The Influence of the Rhizosphere on Crop Productivity

  • J. M. Whipps
  • J. M. Lynch
Part of the Advances in Microbial Ecology book series (AMIE, volume 9)

Abstract

The rhizosphere region is a variable zone containing a proliferation of microorganisms inside and outside the plant root. Many compounds are both taken up and passed out. Under normal growth conditions the rhizosphere exists because of the continuous loss of many forms of plant metabolites, which are rapidly utilized by microorganisms. Consequently, these rhizosphere microorganisms are in a position to affect both subsequent loss of material from the roots and nutrient uptake by the roots. In natural ecosystems an equilibrium develops between the plant and microorganisms that is affected only by the normal growth of plant and seasonal changes in the environment. However, in agriculture, man continually changes the normal equilibrium by manifold means. (e.g., plant monoculture, herbicide, fungicide and pesticide treatments, fertilizer application, and cultivation), all of which modify subsequent plant growth and the associated rhizosphere biota. Because of the importance of agriculture, the majority of work on the rhizosphere and its effects on plant growth has involved research on crop plants and, although this has provided great insight into rhizosphere—plant interactions in these relatively few species, some care should be taken in extrapolating such results to all natural ecosystems. With this proviso, we attempt to show, first, the effect the plant has on development and maintenance of the rhizosphere and, second, the influence the rhizosphere has on plant physiology and consequently crop productivity, highlighting areas of research likely to be rewarding both scientifically and commercially in the future. We do not attempt a complete review of the literature, since there have been reviews on many aspects of rhizosphere biology in recent years (Barber, 1978; Hale, et al. 1978; Newman, 1978; Balandreau and Knowles, 1978; Hale and Moore, 1979; Bowen, 1979, 1980, 1982; Woldendorp, 1981; Foster and Bowen, 1982; Lynch, 1982, 1983; Subba Rao, 1982a; Suslow, 1982), but rather choose specific examples to illustrate our major points.

Keywords

Biological Control Nitrogen Fixation Mycorrhizal Root Carbon Loss Trichoderma Harzianum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1986

Authors and Affiliations

  • J. M. Whipps
    • 1
  • J. M. Lynch
    • 2
  1. 1.Agricultural Research Council, Letcome LaboratoryWantage, OxonEngland
  2. 2.Plant Pathology and Microbiology DepartmentGlasshouse Crops Research InstituteLittlehampton, West SussexEngland

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