Triticum Aestivum Research Articles

Coordination of miR319-TaPCF8 with TaSPL14 orchestrates auxin signaling and biosynthesis to regulate plant height in common wheat.

Wheat culms, comprising four to six internodes, are critically involved in determining plant height and lodging resistance, essential factors for field performance and regional adaptability. This study revealed the regulatory function of miR319 in common wheat plant height. Repression of tae-miR319 through short tandem target mimics (STTM) caused an increased plant height, while overexpression (OE) of tae-miR319 had the opposite effect. Overexpressing a miR319-resistant target gene TaPCF8 (rTaPCF8), increased plant height. TaPCF8 acted as a transcription repressor of downstream genes TaIAAs, which interact physically with TaSPL14. The significant differences of indole-3-acetic acid (IAA) contents indicate the involvement of auxin pathway in miR319-mediated plant height regulation. Finally, we identified two TaPCF8 haplotypes in global wheat collections. TaPCF8-5A-Hap2, as per association and evolution examinations, was subjected to strong substantial selection throughout wheat breeding. This haplotype, associated with shorter plant height, aligns with global breeding requirements. Consequently, in high-yield wheat breeding, we proposed a potential molecular marker for marker-assisted selection (MAS). Our findings offer fresh perspectives into the molecular mechanisms that underlie the miR319-TaPCF8 module's regulation of plant height by orchestrating auxin signaling and biosynthesis in wheat.

Arsenic and zinc concentrations in wheat grains under soil zinc application and arsenic‐contaminated irrigation

AbstractAbove‐permissible levels of arsenic (As) in irrigation water lead to toxic levels in wheat grains, increasing health risks for humans. In this study, two zinc (Zn)‐biofortified wheat (Triticum aestivum L.) cultivars (Akbar‐2019 and Zincol‐2016) were grown in pots with two Zn application rates (0 and 8 mg Zn kg−1) and three levels of As in irrigation water (distilled‐water control, 100 and 1000 µg As L−1). Irrigation with As‐contaminated water decreased dry matter yields, concentrations of grain phosphorus (P) and Zn, and estimated daily intake (EDI) of Zn. Conversely, it increased grain As concentration and As EDI. Soil Zn application mitigated the negative effects of As on dry matter yields of both cultivars while simultaneously enhancing grain Zn concentration and Zn EDI. On average, Zn application increased grain Zn concentration by 114% compared to no Zn application. Additionally, Zn application decreased grain As concentration at all As levels. In conclusion, this study suggests that applying Zn to Zn‐biofortified wheat irrigated with As‐contaminated water can mitigate the toxic effects of As on wheat. It increase Zn concentration and decrease As concentration in wheat grains, which is vital for enhancing grain quality for human consumption.

Physiological and antioxidant responses of synthetic hexaploid wheat germplasm under drought

BackgroundAs a result of the world population and climate change impact increases (especially in arid environments), there is a critical need for high-yield, drought-tolerant wheat. Synthetic hexaploid wheat derived lines (SHW-DL), were created artificially by crossing different durum wheat cultivars (AABB) with accessions of Aegilops tauschii (DD), a beneficial source of new genes for common bread wheat (Triticum aestivum L). Here, we studied the response of a panel of 91 SHW-DL for drought tolerance based on physiological, antioxidant enzyme activities, and drought tolerance indices.ResultsA wide range of variation and high values of heritability observed for grain yield, physiological and antioxidant traits indicating that the SHW-DL panel constitutes a valuable gene source for drought tolerance improvement of wheat. Despite decreases in grain yield (YLD), leaf area index (LAI), and relative water content (RWC) an increase in the content of malondialdehyde (MDA) was observed. Moreover, drought streass increased the antioxidant enzyme activities of ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD), and also photosynthetic pigments, proline (Pro), and MDA content. With higher values of grain yield, physiological and biochemical traits such as photosynthetic pigments, and RWC, and lower content of MDA, and peroxidase (H2O2) activity, SHW-DL performed better compared to common wheat lines under water stress conditions.ConclusionsDifferent responses to water stress within the germplasm and between synthetic and common wheat suggest that selection for adaptive and suitable genotypes is possible for drought tolerance in synthetic wheat germplasm. Genotypes 54, 98, 102, 105, 122, 124, 143, 159, 196, and 198 were identified to be directly used in breeding programs or indirectly by crossing them with other wheat germplasm collections.

The characteristic analysis of TaTDF1 reveals its function related to male sterility in wheat (Triticum aestivum L.)

BackgroundThe male sterile lines are an important foundation for heterosis utilization in wheat (Triticum aestivum L.). Thereinto, pollen development is one of the indispensable processes of wheat reproductive development, and its fertility plays an important role in wheat heterosis utilization, and are usually influencing by genes. However, these key genes and their regulatory networks during pollen abortion are poorly understood in wheat.ResultsDEFECTIVE IN TAPETAL DEVELOPMENT AND FUNCTION 1 (TDF1) is a member of the R2R3-MYB family and has been shown to be essential for early tapetal layer development and pollen grain fertility in rice (Oryza sativa L.) and Arabidopsis thaliana. In order to clarify the function of TDF1 in wheat anthers development, we used OsTDF1 gene as a reference sequence and homologous cloned wheat TaTDF1 gene. TaTDF1 is localized in the nucleus. The average bolting time of Arabidopsis thaliana overexpressed strain (TaTDF1-OE) was 33 d, and its anther could be colored normally by Alexander staining solution, showing red. The dominant Mosaic suppression silence-line (TaTDF1-EAR) was blue-green in color, and the anthers were shrimpy and thin. The TaTDF1 interacting protein (TaMAP65) was confirmed using Yeast Two-Hybrid Assay (Y2H) and Bimolecular-Fluorescence Complementation (BiFC) experiments. The results showed that downregulated expression of TaTDF1 and TaMAP65 could cause anthers to be smaller and shrunken, leading to pollen abortion in TaTDF1 wheat plants induced by virus-induced gene-silencing technology. The expression pattern of TaTDF1 was influenced by TaMAP65.ConclusionsThus, systematically revealing the regulatory mechanism of wheat TaTDF1 during anther and pollen grain development may provide new information on the molecular mechanism of pollen abortion in wheat.

N Fertilizer in Combination with Straw Improves Soil Physicochemical Properties and Crop Productivity in Sub-Humid, Drought-Prone Areas

Straw returning may be an efficient strategy to maintain agricultural sustainability. However, which straw returning strategy can effectively improve soil properties and crop yield remain unclear. A five-year (2011–2016) field experiment in sub-humid, drought-prone areas of northwestern China with uneven rainfall distribution and irrigation was conducted to evaluate the effects of nitrogen fertilizer without straw mulching (CK), with regular straw mulching (LSM), and with ammoniated straw plowing (ALSP) on soil water, soil aggregates, soil organic carbon (SOC), total nitrogen (TN), and water use efficiency (WUE) in an annual winter wheat (Triticum aestivum L.)–summer maize (Zea mays L.) rotation system. The results demonstrate that ALSP had a greater soil water content than CK in the 0–60 cm soil layer. ALSP also had substantially more soil water than LSM in the 0–100 cm layer during the wet year (2011–2012) and two dry years (2014–2015 and 2015–2016). In the normal years (2012–2013 and 2013–2014), the soil water content in ALSP was significantly lower than in LSM in the 0–20 cm soil layer. ALSP was better able to alleviate soil drought in dry years and excessive humidity in wet years. Compared to CK, SOC in the 0–20 cm soil layer in 2016 increased by 8.3% in LSM and 11.7% in ALSP, and TN in the upper soil increased by 6.6% in LSM and 10.1% in ALSP. The equivalent wheat yield and WUE increased in ALSP by 15.6% and 17.5%, respectively, relative to CK, and by 6.79% and 5.97%, respectively, relative to LSM. Thus, we concluded that plowing ammoniated straw with N fertilization is a promising strategy for improving soil fertility and crop productivity in winter wheat–summer maize rotation systems in the sub-humid, drought-prone areas of northwestern China.

Comparison of population photosynthesis characteristics and grain yield of wheat under various sowing dates and seeding rates

AbstractThis study investigated the effects of sowing dates and seeding rates on photosynthetic characteristics and grain yield in wheat (Triticum aestivum L.). A field experiment was conducted with three sowing dates—early sowing date (SD‐E), normal sowing date (SD‐N), and delay sowing date (SD‐D)—and three seeding rates—90 low seeding rate (SR‐L), 108 moderate seeding rate (SR‐M), and high seeding rate 126 kg ha−1 (SR‐H). The results revealed that the grain yield at SR‐L in the SD‐E regime, SR‐M in the SD‐N regime, and SR‐H in the SD‐D regime was increased by 7.48%–9.93%, 14.1%–16.7%, and 19.0%–41.6%, respectively, compared to other combinations under the same sowing date. Consistent with the yield performance, the aboveground biomass accumulation, nonstructural carbohydrates (NSC) accumulation in stems, and NSC remobilization amount from anthesis to maturity were the highest at SR‐L in the SD‐E, at SR‐M in the SD‐N, or at SR‐H in the SD‐D regime, among other treatment combinations. Improved canopy photosynthetic characteristics (i.e., leaf area index, leaf photosynthetic rate, canopy photosynthetically active radiation interception rate, and radiation use efficiency) were also observed at the SR‐M in the SD‐N or at SR‐H in the SD‐D regime. Collectively, a suitable sowing date combined with an optimum seeding rate could enhance grain yield, and increasing the seeding rate could mitigate the yield loss when sowing was delayed by optimizing traits photosynthesis in wheat.

Enhanced Resilience to Salt Stress: An Integrated Approach Addressing Physiochemical Attributes of Wheat (Triticum aestivum L.)

Enhanced Resilience to Salt Stress: An Integrated Approach Addressing Physiochemical Attributes of Wheat (Triticum aestivum L.)

Ozone priming enhanced low temperature tolerance of wheat (Triticum aestivum L.) based on physiological, biochemical and transcriptional analyses.

Low temperature significantly inhibits the plant growth in wheat (Triticum aestivum L.), prompting the exploration of effective strategies to mitigate low temperature stress. Several priming methods enhance low temperature stress tolerant, however, the role of ozone priming remains unclear in wheat. Here we found ozone priming alleviated low temperature stress in wheat. Transcriptome analysis showed that ozone priming positively modulated 'photosynthesis-antenna proteins' pathway in wheat under low temperature. Which was confirmed by the results of the ozone-primed plants had higher trapped energy flux and electron transport flux per reaction, and less damage to chloroplasts than non-primed plants under low temperature. Ozone priming also mitigated the overstimulation of glutathione metabolism and induced the accumulation of total ascorbic acid and glutathione, maintained redox homeostasis in wheat under low temperature. Moreover, gene expressions and enzyme activities in glycolysis pathways were upregulated in ozone priming comparing with non-priming after the low temperature stress. Furthermore, exogenous antibiotics significantly increased low temperature tolerance, which further proved that the inhibition of ribosome biogenesis by ozone priming was involved in low temperature tolerance in wheat. In conclusion, ozone priming enhanced wheat low temperature tolerance through promoting light-harvesting capacity, redox homeostasis, and carbohydrate metabolism, as well as inhibiting ribosome biogenesis.

Stomatal penetration: the cornerstone of plant resistance to the fungal pathogen Zymoseptoria tritici

BackgroundSeptoria tritici blotch (STB), caused by the foliar fungus Zymoseptoria tritici, is one of the most damaging disease of wheat in Europe. Genetic resistance against this fungus relies on different types of resistance from non-host resistance (NHR) and host species specific resistance (HSSR) to host resistance mediated by quantitative trait loci (QTLs) or major resistance genes (Stb). Characterizing the diversity of theses resistances is of great importance for breeding wheat cultivars with efficient and durable resistance. While the functional mechanisms underlying these resistance types are not well understood, increasing piece of evidence suggest that fungus stomatal penetration and early establishment in the apoplast are both crucial for the outcome of some interactions between Z. tritici and plants. To validate and extend these previous observations, we conducted quantitative comparative phenotypical and cytological analyses of the infection process corresponding to 22 different interactions between plant species and Z. tritici isolates. These interactions included four major bread wheat Stb genes, four bread wheat accessions with contrasting quantitative resistance, two species resistant to Z. tritici isolates from bread wheat (HSSR) and four plant species resistant to all Z. tritici isolates (NHR).ResultsInfiltration of Z. tritici spores into plant leaves allowed the partial bypass of all bread wheat resistances and durum wheat resistance, but not resistances from other plants species. Quantitative comparative cytological analysis showed that in the non-grass plant Nicotiana benthamiana, Z. tritici was stopped before stomatal penetration. By contrast, in all resistant grass plants, Z. tritici was stopped, at least partly, during stomatal penetration. The intensity of this early plant control process varied depending on resistance types, quantitative resistances being the least effective. These analyses also demonstrated that Stb-mediated resistances, HSSR and NHR, but not quantitative resistances, relied on the strong growth inhibition of the few Z. tritici penetrating hyphae at their entry point in the sub-stomatal cavity.ConclusionsIn addition to furnishing a robust quantitative cytological assessment system, our study uncovered three stopping patterns of Z. tritici by plant resistances. Stomatal resistance was found important for most resistances to Z. tritici, independently of its type (Stb, HSSR, NHR). These results provided a basis for the functional analysis of wheat resistance to Z. tritici and its improvement.

Effects of atmospheric CO2 concentration on transpiration and leaf elongation responses to drought in Triticum aestivum, Lolium perenne and Festuca arundinacea.

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

Antibiosis in small grain cereals against the rose-grain aphid, Metopolophium dirhodum (Hemiptera: Aphididae)

Resistance against aphids is an integrated pest management tactic that enhances the economic and environmental sustainability of cereal production. The aim of our study was to assess the degree of antibiosis against Metopolophium dirhodum (Walker) (Hemiptera: Aphididae), one of the most important cereal aphids in temperate regions, in two lines of small grain cereals bred in the Crop Research Institute (CRI) of Prague: spring wheat, Triticum aestivum L. cv. ‘Rufia’, and germplasm of durum wheat, Triticum turgidum ssp. durum (Desf.) van Slageren ‘TTD40363’, under controlled laboratory conditions. Resistant spring wheat cultivar (‘Libertina’) and highly susceptible spring barley (Hordeum vulgare L. cv. ‘Sebastian’) were used for reference. The responses of M. dirhodum to each line and population growth projections were determined according to the age-stage, two-sex life table theory. We found that Rufia was susceptible and TTD40363 was rather resistant to M. dirhodum. The projected population sizes after 35 days were ~ 41,000 individuals in spring wheat Rufia and ~ 12,000 in durum wheat TTD40363, which is within the range delimited by the reference cultivars (4,000 in the highly resistant spring wheat Libertina and 77,500 in highly susceptible spring barley Sebastian). This study provides new data on small grain cereal resistance to aphids. An age-stage, two-sex life table approach was used to assess resistance to aphids on durum wheat and barley for the first time.

The efficiency of Bacillus subtilis and Thuja orientalis leaves extracts as biocontrol agents of damping off in wheat (Triticum aestivum)

The efficiency of Bacillus subtilis and Thuja orientalis leaves extracts as biocontrol agents of damping off in wheat (Triticum aestivum)

Genetic variability for end-use quality proteins in a collection of bread wheat Mediterranean landraces

Genetic variability for end-use quality proteins in a collection of bread wheat Mediterranean landraces

The Impact of Salinity on the Productivity and Quality of Durum and bread Wheat

Salinity poses a significant challenge to the quality and productivity of crops. In the primary wheat cultivation areas worldwide, salinity negatively affects wheat growth, yield, and quality. To address this issue, the development of tolerant wheat varieties through selective breeding techniques is essential. The aim of this study was to assess the effects of salinity on grain yield, protein content, and thousand-kernel weight (TKW) among 55 different varieties and accessions of bread and durum wheat. The findings revealed that the application of salt treatment (100 mM NaCl solution) resulted in reduced growth and yield production in 45 bread and durum wheat varieties. However, 6 durum wheat varieties, 3 durum wheat accessions, and 1 common wheat accession showed insignificant susceptibility to salinity. These included Chryssodur from Greece, Saragolla, Silur, and Dakter from Italy, Sculptur from France, Karim from Tunisia, Algeria 70-2 from Algeria, Ethiopia 201 and Ethiopia 229 from Ethiopia, and the Morocco 85 accession of bread wheat from Morocco. The decline in grain yield could be attributed to salinity, which led to a decrease in photosynthetic capacity, resulting in reduced starch synthesis and accumulation in the grain. Furthermore, the study demonstrated that winter wheat exhibited greater tolerance to salt stress compared to spring wheat, and durum wheat displayed higher tolerance than common wheat. Additionally, salt accumulation was found to increase protein content in five varieties and one accession of durum wheat. This variation may be linked to the relatively stable nitrogen metabolism under salt stress, contributing to higher protein concentrations. TKW also decreased in all 10 varieties and accessions, irrespective of the species.

Integrated meta-QTL and in silico transcriptome assessment pinpoint major genomic regions responsible for spike length in wheat (Triticum aestivum L.).

Spike length (SL) is one of the major contributors to wheat yield. Uncovering major genetic regions affecting SL is an integral part of elucidating the genetic basis of wheat yield traits and goes further pivotal for marker-assisted selection breeding. A genome-wide meta-quantitative trait locus (MQTL) analysis of wheat SL resulted in the refinement of 48 MQTLs using 227 initial QTLs retrieved from previous studies published over the past decades. The average confidence interval (CI) of these MQTLs amounted to a 5.16-fold reduction compared to the mean CI of the initial QTLs. As many as 2240 putative candidate genes (CGs) were identified from the MQTL intervals using transcriptomics data in silico of wheat, of which 58 CGs were identified based on wheat-rice homology analysis. For the key CG affecting SL, a functional kompetitive allele-specific PCR (KASP) marker, TaPP2C-3B-KASP, was developed to distinguish TaPP2C-3B-Hap I and TaPP2C-3B-Hap II based on the single nucleotide polymorphism at the 272 bp (A/G). The frequency of the elite allelic variation TaPP2C-3B-Hap II with high SL remained relatively stable at about 49.62% from the 1960s to 1990s. Integration of MQTL analysis and in silico transcriptome data led to a significant increase in the reliability of CGs for the genetic regulation of wheat SL, and the haplotype analysis for key CGs TaPP2C-3B of SL provided insights into the biological function of the TaPP2C-3B gene.

Effect of integrated vermicompost and chemical nitrogen fertilizer for productivity of bread wheat (Triticum aestivum L.)

The study was conducted at Horo district on six (6) farmers’ fields to investigate the effect of integrated vermicompost and chemical nitrogen fertilizer for bread wheat and the soil nutrient content. The treatments consist of without any fertilizer, recommended chemical NP fertilizer, 100% N equivalent vermicompost + recommended P2O5, 75% N equivalent Vermicompost + 25% recommended N + recommended P2O5, 50% equivalent Vermicompost + 50% recommended N + recommended P2O5 and 25% equivalent Vermicompost + 75% recommended N + recommended P2O5. The experimental design was a randomized complete block design (RCBD) with three replications. Dendea seed variety with a rate of 150 Kg ha-1 was used for the trial. ANOVA analysis for after harvesting soil parameters showed significant (P<0.05) differences among treatments for available phosphorus, organic carbon, exchangeable acidity and cations exchange capacity while pH and exchangeable Ca and Mg were not statistically significant among the treatments. ANOVA showed that the treatments significantly influenced all collected yield and yield related parameters of the crop. Relatively the highest crop yield and yield related traits were obtained from T2 (recommended chemical fertilizer) while the lowest was from control (without fertilizer). The highest net income (91971.70 birr/ha) was obtained from 25% equivalence vermicompost + 75% recommended N + recommended P2O5. To have more confidence in the technology; it should be verified in the same area with the same management procedure.

Near‐infrared spectroscopy and deep neural networks for early common root rot detection in wheat from multi‐season trials

AbstractIn Australia, the soil‐borne disease common root rot (Bipolaris sorokiniana) (CRR) in wheat (Triticum aestivum L.) leads to substantial yield losses, yet has limited visible aboveground symptoms, making detection and identification labor intensive. Near‐infrared (NIR) spectroscopy offers an early potential identification solution for CRR in wheat and has previously been reported with success for crop disease detection. This study investigated the ability of nondestructive NIR spectroscopy in combination with deep neural networks (DNN), logistic regression (LR), and principal component analysis combined with support vector machines (PCA‐SVM) for early‐stage CRR detection in wheat. NIR spectra of five different wheat varieties with varying resistance to CRR were collected in two seasons of glasshouse and three seasons of field trials using a portable spectrometer. Results demonstrated that DNN outperformed LR and PCA‐SVM, achieving 66%–91% average classification accuracy in glasshouse trials and an average accuracy of 73% with up to 87% in field trials, effectively distinguishing inoculated and non‐inoculated wheat plants from seedling to anthesis stages. Validation with a third season of field data achieved an average of 77% accuracy for the most susceptible variety during the stem elongation stage. NIR reflectance within 1600–1700 nm was identified as most important for estimating CRR presence, with initial detection occurring 35 days after sowing (DAS) in the glasshouse and 46 DAS in the field. In conclusion, a NIR spectrometer with a DNN model successfully performed disease classification, with the potential as a portable early disease detection tool to assist farm management decisions.

Performance of bread wheat advanced lines under late sowing and reduced irrigation

Twenty eight advanced wheat lines and cultivar Borlaug 100 were sown on January 15 and 30, 2020, at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, México. Plots consisted of 1 bed 2 m long with two rows and 0.80 m apart with two replications, a seed density of 100 kg ha-1 with two complementary irrigations. Average daily temperature (°C), maximum, minimum, relative humidity, rainfall, heat and cold units were recorded from January 1 to May 15, 2020. The average days for heading of the group was 67 for the first sowing date and 64 for the second, while days for physiological maturity were 103 and 95, respectively. The average plant height of the group for the first and second sowing dates was 83 cm; line SOKOLL/3/PASTOR//HXL7573/2*BAU/4/PARUS/ PASTOR/5/PIHA// WORRAKATTA/2*PASTOR/3/PRL/2*PASTOR consistently reached the maximum height with 92.5 and 95 cm in the first and second dates, respectively. The average a thousand grain weight of the group was 53.8 g for the first sowing date and 43.8 for the second; sister line SOKOLL/3/PASTOR//HXL7573/2*BAU/4/ SOKOLL/WBLL1/5/PIHA// WORRAKATTA/2*PASTOR/3/PRL/2*PASTOR (PTSS14Y00057S-0B-099Y-099B-43Y-020Y) showed the highest average weight with 57.07 g. The average grain yield per plot was 340 g; sister line WBLL4//OAX93.24.35/WBLL1 /5/CROC_1/AE.SQUARROSA(205)//BORL95/3/PRL/SARA//TSI/VEE#5/4/FRET2/6/D67.2/PARANA66.270//AE.SQUARROSA(320)/3/CUNNINGHAM/4/VORB (PTSS15Y00024S-099B-099Y-099M-10Y-020Y) showed the highest yield with 420 g which was above 5 t ha-1. The average temperature was 19.09 °C with a maximum of 36.3 °C and a minimum of 1.04 °C, and the number of heat and cold units was 229 and 227, respectively.

Identification of physiological race of wheat stem rust (Puccinia graminis f.sp.tritici) and reaction of bread wheat cultivars to emerging dominant races

Identification of physiological race of wheat stem rust (Puccinia graminis f.sp.tritici) and reaction of bread wheat cultivars to emerging dominant races

Transcriptome-wide m6A methylation profile reveals its potential role underlying drought response in wheat (Triticum aestivum L.).

This study revealed the transcriptome-wide m6A methylation profile under drought stress and found that TaETC9 might regulate drought tolerance through mediating RNA methylation in wheat. Drought is one of the most destructive environmental constraints limiting crop growth and development. N6-methyladenosine (m6A) is a prevalent and important post-transcriptional modification in various eukaryotic RNA molecules, playing the crucial role in regulating drought response in plants. However, the significance of m6A in wheat (Triticum aestivum L.), particularly its involvment in drought response, remains underexplored. In this study, we investigated the transcriptome-wide m6A profile under drought stress using parallel m6A immunoprecipitation sequencing (MeRIP-seq). Totally, 4221 m6A peaks in 3733 m6A-modified genes were obtained, of which 373 methylated peaks exhibited differential expression between the control (CK) and drought-stressed treatments. These m6A loci were significantly enriched in proximity to stop codons and within the 3'-untranslated region. Integration of MeRIP-seq and RNA-seq revealed a positive correlation between m6A methylation and mRNA abundance and the genes displaying both differential methylation and expression were obtained. Finally, qRT-PCR analyses were further performed and the results found that the m6A-binding protein (TaETC9) showed significant up-regulation, while the m6A demethylase (TaALKBH10B) was significantly down-regulated under drought stress, contributing to increased m6A levels. Furthermore, the loss-of-function mutant of TaECT9 displayed significantly higher drought sensitivity compared to the wild type, highlighting its role in regulating drought tolerance. This study reported the first wheat m6A profile associated with drought stress, laying the groundwork for unraveling the potential role of RNA methylation in drought responses and enhancing stress tolerance in wheat through epigenetic approaches.