Estimation of Heritable Components of Variation and Character Selection in Eggplant (Solanum melongena L.) for Mutation Breeding Programme.

Abstract

Evaluation of eggplant (Solanum melongena) genotypes, including one control check and nine mutants for ten agronomical characters to assess the magnitude of variability and to pick up the heritable component of variation present in the agronomic traits, revealed significant differences among the genotypes for all the studied characters indicating the presence of substantial genetic variability. The magnitude of phenotypic coefficient variation (PCV) was observed higher than the genotypic counterpart (GCV), indicating the greater influence of prevailing environment. High GCV and PCV have been obtained for number of fruits per plant and average fruit weight. High heritability estimates were obtained for number of fruits and leaves per plant, days to first harvest, average fruit weight; moderate for plant height, number of branches per plant, fruit length, total yield; lower in days to seed germination and internodal length. High heritability with high genetic advance over the mean (GAM) was observed for number of fruits and average fruit weight. Other characters like number of branches and fruit length exhibited moderate; while number of leaves and days to first harvest shows lowest value. Characters having high heritability with high genetic advance, therefore, indicating involvement of additive gene effect in the inheritance of these traits and thus crop improvement could brought by reliable effective simple selection. Characters showing low GAM showing absent of such type of gene action, so selection is so complicated; hence heterosis breeding should be recommended. Thus, these characters may serve as effective selection parameter in mutation breeding programme for crop improvement.

Full text

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Continental J. Biological Sciences 4 (2): 31 - 36, 2011
© Wilolud Journals, 2011 http://www.wiloludjournal.com
Printed in Nigeria


ESTIMATION OF HERITABLE COMPONENTS OF VARIATION AND CHARACTER SELECTION IN
EGGPLANT (Solanum melongena L.) FOR MUTATION BREEDING PROGRAMME

Rajib Roychowdhury1, 2 , Souri Roy1, 3 and Jagatpati Tah1
1Botany Department (UGC-CAS), The University of Burdwan, Burdwan-713104, West Bengal, India.
2Centre for Biotechnology, Visva Bharati, Santiniketan-731235, Birbhum, West Bengal, India.
3Department of Biotechnology, Vidyasagar University, Midnapore, West Bengal, India.

ABSTRACT
Evaluation of eggplant (Solanum melongena) genotypes, including one control check and nine mutants
for ten agronomical characters to assess the magnitude of variability and to pick up the heritable
component of variation present in the agronomic traits, revealed significant differences among the
genotypes for all the studied characters indicating the presence of substantial genetic variability. The
magnitude of phenotypic coefficient variation (PCV) was observed higher than the genotypic
counterpart (GCV), indicating the greater influence of prevailing environment. High GCV and PCV
have been obtained for number of fruits per plant and average fruit weight. High heritability estimates
were obtained for number of fruits and leaves per plant, days to first harvest, average fruit weight;
moderate for plant height, number of branches per plant, fruit length, total yield; lower in days to seed
germination and internodal length. High heritability with high genetic advance over the mean (GAM)
was observed for number of fruits and average fruit weight. Other characters like number of branches
and fruit length exhibited moderate; while number of leaves and days to first harvest shows lowest
value. Characters having high heritability with high genetic advance, therefore, indicating involvement
of additive gene effect in the inheritance of these traits and thus crop improvement could brought by
reliable effective simple selection. Characters showing low GAM showing absent of such type of gene
action, so selection is so complicated; hence heterosis breeding should be recommended. Thus, these
characters may serve as effective selection parameter in mutation breeding programme for crop
improvement.

KEYWORDS: Agronomical characters, character selection, eggplant, genetic advance, genetic
variability, heritability, mutation breeding, Solanum melongena.

INTRODUCTION
Eggplant (Solanum melongena L.), commonly known as brinjal or aubergine, belongs to the angiospermic
family: Solanaceae, is a popular vegetable crop grown in the tropics and subtropics (Roychowdhury and Tah,
2011a), especially consumed in Asia, Europe, Africa and America (Kalloo, 1993; Demir et al, 2010). India and
China are its primary centers of diversity (Daunay et al., 2001; Kashyap et al., 2003). S. melongena is only one
of the three cultivated species referred to as ‘eggplant’. It gained popularity in many parts of the world for its
unsurprised medicinal value and commercial importance. The other two types of eggplant are scarlet eggplant
(S. aethiopicum) and gboma eggplant (S. macrocarpon); however, S. melongena is, by far, the most important
species in terms of economic and genetic significance (Tümbilen et al, 2011) with desirable agro-economic
characteristics. The knowledge of the extent to which the desirable characters with economic values are
heritable is a prerequisite for any crop improvement programme (Roychowdhury and Tah, 2011b). Breeders
have continually retained their interest in the grouping of the germplasm and the pedigree of selected cultivars
since the information might be particularly helpful in effective breeding strategy determination (Ali et al.,
2011). For this purpose, inducible mutation is a suitable source of producing variation through mutation
breeding procedure (Domingo et al., 2007) which can produce several improved mutant varieties with high
demanding economic value (Din et al., 2004). Various traits with agro-economic value like seed weight, number
of branches, leaves, flowers, leaf area, etc. are very much complex in nature because they confirm polygenic
inheritance and greatly influenced by minute fluctuation of environmental factors. This may raise breeder’s
concern, since the genetic organization provides the base for crop enhancement of environmental adaptation,
yield and other associated attributes. The presence of adequate genetic variability between treatments of a cul-
tivar is critically important (Fasoula and Fasoula, 2002). Moreover, the genetic progress in a breeding program
is actually dependent on the variation in the present gene pool (Dreisigacker et al., 2004) associated with the
ISSN: 2141 - 4122

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Rajib Roychowdhury et al.,: Continental J. Biological Sciences 4 (2): 31 - 36, 2011


magnitude of several genetic parameters like analysis of variance of each mean value, phenotypic and genotypic
variances, phenotypic and genotypic coefficients of variation (PCV and GCV), broad sense
heritability and genetic gain. Analysis on genetic variability reveals about the presence of variation in their
genetic constitution and it is of utmost important as it provides the basis for effective selection. Wide spectrum
of genetic variability has been induced in Solanum melongena using both physical and chemical mutagens in
order to utilize it in agronomic improvement and inheritance studies (Patil, 1966; Ashri, 1970; Gowda et al.,
1996). Superior genotypes can be isolated by selection if considerable variation that exists in the population.
The extent of variability is measured by genotypic coefficient of variance (GCV) and its phenotypic counterpart
(PCV) that provides information about relative amount of variation in different characters. Variability along
with high to medium genetic advance provides enough scope for selection; however an opposite situation of this
suggests hybridization as a potential method for crop improvement (Johnson et al., 1955). In the present
investigation, an attempt has been made to assess the variability of important yield and yield contributing traits,
along with indices of variability i.e., GCV and PCV, heritability (h2) and genetic advance over mean (GA)
which would facilitate an understanding behind the expression of characters and also the role of environment to
formulate further breeding programme for character improvement through selection.

MATERIALS AND METHODS
A total of ten genotypes of eggplant or brinjal (Solanum melongena L.) including one control check and nine
mutants, after the chemical mutagenic treatment with sodium azide (SA), ethyl methane sulphonate (EMS) and
methyl methane sulphonate (MMS) as per Roychowdhury (2011) and Roychowdhury and Tah (2011c), were
grown in a randomized block design (RBD) with three replications at Crop Research Farm under the Botany
Department of The University of Burdwan, West Bengal during late winter season of 2010. Suitable plant
protection measures and normal recommended cultural practices were followed to obtain good phenotypic
expression of ten quantitative characters. In each replication, 50 plants per genotype were planted. The row to
row spacing was 75 cm and plant to plant spacing was 45 cm. The observations were recorded on 20 randomly
selected plants from each genotype for days to seed germination, plant height (cm) at maturity, number of
branches per plant, number of leaves per plant, internodal length (cm), number of fruits per plant, days to first
harvest, fruit length (cm), average fruit weight (g) and total yield (q/ha).The all data were analyzed statistically.
Mean values were subjected to analysis of variance (ANOVA) to test the significance for each character as per
methodology advocated by Panse and Sukhatme (1957, 1967). Phenotypic coefficient of variation (PCV)
and genotypic coefficient of variation (GCV) were calculated according to Burton (1952) and its classification
Sivasubrmanaian and Madhavamenon (1973). Heritability in broad sense was estimated as per Lush (1940) and
its classification as per Robinson et al. (1949). Genetic advance of the genotypes and its per cent of mean at
5% intensity of selection pressure (2.06 after Kang et al., 1983) were worked out as per Johnson et al. (1955).

RESULTS AND DISCUSSION
Analysis of variance revealed highly significant differences among genotypes for all the quantitative characters
studied (Table 1). The mean, range, phenotypic and genotypic coefficient of variation, heritability, genetic
advance and genetic advance over mean (GAM) for all the traits are presented in Table 2. In the present
investigation, the genotypes showed a wide range of variation for all the characters studied. After analysis of
variance (ANOVA) for each characters, calculated F-value ranged between 2.69 (for days to seed germination)
and 47.86 (for plant height). Medium F-value was shown by number of leaves (28.13), fruits (25.42), branches
(23.23) per plant, total yield (21.91) and average fruit weight (15.48). Low value was expressed by fruit weight
(8.99) and days to first harvest (7.08). The wide range of values provides bright scope to select superior and
suitable genotypes to be incorporated in the breeding programmes for further crop improvement.

Substantial differences within phenotypic (PCV) and genotypic (GCV) co-efficient of variation was marked for
all the studied attributes. The least difference was observed between PCV and GCV for days to seed
germination, plant height (cm) at maturity, number of branches per plant, number of leaves per plant, internodal
length, number of fruits per plant, days to first harvest, fruit length, average fruit weight and total yield. Thus,
indicating phenotypic variability to be reliable measure of genotypic variability. The PCV was higher than the
corresponding GCV for all the traits which might be due to the interaction of the genotypes with the
environment to some degree or other denoting environmental factors influencing the expression of these
characters. Close correspondence between PCV and GCV for the characters implied their relative resistance to
prevailing environmental variation. Higher values of PCV and GCV have been obtained for number of fruits per
plant and average fruit weight. High magnitude of PCV and GCV for these characters indicates the presence of
high degree of variability and better scope for improvement. Moderate levels of PCV and GCV were obtained

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for plant height, number of branches per plant, days to first harvest and total yield. However, low values have
been obtained for days to seed germination, number of leaves per plant, internodal length and fruit length, which
indicates narrow range of variation for these characters and provides very least scope for selection. This also
described that genetic factors were predominantly responsible for expression of these attributes and selection
could be made effectively on the basis of phenotypic performance. The result was in accordance with Ingale
(1993), Ingale and Patil (1997) and Rajput (1987) for number of branches/plant which exhibited moderate GCV
values and Vadivel and Babu (1988, 1993) for fruit yield which displayed high PCV and GCV estimates in
Solanum melongena.

The heritability estimates indicate the relative amount of estimates have been found to be satisfactory tools for
selection based on phenotypic performance. In the present investigation, high heritability estimates were
obtained for number of fruits and leaves per plant, days to first harvest, average fruit weight; moderate for plant
height, number of branches per plant, fruit length, total yield; lower in days to seed germination and internodal
length. The high estimates of heritability for the aforesaid characters suggested that selection based on
phenotypic performance would be more effective. However, heritability values alone may not provide clear
predictability of the breeding value. Heritability in conjugation with genetic advance over mean (GAM) is more
effective and reliable in predicting the resultant effect of selection. In the present study, high heritability along
with high GAM was observed for number of fruits per plant and average fruit weight. Other characters like
number of branches per plant and fruit length exhibited moderate; while number of leaves per plant and days to
first harvest showslow genetic advance over mean along with same category of heritability, i.e. high.

CONCLUSION
In conclusion, the present study revealed the presence of sufficient genetic variability in the available genotypes
for various characters and also having high heritability and genetic advance for certain characters. It indicated
that these characters had additive gene effect and therefore, more reliable for effective selection for bringing
about improvement in eggplant.

REFERENCES
Ali, Z., Xu, Z. L., Zhang, D. Y. He, X. L., Bahadur, S. and Yi, J. X., (2011), Molecular diversity analysis of
eggplant (Solanum melongena) genetic resources.Genetics and Molecular Research, 10(2): 1141-1155.

Ashri, A., (1970), A dominant mutation with variable penetrance and expressivity induced by diethyl sulfate in
peanuts (Arachis hypogaea L.). Mutation Research, 9: 473-480.

Burton, G. W., (1952), Quantitative inheritance in grasses. Proc. 16thInternational Grassland Congress, 1: 273-
283.

Burton, G. W. and Devane, E. M., (1953), Estimation of heritability in tall fescue (Festica arundinaceae) from
replicated clonal material. Agronomy Journal, 45: 478-481.

Daunay, M. C, Lester, R. N., Gebhardt, C. H., Hennart, J. W., Jahn, M., Frary, A. and Doganlar, S., (2001),
Genetic resources of eggplant (Solanum melongena L.) and allied species: A new challenge for molecular
geneticists and eggplant breeders. Solanaceae V. NijmegenUniversity Press, Nijmegen, Netherlands. p. 251-274.

Demir, K., Bakir, M., Sarıkamis, G. and Acunalp, S., (2010), Genetic diversity of eggplant (Solanum
melongena) germplasm from Turkey assessed by SSR and RAPD markers. Genetics and Molecular Research,
9(3): 1568-1576.

Din, R., Qasim, M. and Ahmad, K., (2004), Radio sensitivity of various wheat genotypes in M1 generation.
International Journal of Agriculture and Biology, 6: 898-900.

Domingo, C., Andres, F. and Talon, M., (2007), Rice cv. Bahia mutagenized population: a new resource for rice
breeding in the Mediterranean basin. Spanish Journal of Agricultural Research, 5: 341-347.

Dreisigacker, S., Zhang, P., Warburton, M. L. and Van Ginkel, M., (2004), SSR and pedigree analyses of
genetic diversity among CIMMYT wheat lines targeted to different mega environments. Crop Science, 44: 381-
388.

Page 4

34

Rajib Roychowdhury et al.,: Continental J. Biological Sciences 4 (2): 31 - 36, 2011


Fasoula, V. A. and Fasoula, D.A., (2002), Principles underlying genetic improvement for high and stable crop
yield potential. Field Crops Research, 75: 191-209.

Gowda, M. V. C., Nadaf, H. L. and Sheshagiri, R., (1996), The role of mutation in intra-specific differentiation
of groundnut (Arachis hypogaea L.). Euphytica, 90: 105-113.

Ingale, B. V., (1993), Diversity, heterosis and genetics of yield and quality parameters in brinjal (Solanum
melongena L.).Ph.D. Thesis. University of Agricultural Sciences, Dharwad.

Ingale, B. V. and Patil, S. J., (1997), Diallel analysis of fruit characteristics in eggplant. Punjabrao Krishi
Vidyapeeth Research Journal, 21: 30-34.

Johnson, H. W, Robinson, H. F. and Comstock, R. E., (1955), Estimation of genetic and environmental
variability in soybean. Agronomy Journal, 47: 314-318.

Kalloo, G., (1993), Eggplant (Solanum melongena L.). In: Genetic Improvement of Vegetable Crop. Kalloo, G.
and Bergh, B.O. (ed.), Pergamon Press, Oxford. p. 587-604.

Kang, M. S., Mille, J. D. and Tai, P. Y. P., (1983), Genetic and phenotypic path analysis and heritability in
sugarcane. Crop Science, 23: 643-647.

Kashyap, V., Kumar, S. V., Collonnier, C., Fusari, F., Haicour, R., Rotino, G. L., Sihachakr, D. and Rajam, M.
V., (2003), Biotechnology of eggplant. Scientia Horticulturae, 97: 1-25.

Lush, J. L., (1940), Intra sire correlation and regression of offspring on dams as a method of estimating
heritability of characters. Proceedings of American Society for Animal Production, 33: 293-301.

Tümbilen, Y., Frary, A., Mutlu, S. and Doganlar, S., (2011), Genetic diversity in Turkish eggplant (Solanum
melongena) varieties as determined by morphological and molecular analyses. International Research Journal
of Biotechnology, 2(1):16-25.

Panse, V. G., (1957), Genetics of quantitative characters in relation to Plant Breeding. Indian
Journal of Genetics & Plant Breeding, 17: 318-328.

Panse, V. G. and Sukhatme, P. V., (1967), Statistical Methods for Agricultural Workers, ICAR publication (2nd
ed.), New Delhi. p. 381.

Patil, S. H., (1966), Mutations induced in groundnut by X-rays. Indian Journal of Genetics, 26A: 334-348.

Rajput, J. C., (1987), Exploitation of F2 heterosis for yield and processing of qualities in tomato (Lycopersicon
esculentum Mill.). Ph. D. thesis. University of Agricultural Sciences, Bangalore.

Robinson, H. F., Comstock, R. E. and Harvey, P. H., (1949), Estimates of heritability and the degree of
dominance in Corn. Agronomy Journal, 41: 353-359.

Roychowdhury, R., (2011), Effect of Chemical Mutagens on Carnation (Dianthus caryophyllus L.): A Mutation
Breeding Approach. LAP Lambert Academic Publishing, Germany. p. 14.

Roychowdhury, R. and Tah, J., (2011a), Differential Response by Different Parts of Solanum melongena L. for
Heavy Metal Accumulation. Plant Sciences Feed, 1(6): 80-83.

Roychowdhury, R. and Tah, J., (2011b), Genetic variability for different quantitative traits in Dianthus
caryophyllus L. during mutation breeding. International Journal of Science & Nature, 2 (4): 778-781.

Roychowdhury, R. and Tah, J., (2011c), Mutation breeding in Dianthus caryophyllus for economic traits.
Electronic Journal Plant Breeding, 2(2): 282-286.

Page 5

35

Rajib Roychowdhury et al.,: Continental J. Biological Sciences 4 (2): 31 - 36, 2011


Sivasubrmanaian, S. and Madhavamenon, P., (1973), Genotypic and phenotypic variability in rice. Madras
Agricultural Journal, 60: 1093-1096.

Vadivel, E., Balasubramanian, S. and Babu, J. R. K., (1988), A note on nitrogen fertilization and spacing for
Brinjal. South Indian Horticulture, 36(4): 203-204.

Vadivel, E. and Babu, J. R. K., (1993), Variability and heritability in segregating population of Brinjal. Madras
Agricultural Journal, 80: 670-672.


Table 1: Analysis of variance (mean sum of squares) for different agronomic characters in eggplant (Solanum
melongena) genotypes including normal and mutant plants.

Treatments sum of
squares (TSS)
1 Days to seed germination 11.81
2 Plant height (cm) 2187.54
3 Number of branches/ plant 0.773
4 Number of leaves/ plant 51.66
5 Internodal length 2.63
6 Number of fruits/ plant 27.27
7 Days to first harvest 3.15
8 Fruit length (cm) 6.12
9 Average fruit weight (g) 0.958
10 Total Yield (q/ha) 3407.84
** Significant at 1 per cent level of probability.



Table 2: Mean, range, genotypic (GV) and phenotypic (PV) variance, genotypic (GCV) and phenotypic (PCV)
coefficient of variation, heritability in broad sense (h2
(GAM) for ten agronomic characters in brinjal (Solanum melongena L.).

Sl. No. Characters
Error mean Sum of
squares (ESS)
4.38
45.70
0.0332
1.83
0.238
1.07
0.44
0.68
0.618
155.51
Calculated
‘F’ value
2.69**
47.86**
23.23**
28.13**
11.08**
25.42**
7.088**
8.99**
15.48**
21.91**
bs), genetic advance (GA) and genetic advance over mean
Sl.
No
Characters Range
Mean
Value
± S.E.
4.31±1.7
Variance
Coefficient of
variation
GCV
0.235
h2
(%)
bs
Genetic
Advance
(GA)
0.185
GAM
(%)

4.29
GV
0.074
PV PCV
0.406 1 Days to seed
germination
Plant height
(cm)
Number of
branches/ plant
Number of
leaves/ plant
Internodal
length (cm)
Number of
fruits/ plant
Days to first
harvest
Fruit length
(cm)
Average fruit
weight (g)
Total Yield
(q/ha)
4.13-5.01 0.222 33.33
2 50.3-105.7 84.6±6.4 42.4 48.21 14.58 19.36 56.8 19.45 23.0
3 4.0-10.4 6.3±0.4 0.053 0.173 23.75 26.65 79:4 2.75 43.58
4 34.34-
85.91
2.82-4.86
60.04±0.94 33.861 37.398 0.359 0.377 90.54 10.852 18.07
5 3.83±0.31 0.144 0.402 0.367 0.613 35.82 0.28 7.31
6 3.6-22.5 11.7±0.8 2.46 3.57 41.76 43.32 92.9 9.69 82.96
7 65.1-87.1 76.2±1.9 53.87 64.53 15.19 15.72 90.6 20.80 27.26
8 12.32-27.6 19.0 ±1.04 3.972 5.562 0.561 0.638 71.41 2.932 15.43
9 30.3-124.7 75.7±5.2 51.75 62.8 36.10 37,96 90.4 54.02 71.33
10 64.0-134.3 109.4±8.0 78.4 87.48 15.04 19.56 59.1 26.18 23.82

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Rajib Roychowdhury et al.,: Continental J. Biological Sciences 4 (2): 31 - 36, 2011


Received for Publication: 22/10/2011
Accepted for Publication: 01/12/2011

Corresponding author
Rajib Roychowdhury
Centre for Biotechnology, Visva Bharati, Santiniketan-731235, Birbhum, West Bengal, India.
E-mail: rajibroychowdhurybu@gmail.com