Plant and Soil

, Volume 197, Issue 1, pp 79–86 | Cite as

Rooting patterns in near-isogenic lines of spring wheat for dwarfism

  • D.J. Miralles
  • G.A. Slafer
  • V. Lynch
Article

Abstract

The effects of Rht alleles on root growth and distribution in isogenic lines of spring wheat (Triticum aestivum L.) are described under different environmental conditions. Above-ground biomass, root length, root dry-weight and their distribution along the soil profile were measured by destructive sampling for growth of aerial biomass and extraction of soil cores containing roots. Field experiments were conducted under non-limiting water and nutritional conditions during two consecutive years, using an early and a late sowing date each year.

Dwarfing genes significantly reduced plant height and above-ground biomass at anthesis. In addition, stem mass ratio also was reduced with increases in the allelic dosage. Conversely, total root length and root dry-weight per unit area at anthesis were increased with decreased plant height, therefore, root mass ratio tended to be negatively correlated with plant height. Differences in distribution of root length and root dry-weight through the soil profile among lines were largely confined to the upper soil layers (i.e. the top 30 cm).

Differences in root dry-weight were more important than in root length, so that the dwarf line had the highest root mass per unit root length. Furthermore, a significant positive correlation between the root mass ratio and stem mass per unit stem length was found. It is suggested that increases in root mass per unit root length associated with Rht alleles are evidencing a surplus of photoassimilates during stem elongation which are used for thickening the roots due to the lack of alternative sinks. Agronomic implications of this effect are discussed.

dwarfing genes root and stem mass ratios root dry-weight root length wheat 

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References

  1. Blum A and Sullivan C Y 1997 The effect of plant size on wheat response to agents of drought stress. I. Root drying. Aust. J. Plant Physiol. 24, 35–41.Google Scholar
  2. Bush M G and Evans L T 1988 Growth and development in tall and dwarf isogenic lines of spring wheat. Field Crops Res. 18, 243–370.Google Scholar
  3. Calderini D F, Miralles D J and Sadras V O 1996 Appearance and growth of individual leaves as affected by semidwarfism in isogenic lines of wheat. Ann. Bot. 77, 583–589.Google Scholar
  4. Gale M D and Youssefian S 1985 Dwarfing genes of wheat. In Progress in Plant Breeding. Ed. G E Russell. pp 1–35. Butterworth and Co., London.Google Scholar
  5. Gardner J S, Hess W M and Trione E J 1985 Development of young wheat spike: a SEM study of Chinese Spring wheat. Am. J. Botany 72, 548–559.Google Scholar
  6. Holbrook F S and Welsh J R 1980 Soil-water use by semidwarf and tall winter wheat cultivars under dryland field conditions. Crop Sci. 20, 244–246.Google Scholar
  7. Laing D R and Fischer R A 1977 Adaptation of semidwarf wheat cultivars to rainfed conditions. Euphytica 26, 129–139.Google Scholar
  8. McCaig T N and Morgan J A 1993 Root and shoot dry matter partitioning in near-isogenic wheat lines differing in height. Can. J. Plant Sci. 73, 679–689.Google Scholar
  9. Miralles D J and Slafer G A 1995 Yield, biomass and yield components in dwarf, semidwarf and tall isogenic lines of spring wheat under recommended and late sowing dates. Plant Breeding 14, 392–396.Google Scholar
  10. Pepe J F and Welsh J R 1979 Soil water depletion patterns under dryland field conditions of closely related height lines of winter wheat. Crop Sci. 19, 677–680.Google Scholar
  11. Richards R A 1992 The effects of dwarfing genes in spring wheat in dry environments. II. Growth, water use and water-use efficiency. Aust. J. Agric. Res. 43, 529–539.Google Scholar
  12. Siddique K H M, Belford R K and Tennant D 1990 Root:shoot ratios of old andmodern, tall and semidwarfwheats in a mediterranean environment. Plant Soil 121, 89–98.Google Scholar
  13. Slafer G A and Andrade F H 1989 Genetic improvement in bread wheat (Triticum aestivum L.) yield in Argentina. Field Crops Res. 21, 289–296.Google Scholar
  14. Slafer G A, Satorre E H and Andrade F H, 1994 Increases in grain yield in bread wheat from breeding and associated physiological changes. In Genetic Improvement of FieldCrops. Ed.G A Slafer. pp 1–68. Marcel Dekker Inc., New York.Google Scholar
  15. Slafer G A and Rawson H M 1994 Sensitivity of wheat phasic development to major environmental factors: a re-examination of some assumptions made by physiologists and modellers. Aust. J. Plant Physiol. 21, 193–426.Google Scholar
  16. Srivastava J P 1987 Barley and wheat improvement for moisture-limiting areas inWest Asia and North Africa. In Drought Tolerance inWinter Cereals. Eds. Srivastava J P, Porceddu E, Acevedo E and Varma S. pp 65–79. John Wiley & Sons Ltd, New York.Google Scholar
  17. Syme J R 1970 A high yielding Mexican semi-dwarf wheat and the relationship of yield to harvest index and other varietal characteristics. Aust. J. Exp. Agric. Anim. Husb. 10, 350–353.Google Scholar
  18. Tennant D 1975 A test of a modified line-intersected method of estimating root length. J. Ecol. 63, 995–1001.Google Scholar
  19. Zadoks J C, Chang T T and Konzak C F 1974 Decimal code for the growth stage of cereals. Weed Res. 14, 415–421.Google Scholar

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • D.J. Miralles
    • 1
  • G.A. Slafer
    • 1
  • V. Lynch
    • 1
  1. 1.Catedra de Cerealicultura, Departamento de Produccion Vegetal, Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresArgentina

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