The main goal of this study was to investigate the genetic basis of yield and grain quality traits in winter wheat genotypes using association mapping approach, and identify linked molecular markers for marker assisted selection. A total of 120 elite facultative/winter wheat genotypes were evaluated for yield, quality and other agronomic traits under rain-fed and irrigated conditions for two years (2011–2012) at the Tel Hadya station of ICARDA, Syria. The same genotypes were genotyped using 3,051 Diversity Array Technologies (DArT) markers, of which 1,586 were of known chromosome positions. The grain yield performance of the genotypes was highly significant both in rain-fed and irrigated sites. Average yield of the genotypes ranged from 2295 to 4038 kg/ha and 4268 to 7102 kg/ha under rain-fed and irrigated conditions, respectively. Protein content and alveograph strength (W) ranged from 13.6–16.1% and 217.6–375 Jx10-4, respectively. DArT markers wPt731910 (3B), wPt4680 (4A), wPt3509 (5A), wPt8183 (6B), and wPt0298 (2D) were significantly associated with yield under rain-fed conditions. Under irrigated condition, tPt4125 on chromosome 2B was significantly associated with yield explaining about 13% of the variation. Markers wPt2607 and wPt1482 on 5B were highly associated with protein content and alveograph strength explaining 16 and 14% of the variations, respectively. The elite genotypes have been distributed to many countries using ICARDA’s International system for potential direct release and/or use as parents after local adaptation trials by the NARSs of respective countries. The QTLs identified in this study are recommended to be used for marker assisted selection after through validation using bi-parental populations.

SUMMARY: A collection of 26 wheat genotypes widely grown in Spain during the 20th century was evaluated in eight contrasting environments in order to quantify breeding achievements in yield and associated traits. From 1930 to 2000, yield increased at a rate of 35·1 kg/ha/yr or 0·88%/yr, but estimations of relative genetic gain (RGG) were environment-dependent. RGG estimated for yield were positively associated with the average minimum daily temperatures from sowing to heading in the testing environments (R² = 0·81;P < 0·01). The number of grains/spike and the number of spikes/m²increased at a rate of 0·60%/yr and 0·30%/yr, respectively, while grain weight remained unchanged. The present study detected two main episodes of yield improvement during the century. The first one coincided with the introduction, during the 1950s, of the first improved cultivars derived from intra-specific crosses, which increased the yield of landraces by 30% due to an increase ofc. 58% in the number of grains/spike, accompanied by a 16% reduction in grain weight. These initial cultivars (termed ‘old-bred’ in a previous study by Sanchez-Garciaet al. 2012) exhibited a higher harvest index (HI), increased from 0·25 to 0·40, but maintained the same aboveground biomass at maturity as the landraces (despite reducing both plant height and the number of tillers/plant) due to increases in the proportion of tillers bearing spikes. The second yield gain occurred after the introduction, in the early 1970s, of semi-dwarf germplasm from CIMMYT (International Maize and Wheat Improvement Centre) and some French cultivars. This new germplasm further reduced plant height, improved HI up to 0·45 and increased the number of tillers/plant while maintaining their rate of fertility, thus resulting in a yield gain ofc. 37%. The cultivars released during the last decade of the century did not contribute to significant yield improvements.

Genetic gains in quality traits were assessed in grain samples from 4 field experiments involving 16 bread wheat varieties representative of those most widely cultivated in Spain during the 20th century. The allelic composition at three glutenin loci (Glu-A1, Glu-B1, and Glu-D1) was obtained by PCR-based DNA markers and published references. From 1930 to 2000 grain protein content decreased by −0.030%y−1, or in relative terms by −0.21%y−1, but the protein produced per hectare increased by 0.39%y−1. Alveographic tests revealed significant changes in dough rheological properties. Dough strength (W) and tenacity (P) increased at relative rates of 1.38%y−1 and 0.99%y−1, respectively, while dough extensibility (L) decreased by −0.46%y−1, resulting in an increase of 1.45%y−1in dough equilibrium (P/L). The rise in protein quality could be related to the replacement of the null allele by subunits 1 or 2* at Glu-A1 and the prevalence of subunits 7+8 and 5+10 at Glu-B1 and Glu-D1 loci, respectively, in the most recent varieties. Dough extensibility was affected by water input during the crop cycle, this relationship being partially explained by the presence of the 5+10 HMW glutenin subunit. Fermentation tolerance was improved in the most modern varieties. Collapse during fermentation was avoided only in doughs with a W≥159 J×10−4 and a P/L≥0.56mm H2O mm−1, levels achieved by most of the modern varieties. The over-strong and unbalanced rheological properties of some modern varieties resulted in highly porous doughs, and no clear advances in dough maximum height during fermentation were attained

Durum wheat (Triticum durum Desf.) is the 10th most important crop in the world, and its cultivation occurs on a vast array of international agroenvironments. However, its wide international adaptation is only marginally documented. Here, 24 durum wheat genotypes comprising elites from the ICARDA breeding program and commercial checks were assessed at 27 field stations located in 18 countries. Analysis of variance revealed significant environment, genotype, and genotype × environment (GxE) effects for phenology, height, grain yield, and grain size, with genotype and GxE explaining 1 and 9.6% of the total grain yield variation, respectively. Heritability was recorded at 0.6 for grain yield. Only late maturity and extended grain filling‐period had a negative effect on grain yield (r = −0.67, p < 0.01). A matrix of correlation between traits was used for hierarchical clustering to identify four main agroenvironments. At 26 of the stations, the elite genotypes of ICARDA were able to outyield the best commercial check. Two stability analysis (Finlay–Wilkinson and additive main effects and multiplicative model wide adaptation index) were used in combination with average grain yield performances to identify the three most stable and widely adapted elite lines, which were given the cross names ‘Derazejihan’, ‘Kundermiki’, and ‘Bezajihan’. The results gathered here support the usefulness of stability‐based indices, the good performances of the ICARDA germplasm, and the need for more coordinated international efforts for this crop.

Heat stress decreases photosynthesis, pollen viability, and grain number and weight and hence lowers yield and quality of wheat (Triticum aestivumL.) by variable amounts among different cultivars and genotypes. The present study was performed to determine genetic variability of spring bread wheat genotypes for yield and other agronomic traits under heat‐stressed (Wad Medani, Sudan) and high‐yielding (Sids, Egypt) environments and to identify linked single nucleotide polymorphism (SNP) markers through association mapping. A heat association panel of 197 spring wheat genotypes from ICARDA was evaluated for yield and agronomic traits at Wad Medani and Sids stations for 2 yr (2014–2015). A total of 111 significant marker‐trait associations were detected. The wsnp_Ex_c12812_20324622 marker on chromosome 4A was significantly correlated with yield at both locations. At Wad Medani, wsnp_Ex_c2526_4715978 on chromosome 5A was significantly correlated with grain yield. Wheat genotypes carrying the cytosine base at the wsnp_Ex_c12812_20324622 and wsnp_Ex_c2526_4715978 markers outyielded the ones carrying the alternative bases by 15%, whereas genotypes carrying the cytosine base at only one of the two markers increased their yield by 7.9 to 10%, suggesting the importance of using these markers for marker‐assisted selection in breeding programs to increase yield under heat stress. The top 20 high‐yielding and heat‐tolerant genotypes identified in this study have been distributed to the national research systems of Central and West Asia and North Africa (CWANA) and sub‐Saharan Africa (SSA) for potential direct release and/or use as parents after local adaptation trials.

Barley is a very important crop particularly in marginal dry areas, where it often serves as the most viable option for farmers. Additionally, barley carries great significance in the Western world, serving not only as a fundamental crop for animal feed and malting but also as a nutritious food source. The broad adaptability of barley and its ability to withstand various biotic and abiotic stresses often make this species the sole cereal that can be cultivated in arid regions. The collection and utilization of barley genetic resources are crucial for identifying valuable traits to enhance productivity and mitigate the adverse effects of climate change. This review aims to provide an overview of the management and exploitation of barley genetic resources. Furthermore, the review explores the relationship between gene banks and participatory breeding, offering insights into the diversity and utilization of barley genetic resources through some examples such as the initiatives undertaken by ICARDA. Finally, this contribution highlights the importance of these resources for boosting barley productivity, addressing climate change impacts, and meeting the growing food demands in a rapidly changing agriculture. The understanding and utilizing the rich genetic diversity of barley can contribute to sustainable agriculture and ensure the success of this vital crop for future generations globally.