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Zymoseptoria tritici is the most economically significant fungal pathogen of wheat in Europe. However, despite the importance of this pathogen, the molecular interactions between pathogen and host during infection are not well understood. Herein, we describe the use of two libraries of cloned Z. tritici effectors that were screened to identify effector candidates with putative pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI)-suppressing activity. The effectors from each library were transiently expressed in Nicotiana benthamiana, and expressing leaves were treated with bacterial or fungal PAMPs to assess the effectors ability to suppress reactive oxygen species (ROS) production. From these screens, numerous effectors were identified with PTI-suppressing activity. In addition, some effectors were able to suppress cell death responses induced by other Z. tritici secreted proteins. We used structural prediction tools to predict the putative structures of all of the Z. tritici effectors and used these predictions to examine whether there was enrichment of specific structural signatures among the PTI-suppressing effectors. From among the libraries, multiple members of the killer protein-like 4 (KP4) and killer protein-like 6 (KP6) effector families were identified as PTI suppressors. This observation is intriguing, as these protein families were previously associated with antimicrobial activity rather than virulence or host manipulation. This data provides mechanistic insight into immune suppression by Z. tritici during infection and suggests that, similar to biotrophic pathogens, this fungus relies on a battery of secreted effectors to suppress host immunity during early phases of colonization.

Mutants lacking functional HYD2 homoeologs showed improved seedling growth, but comparable or increased susceptibility to salt stress in tillering plants, suggesting a developmentally restricted role of HYD2 in salt response. Salinity stress threatens global food security by reducing the yield of staple crops such as wheat (Triticum ssp.). Understanding how wheat responds to salinity stress is crucial for developing climate resilient varieties. In this study, we examined the interplay between carotenoid metabolism and the response to salt (NaCl) stress, a specific form of salinity stress, in tetraploid wheat plants with mutations in carotenoid β-hydroxylase 1 (HYD1) and HYD2. Our investigation encompassed both the vulnerable seedling stage and the more developed tillering stage of wheat plant growth. Mutant combinations lacking functional HYD2 homoeologs, including hyd-A2 hyd-B2, hyd-A1 hyd-A2 hyd-B2, hyd-B1 hyd-A2 hyd-B2, and hyd-A1 hyd-B1 hyd-A2 hyd-B2, had longer first true leaves and slightly enhanced root growth during germination under salt stress compared to the segregate wild-type (control) plants. Interestingly, these mutant seedlings also showed decreased levels of neoxanthin and violaxanthin (xanthophylls derived from β-carotene) and an increase in β-carotene in roots. However, tillering hyd mutant and segregate wild-type plants generally did not differ in their height, tiller count, and biomass production under acute or prolonged salt stress, except for decreases in these parameters observed in the hyd-A1 hyd-B1 hyd-A2 hyd-B2 mutant that indicate its heightened susceptibility to salt stress. Taken together, these findings suggest a significant, yet developmentally restricted role of HYD2 homoeologs in salt-stress response in tetraploid wheat. They also show that hyd-A2 hyd-B2 mutant plants, previously demonstrated for possessing enriched nutritional (β-carotene) content, maintain an unimpaired ability to withstand salt stress.

Summary The development of male gametes, vital to sexual reproduction in crops, requires meiosis followed by successive mitotic cell divisions of haploid cells. The formation of viable pollen is especially vulnerable to abiotic stress, with consequences both for yield and for grain quality. An understanding of key molecular responses when specific stages during pollen development are subjected to stress (e.g. heat) is possible only when sampling is carefully informed by developmental biology. Traditionally, morphological characteristics have been commonly used in cereals as ‘indicators’ of male reproductive stages. We argue that these morphological attributes are strongly influenced by genotype and genotype–environment interactions and cannot be used reliably to define developmental events during microsporogenesis and microgametogenesis. Furthermore, asynchronous development along the axis of a single inflorescence calls for selective sampling of individual florets to define specific reproductive stages accurately. We therefore propose guidelines to standardise the sampling of cells during male reproductive development, particularly when interrogating the impact of stress on susceptible meiosis. Improved knowledge of development will largely negate the variability imposed by genotype, environment and asynchronous development of florets. Highlighting the subtleties required for sampling and investigation of male reproductive stages will make the selection of abiotic stress‐tolerant cereal genotypes more reliable. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTPresent study identified metal accumulation potential, biochemical, growth, and human health risk attributes of wheat varieties (Zincol-16, NARC-09, NARC-11, Pakistan-13, Borlaug-16) cultivated in sewage sludge amended soils, that is, 80% soil + 20% sludge (C), 90% soil + 10% sludge (B) and 100% soil (control, A). Metal accumulation significantly varied (p < 0.05) among wheat varieties and the accretion pattern was roots > straw > grains. The Borlaug-16 was found most efficient for biochemical attributes, that is, proline (0.84), sugar (2.76) and total chlorophyll (2.35) in mg/g amongst selected varieties. Among treatments, maximum mean total chlorophyll (2.18), carotenoids (0.97), sugar (2.88) in mg/g, plant height (76.04 cm), weight per 1000 kernel (55 g) and spike length (4.17 cm) were recorded in B followed by A > C. However, mean membrane stability index%, that is, A (82.76)>B (75.26)>C (54.35) and mean proline contents, that is, C (0.49)>B (0.39)>A (0.29) in mg/g were recorded respectively. Mean hazard quotient and hazard index (HI) calculated on the basis of grain metal contents followed the trend, that is, C > B > A. The HI results revealed highest and lowest health risks associated with the consumption of Zincol-16 and Borlaug-16, respectively. The ‘Borlaug-16’ and ‘sludge treatment B’ are recommended for cultivation and as rate of application, respectively, for ensuring food safety and agro-ecological health.Proline accumulation was a significant and reliable indicator of metal stress in wheat plants. [ABSTRACT FROM AUTHOR]

Introduction: Wheat dwarf virus (WDV), the species Mastrevirus hordei of the genus Mastrevirus in the family Geminiviridae , is a cereal virus commonly detected in several European, African and Asian countries that causes economic losses. Methods: In the spring of 2019, a severe outbreak of wheat dwarfing and yellowing was observed in many winter wheat crops across Serbia. A total of 161 samples were tested for the presence of WDV and other common wheat viruses using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). To obtain the complete genome of 23 selected isolates, several overlapping segments of the WDV genome were amplified and sequenced. A phylogenetic tree was constructed using the whole genome sequences of the WDV isolates identified in this study and 40 selected sequences from GenBank. Results and discussion: The results of DAS-ELISA indicated the presence of WDV in all samples collected from 21 sites in all nine districts surveyed. Further molecular characterization based on complete genome sequencing of 23 selected isolates showed that the Serbian WDV isolates had low nucleotide diversity and were closely related to wheat-infecting isolates from Europe, suggesting the presence of wheat-adapted forms of WDV in Serbia. The constructed phylogenetic tree revealed that Serbian isolates grouped in clade E within the wheat-adapted forms. This study provided the first insight into the genetic structure of WDV in Serbia based on its whole genome sequence. Further studies on the vector biology and population dynamics are needed to better understand the factors influencing the emergence and spread of WDV under local agroecological conditions. [ABSTRACT FROM AUTHOR]

SUMMARY: The domestication process progressively differentiated wild relatives from modern cultivars, thus impacting plant‐associated microorganisms. Endophytic bacterial communities play vital roles in plant growth, development, and health, which contribute to the crop's sustainable development. However, how plant domestication impacts endophytic bacterial communities and relevant root exudates in wheat remains unclear. First, we have observed that the domestication process increased the root endophytic microbial community diversity of wheat while decreasing functional diversity. Second, domestication decreased the endophytic bacterial co‐occurrence network stability, and it did significantly alter the abundances of core microorganisms or potential probiotics. Third, untargeted LC–MS metabolomics revealed that domestication significantly altered the metabolite profiles, and the abundances of various root exudates released were significantly correlated with keystone taxa including the Chryseobacterium, Massilia, and Lechevalieria. Moreover, we found that root exudates, especially L‐tyrosine promote the growth of plant‐beneficial bacteria, such as Chryseobacterium. Additionally, with L‐tyrosine and Chryseobacterium colonized in the roots, the growth of wild wheat's roots was significantly promoted, while no notable effect could be found in the domesticated cultivars. Overall, this study suggested that wild wheat as a key germplasm material, and its native endophytic microbes may serve as a resource for engineering crop microbiomes to improve the morphological and physiological traits of crops in widely distributed poor soils. Significant Statement: Building on previous research, our study further investigates the significant effects of long‐term domestication, which has played a crucial role in the development of human civilization, on the communities of endophytic bacteria and root exudates in wheat. Our findings indicate that wild wheat, along with its naturally occurring endophytic microbes, could be valuable resources for manipulating crop microbiomes and improving the overall characteristics of crops in nutrient‐depleted soils. [ABSTRACT FROM AUTHOR]

Recent research has shown that optimizing photosynthetic and stomatal traits holds promise for improved crop performance. However, standard phenotyping tools such as gas exchange systems have limited throughput. In this work, a novel approach based on a bespoke gas exchange chamber allowing combined measurement of the quantum yield of PSII (F q' /F m'), with an estimation of stomatal conductance via thermal imaging was used to phenotype a range of bread wheat (Triticum aestivum L.) genotypes. Using the dual-imaging methods and traditional approaches, we found broad and significant variation in key traits, including photosynthetic CO2 uptake at saturating light and ambient CO2 concentration (A sat), photosynthetic CO2 uptake at saturating light and elevated CO2 concentration (A max), the maximum velocity of Rubisco for carboxylation (V cmax), time for stomatal opening (K i), and leaf evaporative cooling. Anatomical analysis revealed significant variation in flag leaf adaxial stomatal density. Associations between traits highlighted significant relationships between leaf evaporative cooling, leaf stomatal conductance, and F q' /F m', highlighting the importance of stomatal conductance and stomatal rapidity in maintaining optimal leaf temperature for photosynthesis in wheat. Additionally, g smin and g smax were positively associated, indicating that potential combinations of preferable traits (i.e. inherently high g smax, low K i, and maintained leaf evaporative cooling) are present in wheat. This work highlights the effectiveness of thermal imaging in screening dynamic g s in a panel of wheat genotypes. The wide phenotypic variation observed suggested the presence of exploitable genetic variability in bread wheat for dynamic stomatal conductance traits and photosynthetic capacity for targeted optimization within future breeding programmes. [ABSTRACT FROM AUTHOR]

Wheat is a very vital cereal crop in the development of a nation's economy and agricultural sector. A crucial element that profoundly affects the growth and productivity of wheat is the soil temperature. As an insulating layer, straw mulch controls the soil temperature. Field measurement of the soil temperature is time-consuming and costly; therefore, the present study investigates the applicability of random forest (RF), support vector machine (SVM) and generalized regression neural network (GRNN) models for estimating soil temperature in wheat fields covered with straw mulch using meteorological, soil cover and agronomical parameters. A field study was conducted on the wheat cultivar with two soil cover treatments for measuring the soil temperature at three depths (5, 50 and 80 cm). Soil plant analysis development value; soil cover and depth; daily meteorological data such as average air temperature, average relative humidity, sunshine hours and vapor pressure were used as inputs for machine learning models in training and testing. Statistical performance indicators showed applicability of three models with a root mean square error (RMSE) ranging from 0.245–0.595°C, 0.867–0.886°C and 0.557–0.812°C, Nash-Sutcliffe efficiency (NSE) ranging from 0.917–0.987, 0.823–0.836 and 0.804–0.935 and Lin's concordance correlation coefficient (CCC) ranging from 0.949–0.991, 0.887–0.897 and 0.881–0.957 for the RF, SVM and GRNN, respectively. Results indicated better performance of the RF model for predicting the soil temperature at different depths in the case of both crop and soil cover conditions. Also, the uncertainty analysis indicated the better performance of RF with R-factor and P-factor value of 0.40 and 0.84, respectively. [ABSTRACT FROM AUTHOR]

Safeguarding the agricultural environment from pollution is one of the most critical challenges facing the world in the context of climate change. The loss of nitrogen fertilizers through agricultural runoff or volatilization in the form of nitrate or ammonia emissions is a significant contributor to pollution. This loss also represents an economic waste that may lead to increased prices of agricultural products. Therefore, finding a solution to this problem has become imperative. An experiment was conducted on wheat plants using various rates of urea coated with slow-release materials. The study aimed to assess the impact of these fertilizers on wheat growth and yield, nutrient uptake, and nitrogen utilization efficiency (NUtE). Results demonstrated that urea fertilizers coated with slow-release materials outperformed conventional fertilizers in terms of wheat growth and yield, uptake of nitrogen, phosphorus, and potassium, as well as NUtE. The most favorable outcomes were achieved using urea-formaldehyde, urea-humic, and urea-biochar fertilizers at 100% of the recommended nitrogen application rate. This resulted in economically viable grain production with high fertilizer efficiency. Based on these findings, we recommend applying either urea-formaldehyde or urea-humic at a rate of 107 kg N ha−1 to produce wheat grain and straw with enhanced NUtE. This approach can help reduce environmental pollution caused by nitrogen losses. [ABSTRACT FROM AUTHOR]

Agronomic bio-fortification remains a crucial focus area for enhancing wheat productivity and quality while alleviating environmental pressures. Micronutrient deficiencies, particularly in iron (Fe) and zinc (Zn), persist among the Indian population, especially affecting women. These deficiencies can be effectively addressed through agronomic bio-fortification of wheat grains. To tackle this issue, a comprehensive multilocation (4) field experiment was conducted, incorporating four high-yielding wheat cultivars (HD-3226, HI-1544, DBW-187, and PBW-1-Zn) alongside six foliar fertilizer applications (Control, 2% S, 2% N, 0.5% ZnSO4.7H2O, 1% KCl, and combined treatments) during 2021-22 and 2022-23 utilizing a split-plot design with three replications. Analysis over the years revealed that significant impacts of location and cultivar on yield and its attributes, and Fe, Zn, and protein content of grains. Warmer locations like Hisar exhibited higher yields primarily due to significantly increased earheads/m2 and grains number/m2 compared to other locations. Moreover, Fe content in wheat grains was notably higher in Gurdaspur followed by Hisar, surpassing Ludhiana. Notably, cultivar DBW-187 outperformed others with a 14.75% higher grain yield than the least yielding cultivar, HI-1544. PBW-1-Zn exhibited the highest grain Fe and Zn content among the cultivars studied. The interaction between cultivar and location significantly influenced all yield parameters and grain Fe content. Foliar spray of ZnSO4 (0.5%) during stem elongation and milk stages resulted in significantly higher grain Zn content compared to applications of KCl (1.0%), N (2.0%), and S (2.0%) alone, with an increase of 9.9% over no spray. In conclusion, the selection of appropriate cultivars tailored to specific regions, coupled with strategic agronomic bio-fortification approaches, is imperative for enhancing wheat productivity and grain quality, thereby ensuring nutritional security. [ABSTRACT FROM AUTHOR]

This study investigated the responses of two wheat varieties, Alvand (Zn-inefficient) and Pishtaz (Zn-efficient), to various zinc (Zn) fertilization methods to determine optimal strategies for enhancing wheat growth and grain quality. The primary aim of this research was to evaluate the effects of various Zn fertilization strategies, including foliar applications of Zn sulfate and Zn-EDTA with and without urea, as well as synthetic Zn amino acid complexes, along with soil applications of Zn sulfate, on the yield and nutritional quality of grains in these two contrasting wheat varieties. The results revealed that wheat varieties responded differently to Zn treatments. While Alvand showed a promising trend of elevated grain yield with foliar zinc sulfate application, Pishtaz exhibited a stronger response to foliar treatments like Zn-Met and Zn-EDTA + urea. Yield components as 1000-grain weight and spike weight, were significantly influenced by Zn fertilization. Foliar application of zinc sulfate + urea enhanced 1000-grain weight in Alvand, whereas Zn-EDTA + urea substantially increased spike weight in Pishtaz. Soil application of zinc sulfate was found to be as an effective method to enhance grain Zn content. Furthermore, the Zn concentrations in flour, straw, bran, and roots elucidated the complex patterns of Zn distribution among various plant tissues. Soil applications were particularly effective in increasing Zn levels in flour and bran, while foliar treatments influenced Zn content in straw and roots. Overall, this research highlights the importance of Zn fertilization strategies for different wheat varieties biofortification. These findings can provide practical implications for sustainable wheat production, addressing Zn deficiency challenges, and advancing food security worldwide. Further exploration into the underlying mechanisms of these responses is encouraged to refine Zn management practices for wheat cultivation. [ABSTRACT FROM AUTHOR]

Increasing the yield potential of cultivars can contribute to solving the problems of climate change and the increase in world population. The objectives of this study were to study the variation of 60 wheat (Triticum aestivum L.) genotypes and to estimate the genetic progress in agronomic characters of varieties released in Mexico in the period from 1966 to 2015. The hypothesis was that the increases in yield of the genotypes are the result of the increase in the number of grains per surface unit and biomass. The study was established in six experimental stations of the National Institute of Agricultural Forestry and Livestock Research in the states of Guanajuato, Sonora, Chihuahua, Jalisco, Sinaloa, and Baja California, Mexico. Phenology, yield, and its components were measured. The treatment design was alpha lattice with two replications. The location and genotype that showed the highest yield (P ≤ 0.01) were Baja California and COLIBRI/MONARCA, with 7309 and 5966 kg·ha−1. The average genetic gain in yield was 23.8 kg·ha−1·year−1. The grain weight increase rate was 0.21 g per year. During the period, there was no genetic progress in plant height, heading days, harvest index, grains per square meter, and ears per square meter. The increases in yield of the recent lines are due to increases in ears per square meter, grains per square meter, and biomass. [ABSTRACT FROM AUTHOR]

Triticale combines the yield and quality of wheat with the disease resistance of rye. To choose stable and reasonably high‐yielding varieties and to estimate the degree of variation and environmental interactions, five triticale varieties and one local check were assessed at Dita, Chencha, Bonke, and Kamba localities during 2020 and 2021 in Gamo, South Ethiopia. Analysis of variance (ANOVA), the additive main effect and multiplicative interaction (AMMI) model, and interaction principal component analysis (IPCA1 and IPCA2) indicated significant (p ≤ 0.01) differences between habitats, varieties, and their interactions. The contributions of IPCAs 1 and 2 to the overall variety by environment interaction were substantial (p ≤ 0.01) and accounted for 67.3% and 18.1%, respectively. The average grain yield of the varieties Sinan (4085 kg·ha−1) and Dersolign (4081 kg·ha−1) performed better than those of the other varieties without significantly varying, and Minet (3614 kg·ha−1) was next. The Models demonstrated that Dersolign and Minet were stable and recommended for production in a variety of environments with IPCA values close to zero, low (GSI), low AMMI stability value, and high mean grain yield throughout the environments. Dersolign and Minet are hence for broad production due to their high inflexibility. [ABSTRACT FROM AUTHOR]

Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici (Bgt), is a foliar disease of wheat (Triticum aestivum) that adversely affects both grain yield and quality. Growing resistant cultivars offers an effective and environmentally sustainable solution to managing PM. However, relying on the same genetic source of resistance can lead to resistance breakdown as Bgt isolates rapidly evolve. To mitigate this, identifying novel resistance sources is crucial. In this study, 225 diverse wheat genotypes were evaluated at adult plant stage in disease nurseries over the three crop seasons (2018/2019, 2019/2020 and 2020/2021). Using disease and genotyping data from 12,160 single‐nucleotide polymorphism (SNP) markers, a genome‐wide association study (GWAS) was conducted to identify novel resistance loci. We identified 22 marker loci significantly (at p < 0.005) associated with PM resistance, distributed across 14 wheat chromosomes (1A, 1B, 1D, 2A, 2B, 2D, 3A, 3B, 4A, 4B, 5D, 6A, 7A and 7B). Of these, seven loci overlap with previously identified regions, while the remaining 15 loci represent novel regions reported for the first time in this study. The identified SNP markers have significant potential for wheat breeding programmes, as they can accelerate the development of PM‐resistant cultivars through marker‐assisted selection. [ABSTRACT FROM AUTHOR]

ABSTRACT Check varieties are used in plant breeding and variety testing for a number of reasons. One important use of checks is to provide connectivity between years, which facilitates comparison among genotypes of interest that are tested in different years. When long‐term data are available, such comparisons allow an assessment of realized genetic gain (RGG). Here, we consider the question of how many check varieties are needed per cycle for a reliable assessment of RGG. We propose an approach that makes use of variance component estimates for relevant random effects in a linear mixed model and plugs them into an analysis of dummy datasets set up to represent the design options being considered. Our results show that it is useful to employ a larger number of checks and to keep the replacement rate low. Furthermore, there is intercycle information to be recovered, especially when there are few checks and replacement rates are high, so modelling the cycle main effect as random pays off. [ABSTRACT FROM AUTHOR]

AbstractPurposeMaterials and methodsResultsConclusionKernel texture plays a principal role in determining technological flour properties and end-use quality of wheat products. Hence, a multi-year mutation induction programme was conducted to isolate advanced wheat mutant lines with agro-morphologically superior performance, higher disease resistance and harder grain texture.Radiation mutagenesis was employed in soft textured wheat variety HPW 89 using gamma rays dose of 250, 300 and 350 Gy (Co60: BARC, Mumbai) and evaluated across M1–5 generations. Promising superior mutants selected were evaluated during M4 and M5 generation for induced variability and trait association for agro-morphological and quality traits. The screened mutants were also determined for induced changes at genetic level using gene specific markers for puroindoline genes.A total of 293 agro-morphologically superior mutants isolated showed significant genetic variation in the M4 generation. Single kernel characterization system categorized 267 mutants (8.79–50.06) with higher grain hardness than the HPW 89 variety (7.39). Among these, 108 mutants were selected for agro-morphological and molecular characterization. Significant variations were found in these mutants in either pina and pinb or both puroindoline genes. Clustering among these mutants led to the formation of five clusters and a total of eleven mutants were found with better set of agro-morphological, disease resistance and quality traits.These mutants can serve as important genetic resource for developing harder texture bread wheat varieties in the future grain quality improvement programmes. These mutants will also bridge the need of bakers and millers’ requirement of varieties with specific texture and quality. [ABSTRACT FROM AUTHOR]

The article discusses the enhancement of salt tolerance in wheat through the overexpression of the TaDSU gene, which encodes a SUMO protease. The study shows that TaDSU overexpression leads to increased growth and yield in wheat under saline soil conditions by reducing Na+ content, increasing K+ levels, and enhancing metabolic markers of salt tolerance. The research also highlights the role of the TaDSU gene in deSUMOylating the transcription factor TaMYC2, which contributes to salt tolerance in wheat and Arabidopsis. The study suggests a conserved mechanism of salt tolerance mediated by TaDSU through MYC2 deSUMOylation, providing insights for genetic strategies to improve wheat under saline conditions. [Extracted from the article]

Given the challenges posed by climate change and population growth, Iraq faces increasing demands for food production and water resources. To enhance agricultural productivity and optimize water management for crop efficiency, this study evaluated various wheat varieties, specifically Mawaddah, Bohuth 10, Aba99, and Babel113, under different irrigation level. These level were based on depletion levels of available water at 40%, 55%, and 70%. Key metrics measured included actual evapotranspiration, water use efficiency (WUE), grain yield, spike number, grains per spike, and the weight of 100 grains over the growing seasons of 2022–2023 and 2023–2024. The findings revealed that water consumption varied with depletion levels for all wheat varieties, amounting to 435.53, 397.13, and 365.13 mm season-1, and 465.7, 422.10, and 385.40 mm season-1 for the respective depletion levels of 40%, 55%, and 70%, across the two seasons. WUE ranged from 1.01 for Babel 113 at the 70% depletion level to 1.85 for Bohuth and Mawaddah at the 40% depletion level. Among the plant traits, Mawaddah had the best performance at the 40% depletion level, while Babel113 had the lowest performance at the 75% depletion level. The drought sensitivity index varied among the varieties due to their genetic differences. Our research supports the feasibility of utilizing water at depletion levels up to 75% when cultivating drought-tolerant wheat varieties in semi-arid and arid conditions. [ABSTRACT FROM AUTHOR]

Arsenic (As) threatens plant growth and human health because its harmful effects are intensified by its persistent presence in the ecosystem. The absorption of As from the contaminated soil leads to accumulation in grains of food crops posing a serious threat to human health. High concentration of As hindered essential physio-biochemical processes of plants that ultimately diminish the growth and yield of crops. Therefore; a pot study was designed to assess synergistic effect of silicon (Si) and salicylic acid (SA) (control-Ck, 4.0 mM Si, 150 µM SA, 4.0 mM Si + 150 µM SA) in mitigating the adversities of As stress in wheat seedlings exposed to As stress (0, and 100 μM). Wheat seedlings exposed to As showed a significant decline in morphological attributes as well as photosynthetic pigments (chlorophyll a, b and carotenoids). However; foliar application of Si and SA considerably increased morphological parameters and leaf photosynthetic pigments under As stress. The imposition of As resulted in enhance accumulation of hydrogen peroxide, MDA, and electrolyte leakage, increased activities of enzymatic antioxidants (superoxide dismutase, peroxidase, and ascorbate peroxidase and catalase) and an elevated accumulation of essential organic osmolytes (free proline, soluble protein, total soluble sugar, total phenolics) in leaves of wheat seedlings. Furthermore, the application of Si + SA resulted in a remarkable increase in the activities of enzymatic antioxidants and accumulation of organic osmolytes. Simultaneously, it reduced the concentration of hydrogen peroxide, MDA, and electrolyte leakage in As-stress wheat seedlings. Under As-stress, sole and combined application of Si and SA caused a significant reduction in arsenic concentration while enhance Si contents in root and shoot of wheat seedlings. In conclusion, synergistic interaction between Si and SA could alleviate the negative impact of As by enhancing the antioxidant defense system, photosynthetic pigments, facilitating osmotic adjustment, and reducing the lipid peroxidation in maize seedlings. The current findings suggest that the combined exogenous application of Si and SA represent a promising approach for promoting the successful cultivation of wheat in As contaminated soil. [ABSTRACT FROM AUTHOR]

An examination of the dynamics of seed markets in Bihar, India, reveals a paradox—despite an influx of wheat varieties bred by public and private sectors and the proliferation of seed market networks in rural villages, older wheat varieties remain prevalent—necessitating a thorough investigation of the seed distribution system. Unlike most empirical studies that examine the adoption of new and improved crop varieties from a farmer's perspective, our study shifts the focus to the seed supply side. We analyse data collected from 200 private seed dealers who cater to the needs of over 163,000 farmers spread across 10 districts in Bihar. We use descriptive statistics alongside dealer-level and varietal-level regression models to examine the relationship between seed sales and varietal age. Findings indicate that the number of varieties available with a dealer (varietal richness) is positively associated with the number of seed buyers (dealer's reach) and the total quantity of seeds sold. Private varieties are in demand despite their higher prices. Dealer-level models showed that varietal age affects neither the reach nor the sales, allowing older public-sector varieties to coexist with more recent private-sector ones. However, the varietal-level regression models show that dealers rank the new varieties higher as the ones being sold more. To explore the potential of private seed markets to reduce the proliferation of old wheat varieties that are more susceptible to evolving biotic and abiotic stress factors, we recommend strengthening the varietal registration and seed certification processes, implementing better seed traceability systems, and fostering public–private partnerships in variety development and seed dissemination. Investing in market experiments to incentivize seed dealers to engage in quality assurance can help refine strategies and ensure efficient and inclusive dissemination of promising wheat varieties. [ABSTRACT FROM AUTHOR]

Evaluation of genetic biodiversity for micronutrients is crucial for breeding high-quality crops and addressing the negative impacts of mineral deficiencies. The objectives of this research were to assess genetic variation and the relationship between grain Fe and Zn levels and agronomic traits in a diverse collection of wheat varieties. Additionally, the study aimed to determine the correlation between microsatellite markers (SSR) and micronutrient quantities. A total of 42 genotypes (Iranian commercial cultivars, landraces, and Afghan and Swiss varieties) were evaluated over a two-year period. Fe and Zn levels were measured using two semi quantitative staining assays and atomic absorption spectrophotometry (AAS) facility. Semi-quantitative staining methods and AAS showed high correlations for micronutrient contents. Landraces exhibited higher Fe (63.79 mg/kg) and Zn (44.76 mg/kg) but lower grain yield compared with commercial cultivars. Heritability estimates ranged 53%-79.43%, suggesting that genetic variance played a higher contribution in the phenotypic variation of traits than environmental factors. Notably, Fe content displayed significant correlations with days to maturity. Canonical correlation analysis (CCA) revealed that Zn content was correlated with four agronomic traits. Evaluation of genetic diversity using SSR markers demonstrated high genetic variation among the genotypes tested. The analysis of polymorphism information content (PIC) indicated that SSR primers had an average PIC of 0.75, with the Xgwm192 primer exhibiting higher PIC than others. Several SSR markers revealed association with micronutrient content that can be used in marker-assisted selection (MAS) programs aimed at selection of high micronutrient genotypes. In conclusion, the findings underscored the substantial genetic diversity present in micronutrient levels among global wheat genotypes, the potential of landraces for micronutrients biofortification of wheat cultivars through cross hybridization, the utility of staining methods for screening high/low micronutrient genotypes, and use of microsatellite markers for marker-assisted breeding aiming to micronutrient improvement in breeding programs. [ABSTRACT FROM AUTHOR]

ABSTRACT Wheat is a key cereal crop that is substantial to global food security. Fertilizers are crucial in wheat production and significantly impact the yield. This review aims to evaluate the effectiveness of inorganic, organic, and integrated fertilizers in terms of sustainable wheat production and economic and environmental benefits. For this review, we thoroughly examined 133 previous research findings. The results indicate that inorganic fertilizers play a vital role in improving wheat yield. However, continuous use of inorganic fertilizers pollutes the environment, affects beneficial microorganisms in the soil, and increases the emissions of greenhouse gases, consequently decreasing crop yield. Organic fertilizers enhance soil quality, which is critical for crop growth and development. However, a high concentration of methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) are emitted from organic fertilizers, but the CO2 emission rate is less than the sequestration rate. Integrated fertilizers trade off the drawbacks of both inorganic and organic fertilizers. Integrated fertilizers decrease nitrous oxide (N2O) and ammonia (NH3) emissions and carbon loss by 11%–24%, 13%–27%, and 18%, respectively, compared to the sole use of fertilizers. From the review analysis, the highest grain yield (4855 kg ha−1) and net benefit ($2836.66) are achieved by using a combination of 75% organic and 25% inorganic fertilizers at a rate of 120 kg N ha−1. Therefore, this combination is recommended for the users. Furthermore, a site‐specific approach research is needed on integrated fertilizers that simultaneously focus on economic and environmental profits. Also, there must be a policy that supports the farmers in teaching, training, and subsidizing them to adopt integrated fertilizers for sustainable wheat production and improving food security. [ABSTRACT FROM AUTHOR]

ABSTRACT Grain hardness (GH) plays an important role in wheat quality evaluation. Identification of new genes or quantitative trait loci (QTL) for GH is an effective strategy for wheat quality breeding. Here, we used a recombinant inbred line (RIL) population derived from a cross between two hard wheat Yangmai 4 (YM4) and Yanzhan 1 (YZ1) to identify QTL for GH. No QTL was detected on 5D chromosome, as parents YM4 and YZ1 possessed the two hard alleles Pinb‐D1b and Pinb‐D1p at the Hardness‐5D (Ha‐5D) locus, respectively. A total of three GH QTL were identified, among which QGh.yaas‐4B and QGh.yaas‐7D could be detected in all experiments and for mean value, explaining 8.69%–15.07% of the phenotypic variances. QGh.yaas‐4D, co‐located with Rht‐D1, was detected in one experiment and for mean value, explaining 9.94%–11.39% of the phenotypic variances. We were not able to precisely validate QGh.yaas‐4B due to its large mapping interval. Kompetitive allele‐specific PCR (KASP) markers for QGh.yaas‐7D were successfully developed, and then QGh.yaas‐4D and QGh.yaas‐7D were validated in a panel of 101 wheat cultivars/lines (all carrying Pina‐D1a and Pinb‐D1a alleles). Cultivars/lines harbouring the positive alleles of QGh.yaas‐4D and QGh.yaas‐7D increased GH by 85.16% relative to the ones without any positive allele. These results provide new loci and resources in molecular breeding for wheat hardness. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Amylose has a major influence over starch properties and end‐use quality in wheat. The granule‐bound starch synthase I, encoded by Wx‐1, is the single enzyme responsible for amylose synthesis. Natural null mutants of Wx‐1 appear at extremely low frequencies, particularly in the Wx‐D1 locus, where only four spontaneous null variants have been identified, with different geographic origins. The current study identified an induced Wx‐D1 null mutant (M4‐9484) from the M4 generation of an ethyl methanesulfonate‐mutagenized population of wheat cv. ‘SM126’.The sequencing showed that the complete Wx‐D1 ORF sequences of ‘SM126’ and M4‐9484 were 2862 bp long and that there was one SNP mutation between them. The mutation was located at the RNA splice site within the junction of exon 8 and intron 8, which led to abnormal transcription of Wx‐D1, with five different aberrant transcripts being identified in the mutant. The Wx‐D1 null allele resulted in amylose and total starch content being decreased in M4‐9484 in comparison with the wild‐type ‘SM126’, with higher swelling capacity and being fully pasted at higher temperatures than the wild‐type parent.The mutation of the Wx‐D1 null gene affects the formation of amylose directly, resulting in significantly altered starch properties. This discovery offers valuable insights for enhancing wheat starch quality and contributes to the diversification of starch characteristics. It also deepens our understanding of the genetic and molecular mechanisms underlying amylose synthesis, thereby supporting breeding programs. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACT Septoria nodorum blotch (SNB) is a fungal disease of wheat caused by the necrotrophic fungus Parastagonospora nodorum (Berk.), considered as one of the most devastating fungal diseases affecting winter wheat (Triticum aestivum L.). The complex inheritance of resistance to SNB poses significant challenges to breeding programmes. Improving selection precision and identifying novel resistance QTLs are crucial for enhancing SNB resistance. This study investigated strategies for crop genetic improvement, including genome‐wide association mapping (GWAS) and genomic prediction (GP), within a practical breeding programme. A population of 1500 winter wheat breeding lines was phenotyped for SNB resistance over 5 years across 19 geographical locations under natural infection conditions. Despite highly unbalanced breeder's data, medium to high heritabilities for SNB resistance were achieved. GWAS identified 11 significant marker‐trait associations for SNB resistance across Chromosomes 2A, 2B, 4B, 4D, 5D and 7B. GP fivefold cross‐validation analysis revealed a predictive ability of 0.52 for SNB resistance. The resistant wheat genotypes and SNP markers identified in this study will be valuable assets for future breeding efforts to enhance SNB resistance in wheat. [ABSTRACT FROM AUTHOR]

ABSTRACT Machine learning methods were shown to improve the prediction accuracies of genomic prediction of resistance scores compared to methods like RR‐BLUP, which were originally designed for metric rather than ordinal response values. We conducted a cross‐validation study with 361 wheat genotypes evaluated for five fungal diseases. Our objective was to compare the prediction accuracy and the ability to identify the most resistant genotypes of 19 genomic prediction approaches. Each approach consisted of a different combination of prediction method (RR‐BLUP, an alternative method with heterogeneous marker variances, Bayesian generalized linear regression with an ordinal response, support vector machine, gradient boosting machine and random forest), predictor (single SNP markers, LD‐based haplotype blocks, 250 variables generated with an autoencoder and SNPs identified with incremental feature selection) and response value (untransformed and logit‐transformed resistance scores). In our dataset, RR‐BLUP was consistently among the methods with the largest prediction accuracies and the best abilities to identify resistant genotypes in four of five investigated traits. However, in P. triticina, using gradient boosting machine and random forest instead of RR‐BLUP increased the prediction accuracy from 0.64 to 0.71, indicating that machine learning methods may have an advantage over linear models in genomic prediction. We also found that even though there was a positive correlation between the prediction accuracy and Cohen's κ$$ \kappa $$, a measure to judge how well the most resistant genotypes can be identified, the correlation is not perfect and a large value for the prediction accuracy does not necessarily translate into an equally large κ$$ \kappa $$ value. [ABSTRACT FROM AUTHOR]

Wheat yellow (stripe) rust, caused by the fungus Puccinia striiformis f.sp. tritici (Pst), is a devastating disease of wheat worldwide. The success of Pst is largely due to the pathogens ability to rapidly overcome host resistance, generating new races that are easily dispersed between territories through wind-borne transmission of Pst urediniospores. Thus, first signs of entry of new Pst races into a region is usually captured by changes in disease severity. To examine any alterations of winter wheat variety response to Pst infection in Serbia, we analyzed yield and Pst disease severity in field trials conducted in 2014, 2021, and 2023. We specifically focused on analyzing Pst disease severity at growth stages related to yield. Associations between qualitative variables (variety, year) and quantitative variables (yield in untreated plots, yield loss, and disease index (DI) of Pst infection) were analyzed using Principal Component Analysis with mixed data. A General Linear Model was used to investigate the most influential factors on yield, yield loss, and Pst infection. The results indicated that yellow rust disease severity increased over the past decade, suggesting a potential recent change in the Pst population in Serbia. Comparative population genetic analysis of Pst samples from the 2023 wheat season and those collected in Serbia in 2014 confirmed a potential change in the Pst population. In addition, we found that yield losses across wheat varieties varied independently of Pst infection levels, indicating that wheat varieties differ in their ability to overcome damage caused by high levels of Pst infection. Given that the level of pathogen pressure triggering susceptibility reactions is cultivar-specific, our study highlights the need for a deeper focus on the mechanisms underlying these differences. Expanding our understanding of the interactions between pathogens, plant defense responses, and the ability of cultivars to mitigate yield losses will better equip us to predict and prevent potential yield losses in commercial wheat varieties due to yellow rust in the future. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is a devastating disease of wheat, causing yield losses, reduced grain quality, and mycotoxin contamination. Breeding can mitigate the severity of FHB epidemics, especially with genomics-assisted methods. The mechanisms underlying resistance to FHB in wheat have been extensively studied, including phenological traits and genome-wide markers associated with FHB severity. Here, we aimed to improve genomic prediction for FHB resistance across breeding programs by incorporating FHB-correlated traits and FHB-associated loci as model covariates. We combined phenotypic data on FHB severity, anthesis date, and plant height with genome-wide marker data from five Central European winter wheat breeding programs for genome-wide association studies (GWAS) and genomic prediction. Within all populations, FHB was correlated with anthesis date and/or plant height, and a marker linked to the semi-dwarfing locus Rht-D1 was detected with GWAS for FHB. Including the Rht-D1 marker, anthesis date, and/or plant height as covariates in genomic prediction modeling improved prediction accuracy not only within populations but also in cross-population scenarios. [ABSTRACT FROM AUTHOR]

Subsampling a reduced number of accessions from ex situ genebank collections, known as core collections, is a widely applied method for the investigation of stored genetic diversity and for an exploitation by breeding and research. Optimizing core collections for genome-wide association studies could potentially maximize opportunities to discover relevant and rare variation. In the present study, eight strategies to sample core collections were implemented separately for two traits, namely susceptibility to yellow rust and stem lodging, on about 6,300 accessions of winter wheat (Triticum aestivum L.). Each strategy maximized different parameters or emphasized another aspect of the collection; the strategies relied on genomic data, phenotypic data or a combination thereof. The resulting trait-customized core collections of eight different sizes, covering the range between 100 and 800 accession samples, were analyzed based on characteristics such as population stratification, number of duplicate genotypes and genetic diversity. Furthermore, the statistical power for an association study was investigated as a key criterion for comparisons. While sampling extreme phenotypes boosts the power especially for smaller core collections of up to 500 accession samples, maximization of genetic diversity within the core collection minimizes population stratification and avoids the accumulation of less informative duplicate genotypes when increasing the size of a core collection. Advantages and limitations of different strategies to create trait-customized core collections are discussed for different scenarios of the availability of resources and data. [ABSTRACT FROM AUTHOR]

Many soils face dual challenges of cadmium (Cd) contamination and salinization. However, the response of crops, especially wheat, to combined Cd and salinity stress is not understood. Here, wheat was grown in a hydroponic model for 14 days under single and combined Cd and NaCl stresses. Growth parameters, tissue Cd2+ and Na+ contents, and leaf chlorophyll (Chl), O2•−, and MDA levels were determined. Comparative transcriptomic and metabolomic analyses of the leaves were performed. The results showed that combined stress had a greater inhibitory effect on Chl contents and generated more O2•− and MDA, resulting in more severe wheat growth retardation than those under Cd or NaCl stress. Stress-induced decrease in Chl levels may be attributed to the inhibition of Chl biosynthesis, activation of Chl degradation, or a decline in glutamate content. Cd addition weakened the promotional effect of NaCl on SOS1 gene expression, thereby increasing the Na+ content. Contrastingly, NaCl supplementation downregulated the Nramp and ZIP gene expressions related to Cd uptake and transport, thereby impeding Cd2+ accumulation. All stresses enhanced tryptophan content via promoting tryptophan biosynthesis. Meanwhile, Cd and NaCl stresses activated phenylpropanoid biosynthesis and purine metabolism, respectively, thereby increasing the levels of caffeic acid, fumaric acid, and uric acid. Activating the TCA cycle was important in the wheat's response to combined stress. Additionally, NaCl and combined stresses affected starch and sucrose metabolism, resulting in sucrose and trehalose accumulation. Our findings provide a comprehensive understanding of the response of wheat to the combined Cd and salinity stress. [ABSTRACT FROM AUTHOR]

Wheat is one of the most important food crop cultivated across the globe which ensures sustainability and food security to massive world's population, but its production is threatened by both biotic factors like rust (caused by Puccinia species) and abiotic stresses such as salinity. In this study, 41 salt-tolerant wheat lines were screened for rust resistance at both seedling and adult plant stages. Rust resistance genes were characterized through gene matching technique and molecular markers analysis. Yr2 was confirmed in 23 lines, while Yr9 along with Lr26 / Sr31 were postulated in six lines with the help of SRT and molecular markers. Except for KRL2013, none showed complete resistance to all Puccinia striiformis f. sp. tritici (Pst). Lr24/Sr24 genes were confirmed in HD2851 and KRL2029, and Lr13 was detected in a maximum of 24 wheat lines, with varying reaction responses to different leaf rust pathotypes. Several lines carried additional resistance genes such as Sr11 , Sr28 , and Lr68. Lr68 an effective race non-specific APR gene identified in 15 wheat lines with the help of CsGs-STS marker. Although many salt-tolerant wheat lines were susceptible to yellow rust during the seedling stage, a few lines showed APR in the years during 2020 and 2021. Three lines (KRL213, KRL219 and KRL238) showed complete resistance at adult plant stage to leaf rust. These findings offer insights into the genetic basis of rust resistance in salt-tolerant wheat, aiding breeding strategies. [ABSTRACT FROM AUTHOR]

SUMMARY Wheat growth process has been experiencing severe challenges arising from the adverse environment. Notably, the incidence of Fusarium crown rot (FCR), a severe soil‐borne disease caused by Fusarium pseudograminearum (Fp), has significantly intensified in various wheat‐growing regions, resulting in a decline in grain yield. However, the identification of wheat varieties and the exploration of effective gene resources resistant to FCR have not yet been accomplished. Here, we screened and identified the tryptophan metabolism pathway to participate in wheat resistance to FCR by correlation analysis between transcriptome and metabolome, and found that indole‐3‐acetaldehyde (IAAld) and melatonin, two key metabolites in the tryptophan metabolic pathway, were significantly accumulated in Fp‐induced wheat stem bases. Interestingly, exogenous application of these two metabolites could significantly enhance wheat resistance against Fp. Additionally, we observed that the activity of TaALDHase, a crucial enzyme responsible for catalyzing IAAld to produce indole‐3‐acetic acid (IAA), was inhibited. Conversely, the activity of TaMTase, a rate‐limiting involved in melatonin biosynthesis, was enhanced in the Fp‐induced wheat transcriptome. Further analysis showed that TaWRKY24 could regulate IAA and melatonin biosynthesis by inhibiting the expression of TaALDHase and enhancing the transcription of TaMTase, respectively. Silencing of TaALDHase could significantly increase wheat resistance to FCR. However, interference with TaWRKY24 or TaMTase could decrease wheat resistance to FCR. Collectively, our findings demonstrate the crucial role of the tryptophan metabolism pathway in conferring resistance against FCR in wheat, thereby expanding its repertoire of biological functions within the plant system. [ABSTRACT FROM AUTHOR]

SUMMARY Hexokinases (HXKs), which sense and catalyze cellular sugar, play a critical role in the growth and development of various plants, including wheat, a primary source of human calories frequently attacked by fungal pathogens. However, the evolutionary dynamics and functional diversification of HXKs in wheat, particularly their roles in plant defense, remain unclear. Here, we discovered that the wheat hexokinase gene family originated through multiple ancient gene duplications across different plant lineages and has undergone comprehensive, multidimensional functional specialization in gene expression, subcellular localization, enzyme activity, and regulation of plant defense responses. Gene expression analysis suggests that two‐thirds of the TaHXK genes are responsive to fungal infection. Subcellular analysis reveals that while six TaHXKs are localized in mitochondria, three TaHXKs from different phylogenetic branches are sorted into other cellular compartments. Notably, biochemical analysis shows that TaHXKs in mitochondria differ in their glucose‐catalyzing activity, with TaHXK5 and TaHXK3 exhibiting the highest and lowest enzyme activity, respectively. Consistently, transient expression analysis suggests that TaHXK5 induces various plant defense responses, while TaHXK3 is defective in activating some plant defense responses. Furthermore, inactivation of the glucokinase activity of TaHXK5 compromised its function in defense activation, suggesting that mitochondrial TaHXKs display functional divergence in both enzyme activity and defense‐inducing activity that are intrinsically connected. Overall, our findings reveal that the multidimensional specialization events following the ancient duplication events may have shaped the functional diversity of HXKs in wheat, shedding light on their evolutionary dynamics and potentially contributing to the improvement of wheat defense. [ABSTRACT FROM AUTHOR]

Bread wheat (Triticum aestivum) became a globally dominant crop after incorporating the D genome from the donor species Aegilops tauschii , but the evolutionary history that shaped the D genome during this process remains to be clarified. Here, we propose a renewed evolutionary model linking Ae. tauschii and the hexaploid wheat D genome by constructing an ancestral haplotype map covering 762 Ae. tauschii and hexaploid wheat accessions. We dissected the evolutionary trajectories of Ae. tauschii lineages and reported a few independent intermediate accessions, demonstrating that low-frequency inter-sublineage gene flow had enriched the diversity of Ae. tauschii. We discovered that the D genome of hexaploid wheat was inherited from a unified ancestral template, but with a mosaic composition that was highly mixed and derived mainly from three Ae. tauschii L2 sublineages located in the Caspian coastal region. This result suggests that early agricultural activities facilitated innovations in D-genome composition and finalized the success of hexaploidization. We found that the majority (51.4%) of genetic diversity was attributed to novel mutations absent in Ae. tauschii , and we identified large Ae. tauschii introgressions from various lineages, which expanded the diversity of the wheat D genome and introduced beneficial alleles. This work sheds light on the process of wheat hexaploidization and highlights the evolutionary significance of the multi-layered genetic diversity of the bread wheat D genome. By constructing a pan-ancestry haploblock map for the Triticum–Aegilops D genome covering 762 Aegilops tauschii and hexaploid wheat accessions, this study discovered that hexaploid wheat inherited a conserved ancestral genomic template across the D genome. Furthermore, the study elucidated its mosaic composition, which was mainly contributed by three Ae. tauschii L2 sublineages located in the Caspian coastal region. [ABSTRACT FROM AUTHOR]

Summary The abscisic acid (ABA) signalling pathway plays a crucial role in plants’ response to drought stress. In this study, we aimed to characterize the impact of an ABA signalling module, which consisted of TaPYL9 and its downstream partners in Triticum aestivum, on plant drought adaptation. Our results showed that TaPYL9 protein contains conserved motifs and targets plasma membrane and nucleus after being sorted by the endoplasmic reticulum. In addition, TaPYL9 transcripts in both roots and leaves were significantly upregulated in response to drought stress. We conducted glucuronidase (GUS) histochemical staining analysis for transgenic plants carrying a truncated TaPYL9 promoter, which suggested that cis‐elements associate with ABA and drought response, such as ABRE, DRE and recognition sites MYB and MYC, regulating the gene transcription under drought conditions. Using protein interaction assays (i.e., yeast two‐hybrid, bimolecular fluorescence complementation (BiFC), co‐immunoprecipitation (Co‐IP) and in vitro pull‐down), we demonstrated interactions between the intermediate segment of TaPYL9, the intermediate segment of TaPP2C6, the N‐terminus of TaSnRK2.8 and the C‐terminus of the transcription factor TabZIP1 in wheat, indicating the involvement of TaPYL9 in the constitution of an ABA signalling module, namely TaPYL9/TaPP2C6/TaSnRK2.8/TabZIP1. Transgene analysis revealed that TaPYL9, TaSnRK2.8 and TabZIP1 positively regulated drought response, while TaPP2C6 negatively regulated it, and that these genes were closely associated with the regulation of stomata movement, osmolyte accumulation and ROS homeostasis. Electrophoretic mobility shift (EMSA) and transcriptioal activation assays indicated that TabZIP1 interacted promoters of TaP5CS2, TaSLAC1‐1 and TaCAT2 and activated transcription of these genes, which regulated proline biosynthesis, stomata movement and ROS scavenging upon drought signalling, respectively. Furthermore, we found that the transcripts of TaPYL9 and stress‐responsive genes were positively correlated with yields in wheat cultivars under field drought conditions. Altogether, our findings suggest that the TaPYL9‐involved signalling pathway significantly regulates drought response by modulating osmotic stress‐associated physiological processes in T. aestivum. [ABSTRACT FROM AUTHOR]

In the current investigation, the combination of selenium (Se) and epibrassinolide (EBL) exhibited a promising alleviative response against the concurrent stress of heat and drought in wheat plants. The compromised growth and photosynthetic performance of wheat plants under the combined stress of heat and drought were substantially improved with the treatment involving Se and EBL. This improvement was facilitated through the expression of Q9FIE3 and O04939 proteins, along with enhanced antioxidant activities. The heightened levels of antioxidant enzymes and the accumulation of osmoprotectant proline helped mitigate the overaccumulation of reactive oxygen species (ROS), including electrolyte leakage, H2O2 accumulation, and lipid peroxidation, thus conferring tolerance against the combined stress of heat and drought. Studies have demonstrated that Se and EBL can assist wheat plants in recuperating from the adverse effects of heat and drought. As such, they are essential components of sustainable farming methods that aim to increase crop productivity. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) leaf rust [Puccinia triticina (Pt)] causes devastating yield losses globally. Conceivably, breeding and development of cultivars harboring adult plant resistance (APR) to leaf rust (LR) can be an effective way to manage wheat leaf rust. Particularly, mapping of major quantitative trait loci (QTLs) facilitate breeding of LR resistant cultivars. Here, we have mapped QTLs for APR to LR in wheat using wheat population including 215 F2:3 lines from a Zhoumai 22/Chinese Spring. Bulked segregation analyse (BSA) and simple sequence repeat (SSR) detection of wheat lines digged out the QTLs for APR to LR. Using Manager QTXb20 and Icimapping 3.2 software, some APR QTLs were mapped in Zhoumai 22/Chinese Spring wheat population. Three QTLs of APR to LR detected and designated QLr.zh-2BS, QLr.zh-4BL and QLr.zh-7DS) explained 12.58–13.58%, 7.02–20.22% and 6.73–21.30% of the phenotypic variation, respectively. QLr.zh-4BL and QLr.zh-7DS were derived from Chinese Spring wheat, whereas QLr.zh-2BS emanated from Zhoumai 22. QLr.zh-4BL and QLr.zh-7DS were mapped close to Lr12 and Lr34, respectively, revealling their close link to these loci, correspondingly. Overall, the QTLs related APR to LR, their flanking markers and associated APR genes identified in this study could be useful to genomic resources and marker-assisted select breeding of LR resistance in wheat. [ABSTRACT FROM AUTHOR]

As a crucial staple for millions, climate-resilient wheat genotypes are vital for safeguarding livelihoods and ensuring food security. The study encompassed 80 genotypes and was conducted during the Rabi seasons of 2019–2020 and 2020–2021. This study provides a comprehensive analysis of various stress indices to determine their effectiveness in predicting wheat genotypes performance under diverse environmental conditions. Based on strong positive correlation of indices with grain yield per plot along with insights from principal component analysis, our findings showed that the Stress Tolerance Index (STI), Mean Productivity (MP), Geometric Mean Productivity (GMP), Harmonic Mean (HM), and Yield Index (YI) are the most reliable indicators of yield performance under drought, heat, and combined stress conditions. This confirms their effectiveness in selecting resilient genotypes. Additionally, while these indices are robust in predicting performance, it is important to consider their trade-offs with yield stability under stress conditions to ensure a balanced approach in genotype selection. A negative correlation between yield stability index (YSI) and grain yield in favorable conditions suggests that genotypes with high yield stability prioritize consistency over maximum yield potential. The genotypes C-306, HD-2888, GW-477, RW-5, WH-1142, PBW-773 and HD-30 are identified as the best performers under these environmental conditions. The findings highlight the consistent and significant relevance of stress tolerance, stress susceptibility indices, reduction and relative stress index in both PC1 and PC2 explaining the majority of variance within all stress contexts. These revelations offer valuable insights for devising crop enhancement strategies aimed at elevating yield and productivity under diverse stress conditions. Moreover, this knowledge can guide the selection of parental lines for crafting new cultivars with heightened stress tolerance. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during the rabi season (November, 2021-April, 2022) at AICRP on Wheat, College of Agriculture, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India to evaluate the efficacy of Pyroxasulfone in wheat cultivation to enhance crop productivity and profitability. The study assessed eight weed management treatments, including herbicide applications (pendimethalin at 1000 g ha-1; pyroxasulfone at 127.5 g ha-1; pendimethalin+pyroxasulfone at 1250+127.5 g ha-1; metribuzin at 300 g ha-1; pendimethalin+metribuzin at 1250+280 g ha-1; pyroxasulfone+metribuzin at 127.5+280 g ha-1 as pre-emergence), hand weeding once at 25 DAS and weedy check, in a randomized block design with three replications. The experimental field was dominated by Phalaris minor (17.82%) among monocot weeds, while Medicago denticulata (28.97%), Cichorium intybus (26.19%), Chenopodium album (16.10%), and Anagallis arvensis (10.92%) among the dicot weeds throughout the crop growing period. Results revealed a substantial decrease in weed density and dry weight across all treatments, with the combination of pyroxasulfone+metribuzin at 127.5+280 g ha-1 showing superior efficacy. Weed control efficiency was highest with hand weeding, followed by herbicide treatments. Additionally, treatments significantly influenced wheat growth parameters and yield attributes, with the application of pyroxasulfone+metribuzin at 127.5+280 g ha-1 resulting in the tallest plants and highest number of tillers square-1 meter. Grain yield was also found significantly higher in plots treated with pyroxasulfone+metribuzin at 127.5+280 g ha-1. The economic analysis demonstrated that pyroxasulfone+metribuzin at 127.5+280 g ha-1 yielded the highest net monetary returns, indicating its economic viability. [ABSTRACT FROM AUTHOR]

Background and Aims Leaf elongation is vital for productivity of Poaceae species, influenced by atmospheric CO2 concentration ([CO2]) and climate-induced water availability changes. Although [CO2] mitigates the effects of drought on reducing transpiration per unit leaf area, it also increases total leaf area and water use. These complex interactions associated with leaf growth pose challenges in anticipating climate change effects. This study aims to assess [CO2] effects on leaf growth response to drought in perennial ryegrass (Lolium perenne), tall fescue (Festuca arundinacea) and wheat (Triticum aestivum). Methods Plants were cultivated in growth chambers with [CO2] at 200 or 800 ppm. At leaf six to seven unfolding, half of the plants were subjected to severe drought treatment. Leaf elongation rate (LER) was measured daily, whereas plant transpiration was continuously recorded gravimetrically. Additionally, water-soluble carbohydrate (WSC) content along with water and osmotic potentials in the leaf growing zone were measured at drought onset, mid-drought and leaf growth cessation. Key Results Elevated [CO2] mitigated drought impacts on LER and delayed growth cessation across species. A positive correlation between LER and soil relative water content (SRWC) was observed. At the same SRWC, perennial grasses exhibited a higher LER with elevated [CO2], probably due to enhanced stomatal regulation. Despite stomatal closure and WSC accumulation, CO2 did not influence nighttime water potential or osmotic potential. The marked increase in leaf area across species resulted in similar (wheat and tall fescue) or higher (ryegrass) total water use by the end of the experiment, under both watered and unwatered conditions. Conclusions Elevated [CO2] mitigates the adverse effects of drought on leaf elongation in three Poaceae species, due to its impact on plant transpiration. Overall, these findings provide valuable insights into CO2 and drought interactions that may help anticipate plant responses to climate change. [ABSTRACT FROM AUTHOR]

Diabetes is a major health concern and is approaching epidemic proportions worldwide. In 2021, diabetes mellitus was responsible for 6.7 million deaths across the globe. Mortality due to diabetes is predicted to rise nearly 10‐fold by 2030 and 783 million by 2045. Wheat starch, which constitutes about 70% of the endosperm, is a key component of wheat grain. The rapid hydrolysis of wheat starch can result in elevated postprandial glucose levels, leading to diabetes. The increase in blood glucose levels is primarily due to carbohydrate hydrolysis, catalyzed by the enzymes α‐amylase and α‐glucosidase. Although various medications are available for treating diabetes, most of them are costly and may lead to adverse effects. Natural herbs like fenugreek are recommended in traditional medicine for regulating blood glucose levels. This investigation aimed to study the effect of fenugreek seed extract (FSE) on in vitro starch hydrolysis by pancreatic α‐amylase and the ultrastructure of starch. Wheat cultivars were characterized for their total starch, amylose content, and resistant starch content, and were screened for their predicted glycemic index. Microscopic studies were conducted to analyze the size and shape of starch granules and to compare native starch with starch treated with FSE. Significant inhibition of enzymatic starch hydrolysis was observed with FSE, with the maximum inhibitory effect caused by 0.2% FSE. These findings suggest that fenugreek could play a role in controlling blood glucose levels by reducing wheat starch hydrolysis and could be effective in managing diabetes. [ABSTRACT FROM AUTHOR]

• Controversy exists concerning the blood glucose-lowering activity of whole grains. • Whole grains elicit high inter-individual variability in blood glucose tolerance. • Gut microbiota and host metabolism likely influence individuals' responses to whole grains. • Machine learning of multi-omics analyses will help to identify whole grain benefits. • Our planned trial could establish a precision nutrition framework for recommendations. Randomized controlled trials (RCT) demonstrate that whole wheat consumption improves glycemia. However, substantial inter-individual variation is often observed, highlighting that dietary whole grain recommendations may not support the health of all persons. The objective of this report is to describe the rationale and design of a planned RCT aimed at establishing the gut microbiota and metabolome signatures that predict whole wheat-mediated improvements in glucose tolerance in adults with prediabetes. It is hypothesized that a controlled diet containing wheat bread (WHEAT; 160 g/day) compared with refined bread (WHITE) will improve glucose tolerance in a gut microbiota-mediated manner. Biospecimens will be collected before and after each 2-week study arm. Testing for oral glucose tolerance and gastrointestinal permeability will be performed post-intervention. Assessments will include oral glucose tolerance (primary outcome) and secondary outcomes including gut microbiota, targeted and untargeted metabolomics of fecal and plasma samples, intestinal and host inflammatory responses, and intestinal permeability. WHEAT is predicted to alleviate glucose intolerance by shifting microbiota composition to increase short-chain fatty acid-producing bacteria while reducing populations implicated in intestinal inflammation, barrier dysfunction, and systemic endotoxemia. Further, benefits from WHEAT are anticipated to correlate with gut-level and systemic metabolomic responses that can help to explain the expected inter-individual variability in glucose tolerance. Thus, knowledge gained from integrating multi-omic responses associating with glucose tolerance could help to establish a precision nutrition-based framework that can alleviate cardiometabolic risk. This framework could inform novel dietary whole grain recommendations by enhancing our understanding of inter-individual responsiveness to whole grain consumption. This report describes the rationale and design of a planned randomized, controlled trial examining the benefits of WHEAT on glucose tolerance in adults with prediabetes. It is hypothesized that WHEAT will improve glucose tolerance in a gut-mediated manner. Machine learning approaches will identify the metagenomic and metabolomic signatures predicting inter-individual responses to WHEAT. Outcomes are expected to inform a precision nutrition framework for whole wheat to alleviate prediabetes. Abbreviation: WHEAT, whole wheat bread. Created in BioRender. Bruno, R. (2024) BioRender.com/h45v815 [Display omitted] [ABSTRACT FROM AUTHOR]

The coupling of Solid-Phase Microextraction (SPME) technology with gas chromatography (GC) has a well-established and successful history. Traditionally, SPME fibers have been the most popular form thanks to their versatility and the ease with which they can be fully automated. However, alternative geometries for SPME have been developed over the years, beginning with Stir Bar Sorptive Extraction (SBSE) and later evolving into Thin-Film SPME (TF-SPME) devices. Each of these formats offers distinct advantages and disadvantages, which are explored in this study. The primary objective of this study was to comprehensively compare available forms of SPME devices, with a special focus on the advantages of TF-SPME, a novel microextraction method particularly suited for the analysis of odorants in food. The study involved analyzing a standard mixture of 11 key food odorants, representing a range of polarities, to evaluate the efficiency of TF-SPME devices in terms of the number of analytes extracted. Furthermore, four types of TF-SPME devices were compared against each other in both standard mixtures and actual food samples. The final stage of the study employed GCxGC-ToFMS analysis to showcase the potential of the most efficient HLB-TF-SPME device in the non-targeted analysis of complex samples, exemplified by unfiltered wheat beer. This analysis demonstrated the significant capability of HLB-TF-SPME in capturing and identifying a wide range of volatile compounds in complex matrices. [ABSTRACT FROM AUTHOR]

Rye (Secale cereale L.) genes, which contribute to the tertiary gene pool of wheat, include multiple disease resistance genes useful for the genetic improvement of wheat. Introgression lines are the most valuable materials for wheat breeding because of their small alien segments and limited or lack of linkage drag. In the present study, wheat–rye derivative lines SN21627-2 and SN21627-6 were produced via distant hybridization. A genomic in situ hybridization analysis revealed that SN21627-2 and SN21627-6 lack alien segments, while a multi-color fluorescence in situ hybridization analysis detected structural changes in both introgression lines. At the seedling and adult plant stages, SN21627-2 and SN21627-6 were highly resistant to stripe rust and powdery mildew. Primers for 86 PCR-based landmark unique gene markers and 345 rye-specific SLAF markers were used to amplify SN21627-2 and SN21627-6 genomic DNA. Eight markers specific to rye chromosome 2R were detected in both introgression lines, implying these lines carry chromosome 2R segments with genes conferring stripe rust and powdery mildew resistance. Therefore, SN21627-2 and SN21627-6 are resistant to more than one major wheat disease, making them promising bridging parents for breeding disease-resistant wheat lines. [ABSTRACT FROM AUTHOR]

Double B-box (DBB) proteins are plant-specific transcription factors (TFs) that play crucial roles in plant growth and stress responses. This study investigated the classification, structure, conserved motifs, chromosomal locations, cis-elements, duplication events, expression levels, and protein interaction network of the DBB TF family genes in common wheat (Triticum aestivum L.). In all, twenty-seven wheat DBB genes (TaDBBs) with two conserved B-box domains were identified and classified into six subgroups based on sequence features. A collinearity analysis of the DBB family genes among wheat, Arabidopsis, and rice revealed some duplicated gene pairs and highly conserved genes in wheat. An expression pattern analysis indicated that wheat TaDBBs were involved in plant growth, responses to drought stress, light/dark, and abscisic acid treatment. A large number of cis-acting regulatory elements related to light response are enriched in the predicted promoter regions of 27 TaDBBs. Furthermore, some of TaDBBs can interact with COP1 or HY5 based on the STRING database prediction and yeast two-hybrid (Y2H) assay, indicating the potential key roles of TaDBBs in the light signaling pathway. Conclusively, our study revealed the potential functions and regulatory mechanisms of TaDBBs in plant growth and development under drought stress, light, and abscisic acid. [ABSTRACT FROM AUTHOR]

Less than 1% of native prairie lands remain in the United States. Located in eastern Washington, the rare habitat called Palouse prairie was largely converted to wheat monocropping. With this conversion came numerous physical, chemical, and biological changes to the soil that may ultimately contribute to reduced wheat yields. Here, we explored how wheat (Tritcum aestivum L.) seedling establishment, plant size, and heading, signifying the developmental transition to flowering, were affected by being planted in prairie soil versus agricultural soils. We then sought to understand whether the observed effects were the result of changes to the soil microbiota due to agricultural intensification. We found that prairie soil enhanced both the probability of wheat seedling survival and heading compared to agricultural soil; however, wheat growth was largely unaffected by soil source. We did not detect effects on wheat developmental transitions or phenotype when inoculated with prairie microbes compared with agricultural microbes, but we did observe general antagonistic effects of microbes on plant size, regardless of soil source. This work indicates that agricultural intensification has affected soils in a way that changes early seedling establishment and the timing of heading for wheat, but these effects may not be caused by microbes, and instead may be caused by soil nutrient conditions. [ABSTRACT FROM AUTHOR]

SUMMARY: A series of polyploidizations in higher‐order polyploids is the main event affecting gene content in a genome. Each polyploidization event can lead to massive functional divergence because of the subsequent decrease in selection pressure on duplicated genes; however, the causal relationship between multiple rounds of polyploidization and the functional divergence of duplicated genes is poorly understood. We focused on the Triticum–Aegilops complex lineage and compared selection pressure before and after tetraploidization and hexaploidization events. Although both events led to decreased selection pressure on homoeologous gene pairs (compared with diploids and tetraploids), the initial tetraploidization had a greater impact on selection pressure on homoeologous gene pairs than did subsequent hexaploidization. Consistent with this, selection pressure on expression patterns for the initial event relaxed more than those for the subsequent event. Surprisingly, the decreased selection pressure on these homoeologous genes was independent of the existence of in‐paralogs within the same subgenome. Wheat homoeologous pairs had different evolutionary consequences compared with orthologs related to other mechanisms (ancient allopolyploidization, ancient autopolyploidization, and small‐scale duplication). Furthermore, tetraploidization and hexaploidization also seemed to have different evolutionary consequences. This suggests that homoeologous genes retain unique functions, including functions that are unlikely to be preserved in genes generated by the other duplication mechanisms. We found that their unique functions differed between tetraploidization and hexaploidization (e.g., reproductive and chromosome segregation processes). These findings imply that the substantial number of gene pairs resulting from multiple allopolyploidization events, especially initial tetraploidization, may have been a unique source of functional divergence. [ABSTRACT FROM AUTHOR]