الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
1. ~e present investigations represent an attempt
to study the genetic behaviour at the .reaction to Fusarium
w:Ut. as well as some other qualitative and quantitative
eharaoters in some Tomato orosses grO\Vnin the three
suooess1ve years (1964,1965,1966).
2. The study was based on the data of’ F
1
, F
2
and
Bel progenies of fourteen orosses including seven Varieties
of tomatoes; Red Cherrr, San Marzano, Pearl Harbor,
Ame.r1oan. Genome, Pearson 107 and Orange.
3. !Z!heinbentanoe of Fusarium wilt was studied
in eight crosses 1coluding the resistant varieti.es Red
Cherry. San Marzano and Amerioan. The F
plants showed
dom1nanoe at resis tanee in all orosses including tim
variety AmeZ!ican. and dominanoe of susoeptibility in
crosaes 1acluding the varieties Red Cherry and San Marzano.
The F2 and Bel generations showed that this character
was controlled by four dominant genes for resistanoe and
two domioant gsnes for susceptibility. The genes suggested
for ra sistanoe were (R) in the variety American. and was
epistatic to gene (81) for susoeptibility in Orangetgene(R
in Red Cber;rJ and the two ·comp~emanta.;eygene s ( ~ ~ R.5 )
for ~sistance in San Marzano, which we~ hypostatic to
ei ther genes (81 or 82 ) for susoeptibil.ity carried by
the varieties Orange aod Pearson 107. The recessive
@Bues ( r. r1• r2 t 81 ’ ’82 ) for susoeptibility wexe
carried by Pear~ Harbor.
4. The genetic behaviour of fruit shape was studied
as a qualitative eharaoter in ten crosses inoluding three
fruit shapes; roundish oblate, round, and. oval. The F1
plants showed the domi.nanoeof roundish oblate over oval
shape. It appeared :from the F2 and baokorosses segregations
that fNit shape chD.moter was governed by three
pairs of genes, where gene (E) oont:roJJac1 equatorial
expansion of fruit I (P) polar expansion, and ( Lc) few
10cule nwnber. and these genes interacted together to
give di.fferent fruit shapes. The recessive gene ( 10 )
.for many looule s modified frui t shape to be oblate when
present with either genes ( E orP ). The round fruit
shape appeared in genotfl)es (E P 10 ) as i.n the varie ty
.Amerlcan or (e p 10 ) as in the varia tY’Oranget the
roundish oblate sbape was developed in the presence of
the three dominant genes (E P La) as in Red Cherry and
Genomeor in the presence of two dominant genes (E La P )
as in Pearl Harbor and Pearson. 1.07. The oval f.ru1 t shape
was fouad in the presence of tiwo dominant genes ( e P La)
as in the variety San Mo.rzanf”.
5. Assooiation studies between :fruit shape and number
of locules per fruit showed significant associations in
five orosses. These associations might be probably due to
the presenoe of a linkage between one o;fiJthegene or
genes for Looul.e number and one of the froit shape genes,
being on the same ohromosome.
6. The iaheri banoe of fruit colour was studied in
eleven orosses iooluding red and orange fruited varieties.
Red flesh oolour showed to be dominant to orange .flesh
colour in Fl- It appeared from F2 and BOl progenies
that this charaoter was controlled by five pairs of genes ,
where the two oo~J..ementary genes ( R1 , ~ ) for red flesh
oolour located in the variet)’ .American and were epistatic
over gene (T) for orange flesh colour in the variety
orange • The f.1JP nes ( R3 ) in Genone, (R
4
and R
5
) in
Pearl Harbor, we.re all duplicate gs nea :for red f.ruit flesh
oolour epistatioto gene (T) for orange flesh colour.
The reoessive alleles for all these genes caused yellow
fle sh colour.
7. PZ’Ui.t size showed to be quanti ta tively lnheri ted
character in eight orosses. The F1 plants were intermediate
between pa.renal fruit sizes, showing partial. dominance
at small frUit size. The F2 distribution covered
the ranges of both panencs or beyond the range o£ the largo
fmited parent. The number of genes for fruit si.ze varied
greatl}” fJ:’Om (1”:’12)pairs of genes with multiplioative
gene aotd.on, However, this value reaohed (25-33) pairs
of genes in the cross Red Cherry x Genome. Heritability
values were high in all cases ronging from (62.12% _
96.91% ) t showing e:ff’eotiveness of selection :for fJ:\lit
weight.
8. In the crosses belonging to the large x large
.fruit group inolud1ng the two crosses, San Marzano x
(Pearl Harbor and Genome), there was a oha.raoter1stic
shift in fruit s1.ze. The meanfruit weight of F
plants
was very muchlowQr than the comparatively am.all er fruited
parent. This pbenomenonoontinued in F2 of the cross
San Marzano x Pearl Harbor onJ.y. This phenomenon was
suggested to be reJ.ated either to negative heterosis or
to effeot of acoumulation of dominant genes for small
fmited size existed in both large fmited parents.
9. Plant height was lnheri ted as a quanti.tative
character in two orosses. The F1 plants .represented the
dom1nanoe Of long stem accompanied by heterosis in the
oross Pearl Harbor-x Orange and showed partial dominance
:for long stalked plant in the CroBS American x San Marzano.
Number~ genes governing plant height showed to be
limited ranging from (1-2) pairs. The heritability for
th1s ohamoter was high. enough ( ranging from 62.95% _
92.89%) to indicate the effectivenoss of selection for
this oha.raoter.
10. The inheritance of ascorbic acid content in
fruits was studied in the arOSB .Pearson 107 x San Marzano.
The F1 plant showed intermedia.te values between parents t
and F2 plants showed partial dominance (]f high vitamin C
in the variety Pearson 107. Simple monogenic inheritance.
was observed in F2 distribution with some modifiers having
additive effeot. The heritability far this cll.aracter was
very high ranging ( 92.71% .;. 93.43%)t indicating effectiveness
0:£ seleotion for high vitamin C contents.