Salinity stress is a critical abiotic stress that reduces crop productivity. Durum wheat (Triticum turgidum ssp. durum) is an essential cereal in Tunisia, a country threatened by salinity stress. In this study, 26 accessions of Tunisian durum wheat were subjected to salinity stress induced by 500 mM NaCl, and their salinity tolerance was evaluated by examining phenotypic parameters and calculating the salinity tolerance trait index and salinity tolerance index. Furthermore, two Tunisian durum wheat cultivars, namely ‘Om Rabia’ (salinity-tolerant) and ‘Mahmoudi’ (salinity-susceptible), were subjected to RNA sequencing (RNA-Seq) analysis, and single-nucleotide polymorphisms (SNPs) were detected from the RNA-Seq data of these two cultivars. The impacts of all SNP variants on genes were predicted, and 157 candidate SNP primer pairs were designed preferentially using high-impact transcripts. Following confirmation using polymerase chain reaction (PCR) analysis of data from ‘Om Rabia’ and ‘Mahmoudi’, 17 SNP markers were developed and applied to assess the remaining 26 Tunisian durum wheat lines. Three developed SNP markers (KUCMB_TRIDC7AG078450.6_12, KUCMB_TRIDC2BG061830.1_05, and KUCMB_TRIDC2BG061830.1_08) showed PCR bands only in salinity-tolerant lines but not in moderately tolerant or susceptible lines. Therefore, the developed SNP markers may be used to screen the salinity tolerance of various durum wheat accessions.

Salinity stress is a critical abiotic stress that reduces crop productivity. Durum wheat (Triticum turgidum ssp. durum) is an essential cereal in Tunisia, a country threatened by salinity stress. In this study, 26 accessions of Tunisian durum wheat were subjected to salinity stress induced by 500 mM NaCl, and their salinity tolerance was evaluated by examining phenotypic parameters and calculating the salinity tolerance trait index and salinity tolerance index. Furthermore, two Tunisian durum wheat cultivars, namely ‘Om Rabia’ (salinity-tolerant) and ‘Mahmoudi’ (salinity-susceptible), were subjected to RNA sequencing (RNA-Seq) analysis, and single-nucleotide polymorphisms (SNPs) were detected from the RNA-Seq data of these two cultivars. The impacts of all SNP variants on genes were predicted, and 157 candidate SNP primer pairs were designed preferentially using high-impact transcripts. Following confirmation using polymerase chain reaction (PCR) analysis of data from ‘Om Rabia’ and ‘Mahmoudi’, 17 SNP markers were developed and applied to assess the remaining 26 Tunisian durum wheat lines. Three developed SNP markers (KUCMB_TRIDC7AG078450.6_12, KUCMB_TRIDC2BG061830.1_05, and KUCMB_TRIDC2BG061830.1_08) showed PCR bands only in salinity-tolerant lines but not in moderately tolerant or susceptible lines. Therefore, the developed SNP markers may be used to screen the salinity tolerance of various durum wheat accessions.

Abstract We aimed to investigate the biological responses induced by acute and chronic gamma irradiation in colored wheat seeds rich in natural antioxidants. After acute and chronic irradiation, the phenotypic effects on plant growth, germination rate, seedling height, and root length were examined, and the biochemical changes were investigated by analyzing the expression of antioxidant enzyme-related genes, antioxidant enzyme activities, and total antioxidant capacity. High dosages of chronic radiation reduced plant growth compared with the controls. Electron spin resonance measurement and 2,2-diphenyl-1-picrylhydrazyl activity analysis showed lower amount of free radicals in colored wheat seeds on chronic irradiation with low dosage of gamma rays compared to seeds subjected to acute irradiation. Expression levels of anthocyanin biosynthesis genes, antioxidant-related genes, and antioxidant enzyme activity in seeds and young leaves of seedling showed diverse effects in response to different dosages and types of gamma irradiation. This suggests that phenotype is affected by the dosage and type of gamma radiation, and the phytochemicals in colored wheat seeds involved in antioxidant activity to scavenge free radicals respond differently to irradiation types. This provides evidence that acute and chronic exposure to radiation have different effects on seeds and young leaves after germination.

Abstract We aimed to investigate the biological responses induced by acute and chronic gamma irradiation in colored wheat seeds rich in natural antioxidants. After acute and chronic irradiation, the phenotypic effects on plant growth, germination rate, seedling height, and root length were examined, and the biochemical changes were investigated by analyzing the expression of antioxidant enzyme-related genes, antioxidant enzyme activities, and total antioxidant capacity. High dosages of chronic radiation reduced plant growth compared with the controls. Electron spin resonance measurement and 2,2-diphenyl-1-picrylhydrazyl activity analysis showed lower amount of free radicals in colored wheat seeds on chronic irradiation with low dosage of gamma rays compared to seeds subjected to acute irradiation. Expression levels of anthocyanin biosynthesis genes, antioxidant-related genes, and antioxidant enzyme activity in seeds and young leaves of seedling showed diverse effects in response to different dosages and types of gamma irradiation. This suggests that phenotype is affected by the dosage and type of gamma radiation, and the phytochemicals in colored wheat seeds involved in antioxidant activity to scavenge free radicals respond differently to irradiation types. This provides evidence that acute and chronic exposure to radiation have different effects on seeds and young leaves after germination.

Drought is a major stressor that severely hampers the production of many important crops. The short arm of rye (Secale cereale) chromosome 1 contains favourable stress-resistance alleles and is thus widely used in wheat (Triticum aestivum) breeding to generate 1BL.1RS translocation lines. In this study, 1BL.1RS-specific drought-responsive genes were identified using cDNA-amplified fragment length polymorphism (AFLP) analysis. Among the 144 transcript-derived fragments (TDF) differentially expressed in the 1BL.1RS line, we identified the function and chromosomal position of 84 TDF using public databases. Real-time PCR was performed to validate the results of cDNA-AFLP, and four TDF were significantly up-regulated. Furthermore, we developed two wheat-rye translocation-specific markers by comparing the TDF from the short arms of wheat and rye chromosome 1. One is specific to 1BL.1RS and the other is specific to 1AL.1RS and 1BL.1RS. Combinational use of both markers will be helpful to breed wheat possessing 1RS.

Drought is a major stressor that severely hampers the production of many important crops. The short arm of rye (Secale cereale) chromosome 1 contains favourable stress-resistance alleles and is thus widely used in wheat (Triticum aestivum) breeding to generate 1BL.1RS translocation lines. In this study, 1BL.1RS-specific drought-responsive genes were identified using cDNA-amplified fragment length polymorphism (AFLP) analysis. Among the 144 transcript-derived fragments (TDF) differentially expressed in the 1BL.1RS line, we identified the function and chromosomal position of 84 TDF using public databases. Real-time PCR was performed to validate the results of cDNA-AFLP, and four TDF were significantly up-regulated. Furthermore, we developed two wheat-rye translocation-specific markers by comparing the TDF from the short arms of wheat and rye chromosome 1. One is specific to 1BL.1RS and the other is specific to 1AL.1RS and 1BL.1RS. Combinational use of both markers will be helpful to breed wheat possessing 1RS.