An assessment of the salt tolerance of wheat/Thinopyrum bessarabicum 5E^b addition and substitution lines

Abstract

Lines of Triticum aestivum cv. Chinese Spring carrying an additional chromosome 5E'' from Thinopyrum bessarabicum or having chromosome 5A or 5D replaced by chromosome 5E^ were screened in hydroculture for tolerance to salt. The previously reported tolerance of the 5E'' addition line was confirmed and the two substitution lines were shown to have a higher level of survival in 175 mol/m^ NaCI than both the addition and the 'Chinese Spring' parent. Reasons for the better tolerance of the substitutions are discussed.

Introgression of salt‐tolerance genes from Thinopyrum bessarabicum into wheat

“…a 25% higher frequency of survival for CS5E^(5D) and a 29-2% higher frequency of survival for CS5E^(5A), they also showed a significantly higher frequency of survival than the CS5E^ addition line itself (14-6% higher frequency of survival for CS5E^(5D) and a 18-8% higher frequency of survival for CS5E^). Thus this experiment shows that the gene(s) conferring salt tolerance located on chromosome 5E^ has a greater affect when substituted for a homoeologous wheat group 5 chromosome than w^hen present as an additional chromosome, as in the 5E^ addition line (King et al, 1996).…”

“…The results of the experiment which were based on 96 plants per genotype, 48 plants in the control treatment and 48 in 175 mol m"^ NaCl, are shown in Table 2 (King et al, 1996). In the control treatments all plants reached maturit}?…”

“…This demonstrates the potential of the salt-tolerance gene, located on chromosome ^f rom Th. bessarabicum for the production of new salt-tolerant varieties of wheat (King et al, 1996).…”

“…bessarabicum chromosomes are required for good grain development in saltstressed conditions. Plants were grown to maturity at 18 °C with an 18 h photoperiod (King et al, 1996). pollinate. In order that monosomic and disomic substitution lines could be identified in the F^ and F3 generations genetic markers were identified which were specific to either the long arm of chromosomê (CS5E^L) or the short arm of chromosome…”

Breeding for abiotic stresses for sustainable agriculture

“…They also (Gorham et al 1986b) found variation in ion accumulation within and between many perennial Triticeae (reviewed in detail by King et al (1997a)). Proceeding through amphiploids ( Forster & Miller 1985;Gorham et al 1986a;Forster et al 1987), addition (Forster et al 1988) and substitution lines (King et al 1996), tolerance genes from T. bessarabicum were introduced into Chinese Spring. Field testing in Spain confirmed the high tolerance of the material (Gorham et al 1997), but so far the segment of the 5E b chromosome carrying tolerance has not been introduced into wheat without the linked deleterious genes.…”