الفهرس 
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Abstract
’To study the effect of different levels of diluted sea water
on growth characters, chemical components and yield of cotton
plant, Giza 45 and Giza 81 varieties were grown in pot
experiments during the years 1987 and 1988. conducted in the
greenhouse at the Agricultural Experimental Station in Giza •
The soil was obtained from Giza governorate and 40 kg clay loam
soil was used in each pot • Salinity levels of diluted sea
water were O(So). 10000(Sl) ,15000(S2) and 30000(33) ppm.
Five growth periods were used; PI ’ P2 ’ P3 ’ P4 ’ P5 at
20-48 , 49-71 • 72-94 , 95-117 and 118-140 days after planting,
respectively, after growth period, it was irrigated with
tap water •
Vegetative growth characteristics were recorded as cotton
plant height and leaf number after each growth period , and
leaf area, as well as plant dry weight and chemical components
were measured at 48 (Gl) , 94 (G2) and 140 (G
3
) days after
planting • Daily notes for flowers numbers and flowering rate
per week were recorded • Cotton boll production as number,
weight and lint yield were mea~~red at G
3
•
The obtained results could be summarized as follows;
Pl~~t growth characters : -------------------------
00 Diluted sea water at S3 decreased plant height, leaf number
and leaf area more than S2 and Sl •
•• Cotton variety Giza 81 was affected with all salinity levels
more than Giza 45 specially in leaf number •
•• The first growth period was superior for decreas1.ng plant
height, leaf number and leaf area, and the ascending order
of the accumulation decreasing was PI / P2 < P3 < P4 < P5 •
•• Fit equation among linear, logarithmic ,exponenatial and
power regression equations for plant height, leaf number and
leaf area to every gr owt.hperiod was power regression equation
(Y=ax b ).
Chemical components :
•• Nitrogen, phosphorus and potassium absorbed by cotton plant
variety of Giza 45 al all stages ,’ere less than those taken up
by Giza 81 • Giza 81 ’,’:amsor’eaffected v..l th saline wet er,
salinity levels S2 and S3 Vleremore serious for the tested
cotton varieties than Sl •
•• Nitrogen, phosphorus and potassium content measured at Gl
were prono1L~ced affected compared with the control •
•• Nitrogen , phosphorus and potassium content measured at G2
were more affected at PI than other growth periods •
• 0 Nitrogen, phosphorus and potassium content measured at G3,
were more affected at P3 than the other gr-owth periods.
The ascending order v.a s P3( P2 ( PI < P4 (” P5 •
•• The two tested cotton varieties took up the same amount of
sodium, whereas, the logically highly sodium content was
noticed under S3 and S2 more than under Sl • The highly sodium
absorped Vias at P3 and the descending order was P3) P4 > P5 > <,
P2 / PI •
Cotton yield : --------------
•• Though Giza 81 yielded dry weight more than Giza 45, the relative
dry weights of Giza 81 was less than Giza 45 under Sl and S2 •
•• The relative decrease was high at Gl under 82 and low
at GJ under 81 •
•• 8J level decreased dry weights of the tested varieties more
than 81 level •
•• Dry weight measured at G2 under PI was the most adversely
affected than those of P2 and PJ •
•• Dry weight measured at GJ under PJ was more decreased than
other gr-owth periods, while the ascending order under 81 was
P3 ” P2 .’ PI’ P4 ’ P5 ,the ascending order under 82
and 83 was PI \ P2 ’ P3 ’-,P4 -; P5 •
•• Flowers number per plant of Giza 45 were more than Giza 81 •
•• The higher the salinity level, the more decrease in flower
number per plant. The low salinity levels (51) slightly
stimulated flowering •
•• The two tested varieties under PI were more affected in their
flower number per plant than other growth periods • The
descending order for the two salinity levels, was PI’; P ”- 2/
,
PJ / P4 •
•• All growth periods accelarated flowering in Giza 45 but sane
growth periods did that in Giza 81 •
•• Fit equation among linear, logarithmic, exponenatial and
power regression equations for cumulative number per plant
to every growth period was power regression equation
( Y = a xb) •
•• Boll retention in Giza 45 was more than in Giza 81 • Salinity
levels (81 and 82) affected on boll retention for the tested
cotton varieties, where, 82 has decreased boll retention more
than 82, •
•• Boll retention of cotton plant at PJ was the most affected
under 81, while at PI was the most affected under 82 and 8
The less affected one was P5 under the three tested salinity
levels •
•• Lint yield of Giza 45 was higher than that of Giza 81 • While
the higher lint yield of Giza 45 was the more decreased by
salinity level. S2 decreased lint yield more than Sl • The
ascending order under Sl was P3 <. P2 \ PI’ P4 <’ P5 ’
while under S2 it was P2 ( PI < P3 ( P4 < P5• This
means that PI and P2 were more or less the same in reducing
lint yield, while P5 represents the least effect •
Relationship of soil soluble salts with plant chemical components -----------------------------------------------------------------
and yields :
------------
A •• Soil soluble salts and reactions: ..................................
Considerable amounts of total soluble salts in the ~oil at
every growth period was found. The increasing of salinity
accumulation in the soil was accompanied with a decreasing
soil pH, that was slight between 81 and 82 • The change in
soil pH values under salinity was wi thin 0.6 uni t of pH •
B •• S.o.i.l..s.o.l.u.b.l.e..s.a.l.t.s..a.n.d..p.l.a.n.t..c.h.e.m.i.c.a.l..c.o.m.p.o.n.e.n.t.s.:..
Simple and multiple regression cleared that Nand P content
were negatively affected with soil soluble salt at all
regression relations, but K , Ca and Mg are positively
affected with soil soluble salts at early growth periods
(PI and P2) and negatively affected at later ones (P
and P5) • Sodium absorbed by cotton plant reveals positive
response at early growth periods.
S.o.i.l..s.a.l.i.n.i.t.y..a.n.d..c.o.t.t.o.n..y.i.e.l.d.:..
• • • Simple and multiple regression reveal that soil salinity at
PI severely affected dry weight either than measured after
PI or after P
3
, ?ut no effect on that measured after P5 •
Soil salinity at P2 had little effect on dry weight either
that measured after P3 or after P5, while soil salinity at
P
3
was in the opposite trend. The mUltiple regression
equation. is ;
• •• Soil salinity at the five growth periods decreased boll number
per plant and the contribution percent of PI’ P2 ’ P3 and P4
were 22.35 , 10.74 , 55.90 and 10.74 % but P5 contributed in
increasing boll number with negligible percent 0.27 % • The
mUltiple regression equation is ;
••• Multiple regression revealed that lint yield was affected by
soil salinity at growth period. The contribution percent of
soil salinity on decreasing lint yield were 2.04 , 10.67 ,
73.53 , 3.26 and 10.50 % at the five growth periods,
respectively • The mUltiple regression equation is ;
The effect of salinity on growth characters was more
pronounced at the earlier growth periods while its effect on
nutrient content, dry weight and boll retention was noticed at
medium growth periods •