الفهرس 
Materials and mithodsOnly 14 pages are availabe for public view
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Abstract
The present investigation was carried out through the five
successive seasons 1988/1989, 1989/1990, 1990/ 1991, 1991/
1992 and / 1993 to investigate the following pointsii)crossabi1ity of
wheat with rye, ii)To Synthesize pri_ry triticale, iii)to study
the cbrODOSoaal instability of the studied _terials and, iv)to
evaluate the studied .aterials on the basis of c-banding teeJmique.
The materials used for this study were 11 hexaploid wheat
varieties ,4 tetraploid durumwheat varieties, and 2 diploid rye
varieties.
Plants weregrownandcrossed underfield conditions- For each
cross coabination. the nuaber of florets pollinated and seed set
was recorded 18 days post pollination . The developed seeds were
reooovedand...myos were rescued and culture on artificialJaedia to
produce haploid plants, then treated with 0.05’& colchicine + 1.5’&
DMSO for 5 hours.The obtained results could be summarizedas follows:
I) crossabi1ity of 1Ibeat vi1:b rye :
Wheatvarieties exhibit significant differences with respect to
their crossability’ with rye, furtberaore the salle wheat variety
shOWS different crossability percentages with the s8Ji8rye variety.
seed set for hexaploid wheatvarieties rangedfro. 2-3t to 15t
in the case of rye Prolific whereas it ranged froa 1.6’& to 11.1’&
for rye ~rial. The variety Giza 163 displays the highest seed
set with both rye varieties i.e. 15\ with pcolific and 11.1\ with
~rial. lIhi.lethe variety sakba 69 gave the lowest seed setpercentage with both rye varieties i.e. 2.3% with prolific and 1.6% with Imperial. Tetraploid wheat varieties show lower seed set percentage than the hexaploid wheat varieties. Seed set percentages ranged from 2% to %.3% for rye prolific and fro. 1.2% to 6% with rye Imperial •
The variety Suhag 1 exhibits the highest seed set percentage 6%
with rye Imperial, since the variety Beni-suief 1 showS the lowest
seed set percentage 1.2% with rye IJDperial. These data indicate that the genotype of the variety Giza 163
could be KrlKr1kr2kr2 whereas the rest of wheat genotypes could be
KrlKr1Kr2Kr2 II) Dle synt:beBisof prJ.a1Y tritica1e : it has been observed that ,there is a wide variation in number
of seeds having well-differentiated embryos. The cross suhag 1 X
prolific displays the lowest percentage 30%, while the cross Suhag
3 X Iaperial shows the highest percentage 59%. with respect to haploid plants, the different crosses show
clear differences in percentage of resulted haploid plants. These
percentages ranged frOll 53% to 71%. sinlarly , the different
crosses exhibit clear differences in their response to colchicine
treataent, the percentages of successfully doubled plants ranged
fro. 50% to 80% .The crosses ,also, show different ntmbers of
hybrid seeds or obtained fro_ doubled plants, the cross Beni -suief
1 X I.perial exhibits the highest seed nu.ber ,11.5 seeds/plant.
on the other hand , the cross Suhag 3 X prolific gave the lowest
nuaber 4.5 seeds/plant.XXX)-au:c.-~1 inStabi1ity : i) Mitotic instability :
Thedifferent crosses display different degrees of cbro instability as .”.pressed bY the percentage of aneuploids. TheSe percentages ranqed frOll 17’1;to 31.7’1;. the ••••jority of these plants ...,re hypoplOids.(2,.”.40.41.41 +telo. ) • Theoverall - of aneuploidS
••as 21’1; • In the salle ti- the c~l stability expressed by
euploid plants .it ranqed fr<Dl69.4’1; to 83’1; in the crOSses Suhag 1
X~rial and Suhag 2 X I~ial. respectivelY
ii) Meiosis abnormalitieS :
number of cells having univalents• lagqing chrOJlOSOI•l8S
cbrQllatid bridges. and .icronuclei ...,re recorded· There are. alSo. condensation probl-. _inly sickness occurred at high freqUencies
••ith varYinq intensities in triticale _terials • These freqUencies
ranged from 21.5% to 35.3%.
Thepercentages of cellS having univalents ••ere exu-ly lin
the parental_tsrials and c<mIlOnin triticale _terialS.siJdlarly • the occurrenc” of la<J9inqc)lr<mOsowoaensd chr<mBtid bridges ••as very 1- in the parental aater ialS
• since it ••as on in triticale aaterials. Also the frequencies of abnoraahaving -.icronuclei) ...,re very 1- in the parental
aaterials • >lhereasthey ...,re very =-’” in triticale aaterialS •
XV)- e-tJaIM’i ag t:;eebnique :
Thepresent teebJlique enables to identifying easily different
cbrOaosoae& in different genoae& •
In general. rye ~.as _ large tel.-r99
andweat chrOllOsoaeshave centroaeric (interstitial) heterochro--
tin bands. Although, there are somevariations in banding pattern
of the two chroaosQJl88 belonged to the salle pair, particularly in
rye varieties. Ho_jar differences in c-baDdingpatterns could·be
observed betweentetraploid wheat varieties,Suha9 1 and Beni-suief
1. In general, The seven pairs of rye chrOmosomes were present in
all triticale lines and accurately distinguished.