الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The present investigation was undertaken at the Faculty
of Agriculture of Moshtohor (zagazig University Benha Branch)’
The objective of this investigation waS concerned with genetic and
cytological studies on Q~~21!:!~.!:!! spp found in Egypt COffi’p’8reao
n
wi th some e x o t i c S ~f l”OITlt.: Germany.’
Stu d~te 5 Inc 1u dec’ f0 u r sp eC 1t:: ~ 0 f the ge nus Oc not her a ,-;
i.e.jQ. !l.i.~~~~~~ v a r fiedled, Q. ~l~~~~ L. var. grandiflora,
Q. ~2~~~i[er!! renner and Q. £~~~~~~ jacy. Karyotype studies
were carried out on these species at the mitotic metaphase
stage. All species studied had the same chromosome basic numbcr
(x = 7) in the smoatic cell. These chromosomes were metacentric,
sub-mctacentric, acrocentric and subacrocentric.
The following characters were studi ed
1- Earliness. 2- Plant heLg~t
3- Number of fruits per plan t 4- ~~I!’bcr of seeds per f r u i t
5- Weight of seeds per plant 6- 1000- seeds we i.ght
R-e-s-u-l-t-s---s-h-o-we-d---t-h-a-t--
(A): Additive genetic variances were more important
than dominance in the inheritance of Earlines. Dominance
genetic variances were more important than additive in the
inheretance of p la n t height,and numbe r of fruit’! plant fn
the inheritance of weight seed per plant and weight of 100
seeds The add i t ive and dom ina n c e t y pes ) 0 f g e n e act ion.
were imp 0r tan tin the inher ita nceo f;:the sc .tr a its .
(B): The average degree of dominance showed over
complete dominance whil~
partial dominanc
number of f~uit/ pl&nt.
showed
showed
dominance for plant height Earl i ne ss
(C): The negative and positive alleles were
equally distributed among the pare~tal populations for most
of the studied characters.
(D): The dominant genes were in excess in the parents
in case of plant height and number of fruit/plant and weight
of seed/plant and weight of IOOO-seeds. The values
of narrow sense heritability in all characters indicated
that the traits were highly influenced by the genetic
factors. There were positive genotypic correlations between
earliness and plant height and weight of seed! plant and
we igh tor 1000 seed sand numbe r 0 f f ru it.S I plan 1. There were
positive genotypic correlation between plant height and the
number of seeds! fruit.
Pi rst: Mi totic behaviour: studies included the
: I
Kar, otype and Ka~~)otype analys i s for four parent s 3 •
The following description summariz~ the characteristics
of the studied material
1- o. nissensis: 2n14. The average total length of
the hoploid complement in the five cells studied
was 29.10 + 0.41~. The mean length of the chromosemes
ranged from 0.95 to 5.84 p. The idiogram showed
that the 6th and 7th chromosomes were subacrocentric.
2- Q: biennis: 2n= 14. The average total length of the
haploid complement was 25.45 + 0.12 p. The mean length
of the chromosomes ranged from 1.25 to 7.06 p. The
idiogram showed that the 3!~ chromosome was acrocentic
with a small satellite attachl~d_ to its short arm.
3- o. coronifera: 2n= 14. The average total length of the
haploid complement was 30.22 + 0.06 p. The mean length
of the chromosomes ranged from 2.06 to The idio
gram showed that the 6th chromosome was subacrocentric.
4- o. odorata: 2n= 14. The average length of the haploid
complement was 19.00 + 0.08 p. The mean length of the
chr~osomes ranged from 1.51 to 4.49 p. The idiogram
showed that the 5!~, 6th and 7th chromosomes were subacrocentric.
Second: Miotic behaviour’ These studies included
the a b nor rnalit ies 0 f par e n tie san d the hy brid s P r0 ducE: c b ’f
d ia Ll e crosses, it. was :not’ic’ed that ther,e are~some c@s~eS
o f rin g s • and zig zag e w hie 11 : rnayin d icat e the v reS en ce ’ 0 f
c e r t ~ n .Ch r ono sane tr arr s:10 ea tl ons ,
In these studies the pollen grain mother cells were
examined in the stage of metaphase two (diakinases). ~he
StudY showed the following: r: l h.1<;:
a- ’fhc chromosomes appeared as circles consisting of four
five or sex chromosomes.
b- There were group conststing of two or three or four
five chromosomes in a zigzag shape.
c- There were chromosomes in star shape or a linear shape
or in bivalents.
e-
There were obend rings of chromosomes.
There were br idges chromosomes, and 1_~_gLn_g chromosomes
ins orne cas e s 0 f par en t e san d h Y b rid s . W nic h mt:\ ’/ in d i.cat e
dthe
Pi’G’>~ ;le,~ )f some acrocentric
from t r.a n s 10 c t ion s •
3) POll~n grain viability was high
in some hybrids
and low in others this strility also,
i
could be a”t r i bu t e dhet e r 0 z.y’-gou·s
t 0 c eft a inc h r orno s om a 1 abe r rat ion sin c led i ng
tranlocation