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The association between altitude, environmental variables, maize growth and yields in Kenya

  • P. J. M. Cooper (a1)

Summary

A Kenya Highland maize was planted at three altitudes, 1268, 1890 and 2250 m. Development rate, dry-matter accumulation and leaf area production were recorded during vegetative growth, together with grain formation and dry-matter accumulation in the primary cob. Rainfall, insolation, soil and air temperatures were continuously recorded at all sites. Maize developed faster at low warm altitudes, the rate being dependent on soil and air temperature. During vegetative growth, this relationship could be satisfactorily explained by an integrated temperature, but during the reproductive phase, some allowance had to be made for over optimal temperatures at low warm altitudes. Altitude had little effect on crop leaf area at any particular development stage, but leaf area production rates were closely related to leaf emergence rates. Before establishment of complete ground cover, large differences in dry-matter accumulation rates were observed which appeared related to rate of leaf area production. Once full ground cover was established, crop growth rates became much more similar. Potential number of grains per embryonic primary cob was greatest at low altitudes, but the final number of grains per cob at harvest was greatest at high altitudes. Rate of increase of grain weight was constant and very similar at all sites until growth stopped abruptly at 69, 83 and 96 days after tasselling at low, medium and high altitudes respectively. Rate of accumulation and partition of total dry matter in the primary cobs was similar at all sites, but owing to greater duration of development at high altitudes, dry matter per cob increased with altitude. Large yield differences were found at harvest, yield decreasing with decreasing altitude. Yield differences were mainly due to variations in number of grains per plant, although grain size also contributed. In this and other trials it was shown that the number of grains per plant at harvest was closely related to the mean thermal growth rate (expressed in units of g/plant/growing degree day) during the grain site initiation period.

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Allan, A. Y. (1972). The influence of agronomic factors on maize yields in Western Kenya with special reference to time of planting. Ph.D. thesis, University of East Africa.
Biscoe, P. V. & Gallagher, J. N. (1977). Weather, dry matter production and yield. In Environmental Effects on Crop Physiology (ed. Landsberg, J. J. and Cutting, C. V.). London: Academic Press.
Brouwer, R., Kleinendorst, R. & Locher, J. (1970). Growth response of maize plants to temperature. In Plant Response to Climatic Factors, pp. 169174. Paris: UNESCO.
Coligado, M. C. & Brown, D. M. (1974). Response of corn (Zea maysL.) in the pre-tassel initiation period to temperature and photoperiod. Agricultural Meteorology 14, 357367.
Cooper, P. J. M. (1973). Soil physical conditions under maize, grass and bare fallow in the Highlands of Kenya. Proceedings of Technical Conference, Nairobi. W.M.O. Report, no. 389, pp. 169186.
Cooper, P. J. M. & Law, R. (1977). Soil temperature and its association with maize yield variations in the Highlands of Kenya. Journal of Agricultural Science Cambridge 89, 355363.
Cooper, P. J. M. & Law, R. (1978). Enhanced soil temperature during very early growth and its association with maize development and yield in the Highlands of Kenya. Journal of Agricultural Science Cambridge 89, 569577.
Darrah, L. L. & Penny, L. H. (1974). Altitude and environmental responses of entries in the 1970–71 East African maize variety trial, East African Agricultural and Forestry Journal 40, 7788.
Duncan, W. G., Davis, D. R. & Chapman, W. A. (1973). Development temperatures in corn. Florida Soil and Crop Science Society 32, 5962.
Duncan, W. G. & Hesketh, J. D. (1968). Net photosynthetic rates, relative leaf growth rates, and leaf numbers of 22 races of maize grown at eight temperatures. Crop Science 8, 670674.
Eberhart, S. A., Penny, L. H. & Harrison, M. N. (1973). Genotype by environment interactions in maize in Eastern Africa. East African Agricultural and Forestry Journal 39, 6171.
Gallagher, J. N., Biscoe, P. V. & Scott, R. K. (1975). Barley and its environment. V. Stability of grain weight. Journal of Applied Ecology 12, 319336.
Gilmore, E. C. Jr, & Rogers, J. S. (1958). Heat units for measuring maturity in corn. Agronomy Journal 50, 611615.
Griffiths, J. F. (1969). Climate. In East Africa: Its People and Resources (ed. Morgan, W. T. W.). Nairobi: Oxford University Press.
Law, R. & Cooper, P. J. M. (1976). The effect and importance of soil temperature in determining the early growth rate and final grain yield of maize in Western Kenya. East African Agricultural and Forestry Journal 41, 189200.
Palmer, A. F. E. (1969). Translocation patterns of 14C-labelled photosynthate in the corn plant during the ear filling stage. Ph.D. thesis, Cornell University.
Shelldrake, R. Jr, (1952). Determination of the critical temperatures of snap beans, beets and sweet corn. Ph.D. thesis, Cornell University.
Walker, J. M. (1969). One degree increments in soil temperature affect maize seedling behaviour. Proceedings of the Soil Science Society of America 33, 729736.
Watts, W. B. (1973). Soil temperature and leaf expansion in Zea mays. Experimental Agriculture 9, 18.

The association between altitude, environmental variables, maize growth and yields in Kenya

  • P. J. M. Cooper (a1)

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