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Hexaploid synthetic wheat, derived from crosses between durum wheat and Aegilops tauschii, is widely accepted as an important source of useful traits for wheat breeding. During 2015 and 2016, three groups of synthetics were studied in Azerbaijan (3 sites) and Russia (1 site). Group 1 comprised CIMMYT primary synthetics derived from eastern European winter durum wheats crossed to Ae. tauschii accessions from the Caspian Sea basin. Group 2 included lines derived from CIMMYT synthetics × bread wheat crosses. Group 3 consisted of synthetics developed in Japan by crossing durum variety Langdon with a diverse collection of Ae. tauschii accessions. Varieties Bezostaya-1 and Seri were used as checks. Group 1 synthetics were better adapted and more productive than those in group 3, indicating that the durum parent plays an important role in the adaptation of synthetics. Compared to Bezostaya-1 synthetics produced fewer spikes per unit area, an important consideration for selecting bread wheat parents for maintenance of productivity. Synthetics had longer spikes but were not generally free-threshing. All synthetics and derivatives had 1000-kernel weights comparable to Bezostya-1 and significantly higher than Seri. All primary synthetics were resistant to leaf rust, several to stem rust, and few to stripe rust. Superior genotypes from all three groups that combine high expression of spike productivity traits and stress tolerance index were identified.

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We aimed to study the influence of soil water deficit on gas exchange parameters, dry matter partitioning in leaves, stem and spike and grain yield of durum (Triticum durum Desf.) and bread (Triticum aestivum L.) wheat genotypes in the 2013–2014 and 2014–2015 growing seasons. Water stress caused reduction of stomatal conductance, photosynthesis rate, transpiration rate, an increase of intercellular CO2 concentration. Photosynthesis rate positively correlated with growth rate of genotypes. Drought stress caused adaptive changes in dry matter partitioning between leaves, stem and spike of wheat genotypes. Stem dry mass increased until kernel ripening. Drought stress accelerated dry mass reduction in leaves and stem. High growth rate of spike dry mass was revealed in genotypes with late heading time. Spike dry mass positively correlated with photosynthesis rate and grain yield. Generally, bread wheat is more productive and tolerant to drought stress than durum wheat.

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During the last century wheat landraces were replaced by modern wheat cultivars leading to a gradual process of genetic erosion. Landraces genotyping and phenotyping are strategically useful, as they could broaden the genetic base of modern cultivars. In this research, we explored Single Nucleotide Polymorphism (SNP) markers diversity in a collection of common and durum wheats, including both landraces and Italian elite cultivars. A panel of 6,872 SNP markers was used to analyze the genetic variability among the accessions, using both the Principal Components Analysis (PCA) and the Neighbour Joining clustering method. PCA analysis separated common wheat accessions from durum ones, and allowed to group separately durum landraces from durum elite cultivars. The Neighbour joining clustering validated PCA results, and moreover, separated common wheat landraces from common elite cultivars. The clustering results demonstrated that Italian durum landraces were poorly exploited in modern breeding programs. Combining cluster results with heterozygosity levels observed, it was possible to clarify synonymy and homonymy cases identified for Bianchetta, Risciola, Saragolla, Timilia and Dauno III accessions. The SNP panel was also used to detect the minimum number of markers to discriminate the studied accessions. A set of 33 SNPs were found to be highly informative and used for a molecular barcode, which could be useful for cultivar identification and for the traceability of wheat end-products.

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Grains of 12 accessions of Triticum timopheevii (Zhuk.) Zhuk. ssp. timopheevii (AAGG, 2n = 4x = 28) and one bread wheat cultivar Chinese Spring (CS) and one durum wheat cultivar Langdon (LDN) grown across two years were analyzed for grain iron (Fe) and zinc (Zn) concentrations. All the 12 tested T. timopheevii ssp. timopheevii genotypes showed significantly higher concentration of grain Fe and Zn than CS and LDN. Aboundant genetic variability of both the Fe and Zn concentrations was observed among the T. timopheevii ssp. timopheevii accessions, averagely varied from 47.06 to 90.26 mg kg−1 and from 30.05 to 65.91 mg kg−1, respectively. Their grain Fe and Zn concentrations between years exhibited a significantly positive correlation with the correlation coefficients r = 0.895 and r = 0.891, respectively, indicating the highly genetic stability. Flag leaf possessed twice or three times higher concentrations for both Fe and Zn than grain, and a significantly high positive correlation appeared between the two organs with r = 0.648 for Fe and r = 0.957 for Zn concentrations, respectively, suggesting flag leaves might be indirectly used for evaluating grain Zn and Fe contents. Significant correlations occurred between grain Fe and Zn concentrations, and between grain Zn concentration and the two agronomic traits of plant height and number of spikelets per spike. Both the concentrations were not related to seed size or weight as well as NAM-G1 gene, implying the higher grain Fe and Zn concentrations of T. timopheevii ssp. timopheevii species are not ascribed to concentration effects of seed and the genetic control of NAM-G1 gene. There might be some other biological factors impacting the grain’s Zn and Fe concentrations. These results indicated T. timopheevii ssp. timopheevii species might be a promising genetic resource with high Fe and Zn concentrations for the biofortification of current wheat cultivars.

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. Araus , J.L. , Amaro , T. , Casadesús , J. , Asbati , A. , Nachit , M.M. 1998 . Relationships between ash content, carbon isotope discrimination and yield in durum wheat . Functional Plant Biol. 25 : 835 – 842

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Aguirano, E., Ruiz, M., Fitè, R., Carrillo, J.M. 2008. Genetic variation for glutenin and gliadins associated with quality in durum wheat ( Triticum turgidum L. ssp. turgidum ) landraces from Spain. Span. J

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.S. 1983 . A modified screening test for rapid estimation of gluten strength in early-generation durum wheat breeding lines . Cereal Chem. 60 : 315 – 318 Gupta , R.B. , MacRitchie , F

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FHB of wheat is a serious regional problem in Punjab. An outstanding bread wheat line RP-1/10 and three durum lines viz; WH 896, HD 4715 and MPO 1192-resistant to FHB have been identified. Aphids are important insect-pests in wheat and the FHB severity can be significantly reduced by more than 30%, by controlling these aphids by the application of Monocrotophos (insecticide) at boot + heading or at heading alone. A single application of Monocrotophos @ 0.1% followed 72h later by Tilt@0.1% at heading significantly improved FHB control and grain yield. The strobilurin fungicide-Amistar@ 0.1%, applied as a single spray at heading, was the best treatment in reducing FHB severity and improving grain yield. The efficacy of the fungicide was much higher in bread wheat compared to durum wheat. The results suggest that wheat aphids are important in FHB development and their management through insecticide in combination with fungicide can reduce FHB and improve grain yield.

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” — Part 2: Routine Method . International Organization for Standardization. Geneva, Switzerland . ISO 3093 . 2004 . Wheat, Rye and Respective Flours, Durum Wheat and durum Wheat Semolina — Determination of the

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. Hafsi , M. , Mechmeche , W. , Bouamama , L. , Djekoune , A. 2000 . Flag leaf senescence as evaluated by numerical image analysis and its relationship with yield under drought in durum wheat . J. Agron. Crop Sci. 185 : 275 – 280

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