الفهرس 
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Abstract
smmARY
Barley is vulner~ble to attack by s relatively
large n_ber of foliar diseases. The present investigation
was carried out to survey barley foliar diseases
in Egypt ,nth special reference to ledf stripe caused
by Helminthospori~ gramineum . Results ma1 be summarized
as follows:
(1) Barley foliage is attacked by eleven pathogensthet
cause the following diseases in Egypt,~.~.,lear
stripe, net blotch, spot blotch, powdery mildew,
dOllI13’ m11delf, leaf rust t stem rust, stripe rUs.t :J
minor leaf spots, barley stripe mosaic virus and
barley yelloW dwarf virus.
(2) Barley l eaf s1;ripe causes da..,..geof leaveS end
mq prevent ’the emergence of” heads from the leaf
sheath. Str:lpe appears heavily in the humid districts.
Its prevalence 18 more in Delta Regioa
than in Southern Regionr£ EgYP’t •
(3) ””elTe 1solate8 of !!. gaminEl1l1l 1I~. :1solated froa
striped a_ple.. Conidiophore•.••ere tark brown•
• 1;ra1gb.’ ••• ranged f%lO- 100 1;0 300 u. wllerea.
conicl1a .••ere 8ub-b,JalUe to yellOWish brown s1;ra:1-
gilt. sub-c711nderical and ranged froa 12 x 64 to
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20 x 100 U. Germtubes, commonly, developed from
terminal cells.
(4) Artificial inocula.tion was conducted, ’using eight
methods. The modified technique, which was used
for the first time during the present inv estigatioD,
achieved the highest percentage of infection.
(5) The tested isolates of li. gramineum showed variation
of pathogenicity on aleven barley varieties.
Different epltural characteristics were also exhibited,
as well as dissimilar activities of pectolyt1c,
cellulolytic and oxidative enzymes.
(6) Cultural fil trat e8 ot li. gramineum 1so1ates showed
distinctl1 M:tterent ettec:t S OD barle.,. seed germination
and morphologic characters ot seedl1Dg8~
(7) Uelm1ntnosporiu.. gramine.. was found to attack
several gene,._ of Poacea. (Graminaceae). Typical
stripe 83’JIlPtiall, howaT” , developed only OD. barle7
(HordeUllSPP’.).
(8) stripe sJDIP’-”. ocnilcide -with redadoa :l.Jl
conce~ratio •• ot sugara in barley seedlings.
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(9) Concentrations of total free amino acids fl~-
ctuated during the development stages of stripe
infection. Aromatic amino acids contents sharply
increased, seven days after inoculation.
(10) Total , free, conjugated and or”tho-dihydroxy
ph.enols increased, generally, in infected tissues.
It seems that phenolic compounds play an important
role ooncerning the inhibition of developmen:t of
stxipe infection on barley seedlings inoculated
with. mycelial and spore suspension of 1!. gramineum.
(11) Changes of poly phenol oxidase activit1 were undetected
in inocUlated barley seedlings. Peroxidase
soowedappreciable increase· in changes o-r activity
as a result at inoculation. Changes o-r c atalBse
activity were more in inoculated tissues than that
in uninocu1ate4 ones. On the cont1’S27, a I!b.arp
decrease of changes of ascorbic acid oxida•• wall
recorded in inoculat eel tissues’.
(12) OQto:f 100oa1tlvarll aIld crosses of barI8”, 48
mOlted resl.ano. to le~ stripe disease. These
varieties .. -cIUll.. be used a8 resistant pare.e 1Jl
breeding prGBrBllltor developing new resi stant
varieties.
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(13) Stripe infection and mycelial growth of l!. &!!-
mineum ’.”Iere reduced by ”,Sing six different fungicides.
Vitavax thiram was the most effective
fungicide, followed by Vitavax and Dithane M-45.