Winter Wheat Cultivars Research Articles

GA071518‐16E39: A new adapted soft red winter wheat cultivar to Georgia and the US Southeast Region

AbstractThe production of soft red winter wheat (SRWW) (Triticum aestivum L.) in the US southeast (SE) region is important. However, wheat production faces many challenges including many stresses resulting in substantial losses in yield and quality. To address these challenges, developing new cultivars with high yield potential with resistance to major pests in the region and good quality is warranted. The SRWW breeding programs ate the University of Georgia (UGA) and the regional institutions including the Southern Universities GRAINS (SUNGRAINS) programs aims to solve these problems. The release of ‘GA071518‐16E39’ (Reg. no. CV‐1210, PI 698826) SRWW in 2019, is among many adapted cultivars developed and released by the UGA College of Agricultural and Environmental Sciences. GA071518‐16E39 has broad adaptation to the US SE region, but specifically well fit to the Georgia environments. It is a high yielding cultivar with excellent resistance to most dominant diseases including leaf (caused by Puccinia triticina Erikss.) and stripe (caused by P. striiformis Westend.) rusts, Soil‐borne wheat mosaic virus, and Hessian fly insect [Mayetiola destructor (Say)] including major prevalent biotypes (B, C, O, and L) in the region. GA071518‐16E39 is moderately resistant to powdery mildew (caused by Erisyphe graminis) and moderate susceptible to Fusarium head blight (caused by Fusarium graminearum Schwabe) which is reflected in relatively lower levels of disease severity and Deoxynivalenol toxin. GA071518‐16E39 has excellent grain volume weight and milling and baking quality as a SRWW.

QTL analysis in the Mianmai 902×Taichang 29 RIL population reveals the genetic basis for the high-yield of wheat cultivars Mianmai 902 in terms of spike and plant architecture

Spike-related traits and plant height (PH) are greatly associated with wheat yield. Identification of stable quantitative trait loci (QTL) for these traits is crucial for understanding the genetic basis for yield and their further application in breeding. In this study, QTL analysis for spikelet number per spike (SNS), spike length (SL), spike compactness (SC) and PH was performed using a recombinant inbred line (RIL) population derived from a cross between wheat cultivars Mianmai902 (MM902) and Taichang29 (TC29). Thirteen stably expressed QTLs were identified, and the most favorable alleles were contributed by MM902. The mjaor QTL, QSNS-MT.cib-2D, QSL-MT.cib-2D, QSC-MT.cib-2D, QSC-MT.cib-6 A, QPH-MT.cib-4B and QPH-MT.cib-4D, were repeatedly detected in multiple environments and explained 5.77-47.11% of the phenotypic variations. By employing the Kompetitive Allele Specific PCR markers, the most major QTLs were successfully validated in multiple populations derived from different genetic backgrounds. Moreover, the individual and pyramiding effects of major QTLs on SNS, SL, SC, PH, grain number per spike (GNS) and thousand-grain weight (TGW) were investigated and their potential utilization value in breeding was showcased. Ppd-D1 was predicted as the candidate for QSNS/SL/SC/PH-MT.cib-2D, and MM902 carried the Ppd-D1d allele. Ppd-D1d is rare in Chinese winter wheat cultivars and may be an elite alternative allele of the Ppd-D1a allele. In summary, these QTLs revealed the genetic basis of the spike-related traits and PH of MM902, which partially contributed to the high yield of MM902 and have application potential in wheat breeding by optimizing spike morphology and PH to improve yield.

Adaptation and Grain Yield Stability Analysis of Winter Wheat Cultivars with and Without Fungicides Treatment from National Variety Trials in Sweden

Adaptation and Grain Yield Stability Analysis of Winter Wheat Cultivars with and Without Fungicides Treatment from National Variety Trials in Sweden

Registration of ‘GA09436‐16LE12’: A new soft red winter wheat cultivar adapted to the US southeast region

Registration of ‘GA09436‐16LE12’: A new soft red winter wheat cultivar adapted to the US southeast region

Winter wheat cultivar post‐harvest effects: Varieties differ in residue management requirements and effect on yield of next crop

AbstractThis study investigated the potential of different wheat varieties to influence the performance of the subsequent wheat crop. In fall 2021, a single variety of winter wheat (cv. Norwest Tandem) was planted into standing wheat stubble in plots that were previously planted to five winter wheat varieties. At harvest, yield was significantly affected by the variety that had been planted in each plot during the first year of the trial. Specifically, wheat following the variety Pritchett yielded approximately 12% more than wheat following the variety Bobtail. While planting the second crop, residue from the winter wheat variety Norwest Duet caused the no‐till plot drill to plug (accumulate large amounts of soil and crop residue in front of openers) far more than residue from the other varieties. This indicates that varieties differ in their residue management requirements. These differences could be exploited to best fit different agricultural practices. This study highlights the potential importance of varietal effects that persist in the field after the field is harvested. However, more work is needed to understand varietal differences in residue management requirements and varietal effects of the successive crop before they can be fully leveraged in wheat breeding and genetics, wheat agronomy, variety testing programs, and eventually the producer's field.

Genetic Analysis of Stripe Rust Resistance in the Chinese Wheat Cultivar Luomai 163.

Stripe or yellow rust (YR) caused by Puccinia striiformis tritici (Pst) is an important foliar disease affecting wheat production globally. Resistant varieties are the most economically and environmentally effective way to manage this disease. The common winter wheat (Triticum aestivum L.) cultivar Luomai 163 exhibited resistance to the Pst races CYR32 and CYR33 at the seedling stage and showed a high level of adult plant resistance in the field. To understand the genetic basis of YR resistance in this cultivar, 142 F5 recombinant inbred lines (RILs) derived from cross Apav#1 × LM163 and both parents were genotyped with the 16K SNP array and bulked segregant analysis sequencing. The analysis detected a major gene, YrLM163, at the seedling stage associated with the 1BL.1RS translocation. Additionally, three genes for resistance at the adult plant stage were detected on chromosome arms 1BL (Lr46/Yr29/Pm39/Sr58), 6BS, and 6BL in Luomai 163, whereas Apav#1 contributed resistance at a quantitative trait locus (QTL) on 2BL. These QTL explained YR disease severity variations ranging from 6.9 to 54.8%. The kompetitive allele-specific PCR (KASP) markers KASP-2BL, KASP-6BS, and KASP-6BL for the three novel loci QYr.hzau-2BL, QYr.hzau-6BS, and QYr.hzau-6BL were developed and validated. QYr.hzau-1BL, QYr.hzau-2BL, and QYr.hzau-6BS showed varying degrees of resistance to YR when present individually or in combination based on genotype and phenotype analysis of a panel of 570 wheat accessions. Six RILs combining resistance alleles of all QTL, showing higher resistance to YR in the field than Luomai 163 with disease severities of 10.7 to 16.0%, are important germplasm resources for breeding programs to develop YR-resistant wheat varieties with good agronomic traits.

Effects of Melatonin Pre- and Post-Drought Treatment on Oxidative Stress Markers and Expression of Proline-Related Transcripts in Young Wheat Plants.

Wheat can tolerate a mild water deficit, but prolonged drought causes a number of detrimental physiological changes resulting in a substantial decrease in productivity. The present study evaluates the potential of the natural plant growth regulator melatonin to alleviate the negative effects of moderate drought in two Bulgarian winter wheat cultivars at the early vegetative stage. Melatonin doses of 75 µM were root-supplemented 24 h before or after the stress period. The levels of several biometric parameters, osmolyte content and stress indicators as well as the expression of genes coding for key enzymes of the proline biosynthesis pathway were analyzed in leaves at the end of the drought stress and after two and four days of recovery. Applied alone, melatonin did not exert significant effects on most of the monitored parameters. Water deprivation negatively affected seedlings' fresh weight and water content and increased the stress markers and osmolyte levels. These were accompanied by a high accumulation of TaP5CS and TaP5CR transcripts coding for the enzymes Δ-pyrroline-5-carboxylate synthase and Δ-pyrroline-5-carboxylate reductase, respectively. The effect of melatonin in reducing drought stress was similar whether applied before or after exposure, though slightly more effective when used as a pre-treatment.

Analysis of the Physiological Parameters of Cold Resistance in Core Winter and Spring Wheat Cultivars

We selected 46 core winter–spring wheat cultivars from China’s main wheat-producing areas as experimental materials to clarify the differences in the physiological parameters of their cold resistance and provide a theoretical basis and high-quality germplasm for cold resistance breeding. We investigated differences in their cold resistance under field conditions for two consecutive years, and determined the physiological parameters of the cold resistance, yield, and quality indicators of different winter–spring wheat cultivars. Our results showed that the cold resistance of winter wheat cultivars was higher than that of spring wheat cultivars. The chlorophyll (Chl), soluble sugar (SS), soluble protein (SP), and free proline (Pro) contents of different winter–spring wheat cultivars were positively correlated with cold resistance, and malondialdehyde (MDA) content was negatively correlated with cold resistance. The five physiological parameters can be used as physiological indicators for the breeding of cold-resistant cultivars. The cold resistance, yield, and quality indicators of different spring and winter wheat cultivars were comprehensively evaluated by using the average membership value and comprehensive score. It was found that the average membership value and comprehensive score of winter wheat cultivars were higher than those of spring wheat cultivars. Through classification using the K-means method, the cold-resistant, high-yield, and high-quality cultivars were screened out, namely, Jimai23 (JM23), Jimai44 (JM44), Shannong57 (SN57), and Jinmai 919 (JM919).

Differentiating Growth Patterns in Winter Wheat Cultivars via Unmanned Aerial Vehicle Imaging

Wheat is one of the most widely grown cereal crops, serving as a key factor in sustaining the nutritional and food balance in numerous countries. The use of non-contact methods for wheat monitoring allows for the rapid diagnosis of vegetation density, crop growth, and the presence of weeds and diseases in the investigated fields. This study aims to assess the potential for differentiating growth patterns in winter wheat cultivars by examining them with two unmanned aerial vehicles (UAVs), the Mavic 2 Pro and Phantom 4 Pro, equipped with a multispectral camera from the MAPIR™ brand. Based on an experimental study conducted in the Southern Dobruja region (Bulgaria), vegetation reflectance indices, such as the Normalized-Difference Vegetation Index (NDVI), Soil-Adjusted Vegetation Index (SAVI), and Enhanced Vegetation Index 2 (EVI2), were generated, and a database was created to track their changing trends. The obtained results showed that the values of the NDVI, EVI2, and SAVI can be used to predict the productive potential of wheat, but only after accounting for the meteorological conditions of the respective growing season. The proposed methodology provides accurate results in small areas, with a resolution of 0.40 cm/pixel when flying at an altitude of 12 m and 2.3 cm/pixel when flying at an altitude of 100 m. The achieved precision in small and ultra-small agricultural areas, at a width of 1.2 m, will help wheat breeders conduct precise diagnostics of individual wheat varieties.

Distribution of Hybrid Necrosis Genes in Genotypes of Winter Soft wheat (<i>Triticum aestivum</i> L.) Cultivars of English Selection

The genetic diversity of 15 cultivars of winter soft wheat of English selection has been studied. It was found that 11 (73.3%) of the cultivars studied carried the Ne2 gene (genotype ne1ne1Ne2Ne2), and four cultivars (26.7%) were free of hybrid necrosis genes (genotype ne1ne1ne2ne2). The Ne1 gene was not detected. Cultivars with the Ne2 gene differed in allele strength. Moderate (m) allele was identified in four cultivars, and moderately strong (ms) allele was identified in the genotypes of seven cultivars.

Characterization of Bila Tserkva winter common wheat cultivars with respect to marker loci

Aim. We studied special features of the sample of Bila Tserkva winter common wheat cultivars with respect to storage protein loci and some disease resistance genes. Methods. To identify alleles at gliadin and high-molecular-weight glutenin loci, acid polyacrylamide gel electrophoresis and SDS-electrophoresis of grain proteins were carried out. Alleles of markers for the disease resistance genes Lr34, Tsn1, and TDF_076_2D were identified using PCR. Results. The composition and frequencies of alleles at the Gli-1, Glu-1, and Gli-A3 loci were studied in samples of Bila Tserkva cultivars released before 2011 and after 2010. For the latter group of cultivars, alleles of the disease resistance gene markers were identified. We observed a significant increase in the frequency of the allele Gli-A1x(9) and a decrease in the frequency of Gli-A1c, as well as a tendency for an increase in the frequency of Gli-A3c. In the total sample of Bila Tserkva cultivars, nonrandom associations of pairs of certain storage protein alleles were revealed. Conclusions. The group of Bila Tserkva cultivars is similar to the previously studied groups of the Central Forest Steppe of Ukraine with respect to allele set and frequencies of the main prolamin loci, but differs in the frequencies of the disease resistance genes. A special feature of the group of Bila Tserkva cultivars is a high frequency of the allele c at the minor locus Gli-A3, as well as the allele association Gli-A1x Gli-B1l Gli-A3c.

Comparative Analysis of Phytohormone Biosynthesis Genes Responses to Long-Term High Light in Tolerant and Sensitive Wheat Cultivars.

Phytohormones are vital for developmental processes, from organ initiation to senescence, and are key regulators of growth, development, and photosynthesis. In natural environments, plants often experience high light (HL) intensities coupled with elevated temperatures, which pose significant threats to agricultural production. However, the response of phytohormone-related genes to long-term HL exposure remains unclear. Here, we examined the expression levels of genes involved in the biosynthesis of ten phytohormones, including gibberellins, cytokinins, salicylic acid, jasmonic acid, abscisic acid, brassinosteroids, indole-3-acetic acid, strigolactones, nitric oxide, and ethylene, in two winter wheat cultivars, Xiaoyan 54 (XY54, HL tolerant) and Jing 411 (J411, HL sensitive), when transferred from low light to HL for 2-8 days. Under HL, most genes were markedly inhibited, while a few, such as TaGA2ox, TaAAO3, TaLOG1, and TaPAL2, were induced in both varieties. Interestingly, TaGA2ox2 and TaAAO3 expression positively correlated with sugar content but negatively with chlorophyll content and TaAGP expression. In addition, we observed that both varieties experienced a sharp decline in chlorophyll content and photosynthesis performance after prolonged HL exposure, with J411 showing significantly more sensitivity than XY54. Hierarchical clustering analysis classified the phytohormone genes into the following three groups: Group 1 included six genes highly expressed in J411; Group 2 contained 25 genes drastically suppressed by HL in both varieties; and Group 3 contained three genes highly expressed in XY54. Notably, abscisic acid (ABA), and jasmonic acid (JA) biosynthesis genes and their content were significantly higher, while gibberellins (GA) content was lower in XY54 than J411. Together, these results suggest that the differential expression and content of GA, ABA, and JA play crucial roles in the contrasting responses of tolerant and sensitive wheat cultivars to leaf senescence induced by long-term HL. This study enhances our understanding of the mechanisms underlying HL tolerance in wheat and can guide the development of more resilient wheat varieties.

Winter Wheat Experiments to Optimize Sowing Dates and Densities in a High-Yielding Environment in New Zealand: Field Experiments and AgMIP-Wheat Multi-Model Simulations

This paper describes the data set that was used to test the accuracy of twenty-nine crop models in simulating the effect of changing sowing dates and sowing densities on wheat productivity for a high-yielding environment in New Zealand. The data includes one winter wheat cultivar (Wakanui) grown during six consecutive years, from 2012-2013 to 2017-2018, at two farms located in Leeston and Wakanui in Canterbury, New Zealand. The simulations were carried out in the framework of the Agricultural Model Intercomparison and Improvement Project for wheat (AgMIP-Wheat). Data include local daily weather data, soil profile characteristics and initial conditions, crop measurements at maturity (grain, stem, chaff and leaf dry weight, ear number and grain number, grain unit dry weight), and at stem elongation and anthesis (total above ground dry biomass, leaf number per stem and leaf area index). Several in-season measurements of the normalized difference vegetation index (NDVI) and the fraction of intercepted photosynthetically active radiation (FIPAR) are also available. The crop model simulations include both daily in-season and end-of-season results from twenty-nine wheat models.

Fine mapping of stem rust resistance derived from soft red winter wheat cultivar AGS2000 to an NLR gene cluster on chromosome 6D

The Puccinia graminis f. sp. tritici (Pgt) Ug99-emerging virulent races present a major challenge to global wheat production. To meet present and future needs, new sources of resistance must be found. Identification of markers that allow tracking of resistance genes is needed for deployment strategies to combat highly virulent pathogen races. Field evaluation of a DH population located a QTL for stem rust (Sr) resistance, QSr.nc-6D from the breeding line MD01W28-08-11 to the distal region of chromosome arm 6DS where Sr resistance genes Sr42, SrCad, and SrTmp have been identified. A locus for seedling resistance to Pgt race TTKSK was identified in a DH population and an RIL population derived from the cross AGS2000 × LA95135. The resistant cultivar AGS2000 is in the pedigree of MD01W28-08-11 and our results suggest that it is the source of Sr resistance in this breeding line. We exploited published markers and exome capture data to enrich marker density in a 10 Mb region flanking QSr.nc-6D. Our fine mapping in heterozygous inbred families identified three markers co-segregating with resistance and delimited QSr.nc-6D to a 1.3 Mb region. We further exploited information from other genome assemblies and identified collinear regions of 6DS harboring clusters of NLR genes. Evaluation of KASP assays corresponding to our co-segregating SNP suggests that they can be used to track this Sr resistance in breeding programs. However, our results also underscore the challenges posed in identifying genes underlying resistance in such complex regions in the absence of genome sequence from the resistant genotypes.

Changes in phosphorus-related performance attributes of dryland winter wheat cultivars released between the 1940s and 2010s in Shaanxi Province, China.

Water and nutrients are two main determinants of wheat yield, which are vital for maintaining high crop yields. In the present study, the effects of water and phosphate fertilization on wheat yield, photosynthetic parameters, water productivity and phosphate use efficiency were investigated. Five dryland wheat cultivars from the 1940s to the 2010s that are widely cultivated in Shaanxi Province, China, were used. Experiments were conducted from 2019 to 2022 using two irrigation levels (normal rainfall and no precipitation after the reviving stage) and two phosphorus application levels (0 and 100 kg ha-1). Compared with old cultivars ('Mazha'), the grain yield of modern cultivars ('Changhan 58') was 89.24% higher and was closely correlated with chlorophyll index, leaf area index, photosynthetic rate and tillers. With the replacement of cultivars, the phosphorus content, water potential and phosphatase activity of wheat leaves increased. Considering water-phosphorus interactions, the water use efficiency and phosphorus use efficiency of wheat showed a significant positive correlation. Our findings indicate that modern wheat cultivars are more responsive to phosphorus. Further analysis revealed that modern varieties have evolved two phosphorus absorption strategies in response to phosphorus deficiency - namely, the formation of a phosphorus supply source, which may result in larger numbers of green organs; and an increase in phosphorus sinks, which tended to activation and transport of plant phosphorus. Our results may thus contribute to water conservation, increased yields and the development of strategies for efficient phosphorus fertilization. © 2024 Society of Chemical Industry.

Penalties in Granule Size Distribution and Viscosity Parameters of Starch Caused by Lodging in Winter Wheat

Granule size distribution of wheat starch is an important characteristic that could affect the functionality of wheat (Triticum aestivum L.) products. Lodging is a major limiting factor for wheat production. Few studies have been conducted to clarify how lodging influences the granule size distribution and viscosity parameters of starch in wheat grains. Two growing seasons, two high-yield winter wheat cultivars, and five artificial lodging treatments were imposed. The results indicated that lodging significantly reduced the content of starch and increased that of protein. Additionally, lodging caused a marked drop in both starch and protein yields. The relative loss of grain yield, starch yield, harvest index, and protein yield all differed remarkably among lodging treatments with a ranking of L2 > L1 > L4 > L3. Lodging also led to a reduction in the proportion (both by volume and by surface area) of B-type granules and a corresponding increase in that of A-type granules, and the more serious the lodging degree, the greater effect on the changes in these proportions. The smaller starch granules predominated in number, even though their collective contribution to the overall volume is was relatively minor. Meanwhile, it was found that the peak viscosity, hold viscosity, final viscosity, breakdown viscosity, and rebound value of wheat starch were significantly decreased by lodging. Correlation analysis showed that the peak and final viscosities were negatively correlated with volume percentages of A-type starch granules, but were positively correlated with B-type granules. This indicates that B-type granules have higher peak and final viscosities compared with A-type granules in wheat kernels. Lodging can reduce the proportion of B-type starch granules, and thus reduce the peak and the final viscosity in wheat grain.

Seedling resistance of winter and spring bread wheat cultivars to <i>Pyrenophora tritici-repentis</i>

Seedling resistance of winter and spring bread wheat cultivars to <i>Pyrenophora tritici-repentis</i>

Testing the efficacy of a newly released fungicide, Sphaerex, for control of Fusarium Head Blight in wheat

Fusarium head blight (FHB) is a destructive disease of wheat and other small-grain cereals. FHB causes reduction in crop yield due to pre-mature bleaching of spikes. Additionally, it deteriorates the crop quality due to the production of mycotoxins. An integrated management strategy is needed to effectively manage this disease. One of the most important strategies in the FHB management toolbox is chemical control. Fungicides start losing their efficacy over time due to the development of fungicide resistance in the pathogens. This necessitates the development and testing of new fungicides with multiple active ingredients or modes of action. In this 3-year study, we evaluated the effectiveness of a new fungicide with multiple active ingredients, Sphaerex (a proprietary mix of metconazole and prothioconazole) in an FHB-susceptible soft red winter wheat cultivar, Shirley in the eastern United States. Sphaerex provided significantly better control over untreated plots for FHB Incidence, FHB Severity, and DON content across all three years. The level of control of FHB and DON by Sphaerex was found to be similar to that provided by other standard FHB fungicides. The yield of the fungicide-treated plots was statistically similar to that of the untreated plots.

Wheat yield and grain-filling characteristics due to cultivar replacement in the Haihe Plain in China.

The Haihe Plain plays an important role in wheat production and food security in China and has experienced continuous cultivar replacement since the 1950s.This study assessed the evolution of the yield and grain-filling characteristics of the main winter wheat cultivars in the Haihe Plain over the last seven decades (1950s to date). 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. 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.

Multigenerational Drought Reveals a Stable Wheat Seed Fungal Community

Wheat ( Triticum spp.) is a staple food crop, providing a fifth of the world's protein and caloric needs. Our research examines the impact of multigeneration postflowering drought stress on the wheat seed endophytic fungal community. Understanding how wheat seed fungal communities respond to drought stress over several generations can improve our knowledge of legacy drought stress. In this article, we aim to identify seed-associated fungi that play critical roles within the wheat seed under drought stress conditions. We examined the endophytic seed fungal communities of three winter wheat cultivars, Catawba, Shirley, and USG 3640. Moderate drought was imposed on a subset of plants immediately after flowering, with plants relieved from drought stress after 1 week. Seeds harvested from generation 1 were planted for a second generation of drought experiments. When examining the postflowering drought impact on wheat physiology, drought-exposed plants consistently exhibited lower daily transpiration rates, chlorophyll-a values, and seed yield compared with control plants, indicating that drought implementation was successful. Internal transcribed spacer 1 metabarcoding revealed that wheat seed fungal community species richness decreased during postanthesis drought stress across both generations. We also observed that generation accounted for variation in fungal species richness and community structure, independent of drought treatment. The most abundant taxa recovered across all cultivars, treatments, and generations included Cladosporium, Penicillium, Alternaria, and Epicoccum. These results support our hypothesis that postanthesis drought shapes the wheat seed fungal community.