Hostname: page-component-848d4c4894-2xdlg Total loading time: 0 Render date: 2024-07-03T10:33:33.623Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of applied nitrogen on grass leaf initiation, development and death in field swards

Published online by Cambridge University Press:  27 March 2009

P. Joy Pearse  and
D. Wilman
P. Joy Pearse
Affiliation:
Department of Agriculture, University College of Wales, Aberystwyth
D. Wilman
Affiliation:
Department of Agriculture, University College of Wales, Aberystwyth
Get access Rights & Permissions [Opens in a new window]

Summary

Effects of three levels of N application and four intervals between harvests on field swards of perennial ryegrass (Lolium perenne L.) were studied during 6-week periods in summer and spring. Ryegrass was compared with tall fescue (Festuca arundinacea Schreb.) in spring and autumn.

The application of N increased the rate of production of leaf primordia, the number of leaf primordia per tiller, the length of the shoot apex, the rate of development of primordia into unemerged leaves, the number of leaves emerging, the number of live, emerged leaves per tiller, the leaf extension rate and weight of blade emerging and the net gain, per tiller per day, in blade length and weight. The application of N tended to reduce the number of unemerged leaves per tiller and the length of apex per primordium. Applied N retarded leaf death (whether measured as numbers, length or weight) during the first 2–3 weeks after application and accelerated death subsequently. During the 1st week of the summer periods, the net gain in green blade length and weight per tiller was doubled by 22 kg N/ha and trebled by 66 kg N (compared with nil). During the final fortnight of the summer periods, the net gain in green blade length and weight was less with the 6-than with the 3- or 2-week interval, and, in the case of the 6-week interval, the positive effect of applied N on the rate of development of primordia into unemerged leaves and on the number of leaves emerging had been lost.

The ryegrass had more leaf primordia and unemerged leaves per tiller than the fescue, and a faster rate of development of primordia into unemerged leaves and of unemerged into emerged leaves.

A ryegrass leaf spent a broadly similar length of time in each of the three stages, primordium, unemerged leaf and fully expanded live leaf, and about half as long as one of those stages as an emerging leaf. At nil N a leaf developed to about 6000 times its starting length (as a newly-formed primordium) in 67 days in summer; at high N a leaf developed to about 10500 times its starting length in 53 days. The percentage increase in length per day was greatest during the unemerged leaf stage.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 103 , Issue 2 , October 1984 , pp. 405 - 413
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

Davies, A. (1971). Changes in growth rate and morphology of perennial ryegrass swards at high and low nitrogen levels. Journal of Agricultural Science, Cambridge 77, 123–134.CrossRefGoogle Scholar
Pearse, P. J. (1983). Detailed studies of grass growth in field swards, with particular reference to response to nitrogen application and frequency of defoliation. Ph.D. thesis, University College of Wales, Aberystwyth.Google Scholar
Robson, M. J. & Deacon, M. J. (1978). Nitrogen deficiency in small closed communities of S24 ryegrass. II. Changes in the weight and chemical composition of single leaves during their growth and death. Annals of Botany 42, 1199–1213.CrossRefGoogle Scholar
Ryle, G. J. A. (1964). A comparison of leaf and tiller growth in seven perennial grasses as influenced by nitrogen and temperature. Journal of the British Grassland Society 19, 281–290.CrossRefGoogle Scholar
Wilman, D. (1980). Early spring and late autumn response to applied nitrogen in four grasses. 1. Yield, number of tillers and chemical composition. Journal of Agricultural Science, Cambridge 94, 425–442.CrossRefGoogle Scholar
Wilman, D., Koocheki, A. & Lwoga, A. B. (1976). The effect of interval between harvests and nitrogen application on the proportion and yield of crop fractions and on the digestibility and digestible yield and nitrogen content and yield of two perennial ryegrass varieties in the second harvest year. Journal of Agricultural Science, Cambridge 87, 59–74.CrossRefGoogle Scholar
Wilman, D. & Mares Martins, V. M. (1977). Senescence and death of herbage during periods of regrowth in ryegrass and red and white clover, and the effect of applied nitrogen. Journal of Applied Ecology 14, 615–620.CrossRefGoogle Scholar
Wilman, D. & Mohamed, A. A. (1980). Early spring and late autumn response to applied nitrogen in four grasses. 2. Leaf development. Journal of Agricultural Science, Cambridge 94, 443–453.CrossRefGoogle Scholar
Wilman, D. & Mohamed, A. A. (1981). Response to nitrogen application and interval between harvests in five grasses. 2. Leaf development. Fertilizer Research 2, 3–20.CrossRefGoogle Scholar
Wilman, D. & Pearse, P. J. (1984). Effects of applied nitrogen on grass yield, nitrogen content, tillers and leaves in field swards. Journal of Agricultural Science, Cambridge 103, 201–211.CrossRefGoogle Scholar
Wilman, D. & Wright, P. T. (1983 a). Some effects of applied introgen on the growth and chemical composition of temperate grasses. Herbage Abstracts 53, 387–393.Google Scholar
Wilman, D. & Wright, P. T. (1983 b). Some effects of applied nitrogen on grass growth in field swards at different times of year. Proceedings of the XIVth International Grassland Congress, Lexington, Kentucky, U.S.A., pp. 297–299.Google Scholar
Woolhouse, H. W. (1972). Ageing Processes in Higher Plants. Oxford Biology Readers no. 30 (ed.Head, J. J. and Lowenstein, O. E.). Oxford: University Press.Google Scholar