الفهرس 
AcnoledgementOnly 14 pages are availabe for public view
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Abstract
S udies on the sensitivity of certain wheat entries against
leaf a d stript! rust in Egypt whet (Triticum aestivum L.) is liable to
the att ck of many diseases in Egypt i.e. rusts, smuts, powdery
mildew and some other diseases of minor importance. Rusts
induce high losses to wheat in Egypt. The difficulty of controlling
rusts a e due 10 it’s obligatory habit and to its dynamic nature.
T e present study focused a spot light on certain topics
releva t to thl~ application of genetic control of both leaf and stripe
rusts t rough out the identification of the predominant races of leaf
rust a d the isolates of stripe rust. The study also involved the
distin on of certain effective genes of leaf rust via the inoculation
of 18 leaf rust monogenic lines. The ultimate goal of such a study
is to ontribute the breeding programme in the scope of rust
resista ceo
e stUdy included the testing of 36 wheat entries against
the m re prevalent and virulent races of P. recondita (leaf rust)
and a so against 3 isolates of stripe rust (P. striiformis) at seedling
stage. On the other hand the same entries were subjected to the
evalua ion sg,linst the two concemed diseases at adult stage.
on
e stt. dy also included the effect of different temperatures
incubation periods for wheat entries. The evaluating of
ic full! Jicides and 2 bioagents against leaf and stripe rusts
rried 0~ during the study.
effect of stripe rust (P. striiformis) on the chemical
con . utions 1)1wheat kernels was also studied.
of the preeent work could be summarized in the
1- Seve physi1)logic races of leaf rust (Puccinia recondita) were
identi ed du ing 1996/1997 and 1997/1998 growing seasons.
Race no 77 was the most predominant one followed by races
no’s 7, 20, :~1,130 and 184.
2- The tudy gave evidence to the distinction of Lr’s 19 and 24 in
contr IIing leaf rust uredospore populations throughout two
seas ns.
3- Ten nd sb wheat entries proved to the resistant to leaf rust
races viz. 77 and 57 in respect likewise 9, 13, 13 entries were
resist nt to the 3 isolates of stripe rust (P. striiformis) at
seedl ng sta!~e during 1996/1997.
4- The atchiug between leaf rust monogenic lines and certain
whe s, whem inoculated with 34 single pustules of Puccinia
reeo dita resulted in the postulation of genes i.e. 29, 39t 3 kat
16, 1 and ~:4in most of the tested entries as common genes.
5- The incuba tion periods were prolonged with the decreasing
tern rature and the reverse was true with the test cultivars
whe inocul ated with races 77 and 57 at seedling stage.
6- The field Elvaluation gave evidence to the superiority of entries
l.e, akha 01, Giza 144, Giza 155, Tosson and Sakha 24 when
ad ’:0 severe inoculation with stripe rust during two
ns. The rest of tested entries exhibited a reaction ranged
n .,. ace Sand 80 S·. The wheat entry i.e. Sakha 24 was
cha cterizfK1 by the lowest Area Under Disease Progressive
Cu e (AU[ ~PC),however the reverse was observed with Sids 7
and -9. C~nthe other hand, the entries showed significant
diffe nces in stripe rust rate of increase and certain yield
pa meters i.e. 1000 KW. and test weight. The highest loss
(%) re:orded with cvs. Sids 5 and -9, conversely, salcha 10
exhi’ tt e least rate in this regard.
7~As reg rd to IBafrust evaluation, the tudy gave evidence to the
distin ion of entries i.e. Lines 20 , -204. -206 which rated
(TrS). The n~st of materials rated 5S to 80S. ev. l.e, Tosson
exhibi eel the lowest (AUDPC) howe er the reverse was noticed
with s. l.e. Sids-1t Giza 139. Som entries showed significant
differ nces disease rate of, test wei ht and 1000 K.W.
8- The tudy gave evidence to th increasing efficiency of
fungi ides Ll~.Fangshow. SumiooB,aramba, Punch and Impact
in re pect ”,hen tested against bot~ of stripe and leaf rusts. On
the 0 her hund, Plantvax, Plantgu~rd and trilogy occupied the
seco d rank in this respect. .
9- The tudy Slave evidence to the increase of both peroxidase
and olyphE~noloxidase in resista t entries comparable to the
sus ptible ones. On the othe hand, irrespective of the
pres nee 0f. significance betwee entries in the increasing
activi of pcflyphenoloxidase, but . activity was rare. This may
be d e to that cereals did not co tain polyphenol oxidase and
its a ivity was related to host path gen interaction.
1Q-Ana omical characters were not nspicuous or clear cut to
diffe entiate between resistant, moderate resistant and
sus ptible entries the ratio of col enchymalsclerenchyma may
be nsiderad a clear measureme t between entries.
11-Con mi”, I the effect of stri rust infection on chemical
con titution of wheat kernels in ested verso the study gave
evid nee to the presence higher humidity, lipids,
ca hydrate contents in the tected grains. However, the
stri rust inoCUlatedones exhi ited higher contents in ash,
fibe and IM”Otein.