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Changes in growth rate and morphology of perennial ryegrass swards at high and low nitrogen levels

Published online by Cambridge University Press:  27 March 2009

Alison Davies
Affiliation:
Welsh Plant Breeding Station, Aberystwyth

Summary

The nitrogen requirements for maximum production of perennial ryegrass swards in August/September were shown to be of the order of 4 kg N/ha/day. Further increases above this level had no appreciable effect on dry-matter production, leaf area or light intercepted, but maximum tiller numbers were considerably enhanced. Shortage of nitrogenous fertilizer had comparatively little effect on crop growth rate in the early stages of regrowth, but thereafter caused the rate to fall increasingly short of potential. At high fertilizer levels crop growth rate based on total above-ground parts was linearly related to percentage light intercepted in the first month after defoliation, but values subsequently became erratic and at times negative. This change in crop growth rate and the resulting halt in effective net dry-matter production could be associated with the overall pattern of leaf and tiller formation and death, maximum net yield being achieved at the point in time when three new leaves had been produced on each tiller since cutting. It is concluded that in August and September worth-while increases in harvestable net dry matter are unlikely to occur after this stage has been reached, and that managements based on the maintenance of a complete crop cover are not likely to be successful at this time of year.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1971

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References

Alberda, Th. (1960). The effect of nitrate nutrition on carbohydrate content in Lolium perenne. Proc. VIIIth int. Grassld Congr. pp. 612–17.Google Scholar
Alberda, T. & Sibma, L. (1962). Dry matter production and light interception of crop surfaces. II. Relation between rate of growth and length of grass. Jaarb. Inst. biol. scheik. Onderz. LandbGewass. 1962, pp. 4758.Google Scholar
Alberda, T. & Sibma, L. (1968). Dry matter production and light interception of crop surfaces. 3. Actual herbage production in different years as compared with potential values. J. Br. Orassld Soc. 23, 206–15.CrossRefGoogle Scholar
Anslow, R. C. & Back, H. L. (1967). Grass growth in mid-summer and light interception and growth rate of a perennial ryegrass sward. J, Br. Orassld Soc. 22, 108–11.CrossRefGoogle Scholar
Brougham, R. W. (1956). Effect of intensity of defoliation on regrowth of pasture. Aust. J. agric. Res. 7, 377–87.CrossRefGoogle Scholar
Brougham, R. W. (1958). Leaf development in swards of white clover (Trifolium repens L.). N.Z. Jl agric. Res. 1, 707–18.CrossRefGoogle Scholar
Brougham, R. W. (1959). The effects of season and weather on the growth rate of a ryegrass and clover pasture. N.Z. Jl agric. Res. 2, 286–96.CrossRefGoogle Scholar
Brougham, R. W. & Glenday, A. C. (1967). Grass growth in mid-summer: a re-interpretation of published data. J. Br. Orassld Soc. 22, 100–7.CrossRefGoogle Scholar
Brown, R. H. & Blaser, R. E. (1968). Leaf area index in pasture growth. Herb. Abstr. 38, 19.Google Scholar
Burg, P. F. J. van (1966). Nitrate as an indicator of the nitrogen-nutrition status of grass. Proc. Xth int. Orassld Congr. pp. 267–72.Google Scholar
Cooper, J. P. & Tainton, N. M. (1968). Light and temperature requirements for the growth of tropical and temperate grasses. Herb. Abstr. 38, 167–76.Google Scholar
Cooper, J. P. (1967). Efficiency of primary canopies. Rep. Welsh Pl. Breed. Stn for 1966, pp. 1415.Google Scholar
Davidson, J. L. & Donald, C. M. (1958). The growth ofc swards of subterranean clover with particular reference to leaf area. Aust. J. agric. Res. 9, 5372.CrossRefGoogle Scholar
Davies, A. G. (1960). Conditions influencing primary growth and regrowth of perennial ryegrass. Rep. Welsh Pl Breed. Stn for 1959, pp. 110–16.Google Scholar
Davies, A. & Calder, D. M. (1969). Patterns of spring growth in swards and different grass varieties. J. Br. Orassld Soc. 24, 215–25.CrossRefGoogle Scholar
Davies, I. (1963). Life-span of individual leaves of perennial ryegrass. Sep. Welsh Pl. Breed. Stn for 1962, pp. 27–9.Google Scholar
Davies, I. (1969). The influence of management on tiller development and herbage growth. Welsh Pl. Breed. Stn tech. Bull. no. 3, pp. 121.Google Scholar
Donald, C. M. (1961). Competition for light in crops and pastures. Symp. Soc. exp. Biol. 15, 283313.Google Scholar
Donald, C. M. & Black, J. N. (1958). The significance of leaf area in pasture growth. Herb. Abstr. 28, 16.Google Scholar
Humphreys, L. R. & Robinson, A. R. (1966). Subtropical grass growth. 1. Relationship between carbohydrate accumulation and leaf area in growth. Qd J. agric. anim. Sci. 23, 211–59.Google Scholar
Hunt, L. A. (1965). Some implications of death and decay in pasture production. J. Br. Orassld Soc. 20, 2731.CrossRefGoogle Scholar
Hunt, L. A. & Brougham, R. W. (1966). Some aspects of growth in an undefoliated stand of Italian ryegrass. J. appl. Ecol. 3, 2128.CrossRefGoogle Scholar
Hunt, L. A. & Brougham, R. W. (1967). Some changes in the structure of a perennial ryegrass sward frequently but leniently defoliated during the summer. N.Z. Jl agric. Res. 10, 397404.CrossRefGoogle Scholar
Hunt, W. F. (1970). The influence of leaf death on the rate of accumulation of green herbage during pasture regrowth. J. appl. Ecol. 7, 4150.CrossRefGoogle Scholar
Jewiss, O. R. (1966). Morphological and physiological aspects of growth of grasses during the vegetative phase. Proc. 12th Easter Sch. agric. Sci. Univ. Nott. pp. 3954.Google Scholar
King, R. W. & Evans, L. T. (1967). Photosynthesis in artificial communities of wheat, lucerne and subterranean clover. Aust. J. biol. Sci. 20, 623–35.CrossRefGoogle Scholar
Loomis, R. S., Williams, W. A., Duncan, W. G., Dovrat, A. & F. Nunez, A. (1968). Quantitative descriptions of foliage display and light absorption in field communities of corn plants. Crop. Sci. 8, 352–6.CrossRefGoogle Scholar
Ludwio, L. J., Saeki, T. & Evans, L. T. (1965). Photosynthesis in artificial communities of cotton plants in relation to leaf area. 1. Experiments with progressive defoliation of mature plants. Aust. J. biol. Sci. 18, 1103–18.CrossRefGoogle Scholar
McCree, K. J. & Trottghton, J. H. (1966 a). Prediction of growth rate at different light levels from measured photosynthesis and respiration rates. Pl. Physiol., Lancaster 41, 559–66.CrossRefGoogle ScholarPubMed
McCree, K. J. & Trotjghton, J. H. (1966 b). Non-existence of an optimum leaf area index for the production rate of white clover grown under constant conditions. Pl. Physiol., Lancaster 41, 1615–22.CrossRefGoogle ScholarPubMed
Mitchell, K. J. & Coles, S. T. J. (1955). Effects of defoliation and shading on short-rotation ryegrass. N.Z. Jl Sci. Technol. A 36, 586604.Google Scholar
Piper, C. S. (1950). Soil and Plant Analysis. University of Adelaide, Adelaide.Google Scholar
Rhodes, I. (1968). Efficiency of primary canopies. Rep. Welsh Pl. Breed. Stn for 1967, p. 12.Google Scholar
Shibles, R. M. & Webeb, C. R. (1965). Leaf area, solar radiation interception and dry matter production by soybeans. Crop Sci. 5, 575–7.CrossRefGoogle Scholar
Williams, W. A., Looms, R. S. & Lepley, C. R. (1965). Vegetative growth of corn as affected by population density. 1. Productivity in relation to interception of solar radiation. Crop Sci. 5, 211–15.CrossRefGoogle Scholar
Wit, C. T. de (1965). Photosynthesis of leaf canopies. Agric. Res. Reps, Wageningen 663, 157.Google Scholar
Wit, C. T. de, Dijkshoorn, W. & Noggle, J. C. (1963). Ionic balance and growth of plants. Versl. landbouwk. Onderz. Ned. 69·15, 168.Google Scholar