Photosynthetica

, Volume 35, Issue 3, pp 381–390

Relationships among Rhizosphere Oxygen Deficiency, Root Restriction, Photosynthesis, and Growth in Baldcypress (Taxodium Distichum L.) Seedlings

  • S.R. Pezeshki
  • M.I. Santos
Article

Abstract

Seedlings of baldcypress (Taxodium distichum L.) grown in sealed containers containing nutrient solution were subjected to root-zone oxygen deficiency, physical restriction, and the combined stresses in a greenhouse. After six weeks of treatments (Phase I), half of the plants were harvested. The remaining half were allowed to continue (Phase II) under various treatments except plants that had restricted roots were freed thus allowing free expansion of roots into the nutrient solution. Oxygen deficiency and root physical restriction inhibited plant gas exchange parameters. Net photosynthetic rate (PN) was significantly higher in aerated unrestricted root (AUR) plants than in aerated root restricted (AR) plants and in anaerobic root unrestricted (FUR) plants than in anaerobic root restricted (FR) plants. After Phase I, FUR plants' shoot and root biomasses were 57.0 and 30.6 % lower than those of AUR plants, and AUR plants showed 3.3 and 3.8 times greater shoot and root biomasses than the AR plants, respectively. During Phase II, PN recovered rapidly in plants under aerated conditions, but not in plants under anaerobic conditions. The removal of physical root restriction under both aerated and anaerobic conditions resulted in rapid shoot and root growth in seedlings. Hence, root restriction or root-zone anaerobiosis, reductions in plant gas exchange, and biomass production in baldcypress were closely interrelated. In addition, root release from restriction was related to the regain of photosynthetic activity and biomass growth. The results support the previously proposed source-sink feed-back inhibition of photosynthesis in plants subjected to root-zone oxygen deficiency or physical restriction.

anaerobiosis biomass relative growth rate root shoot ratio shoot 

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References

  1. Atwell, B.J.: The effect of soil compaction on wheat during early tillering, 1, Growth development and root structure.-New Phytol. 115: 29–35, 1990.Google Scholar
  2. Barta, A.L.: Supply and partitioning of assimilates to roots of Medicago sativa L. and Lotus corniculatus L. under anoxia.-Plant Cell Environ. 10: 151–156, 1987.Google Scholar
  3. Barta, A.L.: Response of alfalfa and birdsfoot trefoil to shoot removal and root anoxia.-Crop Sci. 28: 275–278, 1988a.Google Scholar
  4. Barta, A.L.: Response of field-grown alfalfa to root waterlogging and shoot removal. I. Plant injury and carbohydrate and mineral content of roots.-Agron. J. 80: 889–892, 1988b.Google Scholar
  5. Bengough, A.G., Mullins, C.E.: Restriction to root growth limit the yield of shoots of irrigated white clover.-Aust. J. agr. Res. 44: 121–135, 1990.Google Scholar
  6. Boone, F.R., Veen, B.W.: The influence of mechanical resistance and phosphate supply on morphology and function of maize roots.-Neth. J. agr. Sci. 30: 179–192, 1982.Google Scholar
  7. Carmi, A., Heuer, B.: The role of roots in control of bean shoot growth.-Ann. Bot. 48: 519–527, 1981.Google Scholar
  8. Carmi, A., Hesketh, J.D., Enos, W.T., Peters, D.B.: Interrelationships between shoot growth and photosynthesis as affected by root growth restriction.-Photosynthetica 17: 240–245, 1983.Google Scholar
  9. Cook, A., Marriott, C.A., Seel, W., Mullins, C.E.: Effects of soil mechanical impedance on root and shoot growth of Lolium perenne, Agrostis capillaris, and Trifolium repens.-J. exp. Bot. 47: 1075–1084, 1996.Google Scholar
  10. Kozlowski, T.T.: Plant response to flooding of soil.-BioScience 34: 162–167, 1984.Google Scholar
  11. Kramer, P.J.: Water Relations in Plants.-Academic Press, New York 1983.Google Scholar
  12. Krizek, D.T., Carmi, A., Mirecki, R.M., Snyder, F.W., Bunce, J.A.: Comparative effects of soil moksture stress and restricted root zone volume on morphogenetic and physiological responses of soybean (Glycine max (L.) Merr.).-J. exp. Bot. 36: 25–38, 1985.Google Scholar
  13. Ledig, F.T., Bormann, F.H., Wenger, K.F.: The distribution of dry matter growth between shoot and roots in loblolly pine.-Rot. Gaz. 131: 349–359, 1970Google Scholar
  14. Levitt, J.: Responses of Plants to Environmental Stresses.-Academic Press, New York-London 1972.Google Scholar
  15. Neales, T.F., Incoll, L.D.: The control of leaf photosynthesis rate by the level of assimilate concentration in the leaf: A review of the hypothesis.-Bot. Rev. 34: 107–125, 1968.Google Scholar
  16. NeSmith, D.S.: Influence of root restriction on two cultivars of summer squash (Cucurbita pepo L.).-J. Plant Nutr. 16: 421–431, 1993.Google Scholar
  17. Oussible, M., Crookston, R.K., Larson, W.E.: Subsurface compaction reduces the root and shoot growth and grain yield of wheat.-Agron. J. 84: 519–527, 1992.Google Scholar
  18. Peterson, C.M., Klepper, B., Pumphrey, F.V., Rickman, R.W.: Restricted rooting decreases tillering and growth of winter wheat.-Agron. J. 76: 861–863, 1984.Google Scholar
  19. Pezeshki, S.R.: Root responses of flood-tolerant and flood-sensitive tree species to soil redox conditions.-Trees 5: 180–186, 1991.Google Scholar
  20. Pezeshki, S.R.: Differences in patterns of photosynthetic responses to hypoxia in flood-tolerant and flood-sensitive tree species.-Photosynthetica 28: 423–430, 1993.Google Scholar
  21. Pezeshki, S.R.: Plant response to flooding.-In: Wilkinson, R.E. (ed.): Plant-Environment Interactions. Pp. 280–321. Marcel Dekker, New York-Basel-Hong Kong 1994.Google Scholar
  22. Radford, P.J.: Growth analysis formulae-their use and abuse.-Crop Sci. 7: 171–175, 1967.Google Scholar
  23. Robbins, N.S., Pharr, D.M.: Effect of restricted root growth on carbohydrate metabolism and whole-plant growth of Cucumis sativus L.-Plant Physiol. 87: 409–413, 1988.Google Scholar
  24. Ruff, M.S., Krizek, D.T., Mirecki, R.M., Inouye, D.W.: Restricted root zone volume: Influence on growth and development of tomato.-J. amer. Soc. hort. Sci. 112: 763–769, 1987.Google Scholar
  25. Stitt, M., Schulze, D.: Does Rubisco control the rate of photosynthesis and plant growth? An exercise in molecular ecophysiology.-Plant Cell Environ. 17: 465–487, 1994.Google Scholar

Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • S.R. Pezeshki
    • 1
  • M.I. Santos
    • 2
  1. 1.Department of BiologyUniversity of MemphisMemphisUSA
  2. 2.Florida Department of AgricultureDivision of Plant IndustryHomesteadUSA

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