Sarkar et.al.
and seven monoecious viz. PRG 117, PRG 142, PRG
harvesting five parents showed highly significant
131, PRG 137, PRG 132, PRG 120 and PRG 7 (Pant
gca effect which is ranged from -1.41 (PRG 117) to
Torai 1) ridge gourd. Row to row distance 3.5 m
2.09 (PCPGR 7256). Three parents showed the effect
and plant to plant spacing taken 0.6 m and each
in desirable negative direction i.e. PRG 117 (-1.41),
genotype consist eight plants. Observations were
PRG 137 (-0.71) and PRG 120 (-0.51). Regarding vine
recorded from five randomly selected plants on days
length the extent of gca effect ranged from -0.44
to first female flower, node number to first female
(PRG 142) to 0.83 (PRG 131) where only two parents
flower, vine length (m), number of primary branches
showed the effect in positive direction i.e. PRG 131
and days taken to Ist fruit harvesting. Combining
(0.83) and PRG 132 (0.38). Only two parents showed
ability analysis was carried out according to Griffing
significant gca effects in aspect of number of primary
(1956b) method II model I. In this approach, using
branches i.e. PRG 131 (0.26) and PRG 117 (0.22).
a suitable statistical model the component variances
due to general and specific combining ability was
Table 2: Estimates of general combining ability effects of
estimated. Heterosis was calculated on over better
parents for different traits in ridge gourd
parent (BP) and check parent (CP) for each character.
Parent PRG 7 (Pant Torai 1) was taken as check for
Node
Days
Days
Number
standard heterosis.
number
Vine
taken to
to first
of
Parents
to first length
Ist fruit
female
primary
female
(m)
harves-
Results and Discussion
flower
branches
flower
ting
Thereweresignificantdifferencesamongtheparental
PCPGR
2.73**
-0.26
-0.10**
-0.18
2.09**
lines with respect to different characters studied. The
7256
mean performance of eight parental lines along with
PRG 117
-1.70**
0.54**
-0.12**
0.22*
-1.41**
28 F1 hybrids is given in Table 1.
PRG 142
-0.57** -1.13**
-0.44**
-0.04
-0.24
PRG 131
0.30
0.77**
0.83**
0.26**
0.02
The estimates of general combining ability (gca)
PRG 137
-0.70** -0.49**
-0.09**
-0.14
-0.71**
effects of eight parental lines for all the five
quantitative characters are presented in Table 2. It
PRG 132
0.53**
0.41**
0.38**
0.09
0.66**
would be imperative to mention here that for the
PRG 120
-0.47*
-0.16
-0.28**
-0.14
-0.51**
characters days to first female flower, node number
PRG 7
-0.13
0.31*
-0.17**
-0.08
0.09
to first female flower and days taken to Ist fruit
SE (gi)
0.69
0.47
0.10
0.33
0.63
harvesting, the negative gca and sca effects were
* significant at 0.05 levels of probability
considered to be desirable, as it indicates earliness.
** significant at 0.01 levels of probability
In the present study good general combiner for
The general combining ability is primarily the
different traits have been identified on the basis
function of additive and additive × additive gene
of estimates of gca. For the character days to first
action. According to Gilbert (1967), the additive
female flower six parents exhibited significant gca
parental effects are of more practical use to the
effects ranging from -1.70 (PRG 117) to 2.73 (PCPGR
breeders than non-allelic interaction, if these are
7256). Significant gca effects in negative direction
exploited through conventional selection methods.
were observed in PRG 117 (-1.70), PRG 137 (-0.70),
GCA effects would be more stable as compared to
PRG 142 (-0.57) and PRG 120 (-0.47). Six parents
SCA effects. In general, additive effects are mainly
showed significant gca effects out of which two
due to polygenes producing fixable effects and
were in negative direction for the trait node number
indicate the capacity of variety in relation to all
to first female flower. The maximum value for gca
other varieties, it was crossed with. High GCA
effects was recorded in PRG 142 (-1.13) followed by
effects of a parent is a function of breeding value and
PRG 137 (-0.49). In case of days taken to first fruit
hence due to additive gene effect and/or additive
156