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The development and deployment of diverse resistance sources in new wheat cultivars underpin the durable control of stripe rust. In the present study, two loci for adult plant resistance (APR), QYrSM155.1 and QYrSM155.2, were identified in the Chinese wheat breeding line Shaanmai 155. QYrSM155.1 was mapped to a 3.0-cM interval between the single-nucleotide polymorphism (SNP) markers AX-109583610 and AX-110907562 on chromosome arm 2BL. QYrSM155.2 was mapped to a 2.1-cM interval flanked by the SNP markers AX-110378556 and AX-86173526 on chromosome arm 7AS. A genome-wide association study was used to identify markers associated with APR in a panel of 411 spring wheat lines. Thirteen and 11 SNPs were significantly associated with QYrSM155.1 and QYrSM155.2, respectively, corresponding to physical intervals of 653.75–655.52 Mb on 2BL and 81.63–83.93 Mb on 7AS. To characterize the haplotype variation and the distribution of these QTL, haplotype analysis was performed based on these SNPs in an independent panel of 1,101 worldwide wheat accessions. Three major haplotypes (2B_h1, 2B_h2, and 2B_h3) for QYrSM155.1 and four major haplotypes (7A_h1, 7A_h2, 7A_h3, and 7A_h4) for QYrSM155.2 were identified. Accessions individually harboring QYrSM155.1_h1 and QYrSM155.2_h1 haplotypes and their combination displayed resistance. Additional assays of 1,306 current Chinese cultivars and breeding lines using markers flanking QYrSM155.1 and QYrSM155.2 indicated that the resistance haplotypes of the two QTL were present in respectively 1.45% and 14.16% of lines. Increasing resistance haplotype frequencies at these two loci using marker-assisted selection should benefit wheat production in China.

Leaf rust (LR) and stripe rust (YR) are important diseases in wheat producing areas worldwide and cause severe yield losses under favorable environmental conditions when susceptible varieties are grown. We determined the genetic basis of resistance to LR and YR in variety Borlaug 100 by developing and phenotyping a population of 198 F6 recombinant inbred lines derived from a cross with the susceptible parent Apav#1. LR and YR phenotyping were conducted for 4 and 3 seasons, respectively, at CIMMYT research stations in Mexico under artificial epidemics. Mendelian segregation analyses indicated that 3–5 LR and 2 YR genes conferred resistance in Borlaug 100. Lr46/Yr29 (1BL), Yr17 (2AS) and Yr30 (3BS) were present in the resistant parent and segregated in the RIL population based on characterization by molecular markers linked to these genes. When present alone, Lr46/Yr29 caused average 13% and 16% reductions in LR and YR severities, respectively, in RILs. Similarly, Yr17 and Yr30 reduced YR severities by 57% and 11%, respectively. The Yr30 and the Yr17 translocation were also associated with 27% and 14% reductions, respectively, in LR severity, indicating that the 3BS and 2AS chromosomal regions likely carry new slow rusting LR resistance genes, temporarily designated as LrB1 and LrB2, respectively. Additive effects of Yr30*Yr17, Yr29*Yr17 and Yr29*Yr30 on YR and LR were significant and reduced YR severities by 56%, 55%, and 45%, respectively, and LR severities by 34%, 40%, and 45%, respectively. Furthermore, interaction between the three genes was also significant, with mean reductions of 70% for YR and 54% for LR severities. Borlaug 100, or any one of the 21 lines with variable agronomic traits but carrying all three co-located resistance loci, can be used as resistance sources in wheat breeding programs.

Bread wheat is a major staple cereal provides more than 20% of dietary energy and protein supply to global population. However, with increasing population growth, the problem of nutritional deficiencies is increasingly affecting the health of resource people with predominantly cereal-based diet. Therefore, the development of wheat genotypes with micronutrient-dense grains along with high-yield potential is one of the major priorities of wheat biofortification program at CIMMYT. We conducted a QTL mapping study using a recombinant inbred line (RIL) population derived from a cross between a Chinese parental line with highGZnC and a Mexican commercial bread wheat cultivar Roelfs F2007 to identify QTLs that could potentially be integrated in mineral nutrient concentrations and agronomic-related traits breeding. We evaluated 200 RIL lines for mineral nutrient concentrations and agronomic-related traits over two years. A total of 60 QTLs were detected, of which 10 QTLs for GZnC, 9 for GFeC, 5 for GPC and 36 for agronomic-related traits. Moreover, a total of 55 promising candidate genes were identified from the list of associated markers for GFeC and GZnC using the recently annotated wheat genome sequence. We identified the promising genomic regions with high mineral nutrient concentrations and acceptable yield potential, which are good resource for further use in wheat biofortification breeding programs., Highlights • Rich genetic diversity for micronutrients in wheat landraces provides novel alleles. • QTLs identified for multiple traits offers breeding competitive biofortified wheat. • Genomic regions and the candidate genes identified enables marker assisted breeding.

This paper applies reflectance spectroscopy and Advanced Space borne thermal emission reflection radiometer (ASTER) data processing to delineate dolomite-hosted rock phosphate around Udaipur City, Western India, using visible-near infrared (VNIR) and short wave infrared (SWIR) bands of the ASTER sensor. A number of ASTER image spectra and field spectra (resampled to ASTER bands) of pure dolomite and rock phosphate are compared and found to be consistent in terms of the presence of absorption minima at 2.3 µm for dolomite and the absence of the same feature in the spectra of the rock-phosphate. Before attempting spectral mapping, ASTER SWIR band data are clipped using the spatial extent of host rock; which has been prepared from the reference geological map and consequently updated using VNIR-SWIR derived image enhanced products at selected part of the study areas. Two sub-pixel spectral methods namely adaptive coherence estimator (ACE) and matched filtering (MF) methods are applied to ASTER SWIR bands to delineate rock-phosphate-rich zones within dolomite. The output images of the above algorithms are integrated in a principal component (PC) image to delineate phosphate pixels. A principal component; which has similar sign of Eigen vector loading for ACE and MF abundance image is used to delineate rock phosphate within dolomite. The results are validated in the field using a qualitative colorimetric method and also by comparing image spectra of spectrally anomalous zone with the ASTER resampled laboratory spectra of rock phosphate samples. A number of sporadic but important patches of phosphate rich zones in addition to the main surface exposures of the Jhamar Kotra Mine are confirmed in the field. The proposed method is a novel application of spectral mapping of phosphate deposits in dolomitic and carbonatic rocks and present approach of ASTER data processing can be used to delineate phosphate rich zones occurring within similar geological provinces in any parts of the world.

The paper compares food and straw fodder traits in wheat lines of 6 different CIMMYT wheat trials tested across 32 environments of South Asia (India, Nepal, Bangladesh and Pakistan). Experiments were conducted in the main spring wheat season with sowing time of mid-November to mid-December and harvest between March to April. Investigated and compared were grain yield (GY), straw yield (SY), straw nitrogen (N) content, neutral (NDF) and acid (ADF) detergent fiber, acid detergent lignin (ADL), and in vitro organic matter digestibility (IVOMD). Highly significant (P 60%), considerable (45%) for HI and straw N (40%), moderate for ADL (18%), and minor for NDF, ADF, and IVOMD ( Across all cultivar types only ADF was significantly (P 0.05) relationships were observed between N, ADF and IVOMD and SY. Among cultivars consistent relationships were only observed between N and GY which were significantly (P = 0.03 to 0.009) inversely correlated in five out of the six cultivar types. Within cultivars types ADF varied by at least 2.3% units in HTNM and 1st DRYT and up to 4.9% units in ESWYT. By extrapolation such cultivar-dependent differences will matter at wheat straw trading.

Fifty wheat lines targeting semi-arid locations in India and Bangladesh were investigated for grain and straw yield and straw fodder quality traits for two consecutive years at two locations in India and one in Bangladesh. Fodder traits investigated were nitrogen (N), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), in vitro organic matter digestibility (IVOMD), and metabolizable energy content (ME). Highly significant (P

Agronomic systems based on zero tillage and residue retention are becoming more important due to their potential for climate change adaptation through the reduction of soil erosion and improved water availability. Denser soil surface conditions and large amounts of crop residues, however, may be a constraint for early plant establishment, especially in irrigated production areas with high yield potential. Genotype by tillage interactions for yield are not well understood and it is unknown whether tillage should be an evaluation factor in breeding programs. Twenty-six CIMMYT bread ( Triticum aestivum ) and durum ( Triticum turgidum ) wheat genotypes, created between 1964 and 2009, were tested for yield and agronomic performance at CIMMYT’s experimental station near Ciudad Obregon, Mexico, over six years. Treatments included conventional and permanent raised beds with full and reduced irrigation. The objectives were to study breeding progress in distinct agronomic systems and to elucidate the importance of tillage and genotype by tillage interaction for yield and agronomic traits. Breeding progress was achieved irrespective of agronomic treatment. Tillage influenced plant growth and number of grains per m 2 in both wheat types. In bread wheat, genotype by tillage interaction was significant for yield, test weight, and growth parameters. However, no cross-over effects were detected and rank changes were small. In durum wheat, genotype by tillage interaction was only significant for plant growth. The results do not indicate the need for separate breeding programs. However, the question of a need for selection under zero tillage to increase breeding progress is yet to be answered.

The CIMMYT wheat breeding program aims to develop bread wheat (Triticum aestivum L.) genotypes that have superior grain yields, disease resistance and stress tolerance, along with appropriate quality to satisfy all stakeholders of the wheat value chain. Grain quality for wheat consists of a combination of many defined parameters including grain morphological characteristics, dough and final products properties, all of which are defined by the genotype, the environment and their interactions. Our current approach for improving grain quality is to study grain samples obtained under high yield potential environments with optimum management. To assess the effect of this strategy on quality under stressed environments, 54 genotypes were evaluated for two years under six environmental conditions, including drought and heat stress. Grain morphology (grain density and size), protein content and flour yield were severely affected by the environment, as drought and heat stress had a strong negative effect on all of these characteristics except protein content. Gluten quality (strength and extensibility) was defined more by the genotype, although the environmental effects and the interactions were also important, particularly for gluten extensibility. The current selection strategy for quality traits carried out under optimum conditions was found to be suitable to ensure high quality characteristics across several environments for most of the parameters with an overall positive outcome.

Genomic selection (GS) facilitates the rapid selection of superior genotypes and accelerates the breeding cycle. In this review, we discuss the history, principles, and basis of GS and genomic-enabled prediction (GP) as well as the genetics and statistical complexities of GP models, including genomic genotype × environment (G × E) interactions. We also examine the accuracy of GP models and methods for two cereal crops and two legume crops based on random cross-validation. GS applied to maize breeding has shown tangible genetic gains. Based on GP results, we speculate how GS in germplasm enhancement (i.e., prebreeding) programs could accelerate the flow of genes from gene bank accessions to elite lines. Recent advances in hyperspectral image technology could be combined with GS and pedigree-assisted breeding.

4-Methylidene substituted oxazolines are shown to be suitable substrates in thermal ene reactions with a variety of common enophiles. These pre-aromatic heterocycles provide access to a variety of adducts in modest to good yields. Interestingly, reaction with nitrosobenzene led to the formation of nitrones rather than the anticipated hydroxyl amine derivatives.

An investigation of the dearomatization reactions of benzylic thioureas, ureas and guanidines using hypervalent iodine reagents is described. Initial attempts to perform this reaction with methyl aryl ethers was compromised by electrophilic addition leading to the formation of benzo[d]thiazoles. However, inverting the direction of the process and oxidizing the corresponding phenol delivered the desired spiro fused heterocycles in moderate to good yields for all three families.

The Global Wheat Program, now managed by the CGIAR consortium and led by CIMMYT, initiated wheat breeding about 70 years ago in Mexico. Currently, the key objectives are to develop wheat cultivars that have superior grain yield, durable disease resistance, drought and heat tolerance and meet the processing and end-use quality needs for diverse worldwide processing conditions and products. In this study, the genetic gains in grain quality of semi-dwarf spring wheat cultivars developed from 1965 to 2015 by CIMMYT and related breeding programs of national partners in the target areas were examined. Genetic gains for test weight, thousand kernel weight, grain hardness, flour yield, gluten extensibility and protein content were non-significant, and these traits remained stable despite grain yield increase over years. Positive genetic gains were found for dough strength related parameters mixograph mixing time (0.026 min. per year), torque (0.93 per year) and alveograph W (2.31 J*10–4 per year), and bread-making quality (loaf volume, 1.32 mL per year). We concluded that genetic gains for grain yield of CIMMYT spring wheat cultivars demonstrated by previous studies were not at the expense of processing and end-use quality traits. Both types of traits have been improved in the last 50 years through direct selection ensuring the acceptability of CIMMYT germplasm in the target countries by all wheat value chain stakeholders.

The International Center for Maize and Wheat Improvement (CIMMYT) leads the Global Wheat Program, whose main objective is to increase the productivity of wheat cropping systems to reduce poverty in developing countries. The priorities of the program are high grain yield, disease resistance, tolerance to abiotic stresses (drought and heat), and desirable quality. The Wheat Chemistry and Quality Laboratory has been continuously evolving to be able to analyze the largest number of samples possible, in the shortest time, at lowest cost, in order to deliver data on diverse quality traits on time to the breeders for making selections for advancement in the breeding pipeline. The participation of wheat quality analysis/selection is carried out in two stages of the breeding process: evaluation of the parental lines for new crosses and advanced lines in preliminary and elite yield trials. Thousands of lines are analyzed which requires a big investment in resources. Genomic selection has been proposed to assist in selecting for quality and other traits in breeding programs. Genomic selection can predict quantitative traits and is applicable to multiple quantitative traits in a breeding pipeline by attaining historical phenotypes and adding high-density genotypic information. Due to advances in sequencing technology, genome-wide single nucleotide polymorphism markers are available through genotyping-by-sequencing at a cost conducive to application for genomic selection. At CIMMYT, genomic selection has been applied to predict all of the processing and end-use quality traits regularly tested in the spring wheat breeding program. These traits have variable levels of prediction accuracy, however, they demonstrated that most expensive traits, dough rheology and baking final product, can be predicted with a high degree of confidence. Currently it is being explored how to combine both phenotypic and genomic selection to make more efficient the genetic improvement for quality traits at CIMMYT spring wheat breeding program.

Mining of new genetic resources is of paramount importance to combat the alarming spread of stripe rust disease and breakdown of major resistance genes in wheat. We conducted a genome wide association study on 352 un-utilized Afghan wheat landraces against stripe rust resistance in eight locations. High level of disease variation was observed among locations and a core-set of germplasm showed consistence performance. Linkage disequilibrium (LD) decayed rapidly (R2≈0.16 at 0cM) due to germplasm peerless diversity. The mixed linear model resulted in ten marker-trait associations (MTAs) across all environments representing five QTL. The extensively short LD blocks required us to repeat the analysis with less diverse subset of 220 landraces in which R2 decayed below 0.2 at 0.3cM. The subset GWAS resulted in 36 MTAs clustered in nine QTL. The subset analysis validated three QTL previously detected in the full list analysis. Overall, the study revealed that stripe rust epidemics in the geographical origin of this germplasm through time have permitted for selecting novel resistance loci.

Arabinoxylans (AX) are the major components of dietary fibers (DF) in wheat grain and their consumption has been associated with multiple health benefits. Selection of wheat varieties with higher AX content could be an efficient approach to improve the daily consumption of DF. Here, the genetic variability of the total (TOT-AX) and water-extractable arabinoxylans (WE-AX) present in refined flour was investigated using a panel of 175 common wheat lines. Wide variation in both TOT-AX (10.79–16.54 mg/g) and WE-AX (3.19–7.63 mg/g) was found across the panel, with the genotype explaining a greater percentage of AX variation compared to the environment. Genomic regions associated with AX were investigated through genome-wide association study (GWAS) which revealed the association of five SNPs on chromosomes 1BL and 5BS with TOT-AX, and of 13 SNPs on chromosomes 1BL, 2BS, 6BS, 7A and 7BL with WE-AX. Markers on chromosome 1BL were coincident for both the AX fractions and explained the greatest percentage of phenotypic variation (13.29–17.22% for TOT-AX; 11.56–19.37% for WE-AX). In silico analysis of the genomic region delimited by the most significant 1BL markers (~8 Mb) identified a predicted gene encoding for a glycosyl transferase (GT) of the GT61 family which is likely a candidate gene associated with the observed AX variation. Lastly, the four most significant 1BL GBS markers identified through the GWAS analysis were translated into Kompetitive allele specific PCR (KASP) markers. Results of this study constitute an important contribution for the improvement of grain DF in wheat breeding programs.

Electrophile-induced dearomatizing spirocyclization reactions of propargylic cyanamides leading to cyclohexadienone derivatives are described. An unusual one-pot spirocyclization-N-cyanation reaction has been discovered leading directly to the spiro fused derivative. The products obtained through this chemistry may serve as key intermediates in synthetic approaches to several Leucetta alkaloids.

At the International Maize and Wheat Improvement Center (CIMMYT), wheat quality improvement is an important goal of breeding. CIMMYT scientists develop germplasm, which is diverse for quality traits intended for use in the preparation of different wheat-based products. The integration of quality traits is complex due to the high cost of conducting traditional quality tests. One option for tackling this problem is the use of such rapid-small-scale methods as Solvent Retention Capacity (SRC), SDS Sedimentation (SDSS) and Swelling Index of Glutenin (SIG) to predict flour performance. The objectives of this study were to investigate the effect of genotypes, contrasting environmental conditions and their interactions (GxE) on different rapid-small-scale tests, and to identify their suitability for use in prediction of quality traits. A significant GxE effect was observed for all three methodologies. Overall, SIG was found to be the best predictor of gluten strength across different environments. It was also best at determining bread-making quality in some environments, followed by SDSS for bread making. SRC was found to be useful to select for gluten strength, but for extensibility and bread-making more grain data is needed.

Highlights • Each year from 2009 to 2014, 28 newly developed early-maturing high-yielding CIMMYT wheat lines were evaluated across locations in South Asia. • Maximum temperatures in ME5 (continual high temperature stress regions) and minimum temperature in ME1 (terminal high temperature stress regions) had significant impact on grain yield in South Asia. • Significant negative genetic correlations of grain yield with days to heading. • Early maturity has the potential to improve adaptation and maintenance of genetic gains in South Asia., Maintaining wheat productivity under the increasing temperatures in South Asia is a challenge. We focused on developing early maturing wheat lines as an adaptive mechanism in regions suffering from terminal heat stress and those areas that require wheat adapted to shorter cycles under continual high temperature stress. We evaluated the grain yield performance of early-maturing heat-tolerant germplasm developed by CIMMYT, Mexico at diverse locations in South Asia from 2009 to 2014 and estimated the breeding progress for high-yielding and early-maturing heat-tolerant germplasm in South Asia. Each year the trial comprised of 28 new entries, one CIMMYT check (Baj) and a local check variety. Locations were classified by mega environment (ME); ME1 being the temperate irrigated locations with terminal high temperature stress, and ME5 as hot, sub-tropical, irrigated locations. Grain yield (GY), days to heading (DTH) and plant height (PH) were recorded at each location. Effect of temperature on GY was observed in both ME1 and ME5. Across years, mean minimum temperatures in ME1 and mean maximum temperatures in ME5 during grain filling had significant negative association with GY. The ME1 locations were cooler that those in ME5 in the 5 years of evaluations and had a 1–2 t/ha higher GY. A mean reduction of 20 days for DTH and 20 cm in PH was observed in ME5. Negative genetic correlations of −0.43 to −0.79 were observed between GY and DTH in South Asia during 2009–2014. Each year, we identified early-maturing germplasm with higher grain yield than the local checks. A positive trend was observed while estimating the breeding progress across five years for high-yielding early-maturing heat tolerant wheat compared to the local checks in South Asia. The results suggests the potential of the high-yielding early-maturing wheat lines developed at CIMMYT in improving wheat production and maintaining genetic gains in South Asia.

Abiotic stress caused by increasing temperature and drought is a major limiting factor for wheat productivity around the world. Wheat plays an important role in feeding the world, but climate change threatens its future harvest and nutritional quality. In this study, grain iron (Fe) and zinc (Zn) concentrations of 54 wheat varieties, including CIMMYT derived historic and modern wheat varieties grown in six different environmental conditions, were analyzed. The objective of the study was to evaluate the effect of water and heat stress on the nutritional value of wheat grains with a main emphasis on grain protein content, Zn and Fe concentrations. Significant effects of environment on protein content and grain micronutrients concentration were observed. The protein and Zn concentrations increased in the water and heat stressed environments, whereas Zn and Fe yield per unit area was higher in non-stress conditions. The results suggest that genetic gains in the yield potential of CIMMYT derived wheat varieties have tended to reduce grain Zn, in some instances; however, environmental variability might influence the extent to which this effect manifests itself.

Durum wheat accounts for more than 50% of the total wheat-growing area in the Mediterranean region, where is used for the preparation of diverse food products, including pasta and bread. The effects of drought and heat stresses on grain morphology, grain composition (protein, iron and zinc micronutrients), processing and pasta and bread-making quality in durum wheat varieties were analyzed. The results revealed significant differences among the genotypes, as well as unique responses to the environmental stresses. Micronutrients concentration (iron and zinc), processing and pasta-making quality was favored by drought but not by heat stress. Overall, the durum wheat lines showed inferior values for bread volume compared to the bread-wheat checks. However, some durum genotypes in specific environment had almost the same performance. To develop durum wheat cultivars with similar bread-making quality to that of bread wheat, it is necessary to achieve a better balance of tenacity and extensibility. The development of durum lines with good bread-making quality could increase the commercial value of this crop.

Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum, is a serious problem in oilseed rape and mustard worldwide. Locating effective sources of host resistance to this disease offers the best long term prospects for its improved management. For this reason, 19 Brassica napus genotypes from Australia (6), China (7) and India (6) and 34 Brassica juncea genotypes from Australia (6), China (3) and India (25), were screened for resistance to SSR under field conditions using a stem inoculation test. There were significant differences ( P B. napus and B. juncea test genotypes in relation to the stem lesion length. The most resistant B. napus genotypes were Oscar from Australia, Zhongyou-za No. 8, Fan 168 and Ding 110 from China, all with stem lesion lengths ≤4.1 cm. The most susceptible B. napus were GSL2 from India, and 03-p74-11 from China, with stem lesion lengths ≥12 cm. The most resistant B. juncea genotypes were Aravali and Bio-902 from India with stem lesion lengths ≤5.7 cm; while the most susceptible were JM018 from Australia, Xinyou 8 and Xinyou 9 from China, Sanjucta Ascsh and Basanti from India, all with stem lesion lengths >10 cm. In particular, this high level resistance in B. napus Oscar from Australia, Zhongyou-za No. 8, Fan 168 and Ding 110 from China provides sources of resistance for oilseed Brassica breeding programs in Australia; particularly resistance to pathotype 76, the dominant prevailing S. sclerotiorum pathotype. It is noteworthy that progenies from B. napus crosses of Oscar with Ding 110 express isolate-independent host resistance, making Oscar and Ding 110, and potentially their progenies, an ideal target to exploit in developing new commercial rapeseed cultivars that not only have more effective resistance to SSR, but resistance that is effective across multiple pathotypes of this pathogen. These findings ensure successful management of SSR based on host resistance rather than fungicides is now possible providing breeders take the opportunities now presented.

Arabinoxylans (AXs) are the major dietary fiber (DF) component in wheat and their consumption has been associated with several health benefits. Genetic improvement of the AX in refined wheat flour could be a good solution to improve the DF daily consumption while maintaining the flour desirable quality. In this study, 193 common wheat lines were analyzed for their AX content in refined flour and end-use quality. Wide variation in both the total arabinoxylan (TOT-AX) (10.8–16.5 mg/g) and water-extractable arabinoxylan (WE-AX) (3.2–7.6 mg/g) was identified and, in both cases, the genotype had the greatest impact on the observed phenotypes. Variation in the endogenous AX fractions appeared to have a moderate effect on wheat quality. The WE-AX, specifically, were positively correlated with gluten strength (r = 0.11 to 0.32) and bread loaf volume (r = 0.16), whereas the TOT-AX were negatively correlated with dough extensibility (r = −0.11) and bread making quality (r = −0.11). Overall, results of this study show that the genetic improvement of grain AX is feasible and that the AXs present in refined flour do not dramatically alter wheat quality indicating that it is possible to select varieties with high AX endosperm content end desired end-use quality.

Grain yield progress over 50 years of spring wheat breeding at the International Maize and Wheat Improvement Center (CIMMYT) was determined in field trials conducted during five crop seasons (2013–2017) at Norman E. Borlaug research station near Ciudad Obregon, Mexico. The trials included 30 varieties (24 bread wheat and 6 durum wheat) released between 1965–2014 and were sown under managed optimum, drought, and heat stress conditions. The optimum irrigated environment had 3 management systems, flat sowing with weekly drip irrigation (FDI), bed sowing with flood irrigation (BFI), and flat sowing with flood irrigation (FFI). The drought environment had 2 management systems, flat sowing with reduced irrigation (FRI) and flat sowing under severe drought stress (FSD). The heat stress environment was sown in beds (HFI) three months later than the normally sown irrigated and drought environments. The rate of grain yield progress was estimated relative to Sonalika released in 1965 and Mexicali C75 released in 1975 for bread and durum wheat, respectively. Grain yield progress per year for bread wheat was, 31.2 kg ha−1, 35.3 kg ha−1, and 24.7 kg ha−1 in irrigated environments FDI, BFI, and FFI, respectively. In the stress environments, bread wheat grain yield progress was estimated as 25.6 kg ha−1, 17.7 kg ha−1, and 18.1 kg ha−1 per year in FRI, FSD, and HFI, respectively. For durum wheat, the grain yield progress was estimated as 29.6 kg ha−1, 48.1 kg ha−1, 18.8 kg ha−1, and 29.8 kg ha−1, per year in FDI, BFI, FFI, and HFI, respectively. Trait linkage graph analysis using LASSO regularized graphical model estimated that biomass, harvest index, and grains per meter square (GNM) were linked to grain yield progress in all environments. Thousand kernel weight was associated with grain yield progress under optimum and heat stress conditions, whereas grain weight per tiller (GWT) associated with progress under drought. Results also show that the highest yielding varieties in each environment however, had different trait attributes, with some varieties having higher GNM and tillers per meter square compensating for low GWT, while others had high GWT to compensate for reduced GNM. In conclusion, CIMMYT’s wheat breeding program has continued to show progress in grain yield in different environments/management systems, and while certain traits have consistently improved over the years, the varieties developed have employed different trait strategies to achieve final grain yield.

Unpredictable temperatures and rainfall associated with climate change are expected to affect wheat (Triticum aestivum L.) production in various countries. The development of climate-resilient spring wheat cultivars able to maintain grain yield and quality is essential to food security and economic returns. We tested 54 CIMMYT spring bread wheat genotypes, developed and/or released over a span of 50 years, in the field for two years under optimum sowing dates, as well as using two delayed sowing dates to expose crops to medium and severe heat-stress conditions. The grain yield and yield components were severely affected as the heat-stress increased. Two contrasting groups of 10 lines each were identified to determine the effect of heat-stress on bread-making quality. The first set included entries that produced high yields in optimal conditions and maintained higher yields under heat-stress (superior-yielding lines), while the second set included genotypes that did not perform well in the environment with high temperature (inferior-yielding lines). We identified genotypes exhibiting bread-making quality stability, as well as the quality traits that had higher correlation with the loaf volume in the environment without stress and under heat-stress. Of all the quality traits tested, dough extensibility (AlvL) and grain protein content had a significant influence in heat-stress adaptation. Most of the lines from the superior-yielding group were also able to maintain and even improve quality characteristics under heat-stress and therefore, could be used as parents in breeding to develop high-yielding and stable quality wheat varieties.

Highlights • Linear and consistent grain yield genetic gains in the HRWYT has been observed. • Several best performing lines were common in both high and low rainfall environments. • The genetic gains were explained by paralleled increases in grain weight, day to maturity and grain filling period. • These results indicate continuous genetic progress and yield stability in the HRWYT germplasm developed by CIMMYT., The effects of climate change together with the projected future demand represents a huge challenge for wheat production systems worldwide. Wheat breeding can contribute to global food security through the creation of genotypes exhibiting stress tolerance and higher yield potential. The objectives of our study were to (i) estimate the annual grain yield (GY) genetic gain of High Rainfall Wheat Yield Trials (HRWYT) grown from 2007 (15th HRWYT) to 2016 (24th HRWYT) across international environments, and (ii) determine the changes in physiological traits associated with GY genetic improvement. The GY genetic gains were estimated as genetic progress per se (GYP) and in terms of local checks (GYLC). In total, 239 international locations were classified into two groups: high- and low-rainfall environments based on climate variables and trial management practices. In the high-rainfall environment, the annual genetic gains for GYP and GYLC were 3.8 and 1.17 % (160 and 65.1 kg ha−1 yr−1), respectively. In the low-rainfall environment, the genetic gains were 0.93 and 0.73 % (40 and 33.1 kg ha−1 yr−1), for GYP and GYLC respectively. The GY of the lines included in each nursery showed a significant phenotypic correlation between high- and low-rainfall environments in all the examined years and several of the five best performing lines were common in both environments. The GY progress was mainly associated with increased grain weight (R2 = 0.35 p < 0.001), days to maturity (R2 = 0.20, p < 0.001) and grain filling period (R2 = 0.06, p < 0.05). These results indicate continuous GY genetic progress and yield stability in the HRWYT germplasm developed and distributed by CIMMYT.

The development of high-yielding wheat genotypes containing micronutrient-dense grains are the main priorities of biofortification programs. At the International Maize and Wheat Improvement Center, breeders have successfully crossed high zinc progenitors including synthetic hexaploid wheat, T. dicoccum, T. spelta and landraces to generate high-zinc varieties. In this study, we report a genome-wide association using a wheat diversity panel to dissect the genetics controlling zinc, iron, copper, manganese and phosphorus concentrations in the grain and rachis during grain development and at physiological maturity. Significant marker-trait associations (MTAs) were identified for each nutrient using multi-locus mixed model methodologies. For mature grain, markers that showed significant pleiotropic effects were found on chromosomes 1A, 3B and 5B, of which those on chromosome 5B at ∼95.5 cM were consistent over two growing seasons. Co-located MTAs were identified for the nutrient concentrations in developing grain, rachis and mature grain on multiple chromosomes. The identified genomic regions included putative candidate genes involved in metal uptake and transport and storage protein processing. These findings add to our understanding of the genetics of the five important nutrients in wheat grain and provide information on genetic markers for selecting high micronutrient genotypes.

Highlights • A wheat population of 287 diverse spring wheat lines were evaluated in a multilocation trial. • Genome-wide association studies (GWAS) were applied to detect significant marker- straw fodder quality trait associations. • Five genomic regions contributed for six traits (ADF, ADL, ASH, IVOMD, ME and NDF). • ADF and ADL mapped in the common QTL region on chromosome 2B. Similarly, for the IVOMD and ME, QTLs were found on chromosome 5B. • Strong genotypic variations of GY and SY do exist. The lack of any similar variations in straw fodder quality traits is intriguing and requires further research., A wheat association mapping population consisting of 287 diverse spring wheat lines were evaluated for three years in one location (Varanasi) and out of these for one year across three locations (Karnal, Dharwad and Varanasi) in India. Straw fodder quality traits analyzed were nitrogen (N) content, neutral (NDF) and acid (ADF) detergent fiber, acid detergent lignin (ADL), ash (ASH), in vitro organic matter digestibility (IVOMD) and metabolizable energy (ME) content. Grain yield (GY) and straw yield (SY) were also recorded. Highly significant (P

As a major cereal crop worldwide, wheat contributes on average one-fifth of the calories in the human diet and is the main source of protein and nutrients for much of the world's population. Wheat varieties with improved nutritional quality, high grain yield and desirable processing quality attributes in adapted genetic backgrounds can help alleviate nutrient deficiencies among resource poor people. This paper reports advances in targeted crosses of landraces and ancestors of common wheat ( Triticum aestivum L.), such as Aegilops tauschii , Triticum turgidum ssp. diccocoides , T. turgidum ssp. dicoccum and T. aestivum ssp. spelta species, which feature significant genetic variation for grain zinc and iron, with high-yielding bread wheat lines from the CIMMYT breeding program that have desirable processing and end-use quality. High-yielding lines that resulted from these crosses possessed preferred processing quality traits and 10–90% higher grain micronutrient concentrations than popular commercial varieties.

Micronutrient deficiencies, especially those arising from zinc (Zn) and iron (Fe), pose serious human health problems for more than 2 billion people worldwide. Wheat is a major source of dietary energy and protein for the world's growing population, and its potential to assist in reducing micronutrient-related malnutrition can be enhanced via integration of agronomic fertilization practices and delivery of genetically-manipulated, micronutrient rich wheat varieties. Targeted breeding for these biofortified varieties was initiated by exploiting available genetic diversity for Zn and Fe from wild relatives of cultivated wheat and synthetic hexaploid progenitors. The proof-of-concept results from the performance of competitive biofortified wheat lines showed good adaptation in target environments without compromising essential core agronomic traits. Agronomic biofortification through fertilizer approaches could complement the existing breeding approach; for instance, foliar application of Zn fertilizer can increase grain Zn above the breeding target set by nutritionists. This review synthesizes the progress made in genetic and agronomic biofortification strategies for Zn and Fe enrichment of wheat.

We report crater formation due to interaction of the high power laser pulse with the brass and aluminum in water and air ambient. The deposited nanostructures on brass near and away from the crater periphery are distinctly different with larger particle size (∼3.5 μm) and broader particle size distribution with full width half maximum (FWHM) ∼2.9 μm close to the crater compared to relatively smaller particle size (∼2.5 μm) and narrower size distribution (FWHM ∼1.7 μm) near the periphery of the crater in air ambient. The morphology of brass in water ambient shows nanosize particles (∼55 nm) and narrow distribution (FWHM ∼7.5 nm) away from the crater with nanorod shaped structures at crater periphery.

A series of N-substituted (Z)-2-imino-(5Z)-ylidene thiazolidines/thiazolidin-4-ones were synthesized and their antiproliferative activities against colon (HCT-116) and breast (MCF7) cancer cell lines were evaluated utilizing an MTT growth assay. A 2D-QSAR investigation was conducted to probe and validate the obtained antiproliferative properties for the thiazolidine derivatives. The majority of the thiazolidines exhibit higher potency against a colon cancer cell line relative to the standard reference. The p-halophenylimino p-anisylidene derivatives exhibited the highest anti-proliferative activity against HCT116 relative to control (IC50 = 8.9–10.0 μM compared to 20.4 μM observed for 5-fluorouracil as positive control). An X-ray study confirmed the Z, Z′-configurations for two examples of the synthesized compounds.

Time-resolved and space-resolved spectroscopic and imaging studies of colliding carbon plumes are reported, with the aim of understanding the dynamics of the ablated plume in comparison to single-plume carbon plasma. Laser produced colliding plumes and single plume were studied under vacuum (of the order 5 × 10− 5 mbar) in a nitrogen environment using a flat graphite target. Due to the interaction of energetic particles of two colliding plumes, a new particle layer is formed that stagnate for a longer time than the seed plasma. Variation of the plume front and dimension of the stagnation layer with time are also reported.

High temperatures are a primary concern for wheat production in South Asia. A trial was conducted to evaluate the grain yield performance of high yielding, early maturing heat tolerant CIMMYT wheat lines, developed recently in Mexico for adaptation to high temperature stresses in South Asia. The trial, comprised of 28 entries and two checks, was grown in 13 locations across South Asia and two environments in Mexico. Each location was classified by mega environment (ME); ME1 being the temperate irrigated locations with terminal high temperature stress, and ME5 as warm, tropical, irrigated locations. Grain yield (GY), thousand kernel weight (TKW), days to heading (DH) and plant height (PH) were recorded at each location. Canopy temperature (CT) was also measured at some locations. Significant differences were observed between ME for DH, PH, GY, and TKW. The cooler ME1 locations had a mean DH of 83 days, compared to 68 days mean DH in ME5. The ME1 locations had higher mean GY of 5.26 t/ha and TKW of 41.8 g compared to 3.63 t/ha and 37.4 g, respectively, for ME5. Early heading entries (

Genetic biofortification to improve zinc (Zn) and iron (Fe) concentrations in bread wheat ( Triticum aestivum L.) could reduce micronutrient malnutrition-related problems in the developing world. A breeding program on wheat was started to enhance Zn and Fe concentrations and other essential traits needed in a successful commercial variety. The first set of advanced lines derived from crosses of high yielding wheats with genetic resources possessing high Zn and Fe such as Triticum spelta , landraces and synthetic wheat based on Triticum dicoccon were tested at nine locations in South Asia and Mexico for Zn and Fe concentration, grain yield and other traits. Analyses of variance across locations revealed significant genotypic, environmental and genotype × environment (G × E) effects for grain Zn and Fe concentrations and grain yield. Variances associated with environmental effects were larger than the genotypic and G × E effects for all three traits, suggesting that environmental effects have relatively greater influence. Although G × E interaction was significant, high heritabilities were observed for Zn and Fe concentrations at individual sites and across environments, reflecting non-crossover type of interaction. This trend was confirmed by the high genetic correlations between locations that showed similar ranking of entries across locations, indicating that it is possible to select the best adapted entries with high Zn and Fe concentration. Pooled data across locations showed increments of 28% and 25% over the checks for Zn and Fe. A considerable number of entries exceeded intermediate to full breeding target Zn concentrations, indicating that it is possible to develop Zn-biofortified varieties with competitive yields and other farmer preferred agronomic traits. The positive and moderately high correlation between Zn and Fe concentration suggest good prospects of simultaneous improvement for both micronutrients.

A set of 10 bread wheat (Triticum aestivum L.) and six durum wheat (T. turgidum L.) genotypes near-isogenic for either the Rht1 or Rht2 dwarfing genes were analyzed for plant height, kernel weight, coleoptile length and grain yield. Coleoptile length was measured at three different temperatures and plant height, kernel weight and grain yield determined in six different environments. Durum wheat, regardless of stature, produced longer coleoptiles than bread wheat at higher temperature. Within the non-Rht isolines, plant height and coleoptile length were independent characters. The tall durum wheats tended to be taller than their bread wheat counterparts, indicating an absence of minor genes for reduced height. However, a number of bread wheat cultivars showed relatively small height increases following removal of the Rht gene and substantially greater increases in coleoptile length. Coleoptile length was more highly correlated (r2=0.53, P

Aromatic electrophilic substitution reactions such as alkylation, acylation, benzoylation, and sulfonylation were studied in the presence of a catalytic amount of Cu(OTf) 2 and Sn(OTf) 2 . Cu(OTf) 2 was very efficient for alkylation, acylation, and benzoylation reactions. However, in case of sulfonylation reactions, Sn(OTf) 2 gave better results.

Reputational concerns are arguably the single most powerful incentive for board directors to act in the interest of shareholders. We propose a model to investigate the impact of boards’ reputational concerns on the level and structure of executive compensation, the use of camouaged pay, and the relation between board independence and compensation decisions. We show that, in order to be perceived as independent, boards lower managers’ pay, but may also pay managers in hidden ways or structure compensation ineciently. Interestingly, independent boards, not manager-friendly boards, are more likely to make use of hidden compensation. We apply our model to study the costs and benets of greater pay transparency and of measures, such as say-on-pay initiatives, that

Executive compensation serves as a metric by which investors measure the quality of a firm's governance. In this paper, I explore how the signaling role of executive compensation impacts the compensation decisions of boards. I show that reputational concerns often cause boards to adopt pay packages that are inefficient. For example, boards may offer contracts that provide excessive incentives to signal that their firms are well-governed. Moreover, to avoid investor criticism, certain boards opt to transfer rents to executives in opaque and costly ways. Although the model predicts that captured boards compensate their executives more than independent boards, it is not the most captured and entrenched boards that are prone to choose inefficient forms of pay as commonly argued. Rather, it is those boards most responsive to investor pressure that signal their independence in a costly manner.

Investors typically base executive compensation on performance measures reported by managers and verified by third-party monitors. This paper explicitly examines how compensation influences the reporting behavior of managers and auditors and finds that (1) strengthening the link between pay and reported performance can result in a weaker link between pay and actual performance and, consequently, lower managerial effort; (2) conservatism among auditors improves performance measurement; (3) in contrast to auditors, raising penalties on managers for overstating earnings can reduce audit quality and harm investors; and (4) side agreements between auditors and managers bias auditors, but increase their access to information and may improve investor welfare. These results, in turn, have a number of important implications for the reform of corporate governance.