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Background: Fusarium head blight (FHB), caused by Fusarium graminearum, is a major disease of wheat in North America. FHB infection causes fusarium damaged kernels (FDKs), accumulation of deoxynivalenol (DON) in the grain, and a reduction in quality and grain yield. Inheritance of FHB resistance is complex and involves multiple genes. The objective of this research was to identify QTL associated with native FHB and DON resistance in a 'D8006W'/'Superior', soft white winter wheat population. Results: Phenotyping was conducted in replicated FHB field disease nurseries across multiple environments and included assessments of morphological and FHB related traits. Parental lines had moderate FHB resistance, however, the population showed transgressive segregation. A 1913.2 cM linkage map for the population was developed with SNP markers from the wheat 90 K Infinium iSelect SNP array. QTL analysis detected major FHB resistance QTL on chromosomes 2D, 4B, 5A, and 7A across multiple environments, with resistance from both parents. Trait specific unique QTL were detected on chromosomes 1A (visual traits), 5D (FDK), 6B (FDK and DON), and 7D (DON). The plant height and days to anthesis QTL on chromosome 2D coincided with Ppd-D1 and were linked with FHB traits. The plant height QTL on chromosome 4B was also linked with FHB traits; however, the Rht-B1 locus did not segregate in the population. Conclusions: This study identified several QTL, including on chromosome 2D linked with Ppd-D1, for FHB resistance in a native winter wheat germplasm. [ABSTRACT FROM AUTHOR]

Crop statistics are crucial for developing a demand-based export and import strategy to ensure a country's sustainable food security. Remote sensing efficiently generates essential crop statistics, while ground-based supplementary sensor data offers sufficient information for crop delineation. This study explored the multispectral satellite imagery using in-situ ground-based hyperspectral reflectance phenology information as training data to delineate wheat from other competitive winter crops in Northwestern Bangladesh as a case study. Wheat spectral signatures were primarily obtained through a hand-held Spectroradiometer at various phenological stages, aligned with Sentinel-2 data availability. Five vegetation indices (VIs), namely Normalized Difference Vegetation Index (NDVI), Red-edge NDVI (RENDVI), Enhanced Vegetation Index (EVI), Greenness Chromatic Coordinate (GCC) and Soil-Adjusted Vegetation Index (SAVI), were derived from Spectroradiometer-data across six wheat growth stages: seedling, tillering, booting, flowering, grain development, and maturity. Maximum and minimum threshold values for the VIs at those six growth stages were determined from regression analysis of the values collected from Spectroradiometer and Sentinel-2. A rule-based classification technique was then used to categorize Sentinel-2 for wheat crop delineation based on those threshold values. The results revealed that maps based on NDVI, EVI, and SAVI showed overall accuracies of 83.33%, 85.18%, and 81.48%, respectively. These accuracies were found to be statistically acceptable (p < 0.05) outcomes. A positive agreement was observed when comparing the remotely sensed area at the union (4th tier administrative level) with the officially reported data of Bangladesh. This innovative method has the potential to be extended for developing phenology and area delineation for other major crops locally and globally. Highlights: A phenology-based algorithm was applied for delineating winter wheat. The algorithm is developed by combining Sentinel-2 images and Spectroradiometer data. Vegetative indices of wheat exhibited a strong relationship between two sensors' data. Accuracy assessment and validation of the produced maps demonstrated significant results. The method has the potential to be extended to area mapping for other crops locally and globally. [ABSTRACT FROM AUTHOR]

Background: Inulin and inulin-derived fructooligosaccharides (FOS) are well-known prebiotics for use in companion animals and livestock. The mechanisms by which FOS contribute to health has not been fully established. Further, the fine chemistry of fructan structures from diverse sources, such as graminan-type fructans found in cereal crops, has not been fully elucidated. New methods to study fructan structure and microbial responses to these complex carbohydrates will be key for evaluating the prebiotic potency of cereal fructans found in cattle feeds. As the rumen microbiome composition is closely associated with their metabolic traits, such as feed utilization and waste production, prebiotics and probiotics represent promising additives to shift the microbial community toward a more productive state. Results: Within this study, inulin, levan, and graminan-type fructans from winter wheat, spring wheat, and barley were used to assess the capacity of rumen-derived Bifidobacterium boum, Bifidobacterium merycicum, and Lactobacillus vitulinus to metabolize diverse fructans. Graminan-type fructans were purified and structurally characterized from the stems and kernels of each plant. All three bacterial species grew on FOS, inulin, and cereal crop fructans in pure cultures. L. vitulinus was the only species that could metabolize levan, albeit its growth was delayed. Fluorescently labelled polysaccharides (FLAPS) were used to demonstrate interactions with Gram-positive bacteria and confirm fructan metabolism at the single-cell level; these results were in agreement with the individual growth profiles of each species. The prebiotic potential of inulin was further investigated within naïve rumen microbial communities, where increased relative abundance of Bifidobacterium and Lactobacillus species occurred in a dose-dependent and temporal-related manner. This was supported by in situ analysis of rumen microbiota from cattle fed inulin. FLAPS probe derived from inulin and fluorescent in situ hybridization using taxon-specific probes confirmed that inulin interacts with Bifidobacteria and Lactobacilli at the single-cell level. Conclusion: This research revealed that rumen-derived Bifidobacteria and Lactobacilli vary in their metabolism of structurally diverse fructans, and that inulin has limited prebiotic potential in the rumen. This knowledge establishes new methods for evaluating the prebiotic potential of fructans from diverse plant sources as prebiotic candidates for use in ruminants and other animals. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted at Lovely Professional University, Phagwara during the Rabi season of 2018–2019 and 2019-20 to study the effect of crop establishment methods and sowing schedule on the growth and yield of wheat under the rice-wheat cropping system. The experiment comprised different rice residue management-based wheat establishment methods, sowing dates, and varying nitrogen levels. The results confirmed that growth, yield and yield attributes were all influenced by different crop establishment methods, sowing dates and level of nitrogen application. The results showed that maximum plant height, number of tillers per plant, number of spikes per plant, spike length, number of grains per spike and grain yield were observed under 20th November sowing (timely sowing) and with 100% RDN (recommended dose of nitrogen). Moreover, the maximum number of spikes per plant, spike length and grain yield were significantly highest for the residue incorporation method of wheat establishment. The optimum time of sowing also improved the grain yield of wheat. Among the different crop establishment methods, the best attainment of available nitrogen status in soil was found in residue incorporation treatment. [ABSTRACT FROM AUTHOR]

A multiplicity of substantial disruptions in the physiological systems of the wheat crop (Triticum aestivum L.) are the result of a potassium deficiency.The foliar application of potassium improves the quality of wheat and the production of grains for end-use purposes. This study was carried out during the growing seasons of 2021-22 to investigate the response of winter wheat cultivars to foliar application of potassium (0, 1, and 2 g/L), at two growth stages (green up and heading) on the grain yield (t/ha), protein content (%), specific weight and plant vegetative indicators (chlorophyll content, flag leaf area and plant height). Foliar applications of potassium fertilizer were implemented at concentrations of (0, 1 and 2 g/L). The treatments were applied at both the tillering and flowering stages. Potassium treatments, wheat cultivars, and their interactions significantly differed in most measured parameters. Application of 2g/L of K increases grain yield, protein content, and plant height than 0, 1 g/L by 5.51 t/ha, 10.52% and 95.60 cm, respectively. Foliar application of nano-potassium timed at both tillering and flowering stages would be beneficial in improving the yield and its component. Furthermore, the various trait responses of cultivars to K application can be attractive to wheat breeders for selection. [ABSTRACT FROM AUTHOR]

Zinc (Zn) fertilization of hard red and soft white winter wheat (Triticum aestivum L.) is uncommon in the low precipitation zone of the inland Pacific Northwest. It is uncommon because there have been no indications of deficiency. Soil test data, however, show Zn levels have been declining over time. We conducted a four‐site‐year experiment to evaluate effects of fertilization on early‐season tissue Zn concentration (TZC), dry matter accumulation (DMA), Zn uptake (ZNU), the grain test weight (TWT), protein content (PRO), and yield (YLD) of two regionally adapted cultivars. Planting occurred late in September or early in October. Zinc fertilizer, placed with the seed while planting, was applied at rates of 0 and 5 kg Zn ha−1. Application of 5 kg Zn ha−1 increased TZC and ZNU at one of two sites. There were corresponding trends of increased DMA and improved YLD. Response to fertilization occurred on a relatively shallow soil that had a diethylenetriamine‐pentaacidic acid–extractable Zn test level of 0.3 mg kg−1. Core Ideas: Zinc fertilization increased tissue Zn concentration and Zn uptake in winter wheat (Triticum aestivum L.) at one of two experimental sites.There were corresponding treatment‐induced trends of increased dry matter accumulation and improved grain yield.Response to fertilization occurred on a relatively shallow soil that had a diethylenetriamine‐pentaacidic acid‐extractable soil test Zn level of 0.3 mg kg−1.Response to fertilization may have been due, at least in part, to the near‐surface position of carbonates and alkalinity. [ABSTRACT FROM AUTHOR]

The optimized sowing method and appropriate seed rate can improve wheat N use efficiency. However, the interactive effect of the sowing method and seed rate on N use efficiency, particularly N uptake and root length density, are unclear. A field experiment was conducted for two growing seasons in southern Shanxi province, China, using a split-plot design with the sowing method as the main plot (wide-belt sowing, WBS, and conventional narrow-drill sowing, NDS) and seed rate as the sub-plot (100–700 m−2). Our results showed that WBS had a significant and positive effect on N use efficiency (yield per unit of available N from the fertilizer and soil, by 4.7–15.4%), and the relatively higher seed rates (>300 or 400 m−2) enlarged the effects. The N use efficiency increases under WBS were mainly attributed to the increases in N uptake before anthesis, resulting from the promoted nodal roots per plant and per unit area, and root length density in the top layer(s). WBS promoted N translocation and the N harvest index, resulting in equivalent grain protein concentration and processing quality compared to NDS. Thus, adopting higher seed rates (>300 m−2) combined with WBS is recommended for achieving greater N efficiencies while maintaining the grain protein concentration and processing quality of winter wheat. [ABSTRACT FROM AUTHOR]

With an increase in the frequency of hot-dry-windy weather and reported significant increase in winter wheat (Triticum aestivum L.) in-season average temperatures, it is important to understand how soil management affects yield stability. This study quantified the combined effects of tillage and fertilizer-N on winter wheat yield stability in a wheat–sorghum [Sorghum bicolor (L.) Moench]–fallow crop rotation. The research was conducted from 1975 to 2022 and the experimental design was a randomized complete block with a split-split-plot arrangement. Crop phases were the main plots, tillage (conventional tillage [CT], reduced tillage [RT], and no-tillage [NT]) in the sub-plot, and N application rates (0, 22, 45, and 67 kg N ha−1 or 0, 45, 90, and 134 kg N ha−1) in the sub-sub-plot. Results showed winter wheat yield under NT increased by 0.8 Mg ha−1, compared with about 1.1 Mg ha−1 for CT and RT, when environmental average increased by 1 Mg ha−1 for N rates ≤90 kg ha−1. Yields with CT and RT increased by 0.8 Mg ha−1, compared with about 1.1 Mg ha−1 rate for NT, when environmental average increased by 1 Mg ha−1 for N >90 kg ha−1. In 30%–52% of the time, CT wheat yield was greater than NT, but yield advantage with CT decreased as fertilizer-N rate increases. Yield stability of winter wheat varied by tillage and fertilizer rate. We concluded that NT wheat required greater N rates to reach the same yield potential as CT and RT, and long-term CT or RT wheat at 45 kg N ha−1 was most stable [ABSTRACT FROM AUTHOR]

Low-temperature flooding and ice encasement (LTFIE) cause variable survival of winter wheat (Triticum aestivum L.) in Ontario, which limits the adoption of wheat into crop rotations by growers. The development of novel cultivars capable of withstanding LTFIE is a promising avenue for improvement, but the methods used to assess the survival of winter wheat under LTFIE are restricted. This study developed updated methods to determine the survival of wheat cultivars under LTFIE using controlled environments and, to our knowledge, is the first method since the 1980s to use Canadian eastern soft red winter wheat (CESRW) to conduct cold tolerance studies. Chamber-acclimated plants of AC Carberry (spring wheat control), Branson (CESRW), CM614 (CESRW), and Norstar (hardy Canadian western red winter control) cultivars were used to estimate the days (LD50) and temperature (LT50) to reach 50% mortality under ice and without ice treatments. Norstar had the longest LD50 at 33 days, Branson and CM614 had similar LD50 of 18 and 20 days, and AC Carberry did not reach an LD50 as it died early in both treatments. The LT50 of each cultivar was different; Norstar had the lowest LT50 (−13.6 °C day 0 and −13.2 °C day 7), and AC Carberry had the highest LT50 (−6.6 °C day 0 and −2.7 °C day 7). The detailed methods developed in this study were more reliable compared to older methods based on the more accurate reported LD50 and LT50 of the cultivars, therefore, these methods can be used to screen winter cereals for LTFIE in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: The continuous cultivation of rice–wheat in the same field is a key element of double‐cropping systems in the Indo‐Gangetic plains. Yields of such cropping systems are increasingly challenged as climate change drives increases in temperature, terminal stress and uneven rainfall, delaying rice harvesting and subsequently delaying sowing of wheat. In this paper, we evaluate the optimum sowing dates to achieve high grain yield and quality of wheat cultivars in northwest India. Three cultivars of wheat, HD‐2967, HD‐3086 and PBW‐723, were sown on three different dates at the research farm of ICAR‐IARI, New Delhi, to generate different weather conditions at different phenological stages. Different biophysical attributes, photosynthetic rate, stomatal conductance and transpiration rate, were measured at different phenological stages. Yield and grain quality parameters such as protein, starch, amylopectin, amylose and gluten were measured in different cultivars sown on different dates. RESULTS: Biophysical parameters were found to be higher in timely sown crops followed by late‐sown and very late‐sown crops. Further, the different sowing dates had a significant (P < 0.05) impact on the grain quality parameters such as protein, starch, amylopectin, amylose and gluten content. Percentage increases in the value of starch and amylose content under timely sown were ~7% and 11.6%, ~5% and 8.4%, compared to the very late‐sown treatment. In contrast, protein and amylopectin contents were found to increase by ~9.7% and 7.5%, ~13.8% and 16.6% under very late‐sown treatment. CONCLUSION: High‐temperature stress during the grain‐filling periods significantly decreased the grain yield. Reduction in the grain yield was associated with a reduction in starch and amylose content in the grains. The protein content in the grains is less affected by terminal heat stress. Cultivar HD‐3086 had higher growth, yield as well as quality parameters, compared to HD‐2967 and PBW‐723 in all treatments, hence could be adopted by farmers in northwest India. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The water absorption capacity (WAC) of hard wheat (Triticum aestivum L.) flour affects end‐use quality characteristics, including loaf volume, bread yield, and shelf life. However, improving WAC through phenotypic selection is challenging. Phenotyping for WAC is time consuming and, as such, is often limited to evaluation in the latter stages of the breeding process, resulting in the retention of suboptimal lines longer than desired. This study investigates the potential of univariate and multivariate genomic predictions as an alternative to phenotypic selection for improving WAC. A total of 497 hard winter wheat genotypes were evaluated in multi‐environment advanced yield and elite trials over 8 years (2014–2021). Phenotyping for WAC was done via the solvent retention capacity (SRC) using water as a solvent (SRC‐W). Traits that exhibited a significant correlation (r ≥ 0.3) with SRC‐W and were evaluated earlier than SRC‐W were included in the multivariate genomic prediction models. Kernel hardness and diameter were obtained using the single kernel characterization system (SKCS), and break flour yield and total flour yield (T‐Flour) were included. Cross‐validation showed the mean univariate genomic prediction accuracy of SRC to be r = 0.69 ± 0.005, while bivariate and multivariate models showed an improved prediction accuracy of r = 0.82 ± 0.003. Forward validation showed a prediction accuracy up to r = 0.81 for a multivariate model that included SRC‐W + All traits (SRC‐W, Diameter, SKCS hardness and diameter, F‐Flour, and T‐Flour). These results suggest that incorporating correlated traits into genomic prediction models can improve early‐generation prediction accuracy. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Leaf area index (LAI) is an important indicator for assessing plant growth and development, and is also closely related to photosynthesis in plants. The realization of rapid accurate estimation of crop LAI plays an important role in guiding farmland production. In study, the UAV‐RGB technology was used to estimate LAI based on 65 winter wheat varieties at different fertility periods, the wheat varieties including farm varieties, main cultivars, new lines, core germplasm and foreign varieties. Color indices (CIs) and texture features were extracted from RGB images to determine their quantitative link to LAI.The results revealed that among the extracted image features, LAI exhibited a significant positive correlation with CIs (r = 0.801), whereas there was a significant negative correlation with texture features (r = −0.783). Furthermore, the visible atmospheric resistance index, the green–red vegetation index, the modified green–red vegetation index in the CIs, and the mean in the texture features demonstrated a strong correlation with the LAI with r > 0.8. With reference to the model input variables, the backpropagation neural network (BPNN) model of LAI based on the CIs and texture features (R2 = 0.730, RMSE = 0.691, RPD = 1.927) outperformed other models constructed by individual variables.This study offers a theoretical basis and technical reference for precise monitor on winter wheat LAI based on consumer‐level UAVs. The BPNN model, incorporating CIs and texture features, proved to be superior in estimating LAI, and offered a reliable method for monitoring the growth of winter wheat. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Drought stress has serious effects on the growth and yield of wheat in both productivity and quality and is an abiotic factor. Traditional methods of crop drought stress monitoring have some deficits. This work has been conducted in order to enhance these conventional methods by proposing a new deep learning approach. This paper has presented a deep learning-based model customized for monitoring drought stress in winter wheat during the critical growth stages. Drought-afflicted winter wheat images were captured at three crucial phases: rising–jointing, heading–flowering, and flowering–maturity. These images are correlated against soil moisture data to construct a comprehensive dataset. DenseNet121 was chosen as the network model since it extracts features from images relating to phenotypes. Several factors, like training methods, learning rate adjustment, and addition of the attention mechanism, are optimized in eight sets of experiments. This provided the final DenseNet-121 model with an average recognition accuracy of 94.67% on the test set, which means that monitoring drought stress during wheat growth's key periods is feasible and effective. [ABSTRACT FROM AUTHOR]

Plant height, spike, leaf, stem and grain morphologies are key components of plant architecture and related to wheat yield. A wheat (Triticum aestivum L.) mutant, wpa1, displaying temperature-dependent pleiotropic developmental anomalies, was isolated. The WPA1 gene, encoding a von Willebrand factor type A (vWA) domain protein, was located on chromosome arm 7DS and isolated by map-based cloning. The functionality of WPA1 was validated by multiple independent EMS-induced mutants and gene editing. Phylogenetic analysis revealed that WPA1 is monocotyledon-specific in higher plants. The identification of WPA1 provides opportunity to study the temperature regulated wheat development and grain yield. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA), a vital endogenous hormone, plays a crucial role in plant growth and the response to abiotic and biotic stress. Isochorismate synthase (ICS) and phenylalanine ammonia lyase (PAL) are critical rate-limiting enzymes for SA synthesis. Fusarium head blight (FHB) seriously threatens the safety of wheat production, but increasing the content of SA can enhance FHB resistance. However, the pathway of SA synthesis and regulation in wheat remains unknown. In this study, three wheat ICS (TaICSA, TaICSB, and TaICSD) were identified, and their functions were validated in vitro for isomerizing chorismate to isochorismate. The mutation of one or two homoeoalleles of TaICSA, TaICSB, and TaICSD in the wheat variety 'Cadenza' reduced SA levels under ultraviolet treatment and Fusarium graminearum infection, further enhancing sensitivity to FHB. Overexpression of TaICSA can significantly enhance SA levels and resistance to FHB. To further study SA synthesis pathways in wheat and avoid interference with pathogenicity related genes, the leaves of wild-type Cadenza and different TaICS mutant lines were subjected to ultraviolet treatment for transcriptomic analysis. The results showed that 37 PALs might be involved in endogenous SA synthesis, and 82 WRKY and MYB family transcription factors may regulate the expression of ICS and PAL. These results were further confirmed by RT-PCR. In conclusion, this study expands our knowledge of SA biosynthesis and identifies TaICSA, as well as several additional candidate genes that encode transcription factors for regulating endogenous SA levels, as part of an efficient strategy for enhancing FHB resistance in wheat. [ABSTRACT FROM AUTHOR]

Promoting more floret primordia within a spike to acquire fertile potential during the differentiation and pre-dimorphism phases is critical for increasing the number of fertile florets per spike (NFFs). However, it is yet unknown the physiological mechanism regulating the complex and dynamic process. This study aimed to clarify how intra-spike hormones, pigments, and assimilates coordinate with each other to regulate spike morphology and then floret primordia development. A two-year field experiment was conducted with two winter wheat genotypes: N50 (big-spike with greater NFFs) and SM22 (mediumspike with fewer NFFs). We monitored high temporal and spatial-resolution changes in the number and morphology of floret primordia within a spike, as well as in intra-spike hormones, pigments, and assimilates. Our results revealed that the big-spike genotype had more NFFs than the medium-spike genotype, not only because they had more spikelets, but also because they had greater NFFs mainly at central spikelets. More floret primordia at central spikelets had sufficient time to develop and acquire fertile potential during the differentiation phase (167-176 d after sowing, DAS) and the pre-dimorphism phase (179 DAS) for the big-spike genotype than the medium-spike genotype. Floret primordia with fertile morphology during the pre-dimorphism phase always developed into fertile florets during the dimorphism phase. Those early-developed floret primordia most proximal and intermediate to the rachis in the big-spike genotype developed faster than the medium-spike genotype. Correspondingly, the spike dry matter and pigments (chlorophyll a, chlorophyll b, carotene, and carotenoids) content during 170-182 DAS, auxin (IAA) and cytokinin (CTK) content on 167 DAS were significantly higher in the big-spike genotype than in the medium-spike genotype, while jasmonic acid (JA) content was significantly lower in the big-spike genotype compared to the medium-spike genotype during 167-182 DAS. Since the significant differences in intra-spike hormone content of the two genotypes appear earlier than those in dry matter and pigments, we propose a possible model that helped the N50 genotype (big-spike) to form more fertile florets, taking the intra-spike hormone content as a signaling molecule induced assimilates and pigments synthesis, which accelerated the development of more floret primordia during the differentiation phase and then acquired fertile potential during the pre-dimorphism phase, finally improved the NFFs. Our high temporal and spatial-resolution analysis provides an accurate time window for precision cultivation and effective physiological breeding to improve the number of fertile florets in wheat. [ABSTRACT FROM AUTHOR]

To non-destructively and rapidly monitor the chlorophyll content of winter wheat leaves under CO2 microleakage stress, and to establish the quantitative relationship between chlorophyll content and sensitive bands in the winter wheat growing season from 2023 to 2024, the leakage rate was set to 1 L/min, 3 L/min, 5 L/min, and 0 L/min through field experiments. The dimensional reduction was realized, fractional differential processing of a wheat canopy spectrum was carried out, a multiple linear regression (MLR) and partial least squares regression (PLSR) estimation model was constructed using a SPA selection band, and the model's accuracy was evaluated. The optimal model for hyperspectral estimation of wheat SPAD under CO2 microleakage stress was screened. The results show that the spectral curves of winter wheat leaves under CO2 microleakage stress showed a "red shift" of the green peak and a "blue shift" of the red edge. Compared with 1 L/min and 3 L/min, wheat leaves were more affected by CO2 at 5 L/min. Evaluation of the accuracy of the MLR and PLSR models shows that the MLR model is better, where the MLR estimation model based on 1.1, 1.8, 0.4, and 1.7 differential SPAD is the best for leakage rates of 1 L/min, 3 L/min, 5 L/min, and 0 L/min, with validation set R2 of 0.832, 0.760, 0.928, and 0.773, which are 11.528, 14.2, 17.048, and 37.3% higher than the raw spectra, respectively. This method can be used to estimate the chlorophyll content of winter wheat leaves under CO2 trace-leakage stress and to dynamically monitor CO2 trace-leakage stress in crops. [ABSTRACT FROM AUTHOR]

Food and feed production worldwide heavily relies on wheat (Triticum aestivum). However, current agricultural practices face numerous challenges including a shortage of land for cultivation, a desire to reduce the use of chemical pesticides and fertilizers, and the development of resistance towards employed pesticides and virulence towards host resistance in the most widely grown varieties. In this paper, we demonstrate based on the literature that cultivating wheat variety mixtures generally leads to increased yield and yield stability across years and environments, reduced severity of multiple diseases, and a decreased risk of lodging before harvest compared to the cultivation of pure stands. Moreover, mixtures may delay fungicide resistance development and increase genetic diversity, ultimately prolonging the durability of resistance genes. Furthermore, growing mixtures may lower the risk of crop failure due to more extreme weather events and lead to better utilization of water and nutrients. We discuss a Danish case study advocating the cropping of wheat varieties in mixtures as an example of how variety mixtures can be utilized in integrated pest management strategies. The study shows that if all involved stakeholder groups promote the adoption of variety mixtures, a major uptake by farmers can be reached, potentially reducing the dependency on pesticides in current cropping schemes. [ABSTRACT FROM AUTHOR]

A simulation study was conducted for assessing the climate change impact on wheat cultivars (HD2967 and PBW725) under RCP 4.5 and RCP 6.0 scenarios for four agroclimatic zones (AZ) of Punjab. The yield trend during 70 years (2025–95) using the CERES‐Wheat model was assessed for different sowing windows (end October to end November). The maximum/minimum temperature and rainfall, respectively, during the season varied between 25–27°C/9–12°C and 27–103 mm (AZ II), 24–27°C/8–13°C and 37–105 mm (AZ III), 24–26°C/9–12°C and 20–80 mm (AZ IV) and 23–26°C/9–12°C and 30–71 mm (AZ V). The climatic conditions largely vary across the state, because of which only AZs II, III and V were found productive for wheat crop with most of the years lying in the high yield (>5000 kg/ha) category. The sowing of HD2967 during mid to end November would be suitable adaptation strategy for wheat growers in the state. [ABSTRACT FROM AUTHOR]

The genus Clavibacter (family Microbacteriaceae) includes gram‐positive actinobacterial species infecting diverse agricultural crops such as alfalfa, maize, pepper, potato, tomato and wheat. Clavibacter tessellarius, causing bacterial mosaic of wheat, was reported for the first time in 1976 in Nebraska (United States). Since then, the pathogen was thought to be restricted to North America (Canada and the United States). While bacterial strains suspected to be C. tessellarius have occasionally been isolated from wheat samples outside North America, occurrence of the pathogen in the Old World has not yet been confirmed by the plant protection authorities. In spring 2020 (January to May) dozens of wheat fields with young plants showing leaf chlorosis and mild mosaic symptoms were surveyed and sampled in southern Iran. Among 192 surveyed wheat fields, gram‐positive, orange‐pigmented actinobacterial strains were isolated from samples of 53 fields. Altogether, 61 bacterial strains were identified as C. tessellarius based on the phenotypic features, PCR‐based molecular tests and pathogenicity assays. Multilocus sequence analysis of five housekeeping genes (atpD, dnaK, gyrB, ppk and rpoB) using 10 representative strains from diverse geographic areas in southern Iran confirmed the phylogenetic status of the strains within C. tessellarius. Our data indicate that the bacterial mosaic pathogen occurs in four southern Iranian provinces including Bushehr, Fars, Kerman and Khuzestan. Thus, occurrence of C. tessellarius outside North America is confirmed. Potential risks associated with the emergence of the pathogen in the Old World, and the need for strict quarantine measures in the area, is further discussed. [ABSTRACT FROM AUTHOR]

Unprecedented precipitation deficits in the 2022-2023 growing season across the primary wheat-producing region in the United States caused delays in winter wheat emergence and poor crop growth. Using an integrated approach, we quantitatively unraveled a 37% reduction in wheat production as being attributable to both per-harvested acre yield loss and severe crop abandonment, reminiscent of the Dust Bowl years in the 1930s. We used random forest machine learning and game theory analytics to show that the main driver of yield loss was spring drought, whereas fall drought dominated abandonment rates. Furthermore, results revealed, across the US winter wheat belt, the La Niña phase of the El Niño Southern Oscillation (ENSO), increased abandonment rates compared to the El Niño phase. These findings underscore the necessity of simultaneously addressing crop abandonment and yield decline to stabilize wheat production amid extreme climatic conditions and provide a holistic understanding of global-scale ENSO dynamics on wheat production. [ABSTRACT FROM AUTHOR]

BACKGROUND: Japanese brome (Bromus japonicus Thumb.) is one of the problematic annual weeds in winter wheat (Triticum aestivum L.) and is generally controlled by acetolactate synthase (ALS) inhibitors. Repeated use of the ALS inhibitor propoxycarbazone‐Na resulted in the evolution of resistance to this herbicide in three B. japonicus populations, i.e., R1, R2, and R3 in Kansas (KS). However, the level of resistance and mechanism conferring resistance in these populations is unknown. The objectives of this research were to (i) evaluate the level of resistance to propoxycarbazone‐Na in R1, R2, and R3 in comparison with a known susceptible population (S1), (ii) investigate the mechanism of resistance involved in conferring ALS‐inhibitor resistance, and (iii) investigate the cross‐resistance to other ALS inhibitors. RESULTS: Dose–response (0 to 16x; x = 44 g ai ha−1 of propoxycarbazone‐Na) assay indicated 167, 125, and 667‐fold resistance in R1, R2 and R3 populations, respectively, compared to S1 population. ALS gene sequencing confirmed the mutations resulting in amino acid substitutions, i.e., Pro‐197‐Thr (R3, R1)/Ser (R2, R1) bestowing resistance to these ALS inhibitors. Such amino acid substitutions also showed differential cross‐resistance to sulfosulfuron, mesosulfuron‐methyl, pyroxsulam, and imazamox among resistant populations. Pretreatment with malathion (a cytochrome P450 enzyme‐inhibitor) followed by imazamox treatment suggested cross‐resistance to this herbicide possibly via metabolism only in R3 population. CONCLUSION: Overall, these results confirm the first case of target‐site based resistance to ALS inhibitors in B. japonicus in the US, highlighting the need for exploring herbicides with alternative modes of action to enhance weed control in winter wheat. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Heat stress represents a significant environmental challenge that adversely impacts the growth, physiology, and productivity of wheat. In order to determine the response to high temperatures of the wheat varieties developed mostly in the Pannonian environmental zone, as well as varietal differences, we subjected seven varieties from Serbia, one from Australia, and one from the UK to thermal stress during anthesis and mid-grain filling and combined stress during both of these periods. The changes in chlorophyll fluorescence and index, leaf temperature, and main agronomic traits of nine winter wheat varieties were investigated under high temperatures. Heat stress negatively affected leaf temperature, chlorophyll fluorescence, and the chlorophyll index during different growth stages. Compared to the control, stress at anthesis, mid-grain filling, and combined stress resulted in yield reductions of 32%, 46%, and 59%, respectively. Single treatment at anthesis had a more severe effect on the number of grains per plant, causing a 38% reduction compared to the control. Moreover, single treatment during mid-grain filling resulted in the greatest decline in grain weight, with a 29% reduction compared to the control. There was a significant varietal variation in heat tolerance, highlighting Avangarda and NS 40s as the most tolerant varieties that should be included in regular breeding programs as valuable sources of heat tolerance. Understanding the genetic and physiological mechanisms of heat tolerance in these promising varieties should be the primary focus of future research and help develop targeted breeding strategies and agronomic practices to mitigate the adverse effects of heat stress on wheat production. [ABSTRACT FROM AUTHOR]

Explicitly representing the world's most frequently cultivated winter wheat in land surface model (LSM) is important for understanding carbon and energy cycling over cropland and its interactions with climate, which is crucial for global food security. However, in the latest version of Noah‐MP‐Crop LSM, winter wheat is significantly underrepresented. This study improved the winter‐wheat parameterization in Noah‐MP‐Crop model by optimizing the phenological scheme, incorporating vernalization process, and calibrating several key parameters associated with winter wheat photosynthesis and carbon allocations. Focusing on the North China Plain as area representative region, model performance in simulating crop dynamic growth, carbon flux, and energy fluxes was validated at both site and regional scales. Results showed that the simulated phenological development matched well with the real‐world phenological records. A comparison between the simulated results by the default and developed parameterizations revealed the significant improvements in the reproductions of leaf area index (LAI) and gross primary production (GPP). The determination coefficient (R2) value of GPP was increased from 0.15 to 0.46 to 0.39–0.91. Simulations of energy fluxes showed smaller improvements, with R2 values increasing from 0.46 to 0.67 to 0.61–0.84 for latent heat (LE) and 0.18–0.55 to 0.25–0.61 for sensible heat. Additionally, the mean average error of net radiation was reduced. Improvements in spatial and temporal variations of LAI, GPP, and LE in regional simulation were also observed. This work can facilitate incorporating winter wheat cultivation and its interactions with climate system, particularly when coupling the Noah‐MP‐Crop model with the widely used Weather Research and Forecasting model. Plain Language Summary: Winter wheat is a widely cultivated staple food that plays a crucial role in ensuring food security worldwide. However, its representation in land surface models (LSMs), for example, in the latest version of the Noah‐MP‐Crop LSM, is less developed compared to spring wheat due to the longer growing season and over‐wintered growth characteristics. This hinders the application of these models in studying surface carbon and energy cycling, which have a significant impact on climate, particularly in regions dominated by winter wheat production. To address this issue, we improved the parameterization of winter wheat in the Noah‐MP‐Crop model by redefining the phenological stages, adjusting the thresholds for entering each stage, incorporating the vernalization process, and optimizing key parameters related to photosynthesis and carbon allocations. We evaluated the improved parameterization by comparing simulated winter wheat growth, carbon and energy cycles with in situ observations and satellite‐derived products. The results demonstrated significant improvements in leaf area index and gross primary productivity of winter wheat, but only minor improvements in energy fluxes at both sites and regional scales. In the future, coupling this enhanced crop module with the Weather Research and Forecasting model will better our understanding of the interconnections between winter wheat croplands and climate. Key Points: Phenological scheme, vernalization process, and key parameters associated with winter wheat photosynthesis and carbon allocations were developed and optimizedThe developed parameterization of winter wheat was evaluated in both site‐level and regional simulations in the North China PlainSimulations of winter‐wheat phenological development, yield, carbon, and energy fluxes were significantly improved [ABSTRACT FROM AUTHOR]

Winter survival is an essential trait for winter wheat (Triticum aestivum L.) cultivars grown in high latitude regions such as Eastern Canada. Indoor studies have identified that copy number variation of genes influencing freezing is an essential component. Although Canadian winter wheat is predominantly grown in Eastern Canada, the extent to which allele variation in freezing tolerance genes affects winter survival in this region remains unknown, as there are presently no studies characterizing such variation in Canadian winter wheat germplasm. In this study, we characterized a panel 415 Canadian winter wheat cultivars for haplotype diversity of the Frost Resistance-2 (Fr-A2) locus and copy number variation of Vernalization-A1 (Vrn-A1) and C-repeat binding factors-A14 (CBF-A14). Additionally, this study evaluates each gene's effect on winter survival across two locations and 2 years. We found that a combination of Vrn-A1 copy number and Fr-A2 haplotype accounted for 67.38% of the genotypic variance. Most of the cultivars tested (77.3%) carry the allele combination of three copies of Vrn-A1 and the Fr-A2-T haplotype, which was associated with the best winter survival. Interestingly, copy number of Vrn-A1 did not significantly affect heading time, therefore, selecting for higher copy number of Vrn-A1 would not affect maturity. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of low-temperature (LT) stress during the jointing stage on three most representative wheat varieties in the Huang-Huai-Hai region: "Shannong 38" (a robust winter wheat variety), "Jimai 22" (a semi-winter wheat variety), and "Zhenmai 12" (a weak winter wheat variety). The objective was to explain the sensitivity and change thresholds of various physiological and yield indicators of three winter wheat varieties to low temperatures during the jointing stage and to construct an index for the grading of LT disasters during the jointing stage using principal component analysis. Controlled environment experiments were conducted using an artificial climate chamber during the jointing stage of winter wheat. Five daily minimum temperature treatments were applied, namely (T1, −6 °C); (T2, −3 °C); (T3, 0 °C); (T4, 3 °C); (T5, 6 °C); and control (CK, 8 °C). The duration of treatments was divided into three levels: (D1: 2 days), (D2: 4 days), and (D3: 6 days). It was found that the photosynthetic parameters and chlorophyll content showed a decreasing trend with the increase in the degree of LT stress. The activities of protective enzymes and endogenous hormones increased during the early stages of LT stress or at relatively high temperatures. However, they decreased significantly with an increase in LT stress. Among the varieties, "Zhenmai 12" exhibited a yield reduction rate exceeding 10% under 3 °C LT stress for more than 4 days and a yield reduction rate exceeding 20% under 0 °C LT stress for more than 6 days. "Jimai 22" showed a yield reduction rate exceeding 10% under 3 °C LT stress lasting more than 2 days, and a yield reduction rate exceeding 20% under −3 °C LT stress lasting more than 4 days. "Shannong 38" experienced a yield reduction rate exceeding 10% under 0 °C LT stress lasting more than 4 days and a yield reduction rate exceeding 20% under −6 °C LT stress lasting more than 6 days. Principal component analysis (PCA) conducted on all trait indicators of the three winter wheat varieties revealed that "Zhenmai 12" experienced mild LT stress at 6 °C for 2 days, moderate LT stress at 0 °C for 6 days, and severe LT stress at −3 °C for 6 days. "Jimai 22" experienced mild LT stress under 6 °C for 6 days, moderate LT stress under 0 °C for 4 days, and severe LT stress under −6 °C for 2 days. "Shannong 38" experienced mild LT stress under 3 °C for 4 days, moderate LT stress under 0 °C for 4 days, and severe LT stress under −6 °C for 6 days. [ABSTRACT FROM AUTHOR]

A timely and comprehensive understanding of winter wheat maturity is crucial for deploying large-scale harvesters within a region, ensuring timely winter wheat harvesting, and maintaining grain quality. Winter wheat maturity prediction is limited by two key issues: accurate extraction of wheat planting areas and effective maturity prediction methods. The primary aim of this study is to propose a method for predicting winter wheat maturity. The method comprises three parts: (i) winter wheat planting area extraction via phenological characteristics across multiple growth stages; (ii) extraction of winter wheat maturity features via vegetation indices (VIs, such as NDVI, NDRE, NDII1, and NDII2) and box plot analysis; and (iii) winter wheat maturity data prediction via the selected VIs. The key findings of this work are as follows: (i) Combining multispectral remote sensing data from the winter wheat jointing-filling and maturity-harvest stages can provide high-precision extraction of winter wheat planting areas (OA = 95.67%, PA = 91.67%, UA = 99.64%, and Kappa = 0.9133). (ii) The proposed method can offer the highest accuracy in predicting maturity at the winter wheat flowering stage (R2 = 0.802, RMSE = 1.56 days), aiding in a timely and comprehensive understanding of winter wheat maturity and in deploying large-scale harvesters within the region. (iii) The study's validation was only conducted for winter wheat maturity prediction in the North China Plain wheat production area, and the accuracy of harvesting progress information extraction for other regions' wheat still requires further testing. The method proposed in this study can provide accurate predictions of winter wheat maturity, helping agricultural management departments adopt information-based measures to improve the efficiency of monitoring winter wheat maturation and harvesting, thus promoting the efficiency of precision agricultural operations and informatization efforts. [ABSTRACT FROM AUTHOR]

At the major vernalization locus 'Vrn-D1', the spring allele, Vrn-D1a, and two winter alleles, Vrn-D1b and vrn-D1, have been identified in wheat. We conducted field trials to determine the effects of alleles on growth and yield-related traits, using near-isogenic lines developed in the genetic background of spring type wheat cultivars, 'Abukumawase' and 'Asakazekomugi', both of which carry the Vrn-D1a allele. Although maturity date of three alleles was same, the panicle development occurred earlier in the following order of genotype: Vrn-D1a > Vrn-D1b > vrn-D1. There was a significant difference in panicle development even between two winter type alleles vrn-D1 and Vrn-D1b. Grain yield and the spikelet number per spike of the original spring type cultivars were lower than those of the winter type NILs. In addition, while the young panicle development of the tillers in the spring type cultivars was found to be two weeks to one month later in the tillers than that in the main stem, young panicle development of the main stem and tillers in the winter type NILs were almost identical. Hence, winter type wheat bearing vrn-D1 which exhibit later panicle development than that bearing Vrn-D1b, was elucidated to might be more useful especially in areas with high risk of frost damage. Spring type wheat had a lower sink capacity and grain yield, meanwhile that was considered to prevent severe frost damage by allowing late-developed tillers to survive. [ABSTRACT FROM AUTHOR]

Background: Powdery mildew (caused by Blumeria graminis f. sp. tritici (Bgt)) and leaf rust (caused by Puccinia triticina (Pt)) are prevalent diseases in wheat (Triticum aestivum L.) production. Thinopyrum ponticum (2n = 10x = 70, EeEeEbEbExExStStStSt) contains genes that confer high levels of resistance to these diseases. Results: An elite wheat-Th. ponticum disomic substitution line, DS5Ag(5D), was developed in the Bainong Aikang 58 (AK58) background. The line was assessed using genomic in situ hybridization (GISH), oligo-nucleotide probe multiplex (ONPM) fluorescence in situ hybridization (FISH), and molecular markers. Twenty eight chromosome-specific molecular markers were identified for the alien chromosome, and 22 of them were co-dominant. Additionally, SNP markers from the wheat 660 K SNP chip were utilized to confirm chromosome identification and they provide molecular tools for tagging the chromosome in concern. The substitution line demonstrated high levels of resistance to powdery mildew throughout its growth period and to leaf rust at the adult stage. Based on the resistance evaluation of five F5 populations between the substitution lines and wheat genotypes with different levels of sensitivity to the two diseases. Results showed that the resistance genes located on 5Ag confered stable resistance against both diseases across different backgrounds. Resistance spectrum analysis combined with diagnostic marker detection of known resistance genes of Th. ponticum revealed that 5Ag contained two novel genes, Pm5Ag and Lr5Ag, which conferred resistance to powdery mildew and leaf rust, respectively. Conclusions: In this study, a novel wheat-Th. ponticum disomic substitution line DS5Ag(5D) was successfully developed. The Th. ponticum chromosome 5Ag contain new resistance genes for powdery mildew and leaf rust. Chromosomic—specific molecular markers were generated and they can be used to track the 5Ag chromosome fragments. Consequently, this study provides new elite germplasm resources and molecular markers to facilitate the breeding of wheat varieties that is resistant to powdery mildew and leaf rust. [ABSTRACT FROM AUTHOR]

Methods: Cultivar characterization indicated that the increase in yield was negatively affected by spike number and positively affected by the number of kernels per spike before the 2000s and kernel weight after the 2000s. Field trials were conducted across two ecological zones over two consecutive wheatgrowing seasons. The results showed that genetic gains in grain yield, spike number, and kernel weight during 1955 to 2021 were 0.629%, 0.574%, and 0.332% year-1 on a relative basis or 39.12 kg ha-1, 24,350 hm-2, and 0.15 g year-1 on an absolute basis, respectively. However, the increase in the kernel number per spike was not significant. Moreover, cultivar replacement explained 25.6%, 12.8%, and 37.5% of the total variance in grain yield, spike number, and kernel weight, respectively. In summary, during the initial grain-filling stage, wheat cultivar replacement led to the shortening of grain-filling duration and rapid grain-filling rate. However, a longer active grain-filling duration was produced by prolonged durations of rapid and late grain-filling. Additionally, the experimental year had a greater effect on the kernel number, which explained 53.2% of the total variance. Ultimately, modern wheat cultivars had a greater kernel weight. Results: Although the increase in kernel weight has affected grain yield during cultivar replacements in the Haihe Plain, the potential for further yield increase through kernel weight enhancement alone is limited. Consequently, future breeding efforts and cultivation practices should focus on improving spike traits and canopy architecture to enhance productivity. [ABSTRACT FROM AUTHOR]

Summary: Investigating plant responses to climate change is key to develop suitable adaptation strategies. However, whether changes in land management can alleviate increasing drought threats to crops in the future is still unclear.We conducted a management × drought experiment with winter wheat (Triticum aestivum L.) to study plant water and vegetative traits in response to drought and management (conventional vs organic farming, with intensive vs conservation tillage). Water traits (root water uptake pattern, stem metaxylem area, leaf water potential, stomatal conductance) and vegetative traits (plant height, leaf area, leaf Chl content) were considered simultaneously to characterise the variability of multiple traits in a trait space, using principal component analysis.Management could not alleviate the drought impacts on plant water traits as it mainly affected vegetative traits, with yields ultimately being affected by both management and drought. Trait spaces were clearly separated between organic and conventional management as well as between drought and control conditions. Moreover, changes in trait space triggered by management and drought were independent from each other.Neither organic management nor conservation tillage eased drought impacts on winter wheat. Thus, our study raised concerns about the effectiveness of these management options as adaptation strategies to climate change. [ABSTRACT FROM AUTHOR]

AbstractCurrent agricultural production systems face challenges of poor economic returns, soil fatigue and negative environmental outcomes from excess use of nitrogenous fertilizers, especially in wheat production under middle gangetic plains. To overcome these challenges, the current study was conducted to optimize nitrogen management in different wheat genotypes with precision nitrogen management tools and approaches. The field experiment was laid out in split-plot design, with three genotypes assigned to the main plot and six nitrogen management practices to the sub-plot. The soil of the experimental field was sandy loam in texture, with low levels of organic carbon and available nitrogen, and medium levels of available phosphorus and potassium. Results revealed that the HD-2967 genotype outperformed others in terms of growth, grain yield (4.7 and 4.81 t ha−1), gross return (1417.41 and 1505.48 US$ ha−1), net return (953.43 and 1019.76 US$ ha−1), and B-C ratio (2.04 and 2.08) in 2015-16 and 2016-17, respectively. Among the nitrogen management practices, application of 150 kg N ha−1 in three equal splits demonstrated improved crop growth, grain yield (4.7 and 4.81 t ha−1), and economic returns (gross return, 1500.40 and 1607.65 US$ ha−1, net return, 1025.40 and 1110.38 US$ ha−1 and B: C ratio, 2.17 and 2.23) in 2015-16 and 2016-17, respectively. However, it resulted in higher nitrogen losses. Green seeker guided N application significantly reduced apparent nitrogen losses compared to all other nitrogen applied treatments. These findings provide valuable insights for optimizing wheat production by selecting appropriate genotypes and implementing precision nitrogen management techniques to enhance yield, profitability, and environmental sustainability. [ABSTRACT FROM AUTHOR]

Seeding rate recommendations for wheat (Triticum aestivum L.) are often 150–450 seeds m−2. However, we hypothesize that wheat grown with high resource availability (i.e., fertility and moisture) can maximize yield under considerably lower rates. Our objectives were to explore winter wheat response to low populations under high resource availability using yield‐contest fields as a case study. A factorial experiment evaluated four wheat varieties (i.e., Joe, WB‐Grainfield, Langin, and LCS Revere) exposed to five seeding rates (50, 100, 150, 200, and 250 seeds m−2) during five seasons in commercial wheat fields managed by yield‐contest winning producers near Leoti, KS. Fields were silt‐loam soils with high available water‐holding capacity, long‐term history of manure application with non‐limiting fertility, and adopted a sorghum [Sorghum bicolor (L.) Moench]–fallow–wheat rotation. Plant density ranged from 26 to 341 plants m−2 and yield ranged from 3.2 to 6.8 Mg ha−1. Water use efficiency of 19.5 kg ha−1 mm−1 suggested no management limitations to yield. Quadratic models portrayed the grain yield–plant density relation well, with 95% of the maximum yield reached at 68 to 91 plants m−2 for crops sown at the optimum date (4 out of 5 years), and at 312 plants m−2 for a late‐sown crop. Greater fall temperature accumulation reduced the relative yield between the maximum and minimum seeding rates. There was no variety × plant density interaction and Langin was the most consistent yielding variety across environments. Optimum plant density for winter wheat in environments with high resource availability may be considerably lower than current recommendations. [ABSTRACT FROM AUTHOR]

Studying the influence of the host plant genotype on the spectral reflectance of crops infected by a pathogen is one of the key directions in the development of precision methods for monitoring the phytosanitary state of wheat agrocenoses. The purpose of this research was to study the influence of varietal factors and disease development on the spectral characteristics of winter wheat varieties of different susceptibility to diseases during the growing seasons of 2021, 2022 and 2023. The studied winter wheat crops were represented by three varieties differing in susceptibility to phytopathogens: Grom, Svarog and Bezostaya 100. Over three years of research, a clear and pronounced influence of the varietal factor on the spectral characteristics of winter wheat crops was observed, which in most cases manifested itself as an immunological reaction of specific varieties to the influence of pathogen development. The nature of the influence of the pathogenic background and the spectral characteristics of winter wheat crops were determined by the complex interaction of the development of individual diseases under the conditions of a particular year of research. A uniform and clear division of the spectral characteristics of winter wheat according to the intensity of the disease was recorded only at a level of pathogen development of more than 5%. Moreover, this gradation was most clearly manifested in the spectral channels of the near-infrared range and at a wavelength of 720 nm. [ABSTRACT FROM AUTHOR]

To effectively reveal the disaster-causing mechanism between water stress and yield loss under different drought combinations during multiple growth periods of winter wheat, based on biennial wheat drought experiments, a crop growth analysis method was used to quantitatively identify and assess wheat yield loss sensitivity. The results showed that there was a significant negative correlation between the total dry matter relative growth rate (RGR) of wheat and the daily average degree of drought stress. The average determination coefficients of logarithmic fitting for 2017 and 2018 were 0.7935 and 0.7683, respectively. Wheat dry matter accumulation differed under the different drought combination scenarios. The yield loss sensitivity response relationship between the decrease in the RGR of wheat dry matter (relative to no drought stress) and the daily average degree of drought stress could be quantitatively identified by an S-shaped curve, and the 2017 and 2018 average coefficients of determination R2 were 0.859 and 0.849, respectively. Mild drought stress at the tillering stage stimulates adaptability and has little effect on yield. The soil water content (SWC) can be controlled to 65–75% of the field water holding capacity; the SWC at the jointing and booting stage can be controlled to be higher than the field water holding capacity of 55%. The SWC was maintained at a level higher than 75% of the field water holding capacity during the heading and flowering stages and the grain-filling and milky stages to achieve a harmonization of yields and water savings. In addition, during the production process, continuous severe drought during the jointing and booting stage and the heading and flowering stage should be avoided. This study elucidates the response relationship between drought intensity and drought-induced losses from the perspective of physical genesis, provides effective irrigation guidance for regional wheat planting, lays the foundation for the construction of quantitative agricultural drought loss risk curves, and provides technical support for predicting the trend of yield losses in wheat under different drought stresses. [ABSTRACT FROM AUTHOR]

Hybrid breeding can increase the competitiveness of wheat (Triticum aestivum L.) in Sub-Saharan Africa by fostering more public-private partnerships and promoting investment by the private sector. The benefit of hybrid wheat cultivars in South Africa has previously been demonstrated but due to the high cost of hybrid seed production, hybrid breeding has not received significant attention in the past decade. Considering the renewed commitment of the private sector to establish wheat as a hybrid crop globally, coupled with significant research investment into enhancement of outcrossing of wheat, hybrid wheat breeding in Southern and Eastern Africa should be revisited. Our study aimed to identify genetically distinct germplasm groups in spring wheat that would be useful in the establishment of heterotic pools targeting this region. Multi-environment yield testing of a large panel of F1 test hybrids, generated using global elite germplasm, was carried out between 2019 and 2020 in Argentina, Africa, Europe, and Australia. We observed significant genotype by environment interactions within our testing network, confirming the distinctiveness of African trial sites. Relatively high additive genetic variance was observed highlighting the contribution of parental genotypes to the grain yield of test hybrids. We explored the genetic architecture of these parents and the genetic factors underlying the value of parents appear to be associated with their genetic subgroup, with positive marker effects distributed throughout the genome. In testcrosses, elite germplasm from the International Maize and Wheat Improvement Center (CIMMYT) appear to be complementary to the genetically distinct germplasm bred in South Africa. The feasibility of achieving genetic gain via heterotic pool establishment and divergence, and by extension the viability of hybrid cultivars in Sub-Saharan Africa, is supported by the results of our study. [ABSTRACT FROM AUTHOR]

Wheat leaf disease prevention and treatment requires an accurate and rapid classification of wheat leaf diseases and their extent. Using healthy wheat, leaf rust, crown, root rot, and wheat loose smut as research objects, this study proposes a deep learning-based technique for classifying wheat leaf diseases. A collaborative generative adversarial network is used as an image imputation in the proposed methodology, allowing a generator and discriminator network to properly estimate the missing data in the dataset using the residual method. It is used to improve feature extraction in wheat leaf images. The major contribution of this study is to use a pre-trained deep learning convolutional neural network architecture as a foundation to improve and construct an automated tool for wheat leaf disease image categorization. To classify wheat leaf diseases, a modification to the Residual Network with 50 layers (ResNet50) is being suggested. The ′Conv′, ′Batch Normaliz′, and ′Activation Leaky Relu′ layers were added as part of this modification. These layers are inserted into the ResNet50 architecture for accurate feature extraction and discrimination. Extensive tests are carried out to evaluate the proposed model's performance on photos from a large wheat disease classification dataset. The suggested approach outperforms ResNet50, InceptionV3, and DenseNet, according to the experimental findings. The suggested method achieves the greatest identification accuracy of 98.44%. These discoveries might aid in the accurate detection and categorization of wheat leaf diseases. [ABSTRACT FROM AUTHOR]

This study was conducted in controlled environmental conditions to systematically evaluate multi-traits responses of winter wheat (Triticum aestivumL.) genotypes to different salinity levels. Responses were assessed at the germination to early seedling stage (Experiment 1). Seeds of different genotypes (n=292) were subjected to three salinity levels (0 [control], 60, and 120 mM NaCl). Principal Component Analysis (PCA) revealed that among studied traits seedling vigor index (SVI) contributed more towards the diverse response of genotypes to salinity stress. Based on SVI, eight contrasting genotypes assumed to be tolerant (Gage, Guymon, MTS0531, and Tascosa) and susceptible (CO04W320, Carson, TX04M410211) were selected for further physio-biochemical evaluation at the booting stage (Experiment 2) and to monitor grain yield. Higher level of salinity (120 mM NaCl) exposure at the booting stage increased thylakoid membrane damage, lipid peroxidation, sugars, proline, and protein while decreasing photosynthesis, chlorophyll index, starch, and grain yield. Based on grain yield, the assumed magnitude of the genotypic response shown in Experiment 1 was not analogous in Experiment 2. This indicates the necessity of individual screening of genotypes at different sensitive growth stages for identifying true salinity-tolerant and susceptible genotypes at a particular growth stage. However, based on higher grain yield and its least percentage reduction under higher salinity, Guymon and TX04M410211were identified as tolerant, andGage and CO04W320 as susceptible at the booting stage, and their biparental population can be used to identify genomic regions for booting stage-specific salinity response. [ABSTRACT FROM AUTHOR]

Spring wheat (Triticum aestivum L.) remains an important alternative to winter wheat cultivation at Northern latitudes due to high risk of overwintering or delayed sowing of winter wheat. We studied nine major agronomic traits in a set of 299 spring wheat genotypes in trials across 12-year-site combinations in Lithuania, Latvia, Estonia, and Norway for three consecutive years. The dataset analyzed here consisted of previously published phenotypic data collected in 2021 and 2022, supplemented with additional phenotypic data from the 2023 field season collected in this study. We combined these phenotypic datasets with previously published genotypic data generated using a 25K single nucleotide polymorphism (SNP) array that yielded 18,467 markers with a minor allele frequency above 0.05. Analysis of these datasets via genome-wide association study revealed 18 consistent quantitative trait loci (QTL) replicated in two or more trials that explained more than 5% of phenotypic variance for plant height, grain protein content, thousand kernel weight, or heading date. The most consistent markers across the tested environments were detected for plant height, thousand kernel weight, and days to heading in eight, five, and six trials, respectively. No beneficial effect of the semi-dwarfing alleles Rht-B1b and Rht-D1b on grain yield performance was observed across the 12 tested trials. Moreover, the cultivars carrying these alleles were low yielding in general. Based on principal component analysis, wheat genotypes developed in the Northern European region clustered separately from those developed at the southern latitudes, and markers associated with the clustering were identified. Important phenotypic traits, such as grain yield, days to heading, grain protein content, and thousand kernel weight were associated with this clustering of the genotype sets. Interestingly, despite being adapted to the Nordic environment, genotypes in the Northern set demonstrated lower grain yield performance across all tested environments. The results indicate that spring wheat germplasm harbors valuable QTL/alleles, and the identified traitmarker associations might be useful in improving Nordic-Baltic spring wheat germplasm under global warming conditions. [ABSTRACT FROM AUTHOR]

Rapidly obtaining the chlorophyll content of crop leaves is of great significance for timely diagnosis of crop health and effective field management. Multispectral imagery obtained from unmanned aerial vehicles (UAV) is being used to remotely sense the SPAD (Soil and Plant Analyzer Development) values of wheat crops. However, existing research has not yet fully considered the impact of different growth stages and crop populations on the accuracy of SPAD estimation. In this study, 300 materials from winter wheat natural populations in Xinjiang, collected between 2020 to 2022, were analyzed. UAV multispectral images were obtained in the experimental area, and vegetation indices were extracted to analyze the correlation between the selected vegetation indices and SPAD values. The input variables for the model were screened, and a support vector machine (SVM) model was constructed to estimate SPAD values during the heading, flowering, and filling stages under different water stresses. The aim was to provide a method for the rapid acquisition of winter wheat SPAD values. The results showed that the SPAD values under normal irrigation were higher than those under water restriction. Multiple vegetation indices were significantly correlated with SPAD values. In the prediction model construction of SPAD, the different models had high estimation accuracy under both normal irrigation and water limitation treatments, with correlation coefficients of predicted and measured values under normal irrigation in different environments the value of r from 0.59 to 0.81 and RMSE from 2.15 to 11.64, compared to RE from 0.10% to 1.00%; and under drought stress in different environments, correlation coefficients of predicted and measured values of r was 0.69--0.79, RMSE was 2.30--12.94, and RE was 0.10%--1.30%. This study demonstrated that the optimal combination of feature selection methods and machine learning algorithms can lead to a more accurate estimation of winter wheat SPAD values. In summary, the SVM model based on UAV multispectral images can rapidly and accurately estimate winter wheat SPAD value. [ABSTRACT FROM AUTHOR]

A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action, yet its impact on wheat (Triticum aestivum L.) production remains unclear. We use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to 2018. After calibrating parameters with the extended Fourier Amplitude Sensitivity Test (EFAST) and the generalized likelihood uncertainty estimation (GLUE) method, the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more accurately. We found that the aerosol negatively impacted wheat biomass by 21.87% and yield by 22.48% from 2006 to 2018, and the biomass effects from planting to anthesis were more significant compared to anthesis to maturity. Due to the strict clean air action, under all-sky conditions, the surface solar shortwave radiation (SSR) in 2018 increased by about 7.08% over 2006-2013 during the wheat growing seasons. As a result of the improvement of crop photosynthesis, winter wheat biomass and yield increased by an average of 5.46% and 2.9%, respectively. Our findings show that crop carbon uptake and yield will benefit from the clean air action in China, helping to ensure national food and health security. [ABSTRACT FROM AUTHOR]

Reliable and spatially explicit information on global crop yield has paramount implications for food security and agricultural sustainability. However, most previous yield estimates are either coarse-resolution in both space and time or are based on limited studied areas. Here, we developed a transferable approach to estimate 4 km global wheat yields and provide the related product from 1982 to 2020 (GlobalWheatYield4km). A spectra–phenology integration method was firstly proposed to identify spatial distributions of spring and winter wheat, followed by choosing the optimal yield prediction model at 4 km grid scale, with openly accessible data, including subnational-level census data covering ~11,000 political units. Finally, the optimal models were transferred at both spatial and temporal scales to obtain a consistent yield dataset product. The results showed that GlobalWheatYield4km captured 82% of yield variations with an RMSE of 619.8 kg/ha, indicating good temporal consistency (r and nRMSE ranging from 0.4 to 0.8 and 13.7% to 37.9%) with the observed yields across all subnational regions covering 40 years. In addition, our dataset generally had a higher accuracy (R2 = 0.71) as compared with the Spatial Production Allocation Model (SPAM) (R2 = 0.49). The method proposed for the global yield estimate would be applicable to other crops and other areas during other years, and our GlobalWheatYield4km dataset will play important roles in agro-ecosystem modeling and climate impact and adaptation assessment over larger spatial extents. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi form mutualistic relationships with the majority of land plants and are an important part of the soil microbial community in natural and agricultural ecosystems. These fungi promote water and nutrient acquisition by their host plant and regulate the allocation of photosynthetic carbon to soil. Both crop variety and environment affect naturally occurring mycorrhizal abundance in roots, but the relative importance of those factors for mycorrhization is largely unknown. In a field study covering a large pedoclimatic gradient across four European sites, we (i) compared the abundance of AM fungi in the roots of 10 modern winter wheat (Triticum aestivum L.) varieties, (ii) evaluated the relative importance of variety and site for the variability in root colonization by AM fungi and (iii) tested the relationship between mycorrhizal abundance and grain yield. Root colonization by arbuscules and hyphae ranged from 10% to 59% and 20% to 91%, respectively, across all samples and varied by 8% and 18%, respectively, among varieties when averaged across sites. Variance decomposition analysis revealed a 10 times higher importance of site than variety for AM fungal root colonization. Specifically, we found the highest mycorrhizal abundance on the site with the most arid conditions and the lowest on the sites with low soil pH and high nutrient availability. Despite the low variability in mycorrhizal abundance among varieties, there were significant differences in both arbuscular and hyphal root colonization. However, this did not translate into an increase in yield as no significant relationships between mycorrhizal abundance at flowering and grain yield were detected. The consistent differences between wheat varieties in root colonization by AM fungi across European field sites underline that genetic drivers of mycorrhization are to some extent independent of the site. This highlights the relevance of breeding practices to shape a wheat variety's capacity for mycorrhizal symbiosis across a range of environmental conditions. [ABSTRACT FROM AUTHOR]

The GSK3/SHAGGY‐like kinase plays critical roles in plant development and response to stress, but its specific function remains largely unknown in wheat (Triticum aestivum L.). In this study, we investigated the function of TaGSK3, a GSK3/SHAGGY‐like kinase, in wheat development and response to stress. Our findings demonstrated that TaGSK3 mutants had significant effects on wheat seedling development and brassinosteroid (BR) signalling. Quadruple and quintuple mutants showed amplified BR signalling, promoting seedling development, while a sextuple mutant displayed severe developmental defects but still responded to exogenous BR signals, indicating redundancy and non‐BR‐related functions of TaGSK3. A gain‐of‐function mutation in TaGSK3‐3D disrupted BR signalling, resulting in compact and dwarf plant architecture. Notably, this mutation conferred significant drought and heat stress resistance of wheat, and enhanced heat tolerance independent of BR signalling, unlike knock‐down mutants. Further research revealed that this mutation maintains a higher relative water content by regulating stomatal‐mediated water loss and maintains a lower ROS level to reduces cell damage, enabling better growth under stress. Our study provides comprehensive insights into the role of TaGSK3 in wheat development, stress response, and BR signal transduction, offering potential for modifying TaGSK3 to improve agronomic traits and enhance stress resistance in wheat. Summary statement: Our findings elucidated the redundant role of TaGSK3 in wheat brassinosteroid (BR) signalling and developmental phenotypes, as well as its unique ability to enhance heat resistance independently of the BR signal. [ABSTRACT FROM AUTHOR]

Bainong sterility (BNS) is a thermo‐sensitive genic male sterile wheat line, characterised by anther fertility transformation in response to low temperature (LT) stress during meiosis, the failure of vacuole decomposition and the absence of starch accumulation in sterile bicellular pollen. Our study demonstrates that the late microspore (LM) stage marks the transition from the anther growth to anther maturation phase, characterised by the changes in anther structure, carbohydrate metabolism and the main transport pathway of sucrose (Suc). Fructan is a main storage polysaccharide in wheat anther, and its synthesis and remobilisation are crucial for anther development. Moreover, the process of pollen amylogenesis and the fate of the large vacuole in pollen are closely intertwined with fructan synthesis and remobilisation. LT disrupts the normal physiological metabolism of BNS anthers during meiosis, particularly affecting carbohydrate metabolism, thus determining the fate of male gametophytes and pollen abortion. Disruption of fructan synthesis and remobilisation regulation serves as a decisive event that results in anther abortion. Sterile pollen exhibits common traits of pollen starvation and impaired starch accumulation due to the inhibition of apoplastic transport starting from the LM stage, which is regulated by cell wall invertase TaIVR1 and Suc transporter TaSUT1. Summary statement: The manuscript provides new insight into the role of carbohydrate metabolism in regulating anther development and the molecular mechanisms underlying pollen abortion in a thermo‐sensitive genic male sterile winter wheat line under low temperature during meiosis. [ABSTRACT FROM AUTHOR]

Several short‐term studies have investigated 4R (right source, rate, time, and place) N management for dryland wheat (Triticum aestivum L.) production and profitability, but few long‐term studies exist in the United States or abroad. This study evaluated long‐term impacts of several aspects of 4R N management on dryland hard red wheat yield, protein, and return to N. Experiments were conducted at Nephi and Blue Creek, UT, during 1995–2007. Fourteen N treatments evaluated performance of starter fertilizer, fall applications of anhydrous ammonia (AA) with and without nitrapyrin (AA‐Nitrapyrin and AA, respectively), and several split applications in the fall and spring. Across years, winter wheat required N to increase yield, protein, and returns at both sites. Applying 56 kg N ha−1 as AA in the fall usually produced the best return to N compared to other N treatments. Starter N (6 kg N ha−1) at fall planting rarely increased yield, protein, or returns at either site. Across both sites, nitrapyrin increased mean annual yield by 0.6 Mg ha−1 and mean return to N by $150 ha−1. Spring application of N was rarely required and only increased yield in 13% of the years. Results indicate that nitrapryin is often needed with fall AA applications to optimize yield and returns and that starter N or extra N in the spring are rarely economical in dryland wheat in Utah and possibly the greater Intermountain West. Further, N rate had the most influence among 4Rs on wheat production and should be the focus of future efforts to improve 4R stewardship. Core Ideas: Few long‐term studies have compared various 4R (right source, rate, time, and place) nitrogen aspects for dryland wheat–fallow systems.Across 13 years, fall fertilizer N was needed to optimize production and economics in dryland wheat–fallow system.Starter N and spring N applications rarely improved wheat yield, protein, or return to N.Nitrapyrin added to anhydrous ammonia increased mean annual yield by 0.6 Mg ha−1 and mean return to N by $150 ha−1.N rate had the most influence among 4Rs on wheat production and should be focus of future 4R stewardship efforts. [ABSTRACT FROM AUTHOR]

Propineb is a widely used protective fungicide in farmland. To investigate the effects of propineb on cadmium (Cd) accumulation and the physiological characteristics of wheat seedlings under Cd stress, we performed a hydroponic experiment with artificially added Cd. The results indicated that the application of propineb leads to a decrease in Cd accumulation in the shoots of wheat. During the low-Cd treatment experiment, propineb caused Cd to transfer from the soluble component to the cell wall. In terms of the chemical morphological distribution of Cd in wheat seedlings, propineb reduced the proportions of ethanol extracted state and deionized water extracted state, whereas the proportions of acetic acid extracted state and hydrochloric acid extracted state increased. The photosynthetic rate of wheat seedlings significantly increased, but there was no significant effect on the chlorophyll content. Foliar application of propineb increased the O2− clearance rate and hydrogen peroxide content in the wheat. However, the catalase content decreased. This study indicates that the application of propineb could decrease Cd accumulation in wheat seedlings and partially improve the physiological functions of plants. This study provides useful information for studying the effects of pesticides on Cd accumulation in crops and the physiological characteristics of Cd stress. [ABSTRACT FROM AUTHOR]

Background: Wheat landraces are considered a valuable source of genetic diversity for breeding programs. It is useful to evaluate the genetic diversity in breeding studies such as marker-assisted selection (MAS), genome-wide association studies (GWAS), and genomic selection. In addition, constructing a core germplasm set that represents the genetic diversity of the entire variety set is of great significance for the efficient conservation and utilization of wheat landrace germplasms. Results: To understand the genetic diversity in wheat landrace, 2,023 accessions in the Jiangsu Provincial Crop Germplasm Resource Bank were used to explore the molecular diversity and population structure using the Illumina 15 K single nucleotide polymorphism (SNP) chip. These accessions were divided into five subpopulations based on population structure, principal coordinate and kinship analysis. A significant variation was found within and among the subpopulations based on the molecular variance analysis (AMOVA). Subpopulation 3 showed more genetic variability based on the different allelic patterns (Na, Ne and I). The M strategy as implemented in MStratv 4.1 software was used to construct the representative core collection. A core collection with a total of 311 accessions (15.37%) was selected from the entire landrace germplasm based on genotype and 12 different phenotypic traits. Compared to the initial landrace collections, the core collection displayed higher gene diversity (0.31) and polymorphism information content (PIC) (0.25), and represented almost all phenotypic variation. Conclusions: A core collection comprising 311 accessions containing 100% of the genetic variation in the initial population was developed. This collection provides a germplasm base for effective management, conservation, and utilization of the variation in the original set. [ABSTRACT FROM AUTHOR]

Genetic resistance is the most economical and efficient way to reduce production losses brought on by diseases. Plant breeders continuously incorporate new, dependable sources into their breeding materials to continue developing disease-resistant genotypes. Fourteen certified wheat (Triticum aestivum L.) cultivar (Bahawalpur-2000, NIFA-Bathor08, Fareed-2006, Haider-2002, Imdad-2005, Lasani-2008, Marvi-2000, Moomal-2000, Manther-2003, Pirsabak-2006, Iqbal-2000, Pirsabak-2004, Shahkar-2013, and Wafaq-2002) seeds from the Nuclear Institute for Food and Agriculture (NIFA) and National Agriculture Research Center (NARC) were grown in pots. DNA obtained from fresh leaves of the wheat cultivars were screened for leaf rust resistance genes (i.e. Lr-51, Lr-47, Lr-46, Lr-37, Lr-36, Lr-35, Lr-34, Lr-28, Lr-25, Lr-19, Lr-13, Lr-9, and Lr-1 using PCR. Results showed that the Lr-47 gene was present in nine wheat cultivars, Lr-1 and Lr-28 in eight, Lr-5, Lr-9, and Lr-13 in three, and Lr-19 and Lr-37 in one cultivar. In the selected wheat cultivars, the resistance genes Lr-25, Lr-35, Lr-36, and Lr-46 were not observed. This study suggests cultivating wheat varieties Haider-2002, Iqbal-2000, Lasani-2008, Manther-2003, Pirsbak-2004, Pirsbak-2006, Shahkar-2013, and Wafaq-2002 for high level of resistance to rust and protection against high production losses. In future studies, phenotypic data alongside genotypic screening will improve the assessment of leaf rust resistance in wheat cultivars, leading to a better understanding of their disease resistance profiles. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), mainly incited by Fusarium graminearum, has caused great losses in grain yield and quality of wheat globally. Fhb7, major gene from 7E chromosome of Thinopyrum ponticum, confers broad resistance to multiple Fusarium species in wheat and has recently been cloned and identified as encoding a glutathione S-transferase (GST). CRISPRHowever, some recent reports raised doubt about whether GSTis the causal gene of Fhb7. To resolve the discrepancy and validate the gene function of GST in wheat, we phenotyped Flib7 near-isogenic lines (Jimai22-Fhb7 versus Jimai22) and GSToverexpressed lines for FHB resistance. Jimai22-Fhb7 showed significantly higher FHB resistance with a lower percentage of symptomatic spikelets, Fusaritun-damaged kernels, and deoxynivalenol content than susceptible Jimai22 in three experiments. All the positive GST transgenic lines driven by either the maize ubiquitin promoter or its native promoter with high gene expression in the wheat cultivar 'Fielder' showed high FHB resistance. Only one inaize ubiquitin promoter-driven transgenic line showed low GST expression and similar susceptibility to Fielder, suggesting that high GST expression confers Fhb7 resistance to FHB. Knockout of GST in the Jimai22-Fhb7 line using CRISPRHowever, Cas9-based gene editing showed significantly higher FHB susceptibility compared with the nonedited control plants. Therefore, we confirmed GST as the causal gene of Fhb7 for FHB resistance. Considering its major effect on FHB resistance, pyramiding Fhb7 with other quantitative trait loci has a great potential to create highly FHB -resistant wheat cultivars. [ABSTRACT FROM AUTHOR]