Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-03T05:53:13.888Z Has data issue: false hasContentIssue false

Interpopulational and intervarietal F1 hybrids in Lolium perenne: performance in field sward conditions

Published online by Cambridge University Press:  27 March 2009

C. A. Foster
Affiliation:
Plant Breeding Division, Ministry of Agriculture for Northern Ireland, Loughgall, Go. Armagh.

Summary

Fifteen intervarietal F1hybrids and their parents were evaluated in two field sward trials, representing three levels of management intensity each maintained over a 2-year harvest period. The trials were sown in different years and at different sites. Several hybrids exhibited significant levels of heterosis for total annual dry-matter yield – up to 5–5 % mid-parent and up to 3–6 % higher-parent heterosis. Within individual trials mid-parent heterosis up to 8% was found, while at particular harvests over 25% heterosis was not uncommon. Comparisons made of performance in swards, simulated swards and spaced-plant conditions showed that genetic differences found maximum expression in non-competitive conditions. This was greatly reduced in simulated swards and further suppressed in sown swards in the field. Expression of heterosis was highly specific to the conditions in which it was tested, although the two hybrids most heterotic as spaced plants were also significantly heterotic in field swards.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1973

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Foster, C. A. (1971 a). Interpopulational and intervarietal hybridization in Lolium perenne:heterosis under non-competitive conditions. J. agric. Sci., Camb. 76, 107.CrossRefGoogle Scholar
Foster, C. A. (1971 b). A study of the theoretical expectation of F1hybridity resulting from bulk interpopulational hybridization in herbage grasses. J. agric. Sci., Camb. 76, 295.CrossRefGoogle Scholar
Foster, C. A. (1971 c). Interpopulational and intervarietal F1hybridity in Lolium perenne: heterosis under simulated-sward conditions. J. agric. Sci., Camb. 76, 401.CrossRefGoogle Scholar
Foster, C. A. Prospects for the development of F1 hybrid varieties of perennial ryegrass, Lolium perenne. J. agric. Sci., Camb.(In the Press.)Google Scholar
Foster, C. A. & Wright, C. E. (1968). Sample size and sampling intensity in relation to the precision of small-plot herbage sward trials. J. agric. Sci., Camb. 70, 19.CrossRefGoogle Scholar