(go to KOMUGI Home) (go to WIS List) (go to NO.72 Contents)


Per cent heterosis (over mid-parent) ranged from -30.2 to 16.7 for NT, -13.8 to 31.2 for NG, -5.4 to 13.2 for GW and -31.9 to 36.9 for GY in normal environment. Likewise, in stress environment such a range was from -29.0 to 23.8 for NT, -26.8 to 22.1 for NG, -9.7 to 16.5 for GW and -35.4 to 56.4 for GY. Highest heterosis 36.9 and 56.4 per cent for GY was expressed by hybrids WL 711 x HD 2122 and UP 262 x HD 2122 in normal and stress environments, respectively. Out of 36 hybrids, only 3, 10, 16 and 13 in normal environment and 1, 7, 16 and 11 in stress environment showed significant heterosis for NT, NG, GW and GY, respectively. Majority of hybrids, exhibiting significant heterosis, manifested negative heterosis and narrow range for NT in both the environmets. Heterosis for GY, therefore, could be attributed mainly to GW and/or NG. Intercluster hybrids were more frequent among hybrids with significant heterosis though the expression of heterosis was better in intracluster hybrids. Lack of heterosis in highly divergent intercluster hybrids may be attributed to unfavourable gene interactions or intercancellation of favourable gene effects, whereas high heterosis in intra-/intercluster hybrids with medium to low genetic divergence may be explained on the basis of complementary gene effects.


References

Arunachalam V, Bandyopadhyay A, Nigam. SN and Gibbons RW (1984) Heterosis in relation to genetic divergence and specific combining ability in groundnut (Arachis hypogaea L). Euphytica 33: 33-39.

Behl RK and Singh VP (1986) Genetic divergence in some triticales strains and their hybrids. Wheat Information Service 61 & 62: 46-50.

Behl RK, Singh VP and Paroda RS (1985) Genetic divergence in relation to heterosis and specific combining ability in triticale. Indian J Genet 45: 368-375.

Chaudhary BD and Singh VP (1975) Genetic divergence in some Indian and exotic barley varieties and their hybrids. Indian J Genet 35: 409-412.

Jatasra DS and Paroda, RS (1978) Genetic divergence in wheat under different environmental conditions. Cereal Res Communication 6: 307-317.

Rao CR (1952) Advanced Statistical Methods in Biometric Research. John Wiley and Sons Inc., New York.

Somayajulu PLN, Joshi AB and Murty BR (1970) Genetic divergence in wheat. Indian J Genet 30: 47-58.

Srivastava PSL and Arunachalam V (1977) Heterosis as a function of genetic divergence in triticale. Z Pflanzenzuchtung 78: 269-275.

<--Back

(go to KOMUGI Home) (go to WIS List) (go to NO.72 Contents)