Hostname: page-component-8448b6f56d-xtgtn Total loading time: 0 Render date: 2024-04-24T10:44:30.547Z Has data issue: false hasContentIssue false
  • English
  • Français

Inter-plot competition in variety trials of field beans (Vicia faba L.)

Published online by Cambridge University Press:  27 March 2009

R. A. Kempton  and
G. Lockwood
R. A. Kempton
Affiliation:
Plant Breeding Institute, Trumpington, Cambridge
G. Lockwood
Affiliation:
Plant Breeding Institute, Trumpington, Cambridge
Get access Rights & Permissions [Opens in a new window]

Summary

Four trials were carried out to investigate the effect of inter-plot competition on seed yield and plant height of field beans using experimental designs balanced for neighbours. One trial tested four varieties ranging in final height from 25 to 100 cm and sown in four-row plots with 30 cm spacing between rows and one blank row between plots. When grown between plots of a dwarf variety, the plot yield of the tallest variety was increased by 20% compared with its pure stand yield: a complementary reduction in yield was shown by the dwarf variety when grown between plots of the tall. The effect on the yield of the inner rows of the plot was somewhat smaller than that of the outer rows but still significant. Another trial with six commercial varieties differing in final height by less than 15 cm showed no differential effects of inter-varietal competition on yield. In two trials with six varieties of widely differing heights planted with 50 cm spacing between rows, but no gap between plots, plot yield was strongly affected by the neighbouring variety in the trial with single-row plots, while yields from the four-row trial showed a large interaction between variety and inner and outer row position, again indicative of inter-variety competition. The yield response to competition could be described by a common linear regression on the excess height of plot neighbours: there was little evidence of varietal differences in sensitivity or aggressiveness.

Plant height showed a positive response to height of plot neighbours in all four trials, whilst in the single-row trial, the ratio of grain yield to total dry-matter production (harvest index) was negatively related to excess height of neighbours.

The results suggest that, when testing varieties differing in height by more than 20 cm, at least two buffer rows, e.g. six-row plots with the centre two rows harvested, are required to obtain a true comparison of pure-stand yield. Alternatively, when this procedure would result in an unacceptable use of resources, one of the statistical models adapted in this paper may be used to adjust variety yields for pure stands.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 103 , Issue 2 , October 1984 , pp. 293 - 302
Copyright
Copyright © Cambridge University Press 1984

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

Austin, R. B. & Blackwell, R. D. (1980). Edge and neighbour effects in cereal yield trials. Journal of Agricultural Science, Cambridge 94, 731–734.CrossRefGoogle Scholar
Bond, D. A., Fyfe, J. L. & Toynbee-Clarke, G. (1966). Yields of mixtures of single-cross hybrid field beans (Viciafaba L.) with one of the parental inbred lines. Journal of Agricultural Science, Cambridge 67, 235–237.Google Scholar
Cannell, M. G. R., Njuguna, C. K., Ford, E. D., Smith, R. & Ross-Parker, H. M. (1977). Variation in yield among competing individuals within mixed genotype stands of tea: a selection problem. Journal of Applied Ecology 14, 969–985.CrossRefGoogle Scholar
Finney, D. J. & Outhwaite, A. D. (1956). Serially balanced sequences in bioassay. Proceedings of the Royal Society B 145, 493–507.Google ScholarPubMed
Fischer, R. A. (1979). Are your results confounded by intergenotypic competition? In Proceedings of the Vth International Wheat Genetics Symposium, vol. 2, pp. 767–777. New Delhi, 1978.Google Scholar
Freeman, G. H. (1979). Some two-dimensional designs balanced for nearest neighbours. Journal of the Royal Statistical Society B 41, 88–95.Google Scholar
Gomez, K. A. (1972). Border effects in rice experimental plots. II. Varietal competition. Experimental Agriculture 8, 295–298.CrossRefGoogle Scholar
Jensen, N. F. & Federer, W. T. (1964). Adjacent row competition in wheat. Crop Science 4, 641–645.CrossRefGoogle Scholar
Kempton, R. A. (1982). Adjustment for competition between varieties in plant breeding trials. Journal of Agricultural Science, Cambridge 98, 599–611.CrossRefGoogle Scholar
Le Clerg, E. L., Leonard, W. H. & Clark, A. G. (1962). Field Plot Technique. Minneapolis: Burgess.Google Scholar
Omar, M. & Hawtin, G. (1980). Plot technique studies on Faba beans. III. Border effects for different plot designs. Faba Bean Information Service 2, 15–16.Google Scholar
Sjödin, S. (1971). Induced morphological variation in Viciafaba L. Hereditas 67, 155–180.CrossRefGoogle Scholar
Thompson, R. & Taylor, H. (1982). Prospects for Vicia faba L. in Northern Europe. Outlook on Agriculture 11, 127–133.CrossRefGoogle Scholar
Williams, E. J. (1962). The analysis of competition experiments. Australian Journal of Biological Science 15, 509–525.CrossRefGoogle Scholar
Williams, R. M. (1952). Experimental designs for serially correlated observations. Biometrika 39, 152–167.CrossRefGoogle Scholar