUcro8Bcua triBonosporua. BotrytiAI cinerea and Chaetomium
8P_, reapeCilyely_
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b. The highest activity of ex enzyme observed in root
extracts infected with Chaetomium Spa and l. monilitorme.
9. Benlate. Homai 80 and fops1n M were the most effective
fungicides inhibited the arowth of ~otrYt18 cinerea,
Pusarium monilifo.rme and Chaetomi1.DIlsp.. tollowed by
V1tavax/Captan and Vitavax/Thiram.
a. Benlate inhibited completely the rate at growth of
the three :rungi at 10 Pj:ID..
b. The rate of growth of Botryiis cinerea was inhibited
completely at 25 PfID.Homai 80, at 50 ppn Vitavax/Captan
and V1tavax!Thiram,· at 200 ppn Campogram. at 800 Pita
Orthoc1de 83, at 1000 ppm Terra-coat L 21 and NTH +
Captan.
c. The rate of growth of Pusarium mOllilifome was
inhibited completely at 25 ppm Topsin It and Homa1 80, at
800 ppn Terra-coat L 21 and at 1000 ppm Campogram.
d. The rate of growth of Chaetom1um Spa was lnhibit~d
completely at 10 ppm Topsin M and Hamai bO, at 400 ppm
Campogram and Terra-coat L 21. at 800 ppm RH 50/50 and
at 1000 ppm NTN + Captan.
10. Benlate. BOllIa! 00 lind Topa1n >.; :followed by Vitavaz./
Capt an and Vitav&31Thiram were the most effective
fUl1B1c1dea &BUllSt spore ~o2’llat1on of Botrz~ cinez’ea.
J”USar1um mOnilitonne and Q.haet0L111111 ap,
•
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11. Chemical control under field condit1oDB ahowed that
all f’ungicides uaed reduced pre-, post-Eergence
damp1ng-o:tt and increased survival plants 1n both
seasons 1982 and 19B3as seed sOaking and as seed
dressing.
12. Bioassay of residual detezminat~on of five systemic
fungicides, used as seed dressing with recommended
dose, 1n roots of squash plants was studied by USing
Aspergillus niger. The tested fungicides were absorbed
through the seed coat and intered the root tissues.
The fIIIlount ot residues in the roots was higher in case
ot using V1tavax/Captan and Benlate followed by fopsin
II and Heaa! 80. The amoWlt ot residue. decre.sed w1th
the iIlcreasing ot plant age.
13. The et’f’ect ot fungicides suspensions in w& ter on seed
germination was studied.· Generally. fun!:icides used
decreasec tue percf!ntap.:e of seed genn.i.nati on ami had
F.l pj”(Pto,’J;oxiceffect by usinc. them for 7 days.