**Barley Genetics Newsletter 36:44-47 (2006)**

**Variability, Correlation and Regression Analysis**

**in Third Somaclonal Generation of Barley**

P. C. Kole

Dept. of Plant Breeding, G. B. Pant University of Agriculture and
Technology

Pantnagar 263 145, India

Present address: Dept. of Crop Improvement, Horticulture, and
Agricultural Botany

Institute of Agriculture, Visva-Bharati, P. O. Sriniketan 731 236

District - Birbhum, West Bengal, India

**Abstract**

Assessment of variability for qualitative and quantitative characters in
twenty five SC~3~ (somaclonal third generation) families of barley along
with their mother cultivar Dissa was made. Two male sterile plants
appearing like 'gigas' were obtained in one somaclonal family. Such
plants had empty anther sac and spikelets remained open with wide angle
for longer period. Segregation for two rowed and six rowed barley plants
occurred in four somaclonal families where mother cultivar was six
rowed. Considerable amount of variability existed among somaclonal
families for plant height, tiller number, spike area, spikelet and grain
number, 100 grain weight and grain yield per plant. Tiller number, grain
number and 100 grain weight were the major characters for variation in
grain yield in the population.

**Key words*:*** barley, SC~3~ generation, qualitative and quantitative
characters, somaclonal variation.

**Introduction**

Creation of genetic variability through tissue culture and its
exploitation have become a major thrust for crop improvement programme.
Somaclonal variation found among regenerated plants may not be stable
because of physiological disturbances and epigenetic causes. In advance
somaclonal generations, these nongenetic causes are eliminated and
whatever variation is found is due to genetic changes. Somaclonal
variation in advanced generations is sufficiently stable and can be
potentially used in crop improvement programme. Variation in
morphological characters and *Helminthosporium* resistance in SC~2~
generation and biochemical and cytological characters in SC~3~ seeds of
barley have been reported (Kole and Chawla, 1992; 1993). The present
investigation was undertaken to study variability for qualitative and
quantitative characters and to determine inter-relationships among yield
and yield contributing characters in third somaclonal (SC~3~) generation
of barley.

**Materials and Methods**

The experimental materials comprised second generation seed progenies
(SC~3~ generation) obtained from 25 initial somaclones, regenerated from
*in vitro* selected resistant calli against *Helminthosporium sativum,*
derived from immature embryo explant of cultivar Dissa. The detailed
procedures of regeneration are described earlier (Chawla and Wenzel,
1987). The 25 SC~3~ families along with parent cv. Dissa were grown at
Pant Nagar(29^o^N, 79^o^3′E, 243.83msl), Uttaranchal, India during
winter season in randomized block design with 3 replications. Each plot
consisted of 5 rows of 2m length with intra- and inter-row spacings of
7.5 and 25cm. Plants were carefully observed for changes in qualitative
characters. Data were recorded on ten randomly selected plants from each
plot in each replication for nine quantitative characters viz., plant
height, tiller number per plant, days to heading, exertion of peduncle
from flag leaf, spike area, spikelet number and grain number per spike,
100 grain weight and grain yield per plant. Estimates of phenotypic and
genotypic coefficients of variation (Burton, 1952), heritability in
broad sense and genetic advance (Johnson *et al*., 1955), correlation
coefficient (Robinson *et al*., 1951) and regression analysis (Draper
and Smith, 1981) were done following standard statistical methods.

**Results and Discussion**

Two plants in the progenies of one somaclonal family were quite distinct
from early growth phase which appeared like *gigas*. Chromosome counts
from root tip of SC~3~ seeds of this family indicated these plants to be
normal diploid. These plants were male sterile with empty anther sac and
florets remained opened for longer time with wide angle. Such male
sterility is due to segregation of nuclear recessive gene(s), induced
through the process of tissue culture.

Segregation for two rowed and six rowed barley plants occurred in the
progenies of four somaclonal families where the parent variety Dissa was
six rowed. Segregation of such somaclonal variants is due to genetic
changes, induced through the process of tissue culture.

Among the quantitative characters studied mean squares due to somaclonal
families were highly significant for all the characters studied, except
days to heading and exertion of peduncle from flag leaf, indicating
presence of somaclonal variation. Somaclonal variation for morphological
traits has been reported by Dunwell *et al*. (1986) and Sozinov *et al*.
(1988). The estimates of phenotypic coefficient of variation (PCV) and
genotypic coefficient of variation (GCV) were low for plant height and
100 grain weight; moderate for spike area and number of spikelets and
grains per spike; and high for tiller number and grain yield per plant
(Table 1). The estimates of heritability were low for plant height and
spike area; moderate for tiller number and grains per spike and grain
yield per plant; and high for spikelet number and 100 grain weight.
Genetic advances were moderate for tiller number, spikelet number and
grain yield per plant and low for rest of the characters. Moderate
genetic advance coupled with moderately high to high heritability for
spikelet number and grain yield indicates preponderance of additive gene
action for these two characters. The results of heritability and genetic
advance are in agreement Sinha and Saha (1999).

The results on genotypic and phenotypic correlations (Table 2) indicated
that grain yield per plant had positive and significant correlations
with tiller number, spikelet and grain number per spike and 100 grain
weight at both genotypic and phenotypic levels. Similar results have
been reported by Singh (1999). Among inter-character correlations,
tiller number had positive and significant correlation with spikelet
number, grain number and 100grain weight. Spikelet number also showed
positive and significant correlation with 100 grain weight, although two
rowed barley plants having less spikelet number had higher test weight.
The overall results of correlation indicated the scope of selection of
plants having higher tiller, spikelet and grain number with higher test
weight which would be high yielding.

The stepwise multiple regression analysis following step up procedure
indicated tiller number was the most important variable accounting 40.4%
variability in grain yield. The other two variables that were
sequentially included in the regression equations were grain number per
spike and 100 grain weight with the corresponding R^2^ values of 0.52
and 0.60. This indicates that tiller number, grain number and grain
weight jointly decided 60 % variation in grain yield. Therefore,
selection of plants should be based on the above three character for
improvement in grain yield.

# 

# References

Burton, G.W. 1952. Quantitative inheritance in grasses. *Proc. 6^th^
Int. Grassland Cong.* 11 : 277-283.

Chawla, H.S., Wenzel,G. 1987. *In vitro* selection of barley and wheat
for resistance against *Helminthosporium sativum*. *Theor. Appl. Genet.*
74: 841-845.

Draper, N.R. , Smith, H. 1981. The step wise regression analysis
procedure. In : *Applied Rgression Analysis (2^nd^ ed.)* pp 307-313.
John Wiley and Sons, New York.

Dunwell, J.M., Cornish,M., Powell,W., Bottino,E.M. 1986. An evaluation
of field performance of the progeny of plants regenerated from embryos
of *Hordeum vulgare* cv. Golden promise. *J. Agril. Sci.* 107: 561-564.

Johnson, H.W., Robinson, H.F., Comstock, R.E. 1955. Estimates of genetic
and environmental variability in soybean. *Agron. J.* 47: 477-483.

Kole, P.C., Chawla, H.S. 1992. Morphological and cytological variation
in second somaclonal generation of barley. *Indian J. Genet.* 52:
114-117.

Kole, P.C., Chawla, H.S. 1993. Variation in *Helminthosporium*
resistance and biochemical and cytological characteristics in somaclonal
generations of barley. *Biol. Planta,* 35: 81-86.

Robinson, H.F., Comstock, R.E., Harvey, P.H. 1951. Genotypic and
phenotypic correlations in corn and their implications in selection.
*Agron. J*. 43 : 282-287.

Singh, B.P. 1999. Correlation study in barley (*Hordeum vulgare* L.):.
*J. Appl. Biol.* 9:143-145.

Sinha,B.C., Saha, B.C. 1999. Genetic studies, heritability and genetic
advance in barley (*Hordeum vulgare* L.). *J. Appl. Biol.* 9:108-116.

Sozinov, A.A. Iskakov, A.R., Gaponenko, A.K. 1988. Somatic cell culture
-- a new source of variation for barley breeding. *Dokl. Vsesoyuz. Akad.
Sel'skokhoz. Nauk Im V.I. Lenina* 11: 3-5.

**Table 1.** **Mean, range, phenotypic and genotypic coefficients of
variation, heritability and genetic advance for seven quantitative
Characters**

+----------------+----+------+----+------+-------+-------+--------+
| Characters     | Me | R    |    | Coef |       | He    | G      |
|                | an | ange |    | fici |       | ritab | enetic |
|                |    |      |    | ents |       | ility |        |
|                |    | Min. |    | of   |       | in    | a      |
|                |    | Max. |    | v    |       | broad | dvance |
|                |    |      |    | aria |       | sense | as %   |
|                |    |      |    | tion |       | (%)   | of     |
|                |    |      |    | (%)  |       |       | mean   |
|                |    |      |    |      |       |       |        |
|                |    |      |    | Phe  |       |       |        |
|                |    |      |    | noty |       |       |        |
|                |    |      |    | picG |       |       |        |
|                |    |      |    | enot |       |       |        |
|                |    |      |    | ypic |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Plant height   | 8  | 7    | 9  | 9.27 | 5.58  | 36.3  | 6.93   |
| (cm)           | 1. | 5.03 | 8. |      |       |       |        |
|                | 57 |      | 00 |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Tiller number  | 2  | 9.33 | 3  | 2    | 21.76 | 59.1  | 34.47  |
| / plant        | 1. |      | 0. | 8.29 |       |       |        |
|                | 73 |      | 33 |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Spike area     | 2  | 2    | 3  | 1    | 12.33 | 38.75 | 15.79  |
| (cm2)          | 5. | 0.78 | 4. | 9.81 |       |       |        |
|                | 77 |      | 76 |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Spikelet No.   | 6  | 5    | 8  | 2    | 18.13 | 81.44 | 33.67  |
|                | 4. | 1.99 | 7. | 0.08 |       |       |        |
|                | 50 |      | 27 |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Grain No.      | 5  | 35.4 | 64 | 1    | 12.64 | 62.23 | 20.53  |
|                | 0. |      | .3 | 6.03 |       |       |        |
|                | 75 |      |    |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| 100 grain      | 3  | 2.79 | 4. | 9.30 | 8.23  | 78.40 | 15.14  |
| weight (g)     | .7 |      | 26 |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+
| Grain yield    | 2  | 11.5 | 34 | 2    | 22.98 | 69.00 | 39.39  |
| per plant (g)  | 4. |      | .7 | 7.61 |       |       |        |
|                | 04 |      |    |      |       |       |        |
+----------------+----+------+----+------+-------+-------+--------+

**Table 2.** **Genotypic (G) and phenotypic (P) correlation coefficients
among seven**

**quantitative characters in SC~3~ generation of barley**

+---------+---+-------+-------+---------+-------+---------+---------+
|         |   | **T   | **    | **S     | **    | **100   | **Grain |
|         |   | iller | Spike | pikelet | Grain | grain   | yield   |
|         |   | No.** | a     | No.**   | No.** | w       | per     |
|         |   |       | rea** |         |       | eight** | plant** |
+---------+---+-------+-------+---------+-------+---------+---------+
| Plant   | G | 0.52  | 0.086 | 0.      | 0.021 | 0.111   | > 0.194 |
| Height  |   | 7\*\* |       | 625\*\* |       |         |         |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P | 0.123 | 0.123 | 0.      | 0.038 | 0.028   | > 0.034 |
|         |   |       |       | 340\*\* |       |         |         |
+---------+---+-------+-------+---------+-------+---------+---------+
| Tiller  | G |       | 0.39  | 0.268\* | 0.43  | 0.247\* | > 0.    |
| No.     |   |       | 3\*\* |         | 6\*\* |         | 673\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P |       | 0.100 | 0.236\* | 0.34  | 0.214   | > 0.    |
|         |   |       |       |         | 2\*\* |         | 628\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
| Spike   | G |       |       | 0.      | 0.89  | 0.089   | > 0.    |
| area    |   |       |       | 521\*\* | 1\*\* |         | 374\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P |       |       | 0.      | 0.49  | -0.009  | > 0.179 |
|         |   |       |       | 431\*\* | 5\*\* |         |         |
+---------+---+-------+-------+---------+-------+---------+---------+
| S       | G |       |       |         | 0.52  | 0.      | > 0.    |
| pikelet |   |       |       |         | 5\*\* | 391\*\* | 365\*\* |
| No.     |   |       |       |         |       |         |         |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P |       |       |         | 0.45  | 0.      | > 0.    |
|         |   |       |       |         | 2\*\* | 295\*\* | 308\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
| Grain   | G |       |       |         |       | 0.012   | > 0.    |
| No.     |   |       |       |         |       |         | 697\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P |       |       |         |       | -0.104  | > 0.    |
|         |   |       |       |         |       |         | 532\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+
| 100     | G |       |       |         |       |         | > 0.    |
| grain   |   |       |       |         |       |         | 458\*\* |
| weight  |   |       |       |         |       |         |         |
+---------+---+-------+-------+---------+-------+---------+---------+
|         | P |       |       |         |       |         | > 0.    |
|         |   |       |       |         |       |         | 396\*\* |
+---------+---+-------+-------+---------+-------+---------+---------+

\*, \*\* : Significant at P=0.05 and 0.01, respectively.