Salt tolerance and ionic relations of wheat as affected by individual chromosomes of salt-tolerant Lophopyrum elongatum

Abstract

OMIELAN, J. A., EPSTEIN, E., and DVORAK, J. 1991. Salt tolerance and ionic relations of wheat as affected by individual chromosomes of salt-tolerant Lophopyrurn elongaturn. Genome, 34: 961 -974. Bread wheat cv. Chinese Spring (CS), an amphiploid from a cross between CS and salt-tolerant Lophopyrurn ( = Agropyron) elongaturn (Host) Love, 19 of 21 possible disomic substitution lines of L. elongaturn chromosomes for CS homoeologues, and a check cultivar, PI 178704, were grown in a replicated field trial under two levels of salinity and control conditions. Under salinity, the amphiploid greatly outperformed CS in grain yield, biomass, and other characters, indicating that it is more salt tolerant than CS. Of the seven L. elongaturn chromosomes, six increased salt tolerance in disomic substitution lines; the most dramatic increase was conferred by chromosome 3E. Increased salt tolerance of the amphiploid was associated with the exclusion of Na + and C1-and inclusion of K + as well as retranslocation of K + . Lophopyrurn chromosomes controlling these physiological characters were identified. Some of the chromosomes had multiple effects, where as others affected only a specific character. The largest effects were associated with chromosome 3E. In addition, several wheat chromosomes controlled the exclusion or inclusion of these ions; the most notable effects were by chromosome 4D. Salt tolerance correlated negatively with Na+ and positively with K + concentration in the flag leaf and with the K + / N a + ratios. The relationships were strong enough to be exploited as selection tools in the breeding of salt-tolerant wheat cultivars.

Molecular and functional characterization of a novel low-affinity cation transporter (LCT1) in higher plants

“…More than one low-affinity pathway for Na ϩ and K ϩ uptake has been suggested to exist in plants. The presence of multiple loci linked to salt tolerance and Na ϩ exclusion supports the idea of multiple pathways for Na ϩ uptake (10). The emerging molecular evidence supports the classical tracer flux data (11,12), showing that higher plants have multiple K ϩ and Na ϩ uptake mechanisms in the plasma membrane for acquisition.…”

“…Nevertheless, physiological as well as genetic studies show that more than one pathway for Na ϩ uptake across the plasma membrane of plant roots exists (5,10,12). The properties of LCT1 described here indicate that LCT1 may encode one of the molecular components of low-affinity Na ϩ uptake in planta.…”

Sodium and potassium transport to the xylem are inherited independently in rice, and the mechanism of sodium: potassium selectivity differs between rice and wheat

“…Salinity tolerance in wheat has been attributed to the exclusion of sodium and compensatory accumulation of potassium in young leaves (Omielan et al 1991;Colmer et al 1995). In hexaploid wheat a K:Na discrimination trait has been located on the long arm of chromosome 4D (Gorhatn et al 1987).…”

Specific Variation in Shoot Growth and Root Traits Under Waterlogging Conditions of The Seedlings of Tribe Triticeae including Mizutakamoji (Agropyron Humidum)

“…Khan (2000) also reported the recombination of chromosomes between wheat and A. intermedium. Furthermore, chromosome addition lines of A. elongatum on the genetic background of wheat demonstrated the possibility of improving drought tolerance (Sutka et al, 1995;Farshadfar et al, 2004) and salt tolerance (Dvorak and Ross, 1986;Forster et al, 1987Forster et al, , 1988Omielan et al, 1991;Mahmood and Quarrie, 1993;Suiyun et al, 2004) in wheat. Although fertile hybrids of A. humidum with wheat and barley have not been acquired, such lines might be useful in breeding programs to transfer waterlogging tolerance into wheat and barley genetic backgrounds.…”