Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-27T19:56:45.498Z Has data issue: false hasContentIssue false
  • English
  • Français

Reflexion and absorption of solar radiation by flowering canopies of oil-seed rape (Brassica napus L.)

Published online by Cambridge University Press:  27 March 2009

D. J. Yates  and
M. D. Steven
D. J. Yates
Affiliation:
Department of Physiology and Environmental Science, University of Nottingham School of Agriculture, Sutton Bonington, Loughborough, Leicestershire
M. D. Steven
Affiliation:
Department of Physiology and Environmental Science, University of Nottingham School of Agriculture, Sutton Bonington, Loughborough, Leicestershire
Get access Rights & Permissions [Opens in a new window]

Summary

Flowers were present over a period of approximately 6 weeks in 12 varieties of oil-seed rape. A linear relationship was found between flower cover (maximum 74%) and photon reflectivity (400–700 nm) which increased from around 0·047 during vegetative growth to 0·195 for a canopy in full flower. Reflexion and absorption of photons by flowers reduced light available to the leaf canopy and immature pods. Spectral measurements indicate that flowering canopies reflect substantially more radiation and absorb less than vegetative canopies between 500 and 700 nm but reflect less and absorb slightly more between 400 and 500 nm.

Seed yield was not strongly correlated with estimates of the radiation absorbed by the leaf canopy under the flower layer. It appears that whilst increased flower density in a canopy might be expected to contribute to increased seed yield, increased reflectivity by petals may have a negative effect on yield. Breeding for reduced petal size or for apetalous lines may result in improved yields by producing more efficient light distribution within the canopy.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 109 , Issue 3 , December 1987 , pp. 495 - 502
Copyright
Copyright © Cambridge University Press 1987

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

Allen, E. J. & Scott, R. K. (1980). An analysis of growth of the potato crop. Journal of Agricultural Science, Cambridge 94, 583–606.CrossRefGoogle Scholar
Gates, D. M., Keegan, H. N., Schleter, J. C. & Weidner, V. R. (1965). Spectral properties of plants. Applied Optics 4, 11–20.CrossRefGoogle Scholar
McCartney, H. A. & Unsworth, M. H. (1978). Spectral distribution of solar radiation. I. Direct radiation. Quarterly Journal of the Royal Meteorological Society 104, 699–718.CrossRefGoogle Scholar
McCree, K. J. (1972). Test of current definitions of photosynthetically active radiation against leaf photo-synthesis data. Agricultural Meteorology 10, 443–453.CrossRefGoogle Scholar
McCree, K. J. (1981). Photosynthetically active radiation. In Physiological Plant Ecology (ed. Lange, D. L., Nobel, P. S., Osmond, C. B. and Ziegler, H.). Encyclopedia of Plant Physiology, New Series, 12A, pp. 41–55.Google Scholar
Mendham, N. J. & Scott, R. K. (1975). The limiting effect of plant size at inflorescence initiation on subsequent growth and yield of oil-seed rape (Brassica napus). Journal of Agricultural Science, Cambridge 84, 487–502.CrossRefGoogle Scholar
Mendham, N. J., Shipway, P. A. & Scott, R. K. (1981 a). The effects of delayed sowing and weather on growth, development and yield of winter oil-seed rape (Brassica napus). Journal of Agricultural Science, Cambridge 96, 389–416.CrossRefGoogle Scholar
Mendham, N. J., Shipway, P. A. & Scott, R. K. (1981 b). The effects of seed size, autumn nitrogen and plant population density on the response to delayed sowing in winter oil-seed rape (Brassica napus). Journal of Agricultural Science, Cambridge 96, 417–428.CrossRefGoogle Scholar
Monteith, J. M. (1973). Principles of Environmental Physics. London: Arnold.Google Scholar
Monteith, J. M. (1977). Climate and the efficiency of crop production in Britain. Philosophical Transactions of the Royal Society of London B 281, 277–294.Google Scholar
Smith, H. (1973). Light quality and germination. Ecological implications. In Seed Ecology (ed. Heydecker, W.), pp. 219–31. London: Butterworth.Google Scholar