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Pearl millet [Pennisetum glaucum (L.) R. Br.] is a subtropical grain and forage crop. It is privileged with several desirable forage attributes. Nevertheless, research on pearl millet is limited, especially as a forage crop, in developing countries. Therefore, the objectives of this study were to investigate the field performance and stability of pearl millet genotypes for forage yield across seven environments. The study was conducted in seven environments (combination of locations and seasons) during the 2016/2017–2018/2019 seasons. Twenty-five pearl millet genotypes, selected based on forage yield from a core collection of 200 accessions, were arranged in an alpha lattice design with three replications. The parameters measured were fresh forage yield, days to flowering, plant height, number of culms m−2, leaf-to-stem ratio, and stem girth. The combined analysis revealed that environments, genotypes, and their interaction had significant effects on all traits studied except the genotypic effect on stem girth. Across the seven environments, four genotypes (G14, G01, G12, and G22) outyielded the check genotype in fresh matter yield by 20.7, 16.5, 11.0 and 9.8%, respectively. The additive main effects and multiplicative interaction (AMMI) analysis showed that the genotype, environment, and their interaction were highly significant (p ≤ 0.001) for fresh matter yield. The results of AMMI stability values (ASVs) and the genotype selection index (GSI) combined with the AMMI estimate-based selection showed that genotypes G14, G22 and G01 were the most stable and adapted genotypes and were superior to the check genotype. These results indicate that forage pearl millet varieties could be developed directly through evaluating the wealth of available collections or indirectly through hybridization in crop breeding programs.

Developing climate-resilient crop varieties with better performance under variable environments is essential to ensure food security in a changing climate. This process is significantly influenced, among other factors, by genotype × environment (G × E) interactions. With the objective of identifying high-yielding and stable genotypes, 20 elite durum wheat lines were evaluated in 24 environments (location–season combination) during 5 crop seasons (2010/11–2014/15). The REML (residual maximum likelihood)-predicted means of grain yield of 16 genotypes that were common across all environments ranged from 3522 kg/ha in G201 to 4132 kg/ha in G217. Results of additive main effect and multiplicative interaction (AMMI) analysis showed that genotypes (G), environments (E), and genotype × environment interaction (GEI) significantly affected grain yield. From the total sum of squares due to treatments (G + E + GEI), E attributed the highest proportion of the variation (90.0%), followed by GEI (8.7%) and G (1.3%). Based on the first four AMMI selections for grain yield in the 24 environments, genotypes G217, G219, G211, and G213 were selected in 23, 12, 11, and 9 environments, respectively. The genotype and genotype × environment biplot (GGE) biplot polygon view showed that the environments were separated into three mega-environments. The winning genotypes in these mega-environments were G217, G214, and G204. Genotypes G212, G220, G217, G215, and G213 showed low AMMI stability values (ASV), whereas genotypes G217, G220, G212, G211, and G219 showed low genotype selection index (GSI), indicating their better stability and adaptability to the test environments. The results indicated that genotypes G217, G219, G211, G213, and G220 combined both high grain yield and stability/adaptability under dry but irrigated and heat-prone environments. An in-depth analysis of the superior genotypes could help better understand the stress-adaptive traits that could be targeted to further increase durum wheat yield and stability under the changing climate.

The innovation platforms (IP) concept was adopted in Sudan as an effective multi-stakeholders approach for sustainable agricultural R4D. The objectives of this study were to evaluate the IP approach in enhancing wheat production and contributing to food security in Sudan. Six community-based IPs were established in four states. A range of activities were implemented within IPs including technology demonstration, seed production, capacity strengthening, field days, etc. A total of 440 farmer-managed demonstration plots were conducted and yields up to 6.0–8.0 t/ha achieved in some fields. The 4-year average yield across all IPs was 3.8 t/ha compared to the national average of 2.3 t/ha. A total of 2031 (66.6% female) trainees participated in 31 training courses targeted all stakeholders along the value chain. A total of 4335 tons of seeds produced and distributed to seed producers and farmers. More than 2500 tons of seeds produced by farmers diffused to neighbouring farmers. Due to the raised awareness of improved varieties, demand for quality seeds increased. Overall, more than 15,700 (31% female) stakeholders were directly reached. Coupled with enabling production measures, improved technologies encouraged national wheat production and productivity to significantly increase since 2011/2012 by 118,000 ton/year and 0.39 ton/ha/year, respectively. The IP approach was able to engage all stakeholders and brought changes in the attitude of many of them. The IP concept was adopted for technology dissemination and enhancing interaction among stakeholders of a number of crops in Sudan.

The Global Wheat Head Detection (GWHD) dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4700 RGB images acquired from various acquisition platforms and 7 countries/institutions. With an associated competition hosted in Kaggle, GWHD_2020 has successfully attracted attention from both the computer vision and agricultural science communities. From this first experience, a few avenues for improvements have been identified regarding data size, head diversity, and label reliability. To address these issues, the 2020 dataset has been reexamined, relabeled, and complemented by adding 1722 images from 5 additional countries, allowing for 81,553 additional wheat heads. We now release in 2021 a new version of the Global Wheat Head Detection dataset, which is bigger, more diverse, and less noisy than the GWHD_2020 version.

Heat stress is one of the major environmental constraints for wheat production; thus, a comprehensive understanding of the metabolomic responses of wheat is required for breeding heat-tolerant varieties. In this study, the metabolome responses of heat-tolerant genotypes Imam and Norin 61, and susceptible genotype Chinese Spring were comparatively analyzed using Fourier transform infrared (FTIR) spectroscopy in combination with chemometric data mining techniques. Principal component analysis of the FTIR data suggested a spectral feature partially overlapping between the three genotypes. FTIR spectral biomarker assay showed similar heat responses between the genotypes for markers Fm482 and Fm1502, whereas genotype-dependent variations were observed for other markers. The markers Fm1251 and Fm1729 showed contrasting behaviors between heat-tolerant and susceptible genotypes, suggesting that these markers may potentially serve as a tool for distinguishing heat-tolerant genotypes. Linear discriminant analysis (LDA) of the spectra demonstrated a clear separation between the three genotypes in terms of the heat stress effect. Analysis of LDA coefficients identified several spectral regions that were potentially responsible for the discrimination of FTIR spectra between different genotypes and environments. These results suggest that a combination of FTIR and chemometrics can be a useful technique for characterizing the metabolic behavior of diverse wheat genotypes under heat stress.

Drought and high temperature are the major abiotic stresses for wheat production. The present study investigated the effect of drought and chronic heat stress on physiological parameters of durum wheat lines derived from interspecific crosses and their association with yield. Seventy-seven durum wheat lines were evaluated during two seasons (2016–2017 and 2017–2018) for drought tolerance at Tessaout (Morocco) using irrigated and rainfed treatments and for heat tolerance at Wad Medani (Sudan). Five drought screening indices (alone or combined) and physiological parameters were used to assess drought and heat tolerance. Among the physiological parameters used, canopy temperature (CT) had moderate heritability and was significantly affected by both severe and moderate drought stresses. CT at early heading showed a stronger correlation with grain yield (GY) and total biomass (BY) under heat stress. The use of maximum quantum yield of PSII (Fv/Fm) for drought/heat screening was limited by the low genetic variation despite its significant correlation with yield under drought (r2 = 0.22) and heat (r2 = 0.4). The normalized difference vegetation index (NDVI) at vegetative stage was highly correlated with GY and BY and it showed high genotypic variation that can allow for efficient selection. The grain filling rate (GFR) was found to be highly correlated with GY and BY under heat stress. The modified stress tolerance index (MsSTI) had the highest association with GY under drought (R2 = 0.82) while the mean productivity (MP) was adapted to both optimal conditions (R2 = 0.77) and drought stress (R2 = 0.73). The computation of a mean score index (MSI) improved the selection efficiency under drought (R2 = 0.92). The results showed good potential for lines derived from wide crosses to increase variability for heat and drought adaptive physiological traits.

The boom of the 4.0 industrial revolution and the Covid-19 pandemic have changed the teaching and learning process, where digital learning environments have become increasingly necessary and convenient. The application of game-based learning (GBL) provides many benefits, such as helping to improve the quality of the mathematics teaching and learning process. This paper describes digital GBL with the application of Learning Analytics (LA) in a primary school and how the LA approach can enhance learning with GBL. GBL allows students to have more practice in their learning, while LA allows the data on teaching and learning materials to be recorded. The recorded data allows the teachers to systematically analyze them to keep track of students' learning performance. The use of LA is also useful to researchers and game designers. This paper has also proven the importance of the cognitive load theory and its application in GBL. It allows the use of GBL-based application to present learning information to cater to students' cognitive needs. This study involved sixty-four students from a rural primary school who participated in a 10-week GBL-based intervention. The results show that digital GBL helped increase the students' achievement in mathematics. Moreover, the LA process could be used as a mathematics achievement prediction model. In this regard, data on login frequency, duration of use, and the score to predict could be used to predict the intervention's impact on mathematics achievements. The study concludes by discussing the findings and their implications towards GBL and LA-based research and practice in mathematics teaching and learning.

Pearl millet [Pennisetum glaucum (L.) R. Br.] is a subtropical grain and forage crop. It is privileged with several desirable forage attributes. Nevertheless, research on pearl millet is limited, especially as a forage crop, in developing countries. Therefore, the objectives of this study were to investigate the field performance and stability of pearl millet genotypes for forage yield across seven environments. The study was conducted in seven environments (combination of locations and seasons) during the 2016/2017–2018/2019 seasons. Twenty-five pearl millet genotypes, selected based on forage yield from a core collection of 200 accessions, were arranged in an alpha lattice design with three replications. The parameters measured were fresh forage yield, days to flowering, plant height, number of culms m−2, leaf-to-stem ratio, and stem girth. The combined analysis revealed that environments, genotypes, and their interaction had significant effects on all traits studied except the genotypic effect on stem girth. Across the seven environments, four genotypes (G14, G01, G12, and G22) outyielded the check genotype in fresh matter yield by 20.7, 16.5, 11.0 and 9.8%, respectively. The additive main effects and multiplicative interaction (AMMI) analysis showed that the genotype, environment, and their interaction were highly significant (p ≤ 0.001) for fresh matter yield. The results of AMMI stability values (ASVs) and the genotype selection index (GSI) combined with the AMMI estimate-based selection showed that genotypes G14, G22 and G01 were the most stable and adapted genotypes and were superior to the check genotype. These results indicate that forage pearl millet varieties could be developed directly through evaluating the wealth of available collections or indirectly through hybridization in crop breeding programs. [ABSTRACT FROM AUTHOR]

Developing climate-resilient crop varieties with better performance under variable environments is essential to ensure food security in a changing climate. This process is significantly influenced, among other factors, by genotype × environment (G × E) interactions. With the objective of identifying high-yielding and stable genotypes, 20 elite durum wheat lines were evaluated in 24 environments (location–season combination) during 5 crop seasons (2010/11–2014/15). The REML (residual maximum likelihood)-predicted means of grain yield of 16 genotypes that were common across all environments ranged from 3522 kg/ha in G201 to 4132 kg/ha in G217. Results of additive main effect and multiplicative interaction (AMMI) analysis showed that genotypes (G), environments (E), and genotype × environment interaction (GEI) significantly affected grain yield. From the total sum of squares due to treatments (G + E + GEI), E attributed the highest proportion of the variation (90.0%), followed by GEI (8.7%) and G (1.3%). Based on the first four AMMI selections for grain yield in the 24 environments, genotypes G217, G219, G211, and G213 were selected in 23, 12, 11, and 9 environments, respectively. The genotype and genotype × environment biplot (GGE) biplot polygon view showed that the environments were separated into three mega-environments. The winning genotypes in these mega-environments were G217, G214, and G204. Genotypes G212, G220, G217, G215, and G213 showed low AMMI stability values (ASV), whereas genotypes G217, G220, G212, G211, and G219 showed low genotype selection index (GSI), indicating their better stability and adaptability to the test environments. The results indicated that genotypes G217, G219, G211, G213, and G220 combined both high grain yield and stability/adaptability under dry but irrigated and heat-prone environments. An in-depth analysis of the superior genotypes could help better understand the stress-adaptive traits that could be targeted to further increase durum wheat yield and stability under the changing climate. [ABSTRACT FROM AUTHOR]

High temperatures pose a major threat to wheat productivity and necessitate the development of new cultivars that are resilient to future heat stress. Wild emmer (Triticum turgidum L. ssp. dicoccoides), which is a direct progenitor of domesticated durum wheat (Triticum turgidum L. ssp. durum) and contributor to the A and B genome of bread wheat (Triticum aestivum), offers a valuable genetic reservoir for developing climate-resilient wheat. However, the morphology of wild emmer is different from that of durum and bread wheat, in particular, the spikelets are fragile and naturally fall off, making it difficult to study its agronomic traits. In this study, we created nine backcrossed families between the popular durum wheat cultivar ‘Miki 3’ and nine wild emmer accessions collected from northern and southern lineages of this species. The objective was to investigate the intraspecific genetic variation in wild emmer and identify traits associated with heat stress tolerance. We evaluated these nine families under multi-environments ranging from optimum to severe heat stress conditions in Japan and Sudan and measured important agronomic traits. The result showed that two families, developed from accessions of both northern and southern lineages exhibited high harvest index, elevated chlorophyll content, and reduced canopy temperature under heat stress. Additionally, one family developed from an accession of the southern lineage displayed high biomass, harvest index, and seed number under heat-stress conditions. These three families produced high heat tolerant lines with unique introgressed segments from their wild emmer parents on chromosomes 1A, 2B, 5B, 6B, and 7B, which may be linked to heat resilience. From these results, we were able to identify significant intraspecific diversity between the wild emmer accessions in terms of heat stress tolerance. However, no significant tendency between the northern and southern lineages of wild emmer has been identified. These findings emphasize the need to harness not only the interspecific but also the intraspecific genetic variation of wild emmer diversity to uncover valuable genes for heat stress tolerance in wheat breeding programs.

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The boom of the 4.0 industrial revolution and the Covid-19 pandemic have changed the teaching and learning process, where digital learning environments have become increasingly necessary and convenient. The application of game-based learning (GBL) provides many benefits, such as helping to improve the quality of the mathematics teaching and learning process. This paper describes digital GBL with the application of Learning Analytics (LA) in a primary school and how the LA approach can enhance learning with GBL. GBL allows students to have more practice in their learning, while LA allows the data on teaching and learning materials to be recorded. The recorded data allows the teachers to systematically analyze them to keep track of students' learning performance. The use of LA is also useful to researchers and game designers. This paper has also proven the importance of the cognitive load theory and its application in GBL. It allows the use of GBL-based application to present learning information to cater to students' cognitive needs. This study involved sixty-four students from a rural primary school who participated in a 10-week GBL-based intervention. The results show that digital GBL helped increase the students' achievement in mathematics. Moreover, the LA process could be used as a mathematics achievement prediction model. In this regard, data on login frequency, duration of use, and the score to predict could be used to predict the intervention's impact on mathematics achievements. The study concludes by discussing the findings and their implications towards GBL and LA-based research and practice in mathematics teaching and learning. [ABSTRACT FROM AUTHOR]

Heat stress is one of the major environmental constraints for wheat production; thus, a comprehensive understanding of the metabolomic responses of wheat is required for breeding heat-tolerant varieties. In this study, the metabolome responses of heat-tolerant genotypes Imam and Norin 61, and susceptible genotype Chinese Spring were comparatively analyzed using Fourier transform infrared (FTIR) spectroscopy in combination with chemometric data mining techniques. Principal component analysis of the FTIR data suggested a spectral feature partially overlapping between the three genotypes. FTIR spectral biomarker assay showed similar heat responses between the genotypes for markers Fm482 and Fm1502, whereas genotype-dependent variations were observed for other markers. The markers Fm1251 and Fm1729 showed contrasting behaviors between heat-tolerant and susceptible genotypes, suggesting that these markers may potentially serve as a tool for distinguishing heat-tolerant genotypes. Linear discriminant analysis (LDA) of the spectra demonstrated a clear separation between the three genotypes in terms of the heat stress effect. Analysis of LDA coefficients identified several spectral regions that were potentially responsible for the discrimination of FTIR spectra between different genotypes and environments. These results suggest that a combination of FTIR and chemometrics can be a useful technique for characterizing the metabolic behavior of diverse wheat genotypes under heat stress. [ABSTRACT FROM AUTHOR]

Sheep husbandry is considered one of the most important activities in the socio-economic development in the Middle East region, especially in Iraq and Islamic Republic of Iran (IRI). Therefore this study was designed to evaluate the level of ovine pasteurellosis vaccine protective antibody titer and identification of the prevailing serotypes in Iraq (Basrah, Baghdad, Tikrit, Mosul, Erbil). The vaccine was made from pasteurella multosida Bio-type A and the serotypes of Mannheimia haemolytica. This investigation was performed from September 2021 to January 2022, in Iraq. Sheep blood sera samples were obtained from control unvaccinated and vaccinated sheep after 14, 21 and 28 days post vaccination. The results showed that out of 319 sheep blood sera samples which were evaluated using indirect Haemagglutination (IHA) test to detect Mannheimia haemolytica serotypes, the high prevalence (100 %) of M. haemolytica A2 was found in all the five study regions area, while 96.5 % was M. haemolytica A7 and 88.1 % was M. haemolytica A1. The level of antibody titer was measured by specific serum antibody titer of pasteurella multosida Bio-type A. The results revealed that out of 268 vaccinated blood sera samples the overall antibody titer were 12 (3.8 %), 16 (5%) and 17 (5.3 %) for protective antibody titer of 1:160, 1:80 and 1:40 respectively and for antibody titer of 1:20 were 15 (4.7%) and for antibody titer of 1:10 were 17 (5.3 %), whereas the antibody titer in the control group was 4 (7.8 %). The result of this study indicated that the vaccine administered has limited protective power against pasteurella multocida Bio-type A which lead to researchers for further study on identification of specific strain of pasteurella multosida and development of multivalent vaccine including the most prevalent pasteurella serotypes. [ABSTRACT FROM AUTHOR]

Background: Injectable anaesthetic agents, topical creams and aqueous solutions have previously been used to anaesthetise the tympanic membrane for minor ear procedures. Topical creams take 20–30 minutes to work and injectable anaesthetics can cause canal swelling. The effectiveness of lidocaine spray has not previously been investigated in patients undergoing minor ear procedures. Methods: Eighteen participants attending for out-patient grommet insertion or intratympanic steroid injection were prospectively recruited for this study over six months. Post-operatively, they were asked about their perceived level of pain and overall experience. Results: The median level of pain measured on an 11-point visual analogue scale was 2 out of 10. Forty-four per cent reported the overall experience as pleasant, with the remainder selecting slightly unpleasant (66 per cent). All participants stated they would undergo the procedure again. Conclusion: Xylocaine spray is simple to administer, rapid-acting and well tolerated by patients for anaesthesia of the tympanic membrane during minor ear procedures in the out-patient setting. [ABSTRACT FROM AUTHOR]

Materials and alloys usually possess distinct properties. In contrast to conventional materials, employment of bi-metal laminates allows achievement of better performance in various properties, such as light density, high strength, high corrosion and wear resistances. Moreover, considering the agriculture machinery and equipment, there is a growing demand for utilization of advanced materials with improved mechanical properties and durability. Bonding (RB) process is one of the new novel methods for production of bi-metal laminates. The study presented explores the asymmetric roll bonding for the purposes of fabrication of bi-metal Al/Br laminates with thickness reduction ratios 10–30% with mismatch speed ratios of 1 : 1.05, 1 : 1.1 and 1 : 1.15. Furthermore, finite element simulation of roll bonding process was investigated using ABAQUS software. Additionally, to improve the bonding strength, the effect of mismatch speed ratios was investigated. Finally, utilizing the scanning electron microscopy (SEM), the bonding surface morphology of samples was studied.

The productivity of durum wheat [Triticum turgidum subsp. durum (Desf.) van Slageren] is affected by drought and/or high temperatures, challenges to be amplified by climate change. Pre‐breeding using wild relatives can supply useful traits for durum wheat improvement to adapt to major abiotic and biotic stresses. Sixty‐seven lines issued from backcrosses of Cham5 and Haurani durum wheat varieties with accessions of Triticum aegilopoides (Link) Bal. ex Koern., T. dicoccoides Koern. ex Schweinf., T. urartu Thumanian ex Gandilyan, and Aegilops speltoides Tausch were evaluated for drought and heat tolerance. The trials were conducted during two seasons (2016−2017 and 2017–2018) at Tessaout, Morocco, under full irrigation (optimal conditions) and rainfed conditions (drought stressed) and at Wed Medani, Sudan, under full irrigation combined with heat stress. The recurrent parents, along with eight best cultivars and elite breeding lines, were used as checks. Drought reduced the grain yield by 62%. Grain yield and drought tolerance index were used to identify lines to be used by breeding programs to enhance drought and heat tolerance. The derivatives lines 142014 (Cham5*3/T. aegilopoides), 142074 (Cham5*3/T. dicoccoides), and 142015 along with the checks Icarachaz and Gidara 2 ranked among the best under heat stress. Under drought stress, the lines 141972 (Haurani*2/T. urartu) and 141973 (Cham5*2/T. dicoccoides) yielded 196 and 142% of their recurrent parents' yield, respectively. High variation was found for agronomic and phenology traits, with heading time explaining 16% of grain yield under drought, while thousand kernel weight accounted for 18% of the yield under heat. We conclude that gene introgression from wild relatives pays off and can increase wheat resilience to cope with climate change effects. [ABSTRACT FROM AUTHOR]

The innovation platforms (IP) concept was adopted in Sudan as an effective multi-stakeholders approach for sustainable agricultural R4D. The objectives of this study were to evaluate the IP approach in enhancing wheat production and contributing to food security in Sudan. Six community-based IPs were established in four states. A range of activities were implemented within IPs including technology demonstration, seed production, capacity strengthening, field days, etc. A total of 440 farmer-managed demonstration plots were conducted and yields up to 6.0–8.0 t/ha achieved in some fields. The 4-year average yield across all IPs was 3.8 t/ha compared to the national average of 2.3 t/ha. A total of 2031 (66.6% female) trainees participated in 31 training courses targeted all stakeholders along the value chain. A total of 4335 tons of seeds produced and distributed to seed producers and farmers. More than 2500 tons of seeds produced by farmers diffused to neighbouring farmers. Due to the raised awareness of improved varieties, demand for quality seeds increased. Overall, more than 15,700 (31% female) stakeholders were directly reached. Coupled with enabling production measures, improved technologies encouraged national wheat production and productivity to significantly increase since 2011/2012 by 118,000 ton/year and 0.39 ton/ha/year, respectively. The IP approach was able to engage all stakeholders and brought changes in the attitude of many of them. The IP concept was adopted for technology dissemination and enhancing interaction among stakeholders of a number of crops in Sudan. [ABSTRACT FROM AUTHOR]

Due to the low genetic diversity in the current wheat germplasm, gene mining from wild relatives is essential to develop new wheat cultivars that are more resilient to the changing climate. Aegilops tauschii, the D-genome donor of bread wheat, is a great gene source for wheat breeding; however, identifying suitable genes from Ae. tauschii is challenging due to the different morphology and the wide intra-specific variation within the species. In this study, we developed a platform for the systematic evaluation of Ae. tauschii traits in the background of the hexaploid wheat cultivar ‘Norin 61’ and thus for the identification of QTLs and genes. To validate our platform, we analyzed the seed dormancy trait that confers resistance to preharvest sprouting. We used a multiple synthetic derivative (MSD) population containing a genetic diversity of 43 Ae. tauschii accessions representing the full range of the species. Our results showed that only nine accessions in the population provided seed dormancy, and KU-2039 from Afghanistan had the highest level of seed dormancy. Therefore, 166 backcross inbred lines (BILs) were developed by crossing the synthetic wheat derived from KU-2039 with ‘Norin 61’ as the recurrent parent. The QTL mapping revealed one novel QTL, Qsd.alrc.5D, associated with dormancy explaining 41.7% of the phenotypic variation and other five unstable QTLs, two of which have already been reported. The Qsd.alrc.5D, identified for the first time within the natural variation of wheat, would be a valuable contribution to breeding after appropriate validation. The proposed platform that used the MSD population derived from the diverse Ae. tauschii gene pool and recombinant inbred lines proved to be a valuable platform for mining new and important QTLs or alleles, such as the novel seed dormancy QTL identified here. Likewise, such a platform harboring genetic diversity from wheat wild relatives could be a useful source for mining agronomically important traits, especially in the era of climate change and the narrow genetic diversity within the current wheat germplasm.

In the face of climate change, bringing more useful alleles and genes from wild relatives of wheat is crucial to develop climate-resilient varieties. We used two populations of backcrossed recombinant inbred lines (BIL1 and BIL2), developed by crossing and backcrossing two intra-specifically diverse Aegilops tauschii accessions from lineage 1 and lineage 2, respectively, with the common wheat cultivar ‘Norin 61′. This study aimed to identify quantitative trait loci (QTLs) associated with heat stress (HS) tolerance. The two BILs were evaluated under heat stress environments in Sudan for phenology, plant height (PH), grain yield (GY), biomass (BIO), harvest index (HI), and thousand-kernel weight (TKW). Grain yield was significantly correlated with BIO and TKW under HS; therefore, the stress tolerance index (STI) was calculated for these traits as well as for GY. A total of 16 heat-tolerant lines were identified based on GY and STI-GY. The QTL analysis performed using inclusive composite interval mapping identified a total of 40 QTLs in BIL1 and 153 QTLs in BIL2 across all environments. We detected 39 QTLs associated with GY-STI, BIO-STI, and TKW-STI in both populations (14 in BIL1 and 25 in BIL2). The QTLs associated with STI were detected on chromosomes 1A, 3A, 5A, 2B, 4B, and all the D-subgenomes. We found that QTLs were detected only under HS for GY on chromosome 5A, TKW on 3B and 5B, PH on 3B and 4B, and grain filling duration on 2B. The higher number of QTLs identified in BIL2 for heat stress tolerance suggests the importance of assessing the effects of intraspecific variation of Ae. tauschii in wheat breeding as it could modulate the heat stress responses/adaptation. Our study provides useful genetic resources for uncovering heat-tolerant QTLs for wheat improvement for heat stress environments.

A thorough exploration of the micrometeorological aspects influencing canopy temperature in contrasting wheat cultivars can unveil the specific mechanisms of adaptation to heat stress. However, information on wheat microclimates in hot environments for crop improvement is lacking. Here, we used a micrometeorological method to investigate wheat’s response to high temperatures. Field experiments were conducted in the Gezira Scheme, Sudan, to compare two high-yielding heat-tolerant cultivars, Imam and Bohaine, in terms of canopy temperature depression (CTD), air temperature gradient (ATG), and vapor pressure gradient (VPG) from a 2 m height to canopy level. The maximum air temperature at 2 m during the main growing season was 37 °C. Air temperature at canopy level was mostly lower in the Imam field than in the Bohaine field, and it was positively correlated with and higher than radiometric canopy surface temperature. The maximum CTD during the reproductive stage was 4.7–6.5 °C in the Bohaine field and 5.0–7.2 °C in the Imam field. ATG was also larger in the Imam field, attributed to the greater leaf area of the Imam canopy, as presumed from the NDVI difference between fields. ATG was negatively correlated with VPG in both fields, and the relationship was stronger at lower nighttime wind speeds and weaker at higher daytime wind speeds. These results indicate that the micrometeorological approach can be used to compare cultivars in high-temperature environments.

Wheat is highly sensitive to temperature beyond the optimum. To improve wheat adaptation to heat stress, the best option is to exploit the diversity of wild wheat progenitors. This study aimed to identify germplasm and quantitative trait loci associated with heat stress tolerance from wild emmer wheat diversity. We evaluated a diverse set of multiple derivative lines harboring chromosome segments from nine wild emmer wheat parents under four environments: two optimum environments at Tottori, Japan and Dongola, Sudan, one moderate heat stress environment, and one severe heat stress environment at Wad Medani, Sudan. Genome-wide association analysis was conducted with 13,312 SNP markers. Strong marker-trait associations (MTAs) were identified for chlorophyll content at maturity on chromosomes 1A and 5B: these MTAs explained 28.8 and 26.8% of the variation, respectively. A region on chromosome 3A (473.7–638.4 Mbp) contained MTAs controlling grain yield, under optimum and severe heat stress. Under severe heat stress, regions on chromosomes 3A (590.4–713.3 Mbp) controlled grain yield, biomass, days to maturity and thousand kernel weight, and on 3B (744.0–795.2 Mbp) grain yield and biomass. Heat tolerance efficiency (HTE) was controlled by three MTAs, one each on chromosomes 2A, 2B, and 5A under moderate heat stress and one MTA on chromosome 3A under severe heat stress. Some of the MTAs found here were previously reported, but the new ones originated from the wild emmer wheat genomes. The favorable alleles identified from wild emmer wheat were absent or rare in the elite durum wheat germplasm being bred for heat stress tolerance. This study provides potential genetic materials, alleles, MTAs, and quantitative trait loci for enhancing wheat adaptation to heat stress. The derivative lines studied here could be investigated to enhance other stress tolerance such as drought and salinity.

Narrow genetic diversity in the wheat gene pool restricts the improvement of wheat quality traits. Aegilops tauschii possesses valuable genetic diversity that can be used to improve not only biotic and abiotic stresses in arid regions but also wheat yield and quality. Our study, which used 392 multiple synthetic derivatives (MSD) panel developed with Ae. tauschii Coss. introgressions, had three main aims: to explore the genetic diversity of high-molecular-weight glutenin subunits (HMW-GS), to investigate the dough strength and the relationship between protein content and grain yield, and to identify lines with a good flour quality. A wide range of allelic diversity was observed at the Glu-D1 locus, reflecting the impact of the different introgressed portions of Ae. tauschii, and a wide variation was found in dough strength even between lines having the same composition of HMW-GS. We report a negative impact on dough strength of subunit 5t+10t from Ae. tauschii and a relatively positive impact of subunit 2t+12.1t. We identified four MSD lines with significantly enhanced flour quality. Regressing the grain yield of the MSD lines against protein content showed no correlation between the two traits and identified lines with comparable grain yield to the recurrent parent and higher protein content. The identified MSD lines could provide a valuable genetic resource for enhancing the end-use quality of flour without any loss in productivity.

Triggered by the need to develop inter-seasonal, multi-cut cereal forage crops, this study aimed at the exploitation of phenotypic variations among the rich pearl millet (Pennisetum glaucum L.) collections in Sudan for possible utilization in forage-type breeding programmes. A total of 100 pearl millet accessions were used in three field trials grown in rainy, winter and summer seasons (2008–2009) at the Gezira Research Station Farm and the Gezira University Experimental Farm. Wide diversity and highly significant differences in the total dry forage yield, days to harvest, plant height, number of tillers/plant and leaf/stem ratio were found among the accessions. At an 80% morphological similarity level, the 100 accessions of pearl millet were clustered into four main groups. In the rainy and winter seasons, 71 and 56% of the accessions produced forage yield of more than 5 t/ha, respectively. In contrast, 77% of the accessions produced less than 5 t/ha in the summer season. Among the top-ranking 25 accessions, two accessions (HSD 2190 and HSD 2236) were common in dry matter yield in the three seasons, whereas 11 accessions were identified in at least two seasons. The presence of such common accessions in more than one season is encouraging for growing pearl millet as a multi-cut crop for a longer period. These results indicated the possibility of the development of forage-suited varieties of pearl millet directly through further evaluation of those common accessions or indirectly through a crop breeding programme. [ABSTRACT FROM AUTHOR]

In non-traditional, heat-stressed environments, wheat breeding programmes were mainly concerned with the introduction and adaptation of high-yielding, heat-tolerant cultivars regardless of the end-use quality. For the recently developed quality-oriented markets, new cultivars should combine the above-mentioned traits with good grain quality to improve economic feasibility of wheat production in these environments. This study aimed to examine the suitability of the conventional sodium dodecyl sulfate sedimentation (SDSS) test for predicting bread-making quality and to evaluate the effectiveness of a prolonged-swelling SDSS test in improving the predictability of end-use quality under heat stress conditions. Conventional and prolonged-swelling SDSS volumes were measured from whole meal of 15 bread wheat genotypes grown for two seasons under two sowing conditions at Gezira Research Farm, Wad Medani, Sudan. Results of correlations of SDSS volumes with total and insoluble protein contents, mixograph peak height and mixograph descending slope indicated the suitability of the SDSS test in predicting bread-making quality under heat-stress irrigated conditions. However, the absence of significant correlations with some quality attributes, such as mixograph peak time and mixograph curve width, demonstrated the non-exclusiveness of the SDSS test for predicting all bread-making quality attributes. The prolonged-swelling SDSS tests did not improve identification of differences among genotypes over the conventional test despite similarly predicting some quality attributes and showing relatively small increases in the correlation coefficient magnitudes with others. SDSS after 10 min from settlement (SDSS10) showed strong correlations with all other SDSS volumes at various times and with most of quality attributes. This suggested that SDSS10 could be used for evaluation of bread-making quality in early generations of the breeding programme in the hot irrigated conditions of Sudan and similar environments. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) is known to be negatively affected by heat stress, and its production is threatened by global warming, particularly in arid regions. Thus, efforts to better understand the molecular responses of wheat to heat stress are required. In the present study, Fourier transform infrared (FTIR) spectroscopy, coupled with chemometrics, was applied to develop a protocol that monitors chemical changes in common wheat under heat stress. Wheat plants at the three-leaf stage were subjected to heat stress at a 42 °C daily maximum temperature for 3 days, and this led to delayed growth in comparison to that of the control. Measurement of FTIR spectra and their principal component analysis showed partially overlapping features between heat-stressed and control leaves. In contrast, supervised machine learning through linear discriminant analysis (LDA) of the spectra demonstrated clear discrimination of heat-stressed leaves from the controls. Analysis of LDA loading suggested that several wavenumbers in the fingerprinting region (400–1800 cm−1) contributed significantly to their discrimination. Novel spectrum-based biomarkers were developed using these discriminative wavenumbers that enabled the successful diagnosis of heat-stressed leaves. Overall, these observations demonstrate the versatility of FTIR-based chemical fingerprints for use in heat-stress profiling in wheat. [ABSTRACT FROM AUTHOR]

Aegilops tauschii Coss., the D genome donor of hexaploid wheat (Triticum aestivum L.), is the most promising resource used to broaden the genetic diversity of wheat. Taxonomical studies have classified Ae. tauschii into two subspecies, ssp. tauschii and ssp. strangulata. However, molecular analysis revealed three distantly related lineages, TauL1, TauL2 and TauL3. TauL1 and TauL3 includes the only ssp. tauschii, whereas TauL2 includes both subspecies. This study aimed to clarify the phylogeny of Ae. tauschii and to find the traits that can differentiate between TauL1, TauL2 and TauL3, or between ssp. tauschii and ssp. strangulata. We studied the genetic and morpho-physiological diversity in 293 accessions of Ae. tauschii, covering the entire range of the species. A total of 5880 high-quality SNPs derived from DArTseq were used for phylogenetic cluster analyses. As a result, we observed wide morpho-physiological variation in each lineage and subspecies. Despite this variation, no key traits can discriminate lineages or subspecies though some traits were significantly different. Of 124 accessions previously lacking the passport data, 66 were allocated to TauL1, 57 to TauL2, and one to TauL3.

Kernel hardness influences the milling and baking quality of wheat. Stress environments such as heat and combined heat-drought can produce harder kernels, thereby affecting the overall wheat quality. Beside puroindoline genes that are known to determine hardness, other QTLs contribute to the hardness. These QTLs, especially under stress conditions, need extensive research. Moreover, understanding the modification or stabilization of hardness under stress condition and the relationship with stress tolerance will facilitate the selection of superior lines that maintain both high yield and quality even under the stress environment. Therefore, in the current work, we aimed to identify the genetic loci and marker trait associations (MTAs) that contributes for hardness under optimum conditions in Japan, and heat and combined heat-drought (HD) conditions in Sudan. We used a panel of multiple synthetic derivatives (MSD) having diverse Aegilops tauschii genome segments and investigated the association between hardness stabilization and stress tolerance. Under stress conditions, we observed that less reduction of kernel weight is associated with either low change or stable kernel hardness. We identified 47 markers associated with hardness under all conditions; the D genome was the main contributor. For the first time, we found a significant association with hardness under stress conditions on chromosome 4D. We dissected several candidate genes associated with the change of hardness under stress conditions. Our results will improve the understanding of the genetic factors that affect wheat hardness stability.

Drought and high temperature are the major abiotic stresses for wheat production. The present study investigated the effect of drought and chronic heat stress on physiological parameters of durum wheat lines derived from interspecific crosses and their association with yield. Seventy-seven durum wheat lines were evaluated during two seasons (2016–2017 and 2017–2018) for drought tolerance at Tessaout (Morocco) using irrigated and rainfed treatments and for heat tolerance at Wad Medani (Sudan). Five drought screening indices (alone or combined) and physiological parameters were used to assess drought and heat tolerance. Among the physiological parameters used, canopy temperature (CT) had moderate heritability and was significantly affected by both severe and moderate drought stresses. CT at early heading showed a stronger correlation with grain yield (GY) and total biomass (BY) under heat stress. The use of maximum quantum yield of PSII (Fv/Fm) for drought/heat screening was limited by the low genetic variation despite its significant correlation with yield under drought (r2 = 0.22) and heat (r2 = 0.4). The normalized difference vegetation index (NDVI) at vegetative stage was highly correlated with GY and BY and it showed high genotypic variation that can allow for efficient selection. The grain filling rate (GFR) was found to be highly correlated with GY and BY under heat stress. The modified stress tolerance index (MsSTI) had the highest association with GY under drought (R2 = 0.82) while the mean productivity (MP) was adapted to both optimal conditions (R2 = 0.77) and drought stress (R2 = 0.73). The computation of a mean score index (MSI) improved the selection efficiency under drought (R2 = 0.92). The results showed good potential for lines derived from wide crosses to increase variability for heat and drought adaptive physiological traits. [ABSTRACT FROM AUTHOR]

Introduction:Imaging of cholesteatomas can be useful especially in cases of recurrent disease. Computed tomography scans have been recommended before primary surgery, but cholesteatoma tissue looks similar to inflammatory tissue. Diffusion-weighted magnetic resonance imaging is both sensitive and specific in detecting cholesteatoma, which appears as a bright signal on a dark background. Non-echo-planar diffusion-weighted magnetic resonance imaging is superior to routine echo-planar diffusion-weighted magnetic resonance imaging as it minimises susceptibility artefacts; however, the addition of this facility involves expensive magnetic resonance scanner upgrading.Method:To avoid the cost of such upgrading, we modified our echo-planar diffusion-weighted magnetic resonance imaging parameters and then scanned 15 consecutive cases of suspected cholesteatoma or suspected recurrent cholesteatoma.Results:Imaging results correlated well with clinical and/or operative findings.Conclusion:These results indicate that software adjustments can enable echo-planar diffusion-weighted magnetic resonance imaging to detect cholesteatomas reliably, and as effectively as non-echo-planar diffusion-weighted magnetic resonance imaging. This discovery has the potential to facilitate reliable delayed post-operative screening of canal wall up mastoidectomies, avoiding the need for a ‘second look’ procedure. [ABSTRACT FROM PUBLISHER]