INVESTIGADORES
SANTA MARIA guillermo Esteban
artículos
Título:
Potassium:sodium selectivity in wheat and the amphiploid cross
Autor/es:
SANTA MARÍA, GE; EPSTEIN E
Revista:
PLANT SCIENCE
Referencias:
Año: 2001 vol. 160 p. 523 - 534
ISSN:
0168-9452
Resumen:
Abstract The early response of K and Na net fluxes to different external NaCl and KCl levels has been studied in wheat (Triticum aesti6um L.) and the amphiploid cross wheat X Lophopyrum elongatum (Host) Lo¨ve in culture solution experiments. We found that during the first 24 h of exposure to 100 or 200 mM NaCl, at low K levels, the amphiploid absorbed, translocated and allocated to the youngest leaf less Na than the wheat parental line. During that period, the amphiploid retained more K than wheat. Short-term uptake studies with 86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na and Na net fluxes to different external NaCl and KCl levels has been studied in wheat (Triticum aesti6um L.) and the amphiploid cross wheat X Lophopyrum elongatum (Host) Lo¨ve in culture solution experiments. We found that during the first 24 h of exposure to 100 or 200 mM NaCl, at low K levels, the amphiploid absorbed, translocated and allocated to the youngest leaf less Na than the wheat parental line. During that period, the amphiploid retained more K than wheat. Short-term uptake studies with 86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na6um L.) and the amphiploid cross wheat X Lophopyrum elongatum (Host) Lo¨ve in culture solution experiments. We found that during the first 24 h of exposure to 100 or 200 mM NaCl, at low K levels, the amphiploid absorbed, translocated and allocated to the youngest leaf less Na than the wheat parental line. During that period, the amphiploid retained more K than wheat. Short-term uptake studies with 86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na levels, the amphiploid absorbed, translocated and allocated to the youngest leaf less Na than the wheat parental line. During that period, the amphiploid retained more K than wheat. Short-term uptake studies with 86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na than the wheat parental line. During that period, the amphiploid retained more K than wheat. Short-term uptake studies with 86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na86Rb and 22Na showed that K(86Rb) and Na influxes were not involved in genotypic differences in K(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na(86Rb) and Na net uptake observed after 6 h of exposure to salt stress. Differences in K(86Rb) net uptake could be attributed to differences in K(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na(86Rb) efflux and:or to K(86Rb) accumulation by root vacuoles. The possibility that differential shrinkage of protoplast volume plays a role in the genotypic difference in K retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na retention cannot be ruled out. On the other hand, Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na efflux did not contribute significantly to differences in Na net uptake between these genotypes. Hence, differences in Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na net uptake were attributed to differences in the transport of Na to the shoot. The presence in the amphiploid of fast acting mechanisms able to enhance Na:K selectivity at different plant levels minimizes the early build-up of Na:K selectivity at different plant levels minimizes the early build-up of Na concentration, and K substitution by Na, in the growing tissue of the leaf. © 2001 Elsevier Science Ireland Ltd. All rights reserved. substitution by Na, in the growing tissue of the leaf. © 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Wheat (Triticum aesti6um L.); Lophopyrum elongatum; Potassium; Salinity; Selectivity; Sodium; Uptake. www.elsevier.com:locate:plantsci: Wheat (Triticum aesti6um L.); Lophopyrum elongatum; Potassium; Salinity; Selectivity; Sodium; Uptake. www.elsevier.com:locate:plantsci:locate:plantsci