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Estimation of heterosis and combining ability for some quantitative parameters in Gossypium hirsutum

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  • Federal Seed Certification and Registration Department

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Cotton is an important oilseed and fiber crop in Pakistan as well as in world. Improvement can be made in yield and fiber characteristics of cotton crop after understanding the various mechanisms of gene actions controlling the yield contributing traits.In the current study, four genotypes of cotton namely, NIAB-KIRN, FH-942, PB-896 and PB-76 were crossed in a random mating fashion. The parents and F1 hybrids were planted in field in three replicationsfollowing randomize complete block design. At maturity, data were collected for yield and fiber related traits. Analysis of variance of mean valuesexhibitedthe presence of significant variations. This data were analyzed for their assessment of combining ability, where it is found that the genotype NIAB-KIRN has additive gene action for number of seeds/boll, seed index and seed cotton yield per plant. Thus, nominated as a good general combiner.Whereas PB-896 × PB-76 showed good specific combining ability for seed-cotton yield/ plant and cotton-seed yield per plant, while the combination of PB-896 × FH-942 has exhibited significantly high heterosis for fiber and seedcotton yield.Based on this information the parents and combinations have potential of genetic material for yield of seed cotton as well as fiber related parameters.
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166
Chaudhary et al.
Int. J. Biosci.
2019
RESEARCH PAPER OPEN ACCESS
Estimation of heterosis and combining ability for some
quantitative parameters in
Gossypium hirsutum
Muhammad Tanees Chaudhary1, Sajid Majeed1, Amir Shakeel1 , Jia Yinhua2, Du
Xiongming2, Muhammad Tehseen Azhar1*
1Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad-38400,
Pakistan
2Institute of Cotton Research of Chinese Academy of Agricultural Sciences, State Key Laboratory of
Cotton Biology, Anyang 455000, Henan, China
Key words: Cotton; Fiber traits; Genetic effects; Hybrid vigour; SCA.
http://dx.doi.org/10.12692/ijb/15.2.166-173
Abstract
Cotton is an important oilseed andfiber crop in Pakistan as well as in world. Improvement can be madein yield
and fiber characteristics of cotton crop after understanding the various mechanisms of gene actions controlling
the yield contributingtraits.In the current study, four genotypes of cotton namely, NIAB-KIRN, FH-942, PB-896
and PB-76 were crossed in a random mating fashion. The parents and F1 hybrids were planted in field in three
replicationsfollowing randomize complete block design. At maturity, data were collected for yield and fiber
related traits. Analysis of variance of mean valuesexhibitedthe presence of significant variations. This data were
analyzed for their assessment of combining ability, where it is found that the genotype NIAB-KIRN has additive
gene action for number of seeds/boll, seed index and seed cotton yield per plant. Thus, nominated as a good
general combiner.Whereas PB-896 × PB-76 showed good specific combining ability for seed-cotton yield/ plant
and cotton-seed yield per plant, while the combination of PB-896 × FH-942 has exhibited significantly high
heterosis for fiber and seedcotton yield.Based on this information the parents and combinations have potential
of genetic material for yield of seed cotton as well as fiber related parameters.
* Corresponding Author: Tehseen Azhar tehseenazhar@gmail.com
International Journal of Biosciences | IJB |
ISSN: 2220-6655 (Print), 2222-5234 (Online)
http://www.innspub.net
Vol. 15, No. 2, p. 166-173, 2019
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Chaudhary et al.
Int. J. Biosci.
2019
Introduction
Cotton belongs to genusGossypium andfamily
Malvaceae. More than 50 speciesof genus Gossypium
are reported till now. Amongst them, 45 are diploid
and 5 are allotetraploid, whereGossypium hirsutum
and G.barbadensewhich had both A and D sub-
genomes arecultivated allotetraploid species (Chen et
al., 2007).Naturally G. hirsutum is a perennial,
woody shrub plant with indeterminate type of growth
habit (Cothren and Oosterhuis, 2010). Within
species,genetic variation is necessary to start a
breeding program for the improvement of particular
trait of interest(Azhar et al., 2009). The information
about the extent and type of genetic variation relies
on different methodologies used for its assessment
(Bajracharya et al., 2006). There are severaltypes of
breeding methods that can be utilized to achieve the
desired genetic variability in segregating populations.
These methods include selection after hybridization
and mutation (Esmail et al., 2008). The breeding
importance of different crops depends upon the
combining ability and genetic variation in relation to
traits(Ilyas et al., 2007). For the assessment of
combining abilities,diallel analysis has been used
successfully in variousfield crops like cotton(Singh et
al., 2010), wheat(Mahpara et al., 2017), rice(Shabbir
et al., 2018) and maize(Murtadha et al., 2018).
Combining ability analysis given byGriffing is
beingthought-out to be valuablefor plant
breeders(Griffing, 1956). Mating of genotypes inall
possible combinations extent the genetic variation of
filial generations and is supportive for the estimation
of both combining abilitiesi.e. general and
specific(Gilbert, 1958).Breeding tools which are
utilized for hybrid production based upon high level
of heterosis and specific combining abilities(Khan et
al., 2009). From breeding point of view, commercial
heterosis is important because it is aimed to develop
hybrids which are superior over existing cultivars in
the market.Estimation ofboth combining abilities,i.e.,
general and specific for fibre strength, fibre fineness,
ginning turn out, fiber length and fiber uniformity
ratio in previous studies suggested the idea of
selection to improve these traits(Green and Culp,
1990;Zeng and Pettigrew, 2015; Kothari et al.,
2016;Zhang et al., 2016;Zhang et al., 2017). In
another study, GCA effects werefound to be
significantforfibrestrengh, fibre length and fiber
uniformity ratio (Coyle and Smith, 1997).(Ekinci et
al., 2010)estimated the heterotic effect of yield related
parameters in G. hirsutum, and found significant and
positive effects for heterosis/hybrid vigour and
heterobeltiosis for seed-cotton yield, lint percentage
and boll weight. As both combining abilities i.e.
general and specific as well as heterosis estimates are
useful tools to determine gene action to achieve
further breeding objectives. Therefore, this research
was aimed to assess GCA, SCA and heterosis in
available cotton cultivars and advance breeding lines
for varioustraits to identify potential breeding
material.
Materialsand methods
Development of F1 hybrids and assessment in field
conditions
The presentedresearchwas conducted during the year
2016-2018 at research area of the Department of
Plant Breeding and Genetics, University of
Agriculture, Faisalabad, Pakistan. The experimental
site is situated at31.42° latitude and 73.08°longitudes.
The planting material for this study was developed by
crossing four genotypes, namely PB-76, PB-896,
NIAB-KIRN and FH-942 in a complete diallel
fashion. The parents were grown in earthen pots in
glasshouse during October 2016. The optimal growing
conditions i.e. temperature (25-35°C)and
lightintensity (25,000-30,000 lux) was maintained
for germination and growth of the plants in
glasshouse. At the time of flowering, self, direct and
reciprocals crosses were made between the genotypes.
A large number of pollinations were made in order to
produce sufficient quantity ofF0seed.Cotton seed
fromselfed and crossed bolls were picked at maturity
and kept separately in cloth bags. Later on F0seed
along with their parents was sown in field in
triplicates according to randomized complete block
design by keeping 75 ×30 cm row and plant spacing.
All the recommended agronomic practices were
adopted including thinning and proper fertigation to
have good plant population per unit area.
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2019
Data recording
At maturity, data were collected for yield and fiber
traits.The traits involved wereplant height, number of
bolls/ plant, boll weight, seed/ per boll, cotton seed
yield/ plant, seed-cotton yield/ plant,lint index, seed
index, fibre length, fibre strength, fibre fineness and
fibre uniformity ratio. When epical growth of the
main stem had ceased, the plant height startingfrom
the zero node to epical bud of five guarded plants
from each parent as well as progeny was measured by
using measuring rod.All offully opened bolls from
these plants werecounted and picked in cloth bags.
Later on, numbers of seeds per boll were counted.
Average boll weight was calculated by dividing the
total seed cotton yield per plant with the number of
pocked bolls of respective plant. The mean boll weight
of plants in each replication was calculated, likewise
cottonseed yield was also recorded for each plant for
statistical analysis.Weight of lint in a sample and
weight of seed cotton was determined to calculate
ginning turn outby using formula,
While, lint index was recorded by using the following
formula,
A high-volume instrument (modelUSTER® HVI 900
SA) available in the Department of Fiber Technology,
University of Agriculture, Faisalabad was used to
measure fiber quality parameters from clean sample
of lint obtained from bolls of selected plants. This
computerized instrument recorded fiber length (mm),
fiber strength (g/tex), fiber fineness (µg/inch) and
fiber uniformity ratio according to international
standards.
Statistical analysis
The analysis of variance was employedas proposed by
Steel et al. (1997)on recorded datato find the
genotypic variation for selected traits by using
Statistix 8.1 software(McCullagh, 2018).Once it was
known that significant variation exist in the data set,
then comining ability (Griffing, 1956) and heterosis
estimates (Falconer and Mackay, 1996) were
calculated by using Dial98 (Ukai,2006).
Results
Mean squares of various traits for genetic variability
are described in Table 1 and 2. For all the studied
traits including yield and fiber, significant variations
were found in the germplasm genotypes. These
differences indicated the suitability of genotypes for
genetic studies.
Table 1. Analysis of variance in the form of mean squares of various traits for genetic variability.
SOV
DF
PH
NB/P
BW
NS/B
CSY/P
SCY/P
SI
LI
GOT
FL
FS
FF
FUR
Replications
2
27.82
1.06
0.04
16.45
58.6
41.08
0.44
1.36
64.35
1.1
0.41
0.09
18.43
Genotypes
15
308.53**
2.48*
4.76**
57.10**
116.32**
285.80**
0.51*
1.74**
71.54*
2.72**
6.15**
0.28*
53.80**
Error
30
31.18
1.2
1.25
22.77
53.14
14.35
0.14
0.53
21.23
1.31
1.3
0.03
11.35
Where, df stands for degree of freedom; * and **, denote difference significant at 5% and 1% probability levels,
respectively.
It wasfound that NIAB-KIRNexhibited highest
positive GCA effect for cottonseed yield (Table
3).Furthermore, PB-76 and FH-942 had maximum
positive and significant GCA for number of seeds/boll
and yield of cotton-seed respectively.PB-896 showed
significant and maximum GCA for uniformity ratio of
fibre.The cross among NIAB-KIRN × FH-942
exhibited positive SCA for plant height while its
parental genotypes exhibited negative GCA for this
trait.The hybridof PB-76×PB-896 revealed
maximumeffects ofSCA for number of bollsper
plant,fiber fineness and seed index. While hybrids
namely, FH-942 × PB-76 and PB-896 × PB-76
showed negative SCA fornumber of boll per plant
WhileFH-942×PB-76 revealed as good specific
combiner for seed index and boll weight. PB-896 ×
FH-942 was proved to be best combination for
uniformity ratio of fiber and seed/boll. For yield of
seed cotton and GOT%, hybrid PB-896 × NIAB
KIRNexhibited highest value for SCA.
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Int. J. Biosci.
2019
Table 2. Analysis of variance in the form of mean squares of various traits for combining ability analysis.
SOV
DF
PH
NB/P
BW
NS/B
CSY/P
SCY/P
SI
LI
GOT
FL
FS
FF
FUR
GCA
3
8.66**
1.42*
0.20*
0.45*
63.67**
111.06**
0.02**
0.22ns
11.02**
0.69*
0.80*
0.06*
12.45**
SCA
3
216.51**
0.97*
2.72**
3.65**
33.85**
83.01**
0.13*
1.05*
25.28**
1.69*
4.00**
0.14*
14.87*
Reciprocals
6
15.73*
0.77*
0.84*
0.96*
13.44*
55.87*
1.45*
0.56*
6.78*
2.77**
3.66*
0.58**
6.76*
Error
30
2.09
0.19
0.45
1.53
2.84
23.66
2.04
1.38
7.34
2.65
1.73
0.45
3.87
Note: List of abbreviations has been provided.
The cross of FH-942 × NIAB KIRN displayed positive
significant SCA for fiber length. The cross among
NIAB KIRN × PB-76 showed positive SCA for fiber
strength.These findingsindicated the existence of
non-additive gene behavior ingoverning
theseparameters.
In addition to combining ability, the heterotis
percentages for all of traits are briefed out in Table
4.The hybrid of NIAB-KIRN × FH-942 exhibited
maximum heterosis for plant height while indirect
cross of these accessions exhibited highly significant
heterosis for number of bolls per plant. For number of
seeds per boll and boll weight, PB-896 × FH-942
showed highest heterosis estimates.Heterosis %age
was ranged from 2.01% to 26.23% for plant
height.Nine out of twelve hybrids displayed
maximum positive and significant heterosis. PB-76 ×
FH-942 showed highest hybrid vigor for boll
weightwhile the hybrid PB-896 × PB-76 exhibited
highest heterosis estimate for seed present per boll
and yield of seed-cotton.
The heterosis was ranged from 2.43 to 56.74% for
seed-cotton yield per plant.Maximum heterosis %age
for fibre length (11.89%) and fibre strength (8.4%)
were exhibited by hybrids PB-896 × PB-76 and PB-76
× FH-942, respectively.
Table 3. General and specific combining ability effects data for all traits.
Crosses
PH
NB/P
BW
NS/B
CSY/P
SCY/P
SI
LI
GOT
FL
FS
FF
FUR
P1
0.80*
0.69 **
0.08
0.92
-0.44
-0.26
-0.03
0.20
-1.58
-0.04
0.40
0.11 *
1.42
P2
1.20*
-0.44
-0.07
1.72*
-0.61
1.47
-0.06
-0.27
1.72
-0.46
-0.49
-0.14 **
-0.62
P3
-0.65*
-0.07
-0.22
1.42
4.45 **
5.95 *
0.07
0.03
0.06
0.27
0.06
0.03
0.92
P4
-1.35*
0.18
0.21
0.62
3.39 *
4.23*
0.03
0.04
-0.20
0.23
0.03
-0.01
-1.72 *
P1 × P2
-14.55**
-1.68 **
-1.72 **
-0.40
10.61**
15.78 **
0.49 **
-1.19 **
2.75*
-2.32**
-3.82 **
-0.74 **
-0.40
P1 × P3
6.65
-0.24*
0.94 **
-3.09 **
-2.37
-2.58
0.35**
0.51 **
5.05**
0.24
0.12
-0.13 *
-3.09 **
P1 × P4
-12.33 *
-0.73 *
-1.36 **
6.43 **
2.59
4.0
0.34**
-0.12
-4.37**
0.48
-0.28
-0.03
6.43 **
P2 × P1
0.34
2.21*
2.75*
4.55**
2.34*
0.65
3.28*
3.11**
0.65
1.98*
0.045
3.43**
4.55**
P2 × P3
-10.21
0.29 *
-1.45 **
3.36 **
-4.22 *
-7.36 *
-0.07
1.17 **
2.8*
0.23 ns
1.68 **
0.25 **
3.36 **
P2 × P4
9.09
0.77*
0.82 *
-1.03
-3.85 *
-2.58
0.19*
-1.20 **
-3.87**
-0.79 *
1.08 **
0.05
-1.03
P3 × P1
2.45*
-0.43 *
-0.39
-3.45**
0.46
0.76*
-2.11*
-1.83
2.87**
-0.34
0.34
-2.43*
-3.45**
P3 × P2
-0.24
0.32 *
-2.67*
2.65*
-3.45*
-1.89
0.30
0.44
-3.67**
2.76*
3.45**
1.63
2.65*
P3 × P4
20.64 **
0.37 *
-1.70 **
2.39 *
3.31
7.79 *
-0.02
0.21
-5.14**
-0.86 *
0.16
-0.08
2.39 *
P4 × P1
-1.54*
0.42 *
0.03
-1.33
-2.31
6.87*
-3.21*
-2.56*
0.38
-3.38**
-2.98**
0.03
-1.33
P4 × P2
0.34
-2.64*
3.45*
0.27
5.34*
-5.34
3.45*
-0.55
-0.45
-1.75
-0.34
0.31
0.27
P4 × P3
-0.45
3.45**
0.29
2.12*
0.045
2.45
0.54
1.56
0.29
4.28**
-0.31
0.45
2.12*
Where, P1= PB-896, P2= PB-76, P3-=NIAB-KIRN, P4= FH-942.
Discussion
Genetic improvement in vegetative and reproductive
traits of cotton relies on the magnitude of genetic
variation that exists in germplasm. Therefore, plant
breeders are keen to know about the genetic
component of variation for the concerned trait.
Biometrical data showed significant variation for all
parameters observed in this research. The genetic
component of variation is thanadditionally divides
into two elementsi.e. GCA and SCA.These
components provide appropriate understanding
about genetic control of plant traits. LowerGCA to
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Chaudhary et al.
Int. J. Biosci.
2019
SCA ratios revealed theprevalence of non-additive
gene action for studied traits. These findings were in
conformitywith (Aslam et al., 2015;Maqboool et al.,
2017;Khokhar et al., 2018).However, Raufet al.
(2005) reported that the involvement of both additive
and non-additive genetic effects for fiber traits.
Parental lines with maximumSCA estimates are
expected to produce productive hybrids by crossing
with suitable testers.Significant GCA effects for
parents indicated the possibilities of transferring
these traits to progenies(Samreen et al., 2008). The
use parents either with positive or negative GCA
depends upon the nature of traits and target of
breeding programs. For example, parents showing
positive GCA for yield of seedcotton can be used to
enhance yield through breeding while for plant height
and fiber fineness, parents with negative GCA are
suitable as lower or medium values for these traits are
desirable(Ashokkumar et al., 2010).
Table 4. Heterosis percentages data for all studied traits.
Crosses
PH
NB/P
BW
NS/B
CSY/P
SCY/P
SI
LI
GOT
FL
FS
FF
FUR
P1 × P2
-21.50
-7.93
-64.20 **
64.39 *
58.98*
56.74 *
14.56**
-36.40 **
10.56 ns
11.89**
-20.98 **
-19.83 **
2.09 ns
P1 × P3
2.52
3.96
-3.47 ns
2.75 ns
20.22 ns
25.56 ns
-6.09
18.74*
18.16 *
-0.88 ns
-1.58 ns
6.36 *
-4.12 ns
P1 × P4
-21.11
0.03
52.59**
53.45**
6.17 ns
15.33
18.77**
-12.20 ns
-17.14*
-0.71 ns
-4.26ns
-4.85 ns
24.72 **
P2 × P1
7.23
0.23
25.34ns
-14.47 ns
21.67 ns
23.21 ns
2.33 ns
12.39*
17.24*
1.02 ns
2.01 ns
2.02 ns
22.56**
P2 × P3
2.56
0.28
32.73 ns
4.28 ns
12.34*
16.52
3.70*
10.34 ns
17.22 ns
3.11*
4.21ns
11.02 *
12.89 *
P2 × P4
-17.39
0.01
-62.66 **
21.32 ns
-10.34 ns
8.49
-0.57 ns
35.02 *
9.83 ns
-2.01 ns
8.49 *
-2.95 ns
11.55 ns
P3 × P1
5.67
2.07
-7.18 ns
35.56**
3.22 ns
2.43 ns
8.77 *
38.80 **
-15.51 *
-6.19 ns
4.65 ns
-1.32 ns
3.99 ns
P3 × P2
26.23*
15.23
2.03 ns
-12.34 ns
-26.20 ns
-14.23*
1.88 ns
10.21 ns
13.22*
0.23 ns
3.12 ns
23.88**
-3.55 ns
P3 × P4
2.01
1.02
14.23 ns
23.37 ns
2.76 ns
-6.90
7.54*
34.32*
12.32*
3.22 ns
2.21 ns
2.93 ns
0.45 ns
P4 × P1
14.21
-2.20 ns
23.43*
14.21**
34.12 ns
2.54
2.76ns
2.87 ns
10.23 ns
4.22 ns
2.01 ns
3.23 ns
4.23 ns
P4 × P2
13.44
21.43*
12.11 ns
4.75 ns
33.59 ns
-11.54
0.03 ns
12.23*
13.22 *
3.02 ns
3.12 ns
2.04 ns
2.01 ns
P4 × P3
21.13*
2.20 ns
-64.27 **
3.75 ns
19.32*
43.83 ns
-0.20 ns
9.81 ns
-18.66 *
-4.28 ns
3.95 ns
-1.63 ns
13.74*
Where, P1 = PB-896, P2= PB-76, P3= NIAB-KIRN, P4= FH-942.
Present study displayed significant heterosis for fiber
and yield parameters. Results regarding heterotic
effects for seed cotton yield/plant suggested that five
F1 hybrids displayed positive and significant
heterosis.Comparison between the observed heterosis
of hybrids and the GCA effects of their parents
revealed the range of heterosis. Most of the
productive hybridsi.e. (NIAB-KIRN×PB-896)
and(PB-76 × PB-896)were the results of crosses
between parents exhibiting high and low GCA
estimates(Arain et al., 2015). Generally, high
heterosis(Bilwal et al., 2018)was observed in those
crosses where one of the two parents had quite lower
GCA estimate as compare to others. Some of hybrids
were observed with high heterosis values from the
crosses between two parents having high GCA
estimates(Patil, 2018). In many cases, the crosses
between parents possessing high GCAs for a given
traits results into inferior hybrids(Jatoi and Memon,
2016). Thus, based upon the results, the hybrid PB-
896 × PB-76 exhibited superior SCA for yield of
seedcotton and cottonseed yield per plant while the
hybrid PB-896 × FH-942 exhibited highly significant
heterosis for yield of seed cotton and fibre related
parameter. The mentioned results are in accordance
with (Kannan and Saravanan, 2016;Tigga et al.,
2017;Balakrishna et al., 2017).The genetic
components are highly influenced by environmental
conditions, so potential of these hybridscould be
assesses after cultivation in multi-location trials in the
cotton belt of Pakistan.
Conclusion
The investigations found in this study opened the
avenues for exploitation of parents and their hybrids
for heterosis breeding for various traits. The higher
values of GCA, SCA and heterosis indicate that there
is great chance to select the potential genotype for
certain traits which can be exploited in future for
advancement of yield and fiber related parameters.
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2019
List of abbreviations
GCA, general combining ability, SCA, specific
combining ability, PH, plant height; NB/P, number of
bolls/plant; BW, boll weight; NS/B, number of seed/
boll; CSY/P, cotton seed yield/ plant; SCY/P, seed
cotton yield/plant; SI, seed index; LI, lint index; GOT,
ginning out turn; FL, fiber length; FS, fiber strength;
FF, fiber fineness; FUR, fiber uniformity ratio.
Declaration of interest
Not applicable.
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... Combining ability (GCA & SCA) estimates were utilized to find out the potential of parents and their combinations for improving the desired traits (Memon et al. 2014;Chaudhary et al. 2019). The good general combiner parents may not always produce good specific combinations for all traits. ...
... It was earlier suggested by Ali et al. (2016) and Kaleem et al. (2016) that based on higher SCA effects along with non-additive gene action, such traits may be improved through developing different hybrid combinations. Whereas higher GCA variance indicated additive gene action, which described that improvement may be possible through simple selection process (Memon et al. 2014;Chaudhary et al. 2019). ...
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Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential. This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids. Fifty cotton genotypes and 40 F 1 (hybrids) were tested under field conditions following the treatments, viz., high temperature stress and control at peak flowering stage in August and October under April and June sowing, respectively. Results The mean squares revealed significant differences among genotypes, treatments, genotype × treatment for relative cell injury, chlorophyll contents, canopy temperature, boll retention and seed cotton yield per plant. The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index (HSI). The heat tolerant genotypes including FH-Noor, NIAB-545, FH-466, FH-Lalazar, FH-458, NIAB-878, IR-NIBGE-8, Weal-AG-Shahkar, and heat sensitive, i.e., CIM-602, Silky-3, FH-326, SLH-12 and FH-442 were hybridized in line × tester fashion to produce F 1 populations. The breeding materials’ populations (40 F 1 ) revealed higher specific combining ability variances along with dominance variances, decided the non-additive type gene action for all the traits. The best general combining ability effects for most of the traits were displayed by the lines, i.e., FH-Lalazar, NIAB-878 along with testers FH-326 and Silky-3. Specific combining ability effects and better-parent heterosis were showed by the crosses, viz., FH-Lalazar × Silky-3, FH-Lalazar × FH-326, NIAB-878 × Silky-3, and NIAB-878 × FH-326 for seed cotton yield and yield contributing traits under high temperature stress. Conclusion Heterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits. The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars, and hybrids for high temperature stress tolerance.
... By accumulating all of the above traits in descending order, the earliness index accounts for significant heterotic potential, which is vital for the crop's early development (Rani et al., 2020). To analyze heterosis performance for the development of early maturing cotton hybrids, plant breeders must understand several earliness characteristics, including days to flowering, days to first flower bud opening, days to bolls maturity period, number of nodes on the first fruiting branch, and earliness index (Chaudhary et al., 2019). Due to the cotton crop's limited genetic diversity, it is essential to develop novel hybrids with superior heterosis performance. ...
... Utilizing hybrid vigor in industrial cotton production is a popular subject. Pakistan can reap the benefits of cotton heterosis by developing early maturing cultivars and increasing production per acre (Ali et al., 2019;Chaudhary et al., 2019;Khalid and Amjad, 2018;Khalid and Amjad 2019;Malik and Rasheed 2022;Rana et al., 2021). Keeping heterosis in mind, the purpose of the present study is to evaluate the heterosis performance of various yield and earliness-related traits. ...
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Cotton is a long duration crop which effects the timely sowing of wheat in Pakistan. Information of various earliness and yield related traits are pre-requisite to develop early maturing and high yielding cotton cultivars. Therefore, the present research was conducted to determine the heterotic potential for six earliness and six yield related. For this purpose, 10 F1 hybrids were developed through crossing between nine upland cotton cultivars. These hybrids along with their parental lines were sown in the field conditions of Faisalabad, Pakistan. All the hybrids showed significant differences for observed traits. The maximum recorded values of heterosis for earliness index and seed cotton yield were 66.05% and 70.39%, respectively. Hybrid VH-289 × AGC-501 showed maximum significant heterosis (66.05%), heterobeltiosis (50.43%) and standard heterosis (32.52%) for earliness index was due to the negative heterosis in days to flowering, days to first boll opening, node number for first fruiting branch and height of first fruiting branch. Hybrid ARK-3 × AGC-501 showed maximum significant heterosis (70.39%), heterobeltiosis (28.52%) and standard heterosis (72.01%) for seed cotton yield was due to the positive heterosis showed by its yield contributing traits. This study can be used for breeding program to develop early maturing and high yielding varieties.
... These findings are reasonable and might be due to inbreeding depression existing the F 2 which would reduce the heterosis effects. Significant differences among genotypes for grain yield and related traits in different sets of material of cotton were reported by Taha et al. (2018); Chaudhary et al. (2019) and El-Aref et al. (2019). ...
... Meanwhile, the non-additive play the important role in inheritance the other cases. The significance of additive and non-additive gene action with more pronounced non-additive effect in heredity of cotton characters was disclosed previously by numerous authors as Ekinci and Basbag (2018); Taha et al. (2018) and Chaudhary et al. (2019). The correlation between parental mean performance and i ĝ effects were significantly positive for most studied traits in F 1 and F 2 .This indicates highly valuable agreement between the parental performance and its i ĝ effects. ...
... Additionally, diallel analysis enables breeders to detect the most efficient selection method through estimating the genetic nature of evaluated qualitative and quantitative characters (Başal and Turgut, 2003;Salgotra et al., 2009). Chaudhary et al., (2019) found that the genotype NIAB-KIRN had additive gene action for seed index and seed cotton yield and proved to be a good combiner. While the cross PB-896 × PB-76 showed good SCA for seed cotton yield and cotton seed yield, revealing the importance of non-additive gene effects for such traits. ...
... barbadense L.) as reported by Yehia & El-Hashash (2019), EL-Mansy et al. (2020), Mokadem et al. (2020), Amer et al. (2021), Hamed & Said (2021) and Max et al. (2021) as well as in upland cotton (G. hirsutum L.) as reported by Chaudhary et al. (2019), Patel et al. (2019), Manonmani et al. (2020) and Chakholoma et al. (2022). ...
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Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop productivity. This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids. The fifty cotton genotypes and 40F1 were tested under field conditions following the treatments viz., high temperature stress and control at peak flowering stage during August and October under April and June sowing, respectively. Results The means squares revealed significant differences among genotypes, treatments, genotype×treatment for relative cell injury, chlorophyll contents, canopy temperature, boll retention and seed cotton yield. The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index (HSI). Based on HSI and cluster analysis eight tolerant genotypes (FH-Noor, NIAB-545, FH-466, FH-Lalazar, FH-458, NIAB-878, IR-NIBGE-8 and Weal-AG-Shahkar) and five sensitive (CIM-602, Silky-3, FH-326, SLH-12 and FH-442) were selected for hybridization. The breeding material, 40F1 and 13 parents evaluated following line×tester design. Higher specific combining ability variances with dominance variances determined the non-additive gene action for all the traits. The best general combining ability effects for most of the traits were displayed by lines FH-Lalazar, NIAB-878 along with testers FH-326 and SILKY-3. Specific combining ability effects and better-parent heterosis were showed by crosses FH-Lalazar×SILKY-3, FH-Lalazar×FH-326, NIAB-878×SILKY-3 and NIAB-878×FH-326 for seed cotton yield and yield contributing traits under high temperature stress. Conclusion Consequently, heterosis breeding for non-additive type of gene action, may utilize the potential parents in different cross combinations to develop high temperature tolerance in local cotton cultivars and hybrids for improving seed cotton yield .
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Provitamin A bioforitification of maize endosperm was found to be most convenient solution to the resolve its deficiency in the masses. Continuous efforts for persistent evaluation of diverse genetic material are prerequisite for genetic improvement of maize endosperm for provitamin A. Distinctively selected inbred lines and testers were evaluated for their yield and provitamin A related performance in single cross F1 hybrid combinations. Total 50 single cross hybrids were evaluated for different agronomic and carotenoid related traits. Significant differences were observed among genotypes, lines, testers and line × tester interaction for studied traits. L5, L6 and T1 had high GCA effects for YPH, RPC and FW whereas, L1, L5 and T4 had high GCA effects for TCC, PVAC and NPVAC. Among studied crosses, L7×T3, L8×T4 and L5×T2 had high SCA effects for PVAC whereas, L2×T5, L3×T3 and L4×T2 had high SCA effects for YPH. L3×T3 had high SCA effects for YPH, TCC, PVAC and NPVAC. L8×T4 had high SCA effects for PVAC, RPC and FW. L2×T5 had high SCA effects for PVAC, YPH, NPVAC and TCC. Most of variability was contributed by L×T interaction which showed that performance of the parents could only be evaluated in specific cross combinations. Phenotypic variances and phenotypic coefficient of variations were higher which showed that performance of the crosses was also dependent on the environmental factors. Gene action showed that all of the traits were under the control of non-additive gene action which strongly directs the manipulation of heterosis breeding for genetic improvement of studied traits. L3×T3, L5×T4, L3×T1, L4×T3, L2×T1, L8×T3 and L5×T2 for RPC and TCC whereas, L1×T1, L3×T5, L7×T1, L10×T5, L7×T2 and L9×T1 for FW, YPH and PVAC had highest better parent heterosis. Results of Kempthorne's analysis and GGE biplot analysis were comparable for estimation of GCA, SCA effects and identification of desired crosses. Therefore, GGE biplot could be preferred for providing visual explanation of the effects and additionally provides information about heterotic grouping of testers, SCA effects of parents, best parent and best crosses. Combining ability, gene action and heterosis studies based on Kempthorne's analysis and GGE biplot analysis revealed that genetic improvement can be made for studied agronomic and carotenoid related traits. Improvement of yield and provitamin A carotenoids may help the peoples of Pakistan to suffice the food security issue and to alleviate the sub-clinical symptoms of vitamin A deficiency.
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The experimental research was conducted so as to determine the general combining ability (GCA) and specific combining ability (SCA) estimates and heterotic effects for seed cotton yield and fibre traits in 5 × 5 half diallel crosses of upland cotton {Gossypium hirsutum L.). The parental genotypes studied were; CRIS-134, IR-3701, IR-1524, FH-113 and MG-6. The characters such as bolls/plant, sympodial branches/plant, boll weight (g), plant height (cm), fibre length (mm), seed cotton yield/plant (g), seed index (g) and ginning outturn percentage were studied. The experiment was laid-out in a randomized complete block design with four replications at experimental field of the Department of Plant Breeding & Genetics, Sindh Agriculture University Tandojam, Pakistan during 2013. The results revealed that, parents and hybrids differed significantly for their mean performance regarding all the traits studied. The importance of heterotic effects was evident from the significance of parents vs. hybrids performance. The variances due to GCA and SCA were significant for all the traits except that GCA was non-significant for boll weight only whereas, SCA was non-significant for boll weight, seed index and ginning outturn %. The significance of GCA indicated the importance of additive genes advocating the traits while, the involvement of nonadditive genes was evident from the significance of SCA variances. The GCA variances were greater than SCA for bolls per plant, plant height, seed cotton yield and lint % while, SCA variances were higher than GCA for sympodial branches/plant and fibre length. Parents IR-3701, FH-113 and MG-6 displayed higher positive GCA effects for bolls/plant, sympodial branches/plant, fibre length, seed cotton yield, seed index and ginning outturn%. The per se performance of these three parents was exactly reflected in their GCA effects and such happenings are exceptional. Such results suggested that, all three parents were good general combiners covering most of the traits studied and may be preferred for hybridization and selection programmes. The crosses like CRIS-134 × MG-6, IR-3701 × FH-113 and IR-3701 × MG-6 with higher estimates of SCA for almost all the traits also expressed higher heterotic effects, thus these hybrids with dominant and over dominant genes could be potential hybrids for the exploitation of heterosis in cotton.
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Utilization of stress tolerant maize is the key to sustainable production and food security, and hence studies were conducted at Dirab Research Station, Riyadh, Saudi Arabia, from 2009 to 2010 to estimate General Combining Ability (GCA), Specific Combining Ability (SCA) and their interactions with environment. Non-reciprocal diallel crossing was performed among six inbreds. The inbreds, 15 F1 hybrids and two checks were evaluated in split plot design. Regulated irrigation commenced before tasselling and stopped before grain filling stage, using Food and Agriculture Organization (FAO) evaporation pan as guide. Water was applied when pan reading was at 50, 70 and 90in. to create E1, E2 and E3 environments respectively. Data were analyzed using method 3 of Gardner and Eberhart. Analysis of variance showed highly significant variance (P⩽0.01) among almost all sources of variation. High significance GCA and SCA observed revealed the importance of both additive and non-additive genetic actions, while low GCA/SCA implied importance of dominant effects of gene. Anthesis-silking interval (ASI) was the most affected trait by water deficit indicating that selection for tolerance could be based on short ASI. Performance per se of the genotypes reveals the importance of hybrids with P1 and P6 but failed to indicate their suitability as combiners. The KSU 6–47 had highest significant GCA for grain yield under E1 and E2. KSU 3–69 had the lowest significant negative GCA for days to tasselling, while cross KSU 6–47×KSU 3–69 with high SCA for grain yield and 1000-kernel weight under all environments suggested their usefulness for improvement.
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Combining ability was studied for identification of potential cultivars and hybrids, and the nature of gene action involved for inheritance of cottonseed traits and oil content % in a 6x6 diallel cross in upland cotton (Gossypium hirsutum L.) during 2003-2005. Analysis of variance revealed highly significant (p≤0.01) differences among the genotypes for all the traits. Combining ability studies showed that the mean squares due to general combining ability (GCA) and specific combining ability (SCA) were mostly significant in F1 and F2 generations. Genetic components of variances due to GCA and SCA revealed that most of the traits were controlled by additive type of gene action in both generations because of greater GCA variances. However, seeds per boll and cottonseed oil % in F1 generation gained preponderance of SCA variances having non-additive type of gene action. Cultivar CIM-1100 was found as leading general combiner in combination with other cultivars BH-36 and CIM-240, FH-682 and CRIS-9, and their hybrids (CIM-1100 x BH-36, CIM-240 x CIM-1100, FH-682 x BH-36, CIM-1100 x FH-682 & CIM-1100 x CRIS-9) showed prominent SCA and renowned mean performance for seeds per boll, seed index and cottonseed oil content %. Therefore, involvement of CIM-1100 in most of the hybrids resulted in the synthesis of superior genotypes for all the traits.
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Saline soils are the source of severe abiotic stress, which hinders crop productivity. To compete the challenges of food security for rapidly growing population of the world, it is necessary to utilize marginal lands for cultivation by developing saline adapted varieties. Total six elite maize lines were used as parents following diallel mating design. Resultantly 30 F1s were generated. Data were recorded for different adaptability indicators under saline environments in maize. Differences among mean squares for general combining ability (GCA), specific combining ability (SCA) and reciprocal effects for all the indicators were highly significant. Root length, shoot length, Na+ and K+ ion contents were governed by non-additive type of gene action whereas; leaf area was controlled by additive gene action. Under different saline environments, better adaptability level regarding GCA, SCA and their reciprocal effects were indicated in maize genotypes L7-2, OH-41 and WFTMS. The cross Q67 × L7-2 exhibited comparatively highest level of adaptability regarding SCA effects under saline environments. For reciprocal effects maize genotypes L7-2, Q67, OH-41 and WFTMS could be used in different crossing combinations for the development of maize hybrids adapted to different saline environments.
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The present study is aimed to estimate general combining ability of the parents and specific combining ability and heterosis of hybrids for seed cotton yield and fibre quality traits. Three female lines crossed with six testers in line x tester fashion. Analysis of variance for combining ability indicated the predominance of non-additive gene action for all the characters under study except plant height, 2.5% span length and oil content. The parents AK032 and AK053 among the lines and DR-7R among the testers were found to possess significant GCA effects for most of the yield contributing characters. Maximum heterosis for seed cotton yield per plant was recorded by AK023 x DR-7R over the standard check. The highest significant heterosis in desirable direction for fibre strength was recorded by AK023 x DR-7R followed by AK023 x AKH-976 over the check.
Article
A five‐parent half diallel mating design was utilized to determine the potential for the simultaneous improvement in yield, fiber quality, and yarn strength in upland cotton ( Gossypium hirsutum L.). In addition, fiber traits were measured by standard laboratory instrumentation (SLI) and high volume instrumentation (HVI) to compare their usefulness to breeders in population improvement. The 10 F I populations plus the parental lines were grown in a randomized complete‐block design in 1983 at two locations each with a different soil type at the Pee Dee Research and Education Center, Florence, SC. Significant general combining ability (GCA), which may approximate additive genetic effects, was detected for 2.5 and 50% fiber span length (SLI measurement), uniformity (SLI measurement), yarn strength, yield, and lint percentage. Therefore, progress from early generation selection could be expected in these populations. There were no significant GCA effects for any of the HVI fiber measurements, and it was concluded that HVI is not as useful to breeders in detecting small genetic differences as HVI is to the textile industry for which it was developed. There was some evidence of nonadditive genetic effects for some of the fiber traits by a general test of heterosis, although it was not detected by the test for specific combining ability. No single parent exhibited high GCA effects for yield and all fiber traits, thus simultaneous improvement in multiple fiber traits and yield probably will require intermating of several parental lines. However, simultaneous improvements in yield and yarn strength could be expected from crosses with PD 3249 and SC‐1, thus providing further evidence of the breakup of unfavorable linkages.