Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-24T04:04:19.305Z Has data issue: false hasContentIssue false
  • English
  • Français

Yields and tiller numbers of four perennial ryegrass varieties grown as monocultures and certain mixtures in micro plots

Published online by Cambridge University Press:  27 March 2009

A. J. Thomson
A. J. Thomson
Affiliation:
Plant Breeding Institute, Trumpington, Cambridge
Get access Rights & Permissions [Opens in a new window]

Summary

Four perennial ryegrass varieties, S.24, S.321, S.23 and Vertas Hardgrazing, were grown in micro plots containing 30 plants each at a spacing of 5 cm apart. Monocultures and four of the possible six binary mixtures between the varieties were grown in a randomized block design with four replicates. The data recorded comprised dry-matter yields and tiller numbers, and the components of the mixtures were harvested separately. The data were based on both whole plots, to give total production of mixtures and monocultures, and half plots, to give the contribution of mixture components to total mixture production. Four harvests were obtained during 1968, and the data from these were analysed separately and summed to provide the annual total data.

Mixtures and monocultures did not differ significantly for annual total dry-matter yield or for dry-matter yield at the separate harvests. However, differences in drymatter yields between monocultures and between mixtures were detected at some harvests. Within mixtures, significant differences between some of the respective components were found at certain harvests, but these were not obtained for the annual total data.

The stability of monocultures and mixtures was investigated by a regression technique and considered in the context of the environments used. This technique revealed that there was a specific mixture effect whereby the mixture (S.24 + S.23) differed significantly from all other treatments.

Significant differences between monocultures for fertile and sterile tiller numbers were detected. Between mixtures there were differences for fertile tiller numbers, and within mixtures certain of the components differed for fertile, sterile and total tiller numbers.

The relationship between dry-matter yield and tiller numbers was investigated by regression analyses over all treatments and for monocultures and mixtures separately. Significant differences between the slopes of the regression lines and zero and between the slopes of the regression lines themselves were obtained.

Possible reasons for the differences recorded both between and within monocultures and mixtures are considered and related to the competitive relations existing in the trial.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 73 , Issue 3 , December 1969 , pp. 321 - 328
Copyright
Copyright © Cambridge University Press 1969

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

REFERENCES

Alcock, M. B. & Morgan, E. W. (1966). The effect of frequency of defoliation on the yield of mixtures of S.22 (diploid) and Tetra (tetraploid) Italian ryegrass in early establishment. J. Br. Grassld Soc. 21, 62–4.CrossRefGoogle Scholar
Bergh, J. P. Van Den (1968). An analysis of yields of grasses in mixed and pure stands. Versl. landbouwk. Onderz. 714, (1968).Google Scholar
Cowling, D. W. & Lockyer, D. R. (1968). A comparison of the yield of three grass species at various levels of nitrogenous fertiliser sown alone or in a mixture. J. agric. Sci., Gamb. 71, 127–36.CrossRefGoogle Scholar
Donald, C. M. (1956). Competition among pasture plants. Proc. 7th int. Grassld Congr. Palmerston North, N.Z. pp. 80–91.Google Scholar
Donald, C. M. (1963). Competition among crop and pasture plants. Adv. Agron. 15, 1–118.CrossRefGoogle Scholar
England, F. (1965). Interactions in mixtures of herbage plants. Rep. Scott. PI. Breed. Stn. 1965, 125–49.Google Scholar
England, F. (1968). Competition in mixtures of herbage grasses. J. appl. Ecol. 5, 227–42CrossRefGoogle Scholar
Finlay, K. W. & Wilkinson, G. N. (1963). The analysis of adaptation in a plant breeding programme. Aust. J. agric. Res. 14, 742–54.CrossRefGoogle Scholar
Gardner, A. L. & Hunt, I. V. (1963). Inter-varietal competition in perennial ryegrass swards. J. Br. Grassld Soc. 18, 285–91.CrossRefGoogle Scholar
Lazenby, A. & Rogers, H. H. (1962). Selection criteria in grass breeding. I. J. agric. Sci., Camb. 59, 51–66.Google Scholar
Norrington-Davies, J. (1968). Diallel analysis of competition between grass species. J. agric. Sci. Camb. 71, 223–31.CrossRefGoogle Scholar
Perkins, J. M. & Jinks, J. L. (1968). Environmental and genotype-environmental components of variability. III. Multiple lines and crosses. Heredity, Lond. 23, 339–56.CrossRefGoogle Scholar
Rasmusson, D. C. (1968). Yield and stability of yield in barley populations. Crop Sci. 8, 600–2.CrossRefGoogle Scholar
Rhodes, I. (1968a). The growth and development of some grass species under competitive stress. I. Competition between seedlings and between seedlings and established plants. J. Br. Grassld Soc. 23, 129–36.CrossRefGoogle Scholar
Rhodes, I. (1968b). The growth and development of some grass species under competitive stress. II. Regrowth, floral development and seasonal production. J. Br. Grassld Soc. 23, 247–58.CrossRefGoogle Scholar
Rhodes, I. (1968 c). Yield of contrasting ryegrass varieties in monoculture and mixed culture. J. Br. Grassld Soc. 23, 156–8.CrossRefGoogle Scholar
Rogers, H. H. & Lazenby, A. (1966). The evaluation of grasses in micro plots. J. agric. Sci., Camb. 66, 147–51.CrossRefGoogle Scholar
Whittington, W. J. & O'Brien, T. A. (1968). A comparison of yields from plots sown with a single species or a mixture of grass species. J. appl. Ecol. 5, 209–13.CrossRefGoogle Scholar
Wit, C. T. De (1960). On competition. Versl. landbouwk. Onderz. 66, 1–82.Google Scholar
Yamada, T. & Horiuchi, S. (1960). On the bias of quantitative characters and the change in their distribution in a population due to interplant competition. Proc. 8th int. Grassld Gongr. Reading, U.K. 1960, pp. 297–301.Google Scholar