Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-25T19:30:50.119Z Has data issue: false hasContentIssue false

Number of kernels in wheat crops and the influence of solar radiation and temperature

Published online by Cambridge University Press:  27 March 2009

R. A. Fischer
Affiliation:
CSIRO Division of Plant Industry, G.P.O. Box 1600, Canberra 2601, Australia

Summary

The number of kernels per m2 (K) in well managed and watered wheat crops was studied using results of experiments in Mexico and Australia in which short spring wheat cultivars were subjected to independent variation in radiation, largely via artificial shading, and in temperature. Also crops subjected to differences in weather (year), sowing date and location within Mexico, revealed responses to the natural and simultaneous variation which occurs in radiation and temperature. Responses in K were interpreted in terms of spike dry weight at anthesis (g/m2) and number of kernels per unit of spike weight.

K was linearly and most closely related to incident solar radiation in the 30 days or so preceding anthesis, herein termed the spike growth period; for the cultivar Yecora 70 with full ground cover the slope was 19 kernels/MJ. This response seemed largely due to a linear response of crop growth rate to intercepted solar radiation. The proportion of dry weight increase partitioned to the spike increased somewhat with reduced radiation. Also increasing temperature in the range 14–22 °C during this period reduced K (slope approximately 4% per CC at 15 °C). The cause appeared to be lower spike dry weight due to accelerated development. The number of kernels per unit spike weight at anthesis was little affected by radiation or temperature, and averaged 78±2/g for the cultivar Yecora 70.

With natural variation in radiation and temperature, K was closely and linearly correlated with the ratio of mean daily incident or intercepted radiation to mean temperature above 4·5 °C in the 30 days preceding anthesis. As this ratio, termed the photothermal quotient, increased from 0·5 to 2·0 MJ/m2/day/degree, K increased from 70 to 196 × 102/m2. These responses of K to weather, sowing date and location were closely associated with variation in spike dry weight.

It was concluded that the ratio of solar radiation to temperature could be very useful for estimating K in wheat crop models. Also the analysis of K determination in terms of spike dry weight appeared promising, and suggests that wheat physiologists should place greater emphasis on the growth period immediately before anthesis.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1985

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

Angus, J. F., Mackenzie, D. H., Morton, R. & Schafer, C. A. (1981). Phasic development in field crops. II. Thermal and photoperiodic responses of spring wheat. Field Crops Research 4, 269283.CrossRefGoogle Scholar
Austin, R. B. & Jones, H. G. (1976). The physiology of wheat. Plant Breeding Institute. Annual Report 1975. pp. 2073.Google Scholar
Borojevic, S. & Williams, W. A. (1982). Genotype × environment interactions for leaf area parameters and yield components and their effects on wheat yields. Crop Science 22, 10201025.CrossRefGoogle Scholar
Buck, S. F. (1961). The use of rainfall, temperature, and actual transpiration in some crop-weather investigations. Journal of Agricultural Science, Cambridge 57, 355365.CrossRefGoogle Scholar
Cackett, K. E. & Wall, P. C. (1971). The effect of altitude and season length on the growth and yield of wheat (Triticum aestivum) in Rhodesia. Rhodesian Journal of Agricultural Research 9, 107120.Google Scholar
Desjardins, R. L. & Ouellet, C. E. (1980). Determination of the importance of various phases of wheat growth on final yield. Agricultural Meteorology 22, 129136.CrossRefGoogle Scholar
Evans, L. T. (1978). The influence of irradiance before and after anthesis on grain yield and its components in microcrops of wheat grown in a constant daylength and temperature regime. Field Crops Research 1, 519.CrossRefGoogle Scholar
Fischer, R. A. (1975). Yield potential of dwarf spring wheat and the effect of shading. Crop Science 15, 607613.CrossRefGoogle Scholar
Fischer, R. A. (1983). Growth and yield of wheat. In Proceedings Symposium on Potential Productivity of Field Crops under Different Environments, International Rice Research Institute, Los Baños, Philippines, September 1980, pp. 129154.Google Scholar
Fischer, R. A. & Laing, D. R. (1976). Yield potential in a dwarf spring wheat and response to crop thinning. Journal of Agricultural Science, Cambridge 87, 113122.CrossRefGoogle Scholar
Fischer, R. A. & Maurer, R. (1976). Crop temperature modification and yield potential in a dwarf spring wheat. Crop Science 16, 855859.CrossRefGoogle Scholar
Fischer, R. A. & Stockman, Y. M. (1980). Kernel number–per spike in wheat (Triticum aestivum L.).Responses to preanthesis shading. Australian Journal of Plant Physiology 7, 169180.Google Scholar
Friend, D. J. C., Fisher, J. E. & Helson, V. A. (1963). The effect of light intensity and temperature on floral initiation and inflorescence development in Marquis wheat. Canadian Journal of Botany 41, 16631674.Google Scholar
Gallagher, J. N. (1979). Ear development: processes and prospects. In Crop Physiology and Cereal Breeding. (Proceedings of Eucarpia Workshop, Wageningen, 1978) (ed. Spiertz, J. H. J. and Kramer, Th.), pp. 39.Google Scholar
Gallagher, J. N. & Biscoe, P. V. (1978). Radiation absorption, growth and yield of cereals. Journal of Agricultural Science, Cambridge 91, 4760.CrossRefGoogle Scholar
Krenzer, E. G. Jr & Moss, D. N. (1975). Carbon dioxide enrichment effects upon yield and yield components in wheat. Crop Science 15, 7174.CrossRefGoogle Scholar
McCree, K. J. (1974). Equations for the rate of dark respiration of white clover and grain sorghum, as functions of dry weight, photosynthetic rate, and temperature. Crop Science 14, 509514.CrossRefGoogle Scholar
Michaels, P. J. (1981). The climatic sensitivity of ‘Green Revolution’ wheat culture in Sonora, Mexico. Environmental Conservation 8, 307311.CrossRefGoogle Scholar
Midmore, D. M., Cartwright, P. M. & Fischer, R. A. (1982). Wheat in tropical environments. I. Phasic development and spike size. Field Crops Research 5, 185200.CrossRefGoogle Scholar
Midmore, D. M., Cartwright, P. M. & Fischer, R. A. (1984). Wheat in tropical environments. II. Crop growth and grain yield. Field Crops Research 8, 207227.CrossRefGoogle Scholar
Nix, H. A. (1975). The Australian climate and its effects on grain yield and quality. In Australian Field Crops. Vol. I. Wheat and Other Temperate Cereals (ed. Lazenby, A. and Matheson, E. M.), pp. 183226. Sydney: Angus and Robertson.Google Scholar
Nix, H. A. (1976). Climate and crop productivity in Australia. In Climate and Rice (ed. Yoshida, S.). International Rice Research Institute, Los Baños, The Philippines, pp. 495507.Google Scholar
Pendleton, J. W. & Weibel, R. O. (1965). Shading studies on winter wheat. Agronomy Journal 57, 592593.CrossRefGoogle Scholar
Peters, D. B., Pendleton, J. W., Hageman, R. H. & Brown, C. M. (1971). Effect of night air temperature on grain yield of corn, wheat and soybeans. Agronomy Journal 63, 809.Google Scholar
Puckridge, D. W. & Donald, C. M. (1967). Competition among wheat plants sown at a wide range of densities. Australian Journal of Agricultural Research 18, 193211.CrossRefGoogle Scholar
Rahman, M. S. (1977). Determination of spikelet number in wheat. Ph.D. thesis, University of Melbourne, 122 pp.Google Scholar
Rawson, H. M. (1970). Spikelet number, its control and relation to yield per ear in wheat. Australian Journal of Biological Sciences 23, 115.CrossRefGoogle Scholar
Rawson, H. M. & Bagga, A. K. (1979). Influence of temperature between floral initiation and flag leaf emergence on grain number in wheat. Australian Journal of Plant Physiology 6, 391400.Google Scholar
Richardson, C. W. (1982). Dependence structure of daily temperature and solar radiation. Transactions of the American Society of Agricultural Engineers 25, 735739.Google Scholar
Robertson, G. W. (1968). A biometeorological time scale for a cereal crop involving day and night temperatures and photoperiod. International Journal of Biometeorology 12, 191223.CrossRefGoogle Scholar
Saini, H. S. & Aspinall, D. (1982). Sterility in wheat (Triticum aestivum L.) induced by water deficit or high temperature: possible mediation by abscisic acid. Australian Journal of Plant Physiology 9, 529537.Google Scholar
Single, W. V. & Marcellos, H. (1974). Studies of frost injury to wheat. IV. Freezing of ears after emergence from the leaf sheath. Australian Journal of Agricultural Research 25, 679686.CrossRefGoogle Scholar
Smika, D. E. & Shawcroft, R. W. (1980). Preliminary study using a wind tunnel to determine the effect of hot wind on a wheat crop. Field Crops Research 3, 129135.CrossRefGoogle Scholar
Sofield, I., Evans, L. T., Cook, M. G. & Wardlaw, I. F. (1977). Factors influencing the rate and duration of grain filling in wheat. Australian Journal of Plant Physiology 4, 785797.Google Scholar
Stockman, Y. M., Fischer, R. A. & Brittain, E. G. (1983). Assimilate supply and floret development within the wheat spike. Australian Journal of Plant Physiology 10, 585594.Google Scholar
Takeda, G. (1978). Photosynthesis and dry matter reproduction system in winter cereals. I. Photosynthetic function. Bulletin of the National Institute of Agricultural Sciences Series D. 29, pp. 165.Google Scholar
Thompson, L. M. (1975). Weather variability, climatic change and grain production. Science 188, 525541.CrossRefGoogle ScholarPubMed
Thorne, G. N. (1974). Physiology of grain yield of wheat and barley. Report Rothamsted Experimental Station for 1973, Part 2, pp. 525.Google Scholar
Wall, P. C. (1979). An analysis of factors limiting grain number and yield of spring wheat in a low latitude environment. Ph.D. thesis, University of Reading.Google Scholar
Wardlaw, I. F. (1970). The effect of temperature on kernel development in cereals. Australian Journal of Agricultural Research 29, 205223.Google Scholar
Warrington, I. J., Dunstone, R. L. & Green, L. M. (1977). Temperature effects at three developmental stages on the yield of the wheat ear. Australian Journal of Agricultural Research 28, 1127.CrossRefGoogle Scholar
Welbank, P. J., Witts, K. J. & Thorne, G. N. (1968). Effect of radiation and temperature on efficiency of cereal leaves during grain growth. Annals of Botany 32, 7995.Google Scholar
Willey, R. W. & Holliday, R. (1971). Plant population, shading and thinning studies in wheat. Journal of Agricultural Science, Cambridge 77, 453461.Google Scholar