الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
SUMMARY
ttGAlIIIMARAY EFmors ON EG1Pl!IAN CWVER ”
Twofield experiments were carried out at the Researoh
and Experiment Station of the Faculty of Agricultural
SCience, Moshtobor during 1978/79 and 1979/80
seasons to study the effect of gammaradiation on germination,
growth charaoters, yield and protein content at
M1plants of the two cultivars of Egyptian clover, namely
’’Meskawi’’ and ”Fab!!’. In addition, morphological mutations
induced in ~ generation were also studied.
seedS of the two cult1vars were irradiated with
gamma ray do ses of 2.5, 5, 7.5, 10, 15, 20, 25, JO, .l(),
50, 60 bDd?O Kr., in 1978/79 season, while e dose of
80 Kr. was added 1n 1979/80 season.
For growing M1p lents, treated seeds as we11 as a
contra 1 of untreated seeds were sown 1n the field in the
second day after treatment in a completely randomized
block design in four replications. The plot area was
6 M~ ( 2 X 3 m)..
~ata recorded on 141 plants of ’’MesJrawi” cultivar
were: gerlllinat ion percentage, growth characters (maiD
-stem height, number of stemstm~t number of leaves/plant,
fresh and dry weight of stems and leaves/plant) t fresh
and dry yield and protein content in stems and leaves
of the three cuts and seed and straw yield •
.AiJ for nFahl” cultivar, every plot was divided into
two equal halves. The firstkhalf was devoted to produce
the single cut usually obtained from this cultivar.
After harvesting tb~s first cutF,plots were regularly
ir~igated (aB in Meskawi cultivar) in order to examine
whether radiation treatments might induce a renewed growth
and consequently, subsequent cuttings may be available.
On this half-plot, the data collected on ”MeskaWi”
cultivar were also recorded on the first cut as well as
on the subsequent cuttings.
The second half-plot was allowed to produce seeds
and therefore no forage yield was obtain6d.
In the second mutagenic generation, an experiment
was carried out to estim.ate the percentage of mutated
plants of the two cultivars. This eJq:Sriment was sown
with seeds 0 btainsd from sa If-pB.l11nated plants of M1
generation. !bring the ~ generatioo, a.ll plants from
”
germination till harvest, were screened to detect any
change in their characters.
The results obtained in this stUd3 could be summarized
as follows:
1- Lower radiation doses, i.e. 2.5 and 5 Kr. markedly
increased the germinatio n percentage of M1 seeds of
. ”1l/les.kawitl cultivar, whereas higher doses, i.e. 70 and
80 Kr. sigoif1can t ly reduced germinat ion percentage
in the two experimental seasons~
2- The dose of 5 Kr. achieved the highest germination
percentage of nFabl” cultivar, while 70 and 80 Kr.
doses pro duoed the lowest germination percentage, 1n
both seaSons of experimentation.
3- Growth charaoters in Ml generatio a, such as, main
stem height, number of stems/m~, number of leaves/
plant and~,the weight of fresh and dry stems aJd leaves/
plant, in the three cuts of ttMeskawitl cultivar, were
favourably affected by lower doses of gammarays, i.e.
2.5 and 5 Kr•• while higher doses, i.e. 60, 70 aDd
80 Kr. significantly decreased tOOst of these characters.
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Such results were evident in the two seasons of experiment
at 10 D.
4- Growth characters of tlFahl” plants of the first cut
were favourably affected by lower gammaray doses in
similar manner as in uMeskaw1” cultivar,
5- Radiation treatments stimulated the basic branohing
in ”Fahl” plants so trlo.atplants renewed growth after
outting. Consequently, a second and a third cut were
available as in multiout clovers. Different doses
of gammaraJs significantly affected the growth characters
of renewed plants 1n the two cuts obtained
from these plants. In general, lower radiation doses
.positive13 affected growth characters in the second
and third cut plants in t’Fahl” cultivar.
6- nash and dry yields of every cut in ttMeskawi” cultivar
were increased as a result of treating seeds with
lower radiation doses, whereas higher doses reduced
fresh and dry yields compared with the control.
Highest in~reases in total fresb yield were obtained
at 10 Kr. dose in both seaeo na , SUch increases reached
17 and 8 % over the total yield of the control in 1978/79
and 1979/80, respectiveJ..y.
In regard to total dry yield, such increases were
24 and ”10 % for the two successive seasons, which were
obtained at 5 and 7.5 Er. doses in 1978/79 and 1979/80
re spectively.
On the other hand. total fresh yield decreases were
21 and 28 % in 1978/79 and 1979/80 respective~, compared
with the contro 1, and were 0 btained when seeds were
tre ated with the highest radiation doses (70 and 80 Kr.).
As for total dry yield. these yield reductions reached
19 and Z3 % in 1978/79 and 1979/80 seasons, respectively,
when the highest radiation doses were used.
It was clear that fresh and dry yield increases
produced from the lower radiation doses were more evident
in the first cut than in the subsequent ones.
7- Fresh yield of the main cut (first cut) of ”Fahl” plants
WaS increased as a result of treating seeds with the
lowest radiation dose (2.5 Kr.) by 10 and 24 % in 1978/79
and 1979/80 respect1vf:).y, compared with the control, whereas
higher doses reduced fresh yield by ,38 and 42 % in
the two successive seasons.
Dry yield was increased by 28 % dn both se asons of
exper1m6otat 10n when seeds were irradiated witb 5 and
2.5 Kr. in 1978/79 and 1979/80 seaSOD, respectively.
8- Fresh yield of the second cut obtained from renewed
growth in It Fah1” cultivar reached a maximumof 3560
Kg/fad. in 1978/79 season when seeds were treated with
15 !Cr. dose. In 1979/80 se ason , maximumfresh yield
reached ,3430 Kg/fad. and was abt ained at either 10 or
15 Kr. doses.
In regard to the third cut of renewed growth induced
by radiation treatments in ”Fahl” cu1tivar, a maxi.mum
fresh yield was 0 btained when seeds were irradiated with
10 Kr. dose. Su.ch fresh yields were 8869 and 9573 Kg/fad.
in 1978/79 and 1979/80 respeotive lye
M for the dryyie ld of the second cut of ”Fahl”
cultivar induced by radiation, maximumyields of 910 and
553 Kg/fad. were 0 bteined at the radiation doses of 15
and 2.5 Kr. i.D 1978/79 and 1979/80 seasons, respectively.
In regard to the third cut, highest dry yields were
2681 and. 24?3 Kg/fad. in 1978/79 and 1979/80, respectively.
Such yields were obtained as a result of treating seeds
with 30 and 40 Kr. doses, respectively in the two saccessive
seasons.
9- seed yield of ”Meskaw1”oultivar was significantly
affected by radiatdoo treatments~ Increases in seed
yield reached 13 and 9 % over tha seed yield of the Control
io 1978/79 and 1979/80 seasons, as a result of treating
seeds with 15 and 5 Kr.Kdoses, respectively.
On the other hand, highest radiation cbses reduced
seed yield by 29 and 43 % 1n the two Sucoessive seasons,
compared with the contro 1.
In regard to straw 3ie 1d, increases of 19 and 16 %
were obtained over the control in J.9?8/79 and 1979/80
seasons when seeds were irradiated with ~~ and S Kr.
doses, respectively.
10- Beed yield of the renewed ”Falll” plants reached a
maximumof 8O~5 and 73.9 Kgtfad. in the two successive
seasons when 5 and 2.5 Kr. doses were usee!, respectively.
~he str8.J yield reached 890 and 9.ll Kg/fad. in 1978/79
and 1979/80 seasons as a result of treatlI:g ”Fall1” Seeds
with 5 Hr. dose iD both aeasona ,
11- seed yield of ”Fahl” plants which were allottE!d to
produce seeds was increased by 33 and 24 % in 1978/79
and 1979/80, respectively, compared with the control
when seeds were irradiated at 5 and 2.5 Kr.!,:doses.
On the other hand, s~d yield was reduced by 14
and 29 % in the two successive B6asons as a result of
treating seeds with the highest doses (70 aDd 80 Kr.)
straw yield was increased by 18 and 12 ” in 1978/79
and 1979/80 seasons ·at irradiation doses of 15 and 7.5
Er., respectively.
12- Radiation treatments at lower doses increased protein
content in stems and leaves of the thre’6 cuts of ”iV1eskawi”
cultivar. Such increase reached the le’~el of significance
in c lover stems of the third cut. in thj~ first e~.rimental
season.
13- Gamma rB3 doses generally increased protein content
In stems and leaves of ”Falll” plantl; of the first cut.
Such increase was beyond the level of s:i.gnificance.
14-0 Some morphological mutations, such as an increase in
the number of leaflets/leaf, were ob1~aiDedin ’’Meskawi”
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cultivar. Tb3 number of leaflets/leaf.reached 4, 5 and
6. The dose of 7.5 Kr. induced the highest percentage
vf mutated plants.
15- In I1Fahltl cultivSI’ the morpho Iog LcaL mutations included
increase Ln number of leaflets/l,eaf and induction
of basic branching after obtaining the first cut.
The highest percentages of mutated ”Fabl” plants were
obtained at 7.5 Kr.l”dose.