Relative effectiveness of pedigree and recurrent selection in cotton
Abd El-Salam,M.E, B.M.Ramadan and Y.M.EL Mansy
Cotton Research Institute, Agricultural Research Center, Giza, Egypt
ABSTRACT
Effectiveness of the breeding procedures aiming to covlue new strains with better yield
and other traits. Thus, hybridization followed by pedigree selection was and still breeding
procedure that all Egyptian cotton varieties. But using recurrent breeding programs are useful
for cotton breeding programs. Some best lines some unfavorable alleles field and new crosses
necessary .On the other hand, intercrossing plays a very important role when variance is non
additive. Therefore, the main objective of this study to compare pedigree selection and
recurrent selection within the cotton population Giza 70 x Suvin. The hybrids and F4 families
evaluated with original parents were planted in a randomized complete block design. The
results reported that mean performance of hybrids increased compared with F 4 generation
and base population (F2) for yield cotton. There are differences between the correlation for (
F2, hybrids and F4 families) of direction and significant due to different selection criteria and
random intermating have created substantial amount of genetic variability . The observed gain
for lint yield was high in recurrent selection compared with the F 4 families. Therefore, two
hybrids which have high yield (higher than Giza 70 ) and similarity in fiber quality with it.
Therefore, random intermating between F3 fore one or more cycle give the amount of
variability help the breeder to improve the traits and would dissipate. Although, dominance
effect in these hybrids, but it helps to increase of favorable alleles in the next generation by
selection and crossed between the best plants and best hybrids.
INTRODUCTION
Effectiveness of the breeding procedures aiming to covlue new strains with better yield
and fiber characters. Thus, hybridization followed by pedigree selection was and still the
breeding procedure that yield all Egyptian cotton varieties grown commercially ( Salama et
al., 1992) .
Recurrent breeding programs have been started in self fertilizing crops and the best
lines some unfavorable alleles are fixed and new crosses are necessary and intercrossing plays
a very important role when variance is non-additive. Meredith and Bridge 1971, conducted a
study to determine if the negative genetic associations frequently observed between yield and
fiber strength in cotton be reduced by random intermating. Also, the negative genetic
correlation between lint and fiber strength was decreased by intermating. Ali (1977) found
that magnitudes of correlation coefficient in cycle1. Selection tended to be lower compared
with estimates provided by the F5 families. El-Agamy and Yousef (1980) reported that the
pedigree lint method was more effective easier for improving quantitative. Opondo and
Patrak (1982) reported of using recurrent selection in each population to increase the
frequency of favourable genes so that the populations and population crosses are improved
with each selection cycle. Simith and Coyyle, 1997 additional generation of intermating
would be necessary to rule out pleiotropic effects since the negative association were not
totally broken but only reduced in degree when F1 population resulting from crossing
contrasting parents were compared, El-Mahdy,2001 found that recurrent selection for seed
cotton yield was better than pedigree selection in early and late sowing of two populations of
Egyptian cotton.
El-Lawendy 2003, found that the superiority of some hybrids in lint yield
over better parent in two populations and some hybrids were higher than selected parents for
lint percentage. No increase was found to be significant are better parents for lint percentage
and seed index of the three populations. However, Abd El-Salam, (2005) found that some
hybrid were superiority in lint yield, lint percentage and fiber length for the three populations
except for in population III if lint percentage no increase for lint percentage compared with
better parent (G.80
LP. 42%). El-Mahdy,2007 found that after two cycle of pedigree
selection the observed gain in seed cotton yield in percentage from the better parent in early
sowing data ranged from 16.9 to 56.%in population I and from 16.1 to 24%in population II
Therefore, the main objective of this study was to compare with pedigree selection and
recurrent selections within the cotton population (G.70 x Suvin) .
MATERIALS AND METHODS
The present study carried out at Sakha Agriculture Research Station during
2009, 2010 and 2011 seasons. The materials used in this study included one
population of cotton belonging to Gossypium barbadense L (Giza 70 x Suvin).
Breeding procedures and management of population . In the first season, The
F2 of the population with original parent were grown in non-replicated ridges 7.5
meters long and 0.65 meter wide . All plants were self pollinated and all plants were
chosen (selected) in the field and picked up separately and the total seed cotton yield /
plant was ginned to estimate. Lint percentage, boll weight and seed index. The
superior 20 plant for each trait were selected at 5 % selection intensity on trait level
only.
In the second year, selfed seeds of the selected progenies were evaluated. Each
progeny was grown in one row (7.5 meter). In flowering phase, pollen grains of all
flowers was collected ( two selfed flower for each family ) were mixed in Petri-dishes
before and used for pollination of all F3 families to produce the first cycle of
recurrent selection in (2010) and selfed seeds of the F3 families selected . The same
system was reported by Ali, 1977 Third year, the hybrids, selected, F4 generation with
original parents were planted in a randomized complete block design with three
replications.
Statistical and genetic analysis:
Estimation of phenotypic for F2, and F4 generation .
Estimation the phenotypic coefficients.
Phenotypic correlation ( rpij ) in F2 =
σ pij
√σ2 pi . σ2pj
Where :
σ pij = (F2) Covariance between characters I and j,
σ2 pi = (F2) Variance of the characters I and
σ2pj = (F2) Variance of the characters j.
Observed direct = (Xf-Xbp/Xbp)*100
Where :
xf = Mean of each family or hybrid
Xbp = Mean of the better parent
Recurrent selection
Selfed seeds of the all F3 progenies were crossed by mixed grain pollen of all F3
progenies. The hybrids for the population with original parents were planted in a randomized
complete block design with three replications in a similar manner of spacing as followed with
pedigree selection .
The studied traits were:
1. Seed cotton yield, g/plant.
2. Lint percentage, %.
3. Boll weight, g.
4. Seed index, g.
7. Micronaire reading
5. Lint index, g.
8. Fiber strength.
6. Fiber length, mm. 9. Uniformity ratio.
RESULTS AND DISCUSSIONS
Mean, rang and variance
The mean of F2, F4 and hybrids were cleared that in Table 1 and Figure 1,2,3.
The results reported that mean performance in hybrids was higher than F2 and F4 for
seed cotton yield, lint yield, seed index and lint index, while for lint percentage the
mean performance for three populations were nearly. But, on the other hand rang for
F2 (base population) was higher than other the two populations for all traits, these give
variability in F2. High variability in base population helps the breeder to improvement
of these traits by different selection methods. The increase of mean performance of
recurrent selection hybrids for all traits due to recombination. Although, dominance
effect in theses hybrids, but it help to increase of a favorable alleles in the next
generations by selection and crossed between the best plants and best hybrids.
Meredith and Bridge 1971, conducted a study to determine if the negative genetic
association frequently observed between yield and fiber strength in cotton could be
reduced by random intermating. Also, intermating would be necessary to rule out
pleiotropic effects, Simith and Coyle, 1997.
Table 1: Estimation of mean, phenotypic variance, rang and genetic coefficients of variation
PCV to three segregating generation of the pedigree and one cycle of recurrent selection
schemes for traits.
Para
meter
s
mean
SD
Var.
Min.
Max.
Skne
s
Basic population F2
Recurrent selection C1
Pedigree selection F4
S.CY
LY
LP
SI
LI
S.CY
LY
LP
SI
LI
S.CY
LY
LP
SI
LI
48.9
18.1
37.0
9.73
5.72
54.0
19.9
36.9
10.2
6.0
44.7
16.6
37.2
9.77
5.78
21.4
7.92
2.24
0.883
0.711
16.0
6.06
2.0
0.651
0.509
11.2
4.3
1.96
0.529
0.416
459.4
62.8
5.02
0.779
0.507
257.4
36.1
4.01
0.424
0.259
125.6
18.5
3.83
0.279
0.173
7.4
2.8
28.8
6.8
3.89
15.9
5.5
31.9
8.9
4.67
26.1
10.4
32.0
8.87
4.51
180.5
65.5
43.9
12.2
7.68
97.2
36.8
43.2
11.8
7.14
68.9
26.1
40.1
10.8
6.33
1.24
1.18
-0.34
-0.04
-0.27
0.667
0.587
-.0189
0.010
-.386
0.735
0.831
-.688
0.199
-0.916
GCV
38.3
39.1
5.01
7.3
10.1
20.7
20.9
3.9
4.9
4.9
21.6
22.7
4.8
4.5
5.79
PCV
43.8
43.8
6.06
9.07
12.5
26.5
26.9
4.9
6.5
7.0
25.1
25.9
5.3
5.4
7.25
When skeweness value is positive indicated that increase of plants (families)
which has low value comparing to the mean while negative clear that decrease of
plants (families). Most the values of the skeweness were some trend for the three
populations.
The information a bout the degree of association among any traits of cotton
under different breeding methods is of great importance in plant breeding programs
and are of importance to response to selection. Therefore, estimated the correlation
coefficients in F2 (base population), hybrids and pedigree selections are presented in
Table (3) . The correlation between seed index and lint percentage was negative and
significant for pedigree selection, but in recurrent selection was non significant. Also,
the correlation coefficient between boll weight and seed index changed from nonsignificant for pedigree and recurrent selection, respectively. These difference in the
correlation due to the changes the relationship by random intermating .
The Correlation between the selected traits ( seed cotton yield, lint yield, boll
weight, lint percentage and seed index) in base population (F2) was non-significant for
all traits except for seed cotton with lint yield. But, this relation changed in the
pedigree and recurrent selection of some traits. These differences between the
correlation may be due to different selection criteria and random intermating have
created substantial amount of genetic variability during generation of selection similar
results were reported by Singh et al., 1985 and McCarthy et al., 1996 and Abd ElSalam, 2005 , Singh et al., 1985, found that correlation coefficients in C1 and C2
cycles changed insignificance values from 0.57 in C1 cycle to 0.59 in C2 cycle. The
important of correlation for the breeder due to, if they are inversely associated if
desirable and undesirable genes are linked together, intermating would dissipate the
negative correlations as observed in our study and reported earlier by Meredith and
Bridge (1971). Also the results reported decreased genetic correlation in a cotton
population following several cycles of intercrossing suggesting that intercrossing
trends to break up initial linkage block following across between inbred lines.
TABLE 3.phenotypic correlation for all traits in F2,F4and C1.
BW
SCY
LY
LP%
SI
MIC
UN
F2
0.249
SCY F4
0.35
C1 0.014
F2 0.253*
0.99**
LY F4
0.306
0.979**
C1 -0.117 0.388**
F2
0.05
0.035
0.097
LP% F4 -0.262
-0.017
0.184
C1 -0.136
-0.119
0.86**
F2
0.214
0.045
0.031
-0.077
SI
F4
0.248
0.015
-0.089 -0.49**
C1 0.475** -0.002
-0.075
-0.076
F4
0.128
0.381*
0.317
-0.308 0.108
MIC
C1 0.032
-0.005
-0.053
0.059 -0.223
F4 -0.104
0.071
0.084
0.077
0.01
0.089
UN
C1 0.115
0.134
0.041
-0.02
0.11
-0.128
F4
0.154
0.082
0.044
-0.11
0.228
-0.219
-0.15
FL
C1 0.149
-0.017
0.038
0.056
0.14 -0.412** 0.23*
F4
0.007 -0.454** -0.468** -0.093 0.169 -0.587** -0.06
PL
C1 0.015
-0.069
-0.083
-0.052 0.111 -0.291* 0.094
Observed direct and correlated response for seed cotton yield measured in
percentage of the better parent after of pedigree and one cycle recurrent selection.
The results in Table 4. Six families significantly out yield over better parent of
recurrent selection, while two families were the higher than better parent for yield in
pedigree selection . The observed gain in seed cotton yield of the best six families
ranged from 81.1 to 51.2 , also ranged from 84.6% to 54.8 for lint yield, 1.16 to 9.41
for lint percentage, from seed index 9.90 to -1.98, and 13.5 to 9.3, for boll weight ( in
recurrent selection) . While, all hybrids showed decrease compare with Giza 70
(better original parent). Therefore, there are two hybrids (20 and 66) which have high
yield (higher than Giza 70) and similarity in fiber quality with it .
In pedigree selection families, two families were high yield. Also, the results
reported that the best five families ranged from 32.8 to 8.3, for lint yield, 38.7 to 17.2
for lint
Table 3.Observed direct and correlated response for seed cotton yield measured in percentage of
the better parent after of pedigree and one cycle recurrent selection.
FAM
LEIES
BW
SCY
LY LP%
SI
LI
MIC
UN
FL
PL
3
-5.52
73.6**
72.1** -3.60
6.93
0.0
0.00
1.87
-0.42
-0.49
6
13.54
64.9**
66.5** -1.96
-1.98
6.82
6.82 -0.96
-1.55
-4.41
13
2.40
68.4**
72.6** -0.35
3.96
13.6 13.64
0.28
-4.93
-9.80
20
-12.19
49.0**
54.8**
1.16
0.99
6.82
6.82
1.19
1.27
-2.94
66
-9.38
81.1**
84.6** -1.23
9.90
6.82
6.82 -0.40
3.24
-2.94
Pedigree selection
3
13
19
25
-4.156
-2.778
-10.06
-4.156
32.8**
19.9
8.29
32.0**
38.7**
32.4
17.2
35.5**
29
-6.250
22.9
20.2
1.331
7.530
5.290
0.038
4.747
-6.267
-12.21
-6.267
2.970
6.931
9.09
11.4
15.9
9.09
15.9
9.091
11.36
15.90
9.09
1.81
-0.45
-3.39
-0.79
2.817
-10.70
-7.32
-0.563
0.00
-10. 8
-11. 5
-7.84
15.90
1.13
0.563
-4.902
yield, 7.53 to -4.75 for lint percentage and same trend for fiber traits for
recurrent selection similar results reported by Shaheen et al., 2000 they found that a
comparison between Giza 45 and some of the best F3 families revealed that the better
yield ability in plants with similarity in fiber quality.
The previous results cleared that pedigree selection for lint yield were 20 38.2% above the better parent, while one cycle recurrent the six best hybrids exceeded
the better parent (81.1-49.1%).
Pedigree selection method:
The results), showed that a mean performance of seed cotton yield, three ,
eleven and thirteen families were high for lint yield, fiber length and fiber strength.
The mean performance of the five high of inters for each selection procedures are
presented for lint percentage, fiber length, fiber strength in Table5. Lint percentage
for recurrent selection ranged from 43.2 to 40.0while,in pedigree selection was 40.0 to
39.2 .For fiber length, ranged from 38.5 to36.6 mm and 36.7 to 35.7for recurrent and
pedigree selection respectively .But, the same trend founded of fiber strength .
Therefore, using of recurrent and intercrossing in cotton for increased the lint
percentage and fiber traits .Meredith and Bride 1973,came to a similar conclusion
that using a modified from of recurrent selection for increased lint percentage .
Therefore, random intermating between F3 for one or more cycle give the
amount of variability help the breeder to improve the traits and would dissipate the
negative correlation .
Table6 .Means of the high five families and hybrids for lint percent, fiber length and fiber
strength of F4 and C1.
F
20
23
13
14
2
BW
2.64
2.69
3.11
0.91
2.91
SCY
44.67
40.40
62.27
26.07
36.07
21
8
55
52
24
2.88
3.12
3.18
3.42
3.23
62.9
51.8
61.1
37.8
37.5
4
17
3
27
24
2.76
2.96
3.07
3.04
3.38
42.50
49.43
68.93
42.43
42.87
61
45
41
66
4
2.81
2.99
3.32
3.16
2.96
70.9
47.4
60.1
94
62.5
6
26
4
2
17
3.02
2.78
2.76
2.91
2.96
34.17
33.57
42.50
36.07
49.43
56
48
4
30
62
G.70
Suvin
bp
LSD..05
LSD.01
LSD.05 R
LSD.01 R
3.21
3.6
2.96
3.44
3.50
2.56
3.2
3.20
0.355
0.472
0.691
0.913
42.9
41.1
62.5
53.4
50.4
39.2
51.9
51.90
17.938
23.880
24.892
32.863
lint percent
LY
LP%
17.80
40.05
16.17
40.01
24.90
40.00
10.40
39.72
14.13
39.27
C1
27.2
43.215
20.9
40.373
24.9
40.246
15.1
40
15
39.962
Fiber length
15.43
36.40
18.20
37.02
26.07
37.70
15.47
36.57
16.33
38.10
C1
24.5
34.854
18.1
38.462
22.6
36.947
34.7
36.744
23.5
37.62
Fiber strength
12.07
35.51
12.40
37.12
15.43
36.40
14.13
39.27
18.20
37.02
16
13.6
23.5
20.2
18.6
14.5
18.8
18.80
6.574
8.752
9.415
12.430
37.213
32.908
37.62
38.555
36.991
37.20
36.2
37.20
0.822
1.094
3.056
4.034
F4
SI
9.00
9.40
8.87
9.60
9.73
LI
6.01
6.27
5.91
6.33
6.29
MIC
4.9
5.1
4.9
4.5
4.4
UN
89
87.1
87.9
89.7
88.6
FL
34.4
35.1
31.7
33.7
34.5
PL
9.5
9.3
9.1
10.1
11.3
9.05
9.4
10.6
10.3
9.5
F4
9.07
10.00
9.47
9.73
10.27
6.89
6.36
7.14
6.87
6.32
4.8
5
5.1
4.9
5.1
88.55
89.05
85.15
90.3
84.95
34.35
33.75
35.45
35.75
33.15
9.15
10.1
9.6
9.4
9.45
5.19
5.88
5.73
5.61
6.32
4.7
4.6
4.8
4.6
4.5
89.2
90.7
89.9
9
87.9
36.7
36.6
36.5
35.9
35.7
11.3
10.7
10.2
10.5
10.7
11.1
9.7
10
11.1
9.5
F4
10.50
9.60
9.07
9.73
10.00
C1
11.3
10.6
9.5
10.1
10.2
9.9
10.10
10.10
2.220
2.956
1.184
1.564
5.94
6.06
5.86
6.45
5.73
4.2
4.7
4.5
4.7
4.1
89.55
85.85
89.05
87.95
86.85
38.45
37.15
36.85
36.65
36.55
9.9
10.2
9.8
9.9
11.1
5.78
5.67
5.19
6.29
5.88
4.8
4.6
4.7
4.4
4.6
88.1
85.1
89.2
88.6
90.7
35.3
35.2
36.7
34.5
36.6
11.8
11.5
11.3
11.3
10.7
6.70
5.20
5.73
6.34
5.99
5.86
5.73
5.98
0.716
0.953
0.927
1.224
4.6
4.8
4.1
5.1
4.7
4.4
5.20
4.4
0.28
0.38
0.39
0.53
87.55
89.55
86.85
86.25
90.05
88.30
85.50
88.3
1.58
2.11
1.93
2.6
34.55
34.75
36.55
33.35
34.75
35.50
34.50
35.5
2.63
3.53
2.72
3.67
11.7
11.2
11.1
11.05
11
10.20
9.30
10.2
0.97
1.3
0.98
1.32
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‫الملخص العربي‬
‫كفاء ة انتخاب النسب واالنتخاب المتكرر فى القطن‬
‫ ياسر محمد المنسى‬-‫ بدير مصطفى رمضان‬-‫محمد عزت عبد السالم‬
‫معهد بحوث القطن‬
‫لرد جر‬.‫ لذدلتب هحى‬.‫ردمج ا جربمر ددى إردا إسبدت تددز ب تبح دل رترحليدوص جر ددتر‬
.‫د‬
‫تهدف‬
‫ تمر دى جفذدبت‬.‫ جرطميقدى جرحبع دى د‬.‫تزجرت جربهج ن لجتبخفجم طميقدى جسبخدتا جرب دي د‬
‫جر دز ب‬
‫ ردمج ا جربمر دى ن ر د‬.‫لركن جتبخفجم ج سبختا جرحبكمر يكون ذجب تئدف د‬.‫يم‬
.‫لأي ددت جربهجد ن ج دد‬. ‫ جددن لفيددف‬.‫حدد‬
‫ لددملر‬.‫تلبددوع دا أرد زب ر ددم مرورددى رتربددتر‬
‫جفل تص ج س لجر ى ي دي لر جتتتدا د‪ .‬ةتردى تلكدع جرل د‪ .‬جري دم‬
‫تهددف‬
‫د ف د‪ .‬جريدلتب‪ .‬لرد جر‬
‫جرفرجتددى إرددا قترس دى طميقددى جرب ددي لج سبخددتا جرحبكددمر ر ا د م ددن جرقطددن جرحيددم (‬
‫ت و ن)لتع تق ع جرهجن جربتتجى لجرج ‪ .‬جرمجرع ع جإلردت جفذد ى ‪.‬لأللدلت جرببدتئا إن بوتد‬
‫جرهجن كتست ج ‪ .‬ن جرج ‪ .‬جرمجرع ا جرحليوص ‪.‬لجت ح دن جرببدتئا ج دبز‬
‫ج رتعدتط د‪ .‬كد‪ .‬دن ج سبخددتا جرحب دي لجرحبكدمر تدوج د‪ .‬جرح بويددى ألج تجدت‬
‫دا حدى‬
‫ت د‪.‬‬
‫حدت يدفص ىددتن‬
‫جربهج ن ج د‪ .‬جر اد م يي دم دن جر ز دتب رد ن جريدلتب حدت ي دت ف جرحمردا دا ك دم ج رتعدتط‬
‫جري م مروا ر ن جريدلتب ‪.‬لأللدلت جرب بدتئا للدو‬
‫ر يبف ل ل ‪ 70‬لذلتب لو‬
‫جل جكلددم ي طددا جرحمرددا زيددت‬
‫دتئ ب ن ذجب ليدوص دتر‪ .‬رترحقترسدى‬
‫اتره رى لرترب ا جلمج جربهج ن ر ن دتئزب جرج د‪ .‬جرلتردر دم‬
‫ددا ج‬
‫بز ددتب جرورجي ددى ت ددت فو دد‪ .‬تل د ن جرحليددوص لك ددم‬
‫ج رتعددتط ر د ن جريددلتب ‪ 0‬ددا جرددمرع جن بددتر تدديي م ر د ت إ أسددى ي ددت ف دد‪ .‬زيددت ج ر د زب‬
‫جرحمرورى ا جفل تص جرقت ى‬
‫ن طميق أ‬
‫‪ .‬جرهجن لأ‬
‫‪ .‬جربعتتتب‬