Cucurbit Genetics Cooperative Report 17:132-134 (article 40) 1994
V.S. Devadas; Seemahthini Ramadas
College of Horticulture, Kerala Agricultural University, Vellanikkara, Trissur-680 645, India; Horticulture College and Research Institute, Tamil Nadu Agricultural University, Coimbatore-641 003, India
All parts of the bitter gourd plant are bitter in taste except the ripe aril covering the seed. The bitter principals are designated as Momordicosides, which are glycosides of triterpinoids with a cucurbitane skeleton (3). Cucurbitane triterpenes have received attention because of their cytotoxic, anticancer and other biological activities. Information on heterosis and combining ability for the specific biter principals in bitter gourd are lacking.
Triterpinoid content of fruits of twelve morphologically and geographically diverse bitter gourd parents were analyzed (2) as a part of a 12 x 12 diallel experiment. Fruits of 12 hybrid combinations involving four parents (P3 and P5 with the lowest content and P7 and P12 with the highest content) were also analyzed for triterpinoid content, and heterosis and combining ability were estimated. Mean triterpinoid content of the 12 parents and the 12 hybrids, and heterosis (di = relative heterosis based on mid parent value; dii = heterosis based on the higher parent value; and diii = standard heterosis based on the value of standard parent (i.e. P8)) observed are furnished in Table 1.
Triterpinoid content of the parents differed significantly. The highest amounts were observed in P7 and P12, and the lowest in P3 and P5. The positive heterosis (di, dii and diii) was expressed by P5 x P3 and P7 x P12; and the lowest (negative) heterosis was seen in P5 x P7 and its reciprocal combination. In general, high x high and low x low parental combinations exhibited maximum positive heterosis and the low x high or high x low combinations exhibited maximum negative heterosis.
General and specific combining ability effects (GCA, SCA) were statistically significant and are presented in Table 2. A high proportion of GCA:SCA (1.413:1.00) was observed indicating preponderance of additive gene action. P7 and P12 had significant positive GCA effects, and the maximum triterpinoid content (per se values as well as heterosis) of P7 x P12 indicated additive x additive epistatic interaction. Additive, dominance, and additive x dominance gene actions in controlling the total crude bitter contents of bitter gourd fruits have been reported earlier (1). Since both additive and non-additive gene actions are observed, the appropriate breeding method would be reciprocal recurrent selection.
This work is part of the Ph.D. Thesis submitted by the first author to the Tamil Nadu Agricultural University, Coimbatore, in 1993.
The first author is grateful to the Indian Council of Agricultural Research, New Delhi for granting him a Senior Fellowship during the period of the study.
Table 1. Mean triterpinoid content (mg/g) on dry weight basis of fruits and heterosis.
For 12 Parents |
For 12 Hybrids |
||||||
Parent S1. No. |
Name |
Mean triterpinoids (mg/g) |
Combination |
Mean triterpinoids (mg.g) |
Heterosis |
||
di |
dii |
diii |
|||||
P1 | ‘Pusa Do Mausami’ | 2.333 | P3 x P5 | 0.999 | -7.74 | -20.79 | -56.72 |
P2 | ‘MDu 1’ | 3.438 | P3 x P7 | 2.147 | -2.08 | -56.22** | -7.04 |
P3 | MC 13 | 0.905 | P3 x P12 | 1.333 | -57.08** | -74.10** | -50.94 |
P4 | “Priya’ | 2.500 | P5 x P3 | 6.333 | 484.56** | 401.88** | 174.18** |
P5 | ‘Arka Harit’ | 1.262 | P5 x P7 | 0.929 | -69.88** | -81.07** | -59.80** |
P6 | MC 36 | 2.024 | P5 x P12 | 2.314 | -17.90 | -47.11** | 0.19 |
P7 | MC 41 | 4.905 | P7 x P3 | 1.457 | -49.83 | -70.29** | -36.91 |
P8 | ‘Co 1’ | 2.095 | P7 x P5 | 1.186 | -61.55** | -75.83** | -48.67 |
P9 | MC 78 | 3.367 | P7 x P12 | 9.381 | 102.16** | 91.26** | 306.12** |
P10 | ‘Coimbatore Long Green’ | 1.595 | P12 x P3 | 3.038 | 15.05 | -30.58* | 31.52 |
11 | Kau Cluster MC 84 | 2.524 | P12 x P5 | 4.195 | 48.82** | -4.13 | 81.62** |
P12 | White Long | 4.376 | P12 x P7 | 4.376 | -55.16** | -57.57** | -9.91 |
SE(+) | 0.239 | SE (+) | 0.461 | *Significant at 5% level | |||
C.D. (P = 0.05) | 0.701 | C.D. (P=) .05 | 1.332 | **Significant at 1% level |
Table 2. General and specific combining ability effects for triterpinoid content of fruits.
Female/Male |
P3 |
P5 |
P7 |
P12 |
P3 | -0.800** | 2.158** | -0.771** | 0.976** |
P5 | -2.667** | -0.605** | -1.712** | -2.021** |
P7 | -0.345 | -0.129 | 0.459** | 1.411** |
P12 | -0.952** | -0.941 | 3.650** | 0.947** |
SE (+) |
CD (P = 0.05) |
|
GCA | 0.141 | 0.41 |
SCA | 0.258 | 0.73 |
reciprocal | 0.326 | 0.94 |
Literature Cited
- Abul Vehab, M. 1989. Homostastic analysis of components of genetic variance andinheritance of fruit color, shape and bitterness in bitter gourd (Momordica charantia Linn.). Ph.D. Thesis. Keerala Agricultural University, Vellankkara-680654, India.
- Chandravadana, M.V. 1987. Identification of triterpinoid feeding deterrent of red pumpkin beetles from Momordica charantia. J. Chem. Ecol;. 13(7):1689-1694.
- Chandravadana, M.V. and M. Subhas Chander. 2990. Subcellular distribution of Momordicine II in Momordica charantia leaves. Indian J. Exp. Biol. 28:185-186.