Wild relatives of wheat have served as a pool of genetic variation for understanding salinity tolerance mechanisms. Two separate experiments were performed to evaluate the natural diversity in root and shoot Na+ exclusion and K+ accumulation, and the activity of four antioxidant enzymes within an extensive collection of ancestral wheat accessions. In the initial screening experiment, salinity stress (300 mm NaCl) significantly increased Na+ concentration in roots and leaves and led to a significant decline in root and shoot fresh weights, dry weights, and K+ contents. Principal component analysis of the 181 accessions and 12 species identified three first components accounted for 63.47% and 78.55% of the variation under salinity stress. We identified 12 accessions of each species with superior tolerance to salinity for further assessment of their antioxidant defence systems in response to salinity. Both mild (250 mm NaCl) and severe (350 mm NaCl) levels of salinity significantly increased activities of four enzymes, indicating an enhanced antioxidant-scavenging system for minimising the damaging effects of H2O2. Some of the wild relatives—Aegilops speltoides (putative B genome), Ae. caudata (C genome), Ae. cylindrica (DC genome) and Triticum boeoticum (Ab genome)—responded to salinity stress by increasing antioxidants as the dominant mechanism to retain oxidative balance in cells. Further evaluation of salt-tolerance mechanisms in these superior wild relatives will help us to understand the potential of wheat progenitors in the development of more salt-tolerant varieties.

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Glutenin and gliadin subunits play a key role in flour processing quality by network formation in dough. Wild relatives of crops have served as a pool of genetic variation for decades. In this study, 180 accessions from 12 domesticated and wild relatives of wheat were characterized for the glutenin and gliadin genes with allele-specific molecular markers. A total of 24 alleles were detected for the Glu-A3 and Gli-2A loci, which out of 19 amplified products identified as new alleles. Analysis of molecular variance (AMOVA) indicated that 90 and 65% of the genetic diversity were partitioned within two Aegilops and Triticum genera and their species, respectively. Furthermore, all glutenin and gliadin analyzed loci were polymorphic, indicating large genetic diversity within and between the wild species. Our results revealed that allelic variation of Glu-3A and Gli-As.2 is linked to genomic constitutions so that, Ae. caudata (C genome), Ae. neglecta (UM genome), Ae. umbellulata (U genome) and T. urartu (A u genome) harbor wide variation in the studied subunits. Hence, these species can be used in wheat quality breeding programs.

In this study, target region amplification polymorphism (TRAP) and conserved region amplification polymorphism (CoRAP) markers were used for genetic diversity and relationship analysis of 25 Salvia ecotypes/species. Twelve TRAP and CoRAP primer combinations (four arbitrary primers and three fixed primers from Salvia miltiorrhiza expressed sequence tag sequences) amplified 180 loci, of which all were polymorphic. The obtained high average PIC and MI values revealed high capacity of TRAP and CoRAP primers to detect polymorphic loci among Salvia species. TRAPs and CoRAPs had similar efficiency in detecting polymorphisms with excellent ability to differentiate the closely related Salvia ecotypes. Based on both TRAP and CoRAP data, tetraploid Salvia virgata (2n ¼ 4x ¼ 32) showed the highest values for Na (1.17, 1.29), Ne (1.29, 1.35), Shannon index (0.26, 0.32) and heterozygosity (0.172, 0.212) in all 11 studied species. The Nei's genetic distances with TRAPs and CoRAPs ranged from 0.23 to 0.69 and 0.19 to 0.64, respectively. The tree pattern based on combined CoRAP þ TRAP data with the neighbour joining method clustered 25 Salvia species/ecotypes into five major groups that showed good alignment with the population structure analysis results. In both TRAPs and CoRAPs data analysis of molecular variance (AMOVA), the estimated variance within Salvia species was greater than that among Salvia species.