physicochemical

J.Res. ANGRAU 39(1&2)37-42, 2011
COMPARISON OF DIFFERENT DIALLEL MATING DESIGNS
IN SESAME (Sesamum indicum L.)
K. PARIMALA and P. THANGAVEL
Seed Research and Technology Centre, Acharya NG Ranga Agricultural University,
Rajendranagar, Hyderabad-30.
ABSTRACT
In present study, the relative efficiency of the four methods of Griffing’s numerical approach vis-à-vis partial
diallel cross design in sesame (Sesamum indicum L.) was studied. The results indicated that the magnitude of
general combining ability variance (GCA) and specific combining ability variance (SCA) varied with the method of
analysis. The per se performance had the highest magnitude of correlation coefficients with gca effects computed
through M2 method followed by M1 method. The association between gca effects estimated through M2 v/s M4 and
M1 v/s M3 were found to be comparable. The precision of estimates of gca effects computed through partial diallel
cross analysis was affected by the sampling of the crosses. The per se performance of direct crosses had the highest
magnitude of correlation coefficients with sca effects computed through M2 method followed by M1 method. The
association between sca effects estimated through M2 v/s M4 and M2 v/s M3 methods were comparable. The rank
correlation between ranks of the sca effects of direct crosses through M1 and M3 methods differed and was not
comparable.
Key words: Sesame, combining ability, diallel cross and partial diallel cross
India is the largest producer of sesame in the
world with a production of about 6.41 lakh tonnes
from an area of 17.2 lakh hectares. However, the
productivity of sesame in India is 372 kg/ ha
compared to world average of 440 kg/ha. It indicates
that still there is a scope to enhance the production
of sesame in India by employing appropriate plant
breeding techniques. The diallel analysis is used in
crop improvement programmes to identify superior
parents for crossing and for characterizing general,
specific and reciprocal effects. In this study four
methods of Griffing’s (1956) numerical approach and
partial diallel analysis of Kempthorne and Curnow
(1961) were used for the analysis. The four methods
of diallel analysis depending on the material involved
in the study were (i) parents (n), n(n-1)/2 F 1
s and
reciprocals, (ii) parents and F 1
s only, (iii) F 1
s and
reciprocals and (iv) F 1
s only.
The different procedures when applied to same
crop variety often give a different picture of genetic
makeup. Such discrepancy can primarily be assigned
to the method of computation applied in estimating
parameters and the extent to which the assumptions
involved in each method are fulfilled. The comparative
efficiency of some of the biometrical procedures can
be of great value in assessing the true picture of the
genetic makeup of a particular crop. The accuracy
of the analysis is improved by using the appropriate
method. The present investigation was undertaken
to study the relative efficiency of the four methods
of Griffing’s numerical approach vis-à-vis partial diallel
cross design.
MATERIALS AND METHODS
The present study was based on a full diallel set
of parents viz., VNP local, VRI-1, Danbakkae,
Jinjukkae, PTDL-1 and Koteche. The 30 F 1
s (15
direct + 15 reciprocal crosses) along with six parents
were grown with a spacing of 30 x 20 cm in
randomized complete block design (RCBD), with
three replications at Experimental Farm, Department
of Agricultural Botany, Faculty of Agriculture,
Annamalai University, Annamalainagar during Rabi,
1999-2000. The recommended agronomic and
cultural practices were followed to raise healthy crop.
Observations were recorded on 15 random plants in
each genotype for days to first flower, number of
capsules / plant, 1000-seed weight (g) and seed yield
/ plant (g). Each character was subjected to
statistical analysis following Gomez and Gomez
(1983). The means of the parents, direct and
reciprocal crosses were subjected to the combining
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