The effects of salt stress on growth parameters, free proline content, ion accumulation, lipid peroxidation, and several antioxidative enzymes activities were investigated in S. persica and S. europaea. The seedlings were grown for 2 months in half-strength Hoagland solution and treated with different concentrations of NaCl (0, 85, 170, 340, and 510 mM) for 21 days. The fresh and dry weights of both species increased significantly at 85 and 170 mM NaCl and decreased at higher concentrations. Salinity increased proline content in both the species as compared to that of control. Sodium (Na ? ) content in roots and shoots increased, whereas K ? and P i content in both organs decreased. At all NaCl concentrations, the total amounts of Na ? and K ? were higher in shoots than in roots. Malondialdehyde (MDA) content declined at moderate NaCl concentrations (85 and 170 mM) and increased at higher levels. With increased salinity, superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (GPX) activities also increased gradually in both species. In addition, it seems that GPX, CAT, and SOD activities play an essential protective role in the scavenging reactive oxygen species (ROS) in both species. Native polyacrylamide gel electrophoresis (PAGE) indicated different isoform profiles between S. persica and S. europaea concerning antioxidant enzymes. These results showed that S. persica exhibits a better protection mechanism against oxidative damage and it is more salt-tolerant than S. europaea possibly by maintaining and/or increasing growth parameters, ion accumulation, and antioxidant enzyme activities.

Two of the important traits for wheat yield are tiller and fertile tiller number, both of which have been thought to increase cereal yield in favorable and unfavorable environments. A total of 6,349 single nucleotide polymorphism (SNP) markers from the 15 K wheat Infinium array were employed for genome-wide association study (GWAS) of tillering number traits, generating a physical distance of 14,041.6 Mb based on the IWGSC wheat genome sequence. GWAS analysis using Fixed and random model Circulating Probability Unification (FarmCPU) identified a total of 47 significant marker-trait associations (MTAs) for total tiller number (TTN) and fertile tiller number (FTN) in Iranian bread wheat under different water regimes. After applying a 5% false discovery rate (FDR) threshold, a total of 13 and 11 MTAs distributed on 10 chromosomes were found to be significantly associated with TTN and FTN, respectively. Linked single nucleotide polymorphisms for IWB39005 (2A) and IWB44377 (7A) were highly significantly associated (FDR < 0.01) with TTN and FTN traits. Moreover, to validate GWAS results, meta-analysis was performed and 30 meta-QTL regions were identified on 11 chromosomes. The integration of GWAS and meta-QTLs revealed that tillering trait in wheat is a complex trait which is conditioned by the combined effects of minor changes in multiple genes. The information provided by this study can enrich the currently available candidate genes and genetic resources pools, offering evidence for subsequent analysis of genetic adaptation of wheat to different climatic conditions of Iran and other countries. Bread wheat (Triticum aestivum L., genomes AABBDD, 2n = 6x = 42), is a major cereal crop, supplying 20% of the total energy and protein of the world's diet 1. Its production and productivity, especially in arid and semiarid regions such as Iran, are considerably constrained by extreme drought and heat stresses. Breeding for grain yield is the final step to produce stress-tolerant crop plants, since grain yield is a complex trait with low heritability, which is controlled by multiple genes and is affected by a lot of environmental factors, other traits such as yield components can be employed to overcome the limitations. Tillering is a crucial factor for wheat yield because of its involvement in grain weight and grain number determination. Moreover, it is a determinant of grain yield,

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