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The relationship between productivity and some components of canopy structure in ryegrass (Lolium spp.)

II. Yield, canopy structure and light interception

Published online by Cambridge University Press:  27 March 2009

Ian Rhodes
Affiliation:
Welsh Plant Breeding Station, Aberystwyth

Summary

Productivity and percentage conversion of light energy were measured in (a)clonallypropagated swards of populations of genotypes selected from the variety S. 321 forcontrasting combinations of leaf rigidity and tiller angle, and (b) families from assortativecrosses between genotypes of this variety of differing canopy structure. A further experiment was carried out to examine the canopy structure and pattern of light interception of populations, families and genotypes of contrasting productivity.

Under infrequent cutting (28–34 days) the tiller population selected for erect tillers and rigid leaves was more productive than those selected for prostrate tillers and rigid leaves, and prostrate tillers and lax leaves. Under frequent cutting (14–17 days), however, the populations with prostrate tillers were most productive.

Considerable differences existed in the productivity of the S. 321 families, and their relative performance differed under the two cutting frequencies. Under infrequent cutting the highest yielding family was 17% more productive than the base population, whilst under frequent cutting the yield of the most productive family was 19% greater than that of the base population.

The heritability of sward yield was 0·64 under infrequent cutting and 0·86 under frequent cutting.

The most productive genotypes, populations and families under infrequent cutting had the highest leaf-area index (LAI) at complete light interception and the lowest extinction coefficients for visible radiation (Kvis). By contrast, under frequent cutting the most productive types had high extinction coefficients and large LAI in the basal layers of the canopy.

The physiological basis of differences in productivity is discussed in relation to canopy characters whioh may be used as selection criteria for increasing the efficiency of light utilization in herbage grasses.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1971

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References

Brown, R. H. & Blaser, R. E. (1968). Leaf area index in pasture growth. Herb. Abstr. 38, 1—9.Google Scholar
Büring, J. (1970). The role of leaves in the after-cut grass growing. Sel'-khoz Biologiya 5, 470–2 (seen in Herb. Abstr. item 2828, vol. 40, p. 429 (1970)).Google Scholar
Cooper, J. P. (1969). Potential forage production. Occ Symp. No. 5 Br. Grassld Soc. 513.Google Scholar
Cooper, J. P. & MacColl, D. (1966). Energy conversion in the grass plant. Rep. Welsh Pl. Breed. Stn for 1965, pp. 1213.Google Scholar
Donald, C. M. (1963). Competition among crop and pasture plants. Adv. Agron. 15, 1118.CrossRefGoogle Scholar
Falconer, D. S. (1960). Introduction to Quantitative Genetics. Edinburgh: Oliver and Boyd.Google Scholar
Hunt, L. A. (1966). Ash and energy content of material from seven forage grasses. Crop Sci. 6, 507–9.Google Scholar
Jenkin, T. J. (1931). Methods and techniques of selection, breeding and strain building in grasses. Bull. Bur. Pl. Genet. Aberystwyth. 3, 534.Google Scholar
Jewiss, O. R. & Woledge, J. (1967). The effect of age on rate of apparent photosynthesis in leaves of tall fescue. (Festuca arundinacea Schreb). Ann. Bot. N.S. 31, 661–71.CrossRefGoogle Scholar
Ludlow, M. M. (1970). Leaf angle and plant growth. J. Aust Inst. Agric. Sci. 35, 153–4.Google Scholar
Raymond, W. F. (1969). Improving the nutritive value of herbage grasses. Occ. Symp No. 5, Br. Grassld Soc., pp. 2936.Google Scholar
Rhodes, I. (1968 a). Efficiency of primary canopies. Rep. Welsh Pl. Breed. Stn for 1967, p. 12.Google Scholar
Rhodes, I. (1968 b). Yield of contrasting ryegrass varieties in monoculture and mixed culture. J. Br. Grassld. Soc. 23, 156–8.CrossRefGoogle Scholar
Rhodes, I. (1969 a). The relationship between productivity and some components of canopy structure in ryegrass (Lolium spp.) 1. Leaf length. J. agric. Sci., Camb. 73, 315–19.CrossRefGoogle Scholar
Rhodes, I. (1969 b). Yield, canopy structure and light interception of two ryegrass varieties in mixed culture and monoculture. J. Br. Grassld. Soc. 24, 123–7.Google Scholar
Rhodes, I. (1971). Productivity and canopy structure of two contrasting varieties of perennial ryegrass (Lolium perenne L.) grown in a controlled environment. J. Br. Grassld. Soc. 26, 915.CrossRefGoogle Scholar
Rogers, H. H. (1967). Breeding for maximum production Occ. Symp No 3 Br. Grassld. Soc, pp. 6673.Google Scholar
Sant, F. I. & Rhodes, I. (1970). A note on the relationship between leaf rigidity and leaf anatomy in Lolium perenne L. J. Br. Grassld. Soc. 25, 233–5.CrossRefGoogle Scholar
Szeicz, G., Monteith, J. L. & Dos, Santos J. M. (1964). Tube solarimeter to measure radiation among plants. J. appl. Ecol. 1, 169–74.CrossRefGoogle Scholar
Treharne, K. J., Cooper, J. P. & Taylor, T. H. (1968). Growth response of orchard grass (Dactylis glomerata L.) to different light and temperature environments II. Leaf age and photosynthetic activity. Crop Sci. 8, 441–5.Google Scholar
Vanstone, F. H. (1968). The development of a system of instrumentation for recording crop environments. Rep. Welsh Pl. Breed. Stn for 1967, pp. 135–60.Google Scholar
Wonkyi-Appiah, J. B. (1970). Selection for leaf growth in ryegrass and its influence on potential production. Ph.D. thesis, University of Wales (unpublished).Google Scholar
Yoshida, S., Navasero, S. A. & Ramirez, E. A. (1969). Effects of silica and nitrogen supply on some leaf characters of the rice plant. Pl. Soil. 31, 4856.Google Scholar