الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 116 |  |  |
| | | from | 116 | | |
Abstract
-S.UM-MAR-Y~
Four field experiments were oarried out to study
yield components and lint properties of some cotton culti-
Yara- Tbe four Egyptian cotton genotypes namely; Giza 80,
Giza 75, Giza 66 and Denders and the two Upland cotton genotype
s, namely; Monaire 220 and Stoneville 213 were grown
in two different plant1ng dates, i-e., last week of March
and Mayfor 1981 and 1982 seaSODS at Giza Bxperimental Research
station~ A randamized complete block des~n With
six replications vas used. fbe results obtained could be
summarized as follows I
1- The effect of ;elantiM date an~ genotypes on the yield
!ffid its components J
1- Tbe yield:
Tbe seed cotton and I1Dt yield were almost increased
by early planti.ng~ Genotypes also differed Significantly.
aesult8 indicated that American genotypes almost e%ce~d.d
the Egyptian genotypes in tbe amount of seed cotton and lint
Yiel~. Mcnaire 220 produced more seed cottOD aDd l1at )fie]1
thaD StoneVille 213. Moreover, Giza 80 vas tbe h~hest
yielding variety followed by Deodera, Giza 66 and Giza 75-
~--~---- --- -- - - ~
- 99 -
2- Boll we;gbt and number of bolls J
A- Boll wei8ht of the Egyptian genotypes vas hea-
Vier in early than late planting. However, results of
the two American genotypes shoved that planting date
failed to affected boll weight. Ddfferenoea due to genotypes
were significant and the two Amerioan genotypes produced
heavier boll weight than tbeir Egyptian counter _
pans. While, GiZa 80 gave bea” ier bolls than Deodera and
Giza 66.
B- The number of B/.2 and B/P almost decreased as
planting date was delayed. Genotypes also bebaved differently
Bod Dendera produoed greater ’DUilber tban ~rioan
an and Bgypt1ao genotypes. However, GiZa 75 and~the two
American genotypes al.most shoved tbe lowest values of nuaber
at B/.2 and B / P.
3- Lint percentages tended to increase slightly in early
planting. Genotype differences were apparent~ For instanee,
the Merican genotypes and Giza 80 variety vere 81-
.ost tbe highest in 11nt peroentage, whereas, Dendera variety
sbowed the loweat value.
4- Buaber ot siB mereaaed as boll weight increased.
On the other band, aignifi.eaot differences are also reported
among «enotypes ADd tbe two American genotypes pve relatively
acre siB tbaa tbe1r Igypt1an oounterparts.
-- - 0 _
- 100 -
5- Seed index vas heavier in early pI Ellting than
late planting - Genotypes demonstrated significant differences
and the Egyptian cottons shoved heavier seed
iDdeDs than American genotypes-
6- Lint indeces were greater in early planting
than late ones. Significant differences are also manifested
among genotypes- The highest lint index value
was for Giza 80 and the lowest value was for Dendera-
7- Fiber fineness, expressed in hair weight or
micronaire units tended to inorease in early planting-
Hair veight differed significantly among genotypes With
the American cottons being coarser than their Bgyptian
counterparts_ The exception was Giza 80 which was coarser
as the Upland genotypes_ The finest cul tivars vas
Dendera- On the other hand, inconsistent differences in
micronsire units among genotypes were observed in both
seasons-
8- Fiber length &8 measured by meaD length or barrfall
le~tb showed no defin1te trend as s result of cbanging
planting date- Genotypes differed 8ignificantly and
tbe Bgyptian cottons were longer ’than ’tbe American genatypese
9- Yarn strengtb were almost increased by early
planting in tbe :rirst seascn- In tbe seoond season,
- 101 -
strength of Giza 75 and Giza 66 increased by early planting
date, bowever, yarn strengtb of Giza 80, Dendera and
the two American genotypes vas decreased. Genotypes differed
significantly and tbe Bgyptian genotypes were stronger
than tbe two American counterparts. Moreover, GiZa 75
Was relatively the strongest Bgyptian variety followed by
Giza 80, Dendera and Giza 66 in descending order.
11- gorrelation among cbaracters s
1- Correlation coefficients between lint yield and
its oollponents indicated presence of a bi,gbly sjgaificant
association between number of bolls and lint y1eld.
fbe correlation coefficients among lint yield and ~B,
LIs, FISt MLand Mia were considerably lower_
2- lumber of’ bolla almost sboved lower coett1cientss
With s/», L/s, FISt IlL and Mia values-
3- The correlation coefficients between siB and z/s,
Fls, ML and Mie vere almost relatively lower in Ilagnitu~.
4- Correlation coef’f’icient between LIs aDd ita co.-
ponants (XL and Mia) 1Ildicated tbat tbere wera highly 81gnif’icant
associatioas for aost genotypes.
5- F/s Vas al&ost correlated negatively With both
ML and )(io values_
- 103 -
not witb standing, tbe negatively correlation of F/S
with ML aDd Mic~ In addition these models are useful in
determining the yield components most susceptible to alteration-
Application of these 110 del in breeding programs
may result in yield improvement. The yield models
aforementioned consist of basic interwoven biological
entities- Alteration of these entities, without hazardous
ef’fects on lint properties, can result in improving
cot’ton 7181d.