fiber maturity measured by a Micronaire instru- ment, and iii flat bundle strength expressed in
terms of strength weight ratio ‘s.w.r.’ measured by the Pressley index according to Annual Book
of ASTM Standards, D 1447-77, D 1448-79, and D 1445-75, respectively, 1979. Results were ana-
lyzed as a factorial experiment Snedecor and Cochran, 1980.
3. Results
3
.
1
. Seed 6iability and seedling 6igour Seed viability germination percentage and
seedling vigour lengths of hypocotyl, radical and entire seedling; as well as seedling fresh weight
significantly exceeded the seedling of the control 24 h in water only when the seeds were soaked
for 24 h in kinetin solution at concentrations varying between 0.5 and 10.0 mg l
− 1
Table 1. Soaking seeds in kinetin solution of 0.25 mg l
− 1
or more had a significant effect on radicle and seedling lengths compared to the untreated con-
trol; generally, 10 mg l
− 1
induced great significant increments than 0.25 mg l
− 1
.
3
.
2
. Yield components
3
.
2
.
1
. Number of opened bolls per plant Kinetin at concentrations over 0.25 mg l
− 1
increased the number of opened bolls per plant in both seasons, as compared with the control Table
2. The 5 mg l
− 1
treatment produced the highest number of opened bollsplant. The kinetin appli-
cation methods, i.e. foliar application B and a combination of soaking and foliar applications
C increased the number of opened bolls per plant over seed soaking in both seasons. This
increase was significant for application methods B and C in 1993 and for application method C in
1994. The number of opened bolls per plant was numerically the greatest from the application
method C.
3
.
2
.
2
. Boll weight Boll weight was increased by the different con-
centration treatments of kinetin over the un- treated control in the two seasons Table 2. The
increases were significant for the kinetin concen- trations ranging from 0.5 to 10.0 mg l
− 1
in 1993 and from 1.0 to 10.0 mg l
− 1
in 1994. The 5.0 mg l
− 1
concentration produced the largest boll weight. Kinetin application methods B or C in-
creased the boll weight as compared with method A in both seasons. This increase was significant
with method C in 1993, and methods B and C in 1994, with no statistically significant differences
between them. Method C produced the highest boll weight.
3
.
2
.
3
. Lint percentage Kinetin did not cause any significant changes in
lint percentage in either season despite a slight numerical trend for an increase in lint percentage
compared with the untreated control. Application method B slightly increase lint percentage over
methods A and C in 1994.
3
.
2
.
4
. Seed index Kinetin applications increased seed index in
both seasons, as compared with the control Table 2. The increase was significant for all concentra-
tions in 1993, and for 0.50 – 10.0 mg l
− 1
in 1994. The largest increase in the seed index was found
in the case of 5.0 mg l
− 1
concentration, followed by 10.0 mg l
− 1
. Method C was superior to method A in both seasons, while method B was
better only in 1994.
3
.
2
.
5
. Lint index Lint index significantly increased with all
kinetin concentrations in both seasons Table 2; the differences among rates were not significant.
The methods B and C proved superior to method A in both seasons.
It is worthy to mention that the effects of the interaction between kinetin concentrations and
application method on all yield component char- acters were statistically insignificant.
3
.
3
. Yield Seed cotton yield per plant, as well as seed
cotton and lint yields per plot, were significantly increased with the application of kinetin up to
Z .M
. Sawan
et al
. En
6 ironmental
and Experimental
Botany
44 2000
59 –
68
63 Table 1
Effect of soaking cottonseeds in solutions of different kinetin concentrations for 24 h before planting on seed viability and seedling vigour Kinetin concentration
Seedling length Seedling fresh weight g10 seedlings
Radical length Germination percentage
Hypocotyl length cm
cm cm
mg l
− 1
Actual Arc sine
a
13.0 9 0.28 6.43 9 0.237
8.26 9 0.160 4.74 9 0.133
0.00 61.4 9 0.88
77.0 9 1.29
b
Control 8.95 9 0.115
13.9 9 0.17 6.56 9 0.092
78.5 9 1.70 62.4 9 1.18
0.25 4.94 9 0.668
5.12 9 0.098 9.10 9 0.092
14.2 9 0.18 6.81 9 0.072
82.5 9 0.95 0.50
65.3 9 0.71 14.6 9 0.38
6.79 9 0.049 9.19 9 0.258
85.5 9 0.95 5.40 9 0.124
67.7 9 0.79 1.00
9.15 9 0.188 14.7 9 0.31
7.07 9 0.050 86.0 9 1.82
68.2 9 1.51 5.54 9 0.131
5.00 5.41 9 0.119
9.08 9 0.163 14.5 9 0.27
7.21 9 0.173 10.00
87.0 9 1.29 68.9 9 1.10
0.159 0.239
0.39 0.166
1.98 SE
c
1.53 0.83
0.355 0.510
0.340 4.22
3.28 LSD
d a
Arc sine = Angles corresponding to percentage.
b
9 Standard error of the respective averages.
c
SE = Standard error for the differences among averages.
d
LSD = The least significant difference test was utilized to identify significant differences between treatment averages at 5 level.
Table 2 Effect of kinetin concentration and methods of application on yield components of cotton
a
Kinetin application method Kinetin concentration mg l
− 1
C Average
A B
B C
Average A
1994 1993
Number of opened bollsplant 0.00 control
12.9 12.8
12.8 13.2
13.2 13.2
13.2 12.9
13.4 0.25
13.1 12.9
13.4 13.4
13.7 13.5
13.0 13.8
13.4 13.6
13.9 13.4
14.2 0.50
13.9 13.0
13.5 13.0
13.9 13.4
13.5 14.0
14.5 14.0
1.00 14.1
13.6 13.8
14.2 5.00
14.7 13.2
14.2 13.5
13.8 13.6
13.6 14.3
13.8 14.5
13.2 14.2
10.00 13.4
13.0 13.6
13.5 13.8
14.1 Average
SE kinetin concentration 0.22
0.27 0.19
0.16 SE application method
SE for interaction 0.39
0.46 Boll weight
g 2.26
2.28 2.27
2.27 2.24
2.24 2.25
2.24 0.00 control
2.36 2.33
2.25 2.32
0.25 2.30
2.31 2.29
2.32 2.40
2.36 2.24
2.35 2.35
2.36 2.33
2.32 0.50
2.38 2.33
2.41 2.37
2.25 2.35
2.43 2.34
1.00 2.42
2.39 2.31
2.36 2.51
2.39 5.00
2.33 2.42
2.43 2.39
2.26 2.33
2.39 2.44
10.00 2.36
2.34 2.38
2.26 Average
2.33 2.32
2.38 2.35
0.046 SE kinetin concentration
0.032 0.033
0.023 SE application method
SE for interaction 0.080
0.056 Lint percentage
34.0 34.0
33.3 0.00 control
33.7 34.1
33.5 33.5
34.0 0.25
34.1 34.2
34.1 33.4
33.9 33.5
33.6 34.0
0.50 34.3
34.2 34.4
33.3 33.7
33.5 33.5
34.6 34.2
34.3 33.3
33.9 34.7
33.4 1.00
33.5 34.1
34.7 34.2
34.2 34.4
33.4 33.7
33.5 33.6
5.00 34.2
34.3 33.5
33.8 33.6
33.6 10.00
34.2 34.3
34.2 33.4
33.8 33.5
34.4 34.1
Average 0.20
0.23 SE kinetin concentration
0.16 0.14
SE application method 0.34
SE for interaction 0.40
Seed index g
9.9 9.9
0.00 control 9.8
9.9 9.8
9.8 9.8
9.9 10.2
10.1 9.8
10.0 10.1
10.0 0.25
9.9 10.0
10.1 10.0
10.2 10.1
9.8 10.0
10.0 10.0
0.50 10.2
10.1 9.9
10.0 1.00
10.0 10.0
10.0 10.1
10.2 10.2
9.9 10.0
10.2 10.1
10.0 10.0
5.00 10.2
10.0 10.2
10.1 9.9
10.0 10.1
10.0 10.00
Average 10.1
10.2 9.9
10.0 10.0
10.0 0.06
SE kinetin concentration 0.07
0.04 0.05
SE application method SE for interaction
0.11 0.13
Lint index g
5.13 5.11
5.10 5.11
4.90 5.00
4.94 4.95
0.00 control 5.16
5.24 5.27
5.22 4.92
5.12 5.03
5.02 0.25
5.32 5.29
4.91 5.09
5.36 5.05
0.50 5.02
5.21 5.31
5.30 4.93
5.12 5.04
5.03 1.00
5.20 5.38
5.33 5.31
4.98 5.11
5.39 5.10
5.00 5.06
5.21 5.30
5.23 5.32
5.28 4.99
5.12 5.09
5.07 10.00
5.27 4.94
Average 5.09
5.19 5.04
5.30 0.035
0.051 SE kinetin concentration
0.025 0.036
SE application method SE for interaction
0.089 0.061
Table 3 Effect of kinetin concentration and methods of application on cotton yield
a
Kinetin application method Kinetin concentration mg l
− 1
A B
C Average
A B
C Average
1993 1994
Seed cotton yield gplant
29.1 29.2
0.00 control 29.2
29.1 29.6
29.7 29.7
29.7 30.2
30.6 0.25
30.6 29.9
30.2 31.0
31.4 30.9
31.6 33.1
31.6 30.5
30.2 32.5
0.50 33.4
32.1 32.1
33.4 31.9
1.00 30.4
30.3 32.8
35.1 32.8
32.7 34.1
32.5 31.8
30.9 33.6
5.00 36.7
34.0 30.8
10.00 32.9
33.6 32.5
30.8 33.9
35.4 33.4
Average 30.2
31.4 32.5
30.5 32.2
33.6 0.53
0.67 SE kinetin concentration
0.47 SE application method
0.38 SE for interaction
1.16 0.93
Seed cotton yield kgplot
3.30 3.30
3.30 0.00 control
3.38 3.29
3.38 3.39
3.38 3.42
3.60 3.47
0.25 3.44
3.38 3.55
3.58 3.52
3.51 3.68
3.52 3.47
3.36 3.71
0.50 3.79
3.66 3.43
1.00 3.63
3.77 3.61
3.47 3.74
3.99 3.73
3.76 3.88
3.73 3.62
3.55 3.82
5.00 4.18
3.87 3.50
10.00 3.74
3.86 3.70
3.51 3.86
4.02 3.80
Average 3.42
3.56 3.68
3.48 3.68
3.83 0.063
0.081 SE kinetin concentration
0.057 SE application method
0.044 SE for interaction
0.141 0.109
Lint yield kgplot
1.12 1.12
1.12 0.00 control
1.13 1.12
1.14 1.14
1.13 1.17
1.23 1.18
0.25 1.15
1.15 1.20
1.20 1.18
1.21 1.26
1.21 1.16
1.15 1.25
0.50 1.27
1.23 1.00
1.26 1.17
1.29 1.24
1.16 1.27
1.34 1.25
1.30 1.33
1.28 1.21
1.21 1.29
5.00 1.40
1.30 1.29
1.32 1.27
1.17 1.31
1.35 10.00
1.28 1.20
1.23 1.26
1.16 1.24
1.28 1.17
Average 0.023
0.027 SE kinetin concentration
SE application method 0.019
0.016 0.040
0.047 SE for interaction
a
SE = Standard error.
10.0 mg l
− 1
in both seasons Table 3. The highest increase in cotton yield was achieved at
5.0 mg l
− 1
, followed by 10.0 mg l
− 1
. These two kinetin concentrations significantly increased the
seed cotton yield per plant and per plot compared with the 0.25 mg l
− 1
in both years, and, along with the 1.0 mg l
− 1
treatment also produced more lint yield per plot than 0.25 mg l
− 1
. Application method B or C significantly increased the cotton
yield, as compared with method A in both sea- sons, without any significant differences between
method B or C. The highest numerical increase was obtained from method C.
3
.
4
. Yield earliness Neither kinetin concentrations nor kinetin ap-
plication methods caused significant differences in yield earliness of yield obtained in the first
picking in either season. However, kinetin con-
centrations ranging from 0.25 to 5.0 mg l
− 1
and application methods A and C resulted in a slight
numerical reduction in yield earliness.
3
.
5
. Fiber properties Kinetin application did not significantly affect
fiber length parameters 2.5 and 12.5 span lengths and uniformity ratio, micronaire reading or flat
bundle strength in either season, with only one exception, where micronaire reading increased
compared with the untreated control in 1994. This increase in micronaire reading was significant when
applying concentrations of kinetin ranging from 0.5 to 10.0 mg l
− 1
. The mean values of these characters tended to slightly increase by applying kinetin at
different concentrations when compared with the control. The kinetin application methods did not
affect fiber properties in either season, with two exceptions where fiber 12.5 span length and flat
bundle strength increased when applying method B as compared with method A. Fiber 2.5 and 12.5
span lengths, micronaire reading and flat bundle strength tended to increased slightly by using
application method B, followed by application method C, compared with application method A,
while length uniformity ratio did not follow a definite trend.
3
.
6
. Interactions Interactions were noted between kinetin concen-
trations and kinetin application methods regarding their effects on seed cotton yield per plant and seed
cotton and lint yields per plot in 1994 Table 3, but not on other measured characters. Favourable
effects for 5.0 mg l
− 1
kinetin concentrations on seed cotton yield per plant and seed cotton and lint
yield per plot, were more obvious when kinetin application method C was used.
4. Discussion
