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The relations between the main shoot and tillers in barley plants

Published online by Cambridge University Press:  27 March 2009

E. J. M. Kirby
Affiliation:
Plant Breeding Institute, Trumpington, Cambridge CB2 2LQ
H. G. Jones
Affiliation:
Plant Breeding Institute, Trumpington, Cambridge CB2 2LQ

Summary

Barley plants normally produce some tillers which die at an early stage, without bearing an ear. To investigate the proposition that these non-ear-bearing tillers may be wasteful of plant resources, two experiments were made in which the effect of tiller growth on the growth and final size of the main shoot was assessed. In one experiment, tillers were removed at a very early stage when they were a few mm long, or later when they were just emerging from the subtending leaf sheath. In the other experiment the main shoot was removed from the embryo and the size of the coleoptile tiller which grew in its absence was measured.

Tiller removal affected the growth and final size of the main shoot. Leaves emerged more quickly on the main shoot of the detillered plants and were bigger and sometimes more in number. The main shoot of the detillered plants was heavier and it bore a greater weight of grain because the ear had more and heavier grains. In the experiments where the main shoot was removed the coleoptile tiller produced more leaves, which emerged more rapidly and it bore more grains than the coleoptile tiller of the intact plants.

It is concluded that tillers, during their initiation and early growth, compete with the main shoot for a limited supply of resources, thus reducing the size of the main shoot. As some of the resources of the plant are used to produce tillers which die at an early stage and make no contribution to the final grain yield, it appears that they should be regarded as wasteful and that their production may reduce the final grain yield. The physiology of the initiation, growth and early death of these non-ear-bearing tillers requires further investigation.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1977

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References

Clifford, P. E., Marshall, C. & Sagar, G. R. (1973). The reciprocal transfer of radiocarbon between a developing tiller and its parent shoot in vegetative plants of tiolium muUiflorum Lam. Annals of Botany 37, 777–85.CrossRefGoogle Scholar
Donald, C. M. (1968). The breeding of crop ideotypes. Euphytica 17, 385403.CrossRefGoogle Scholar
Hunter, H. (1937). Some aspects of malting barley breeding in Great Britain. Comptes Bendus Ve Congris International Technique et Chimique des Industries Agricoles 1, 291309.Google Scholar
Jones, H.G. & Kirby, E. J. M. (1977). Effects of manipulation of number of tillers and water supply on grain yield in barley. Journal of Agricultural Science, Cambridge 88, 391–7.CrossRefGoogle Scholar
Kirby, E. J. M. (1973a). The control of leaf and ear size in barley. Journal of Experimental Botany 24, 567–78.CrossRefGoogle Scholar
Kirby, E. J. M. (1973b). Effect of temperature on ear abnormalities in unieulm barley. Journal of Experimental Botany 24, 935–47.CrossRefGoogle Scholar
Kirby, E. J. M. (1977). The growth of the shoot apex and the apical dome of barley during ear initiation. Annals of Botany (in the press).CrossRefGoogle Scholar
Kirby, E. J. M. & Faris, D. G. (1972). The effect of plant density on tiller growth and morphology in barley. Journal of Agricultural Science, Cambridge 78, 281–8.CrossRefGoogle Scholar
Mitcheson, R. C. & Stowell, K. C. (1970). Application of new analytical techniques to routine malt analysis. Journal of the Institute of Brewing 76, 335–9.CrossRefGoogle Scholar
Rawson, H. M. & Donald, C. M. (1969). The absorption and distribution of nitrogen after floret initiation in wheat. Australian Journal of Agricultural Research 20, 799808.CrossRefGoogle Scholar
Rawson, H. M. & Hofstra, G. (1969). Translocation and remobilization of 14C assimilated at different stages by each leaf of the wheat plant. Australian Journal of Biological Sciences 22, 321–31.CrossRefGoogle Scholar
Rhodes, A. P. & Jenkins, G. (1975). The effect of varying nitrogen supply on the protein composition of a high lysine mutant of barley. Journal of the Science of Food and Agriculture 26, 705–9.CrossRefGoogle ScholarPubMed
Rogan, P. G. & Smith, D. L. (1974). The development of the shoot apex of Agropyron repens (L.) Beauv. Annals of Botany 38, 967–76.CrossRefGoogle Scholar
Seiler, , Kelbitsch, H., Michael, G. & Wilberg, E. (1974). Benziehungen zwischen Korngewioht und cytokinin-aktivitat bei Sommergerste, untersuoht am Beispiel des Abschneidens von Bestokungstrieben. Vereinigungfur Angewandte Botanik 48, 299307.Google Scholar
Smith, H. F. (1933). The physiological relations between tillers of a wheat plant. Journal of the Council for Scientific and Industrial Research, Australia 34, 3242.Google Scholar