The Journal of Research ANGRAU

Research Notes
J.Res. ANGRAU 41(1) 79-82, 2013
GENETIC DIVERGENCE IN BRINJAL (Solanum melongena L.)
BALAJI LOKESH, P.SURYANARAYANA REDDY, R.V.S.K.REDDY and N.SIVARAJ
Vegetable Research Station, A.R.I, Rajendranagar, Hyderabad-500030
Date of Receipt : 07.12.2012 Date of Acceptance : 25.01.2013
The study was conducted at Vegetable
Research Station, Agricultural Research Institute,
Rajendranagar, Hyderabad,during rabi season of
2008-09. Sixty genotypes of Brinjal collected from
various agro-climatic regions of India by N.B.P.G.R
Regional station, Hyderabad were evaluated in a
Randomized Block Design with two replications for
fourteen quantitative characters. The mean data were
analyzed following standard statistical techniques
with the objective of studying the nature and
magnitude of genetic diversity available in the
germplasm. Genetic diversity is an important factor
for any heritable improvement. Knowledge of genetic
diversity is useful for selecting desirable genotypes
from a germplasm for the successful breeding
programme. The genetic divergence between
genotypes was estimated using Mahalanobis D 2
statistic (1936).
In the present investigation, The D 2 value
was used for the final grouping of the genotypes into
eight distinct clusters as presented in Table 1. Cluster
V was the largest cluster consisting of 15 genotypes
while cluster VIII consisted of single genotype i.e,
MR/04-26. The mean inter and intra cluster D and D 2
values (Table 2) suggest that the genotypes within a
cluster are less divergent than those of different
clusters. The intra cluster and inter cluster D 2 values
ranged from 714.92 to 2452.22 and 2339.92 to
35995.80 respectively. Lowest inter cluster D 2 value
was recorded between cluster I and II (2339.92)
indicating close relationship and similarity for most
of the characters of the genotypes. Highest inter
cluster D 2 value was recorded between clusters III
and VIII (35995.80) indicating wider genetic diversity
among genotypes in these groups.
The percentage contribution of each
character towards divergence in Brinjal is presented
in Table 3.Highest contribution towards divergence
was put forth by average fruit weight (44.12%)
followed by plant spread(43.62%), average fruit length
(4.52%), number of branches per plant (2.71%),
number of flower clusters per plant (2.03%) and
average fruit diameter (1.41%) respectively. This
suggest that in order to select genotypes for
hybridization, the material should be screened for
important traits like average fruit weight, plant
spread, average fruit length, number of branches per
plant, number of flower clusters per plant and average
fruit diameter. Similar results were reported by Satesh
Kumar et al. (2007).
The mean performance of genotypes of
clusters is presented in the Table 4. In calculation of
cluster means, the superiority of a particular genotype
with respect to a given character gets diluted by other
related genotypes that are grouped in the same
cluster which are inferior or intermediary for that
character in question. Hence, apart from selecting
genotypes from the clusters which have high intercluster
distance for hybridization, it is also desirable
to have selection of parents based on extent of
genetic divergence with respect to a particular
character of interest. On the basis of the mean
performance of the characters in each cluster, the
following genotypes were identified as superior for
further genetic studies. The genotypes IC-111431 and
IC-203593 were regarded as superior for number of
flower clusters per plant. MR/04-26 was superior for
days to 50% flowering, average fruit weight, shoot
and fruit borer incidence on fruit and fruit yield per
plant.IC-111352 and IC-111428 were regarded as
superior for number of fruits per cluster.IC-13601 and
PSR-11883 were regarded as superior for number of
fruits per plant. Similar genetic divergence studies
on Brinjal in India have been carried out by many
researchers (Bansal and Mehta 2007, Sherly and
Shanthi 2007, Nandan Mehta and Mayuri Sahu 2009).
email: balajilokesh4@gmail.com
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