793
Views
135
CrossRef citations to date
0
Altmetric
Original Articles

CONTRIBUTION OF PROLINE AND INORGANIC SOLUTES TO OSMOTIC ADJUSTMENT IN COTTON UNDER SALT STRESS

, , &
Pages 599-612 | Published online: 14 Feb 2007
 

Abstract

Physiological responses to salt stress were investigated in two cotton (Gossypium hirsutum L.) cultivars (Pora and Guazuncho) grown hydroponically under various concentrations of NaCl. Dry matter partitioning, plant water relations, mineral composition and proline content were studied. Proline and inorganic solutes were measured to determine their relative contribution to osmotic adjustment. Both leaf water potential (Ψw) and osmotic potential (Ψs)decreased in response to NaCl levels. Although Ψwand Ψs decreased during salt stress, pressure potential Ψp remained between 0.5 to 0.7 MPa in control and all NaCl treatments, even under 200 mol m−3 NaCl. Increased NaCl levels resulted in a significant decrease in root, shoot and leaf growth biomass. Root / shoot ratio increased in response to salt stress. The responses of both cultivars to NaCl stress were similar. Increasing salinity levels increased plant Na+ and Cl. Potassium level remained stable in the leaves and decreased in the roots with increasing salinity. Salinity decreased Ca2+ and Mg2+ concentrations in leaves but did not affect the root levels of these nutrients. The K/Na selectivity ratio was much greater in the saline treated plants than in the control plants. Osmotic adjustment of roots and leaves was predominantly due to Na+ and Cl accumulation; the contribution of proline to the osmotic adjustment seemed to be less important in these cotton cultivars.

ACKNOWLEDGMENTS

This work is part of a M.S. Thesis by D.A.M., Federal University of Viçosa, Brazil 1998. D.A.M. was supported by a scholarship from CICyT-U.N.S.E., Argentina, and partially by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brasil). The authors gratefully acknowledge the contributions of Dr. Moacyr Maestri for critical reading of the manuscript.

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 61.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 495.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.