ArchiveAuxin response factor (ARF) is one of the key transcription factors that regulate plant growth and development. By binding to auxin response elements and participating in auxin related signaling pathways, ARF plays an important role in plant organ formation, signal transduction and stress response. To identify and mine ARF genes in response to salt stress in wild emmer wheat, we used a combination of Blast and HMM-search to identify ARF family genes at the genome-wide level in wild emmer wheat. The results showed twenty-two ARF genes were identified in wild emmer wheat, which are distributed on 2A, 2B, 3A, 3B, 5A, 5B, 6A, 6B, 7A, and 7B chromosomes. The 22 ARF family members were divided into three subgroups by phylogenetic tree. The prediction of promoter cis-elements showed that the promoter of ARF gene in wild emmer wheat mainly contain four types of cis-acting elements related to growth and development, hormone response, light response, and stress response. The analysis of genetic variation showed that the ARF family had a significant genetic bottleneck benefit with decreased genetic diversity during the domestication of emmer wheat. Seventeen TdARF were detected in the transcriptome data in response to salt stress. qPCR analysis showed that TdARF was mainly down-regulated under salt stress. It is suggested that TdARF may be used as candidate genes for wheat salt tolerance breeding.
The late spring cold disaster caused by low temperature in spring occurs frequently in China. It is of great significance to analyze the gene regulation mechanism of wheat in response to low temperature to resist the genetic improvement. In this study, the gene expression characteristics of wheat young spikes subjected to low temperature during meiosis was analyzed using transcriptome technology under artificially controlled environmental conditions. The results indicate that low temperature during meiosis stage can cause damage to the ultrastructure of anther tissue, leading to a significant decrease in seed setting rate. The differentially expressed genes (DEGs) in young spikes under low temperature mainly involve pathways such as hormone signal transduction, photosynthesis, circadian rhythm-plants, sugar metabolism, DNA replication, etc. The encoding genes of actin depolymerization factor (ADF), late embryonic development abundant protein (LEA), CCCH zinc finger protein, etc. were significantly upregulated at all time points of low temperature treatment, which may be involved in regulating the resistance response of wheat spikes to low temperature.
Cytokinin response regulators (RR), as important components of the cytokinin signaling pathway, perform critical functions in cytokinin signaling output and regulation of downstream gene signaling responses. In order to investigate the role of wheat RR genes in response to low-temperature stress, we cloned the A-type cytokinin responsive regulator gene TaRRA6-D from the wheat cultivar Dongnongdongmai 1 (Dn1), performed bioinformatics analysis, subcellular localization analysis, and promoter activity analysis under low-temperature. We also genetically transformed Arabidopsis wild type to create overexpression lines for phenotypic observation of root length and cold resistance evaluation. Bioinformatics analysis showed that the TaRRA6-D gene (TraesCS5D02G140200) was 1 088 bp in total length, with a coding sequence of 696 bp, which was localized to wheat chromosome 5D, and the encoded protein was an unstable hydrophobic protein. The phylogenetic tree analysis showed that the wheat TaRRA6-D protein was most closely related to the RR proteins of Aegilops tauschii and Hordeum vulgare. Transient expression analysis of transformed tobacco showed that TaRRA6-D protein was localized in the nucleus. Analysis of cis-acting elements in the promoter region of the gene showed that the TaRRA6-D promoter region contained cis-acting elements responsive to low-temperature, drought, light, and a variety of hormones. Expression pattern analysis of the transformed Arabidopsis thaliana lines showed that TaRRA6-D promoter activity was induced to express by low-temperature. Phenotypic observations showed that root length of the overexpression lines increased significantly compared with the wild type, with or without the addition of 6-BA. Seedling freezing resistance assay showed that seedlings of overexpression lines were significantly resistant to low-temperature compared with wild type, and 6-BA treatment significantly improved the freezing resistance of seedlings.
The vernalization gene VRN-D1 locus includes three major allelic variations, namely the dominant allelic variations Vrn-D1a and Vrn-D1b related to spring growth habit and semi-winter growth habit, and the recessive allelic variation vrn-D1 related to winter growth habit. In order to clarify the effects of different allelic variations at the VRN-D1 locus on the heading date and cold resistance of wheat in the Huang-Huai winter wheat region, in this study, 156 wheat varieties (lines) were used to identify the phenotypic traits of heading date and cold resistance. The wheat materials carry the same allelic variations at the known major vernalization gene VRN-A1, VRN-B1, and VRN-B3 loci as well as the photoperiod gene Ppd-D1 locus, but have different allelic variations only at the VRN-D1 locus. The results showed that there were extensive variations at the heading date, over-wintering seedling mortality rate, and dead stem rate among the 156 wheat varieties (lines). Analysis of variance indicated that the heading date was mainly affected by genotype, environment, and the interaction between genotype and environment, while the over-wintering seedling mortality rate and dead stem rate were mainly affected by genotype and environment. There were significant differences in the heading date among the three allelic variations at the VRN-D1 locus, and the heading date from early to late ranked as Vrn-D1a, Vrn-D1b, and vrn-D1. Under all environmental conditions, the cold resistance of the recessive vrn-D1 was significantly better than that of the dominant Vrn-D1a and Vrn-D1b, with the average over-wintering seedling mortality rate decreased by 19.20% and 11.18%, respectively, and the average over-wintering dead stem rate decreased by 16.53% and 8.03%, respectively. Compared with Vrn-D1a, Vrn-D1b exhibited better cold resistance, with the average over-wintering seedling mortality rate and dead stem rate decreased by 8.02% and 8.52%, respectively. The results in this study provide important information for the utilization of different allelic variations at the VRN-D1 locus to improve the heading date and cold resistance.
To accurately evaluate the resistance of wheat varieties in Huanghuai wheat area to the current circulating wheat stripe rust races, and to understand the disease resistance genes in the high-generation lines and their distribution in the wheat area, a total of 194 high-generation wheat lines from Hebei, Henan, Shandong and Anhui Provinces were collected from 2022 to 2023. CYR34 was used to identify the resistance of stripe rust fungus at seedling stage. Mixed races (CYR32, CYR33, and CYR34), artificial inoculation nurseries (Yangling, Shaanxi, YL) and natural disease nurseries (Jiangyou, Sichuan, JY) were set up to identify the resistance at the adult plant stage. Seventeen SNP markers of the 14 known disease resistance genes were used for molecular detection, and the genes that may be contained in the wheat lines were speculated. The result showed that 149 (76.40%) of the materials showed resistance to CYR34 at seedling stage. For the results of adult plant identification, 137 (70.62%) materials showed resistance in YL; 174 (86.60%) materials showed resistance in JY, and 124 materials (63.92%) showed disease resistance in both YL and JY environments. The results of molecular marker detection showed that the disease resistance genes carried in the lines were Yr6, Yr7, Yr9, YrZH84, YrSP, YrAS1676, Yr29, Yr30, Yr78, Yr86, and YrLT26, among which Yr6, Yr9, YrZH84, Yr30, and YrLT26 had a significant effect on the disease resistance of the lines, yet no materials containing Yr18 or Yr85 were detected in the lines. The combination of Yr7+Yr29+Yr9, Yr7+Yr29+YrZH84,Yr7+Yr29+YrZH84+YrSP,Yr7+Yr29+Yr9+YrZH84+YrSP and other resistance genes had good disease resistance in the field, which could be used as a reference in the breeding process. Compared with the results of stripe rust resistance in the wheat area in the past ten years, the resistance of wheat lines in the northern Huanghuai area was significantly enhanced, with 63.92% of the lines showing resistance. The level of disease resistance breeding still needs to be improved.
To provide key data for feeding oat breeding in Chengdu plain, the genetic diversity of agronomic traits of 179 oat germplasm accessions were objectivly evaluated in this research. 14 agronomic traits were evaluated, a morphological diversity index was calculated for each of them. The cluster and principal component analyses were performed for 10 selected quantitative traits among them. It was found that the trait with the highest genetic diversity index was length of flag leaf (H′=2.04), and the highest coefficient of variation (33.41%) was for vegetative tiller number. Cluster analysis divided the 179 oat germplasm accessions into five major groups. Group Ⅰ would provide excellent parent material for breeding seed varieties. Group Ⅱ was with potential for breeding high for tillering ability. Group Ⅲ was without obvious beneficial traits. The characters of group Ⅳ were general. Group Ⅴ was considered to provide excellent parent material for breeding projects involving multiple target traits. The principal component analysis reduced the 10 analyzed traits to 5 principal components which cumulatively explained 84.57% of the data variation. The first principal component was closely related to nutrient composition of forage grass. The second and the third principal component mainly reflected the leaf morphological characteristics. The fourth principal component mainly reflected tiller. The fifth principal component mainly reflected height. Tin summary, the 179 evaluated oat germplasm accessions introduced to Chengdu plain, have wide genetic diversity. Multivariate evaluation of measured traits indicated that accessions CF002393, CF003690, CF014719 and CF003691 can be used as parents to improve local oat varieties.
Fusarium head blight is a worldwide disease caused by Fusarium graminea, which seriously affects the yield and quality of wheat. The toxin of deoxynivetol (DON) produced by the grain infected by the pathogen poses a serious threat to human and animal health. In wheat, the toxicity of DON toxin is mainly caused by oxidative stress, and the main function of vitamin E in plants is antioxidant. In order to verify the effect of HGGT gene on reducing toxin accumulation in wheat grains, we developed the specific markers for HGGT gene and screened 23 varieties carrying HGGT gene from 133 national dominant varieties and some local varieties and lines. Combined with the data of two-year average diseased spikelet rate and grain DON toxin content, the correlation analysis showed that: the average diseased spikelet rate with HGGT gene was 20.47%, which was 22.67 percentage points lower than that without HGGT gene (P<0.01), indicating that HGGT gene also had a certain effect on the spread resistance of wheat scab. Under the conditions of no inoculation, the average grain DON toxin content of cultivars carrying HGGT gene was 0.12 mg·kg-1, which was 75.70% lower than that of cultivars without HGGT gene (P<0.05). Under inoculation conditions, the average grain DON toxin content of cultivars carrying HGGT gene was 5.51 mg·kg-1, which was 52.97% lower than that of cultivars without HGGT gene (P<0.01). The difference of DON toxin content in grains after inoculation and before inoculation was correlated with genotype data, and it was found that there was a significant difference in the changes of toxin content in grains between varieties carrying HGGT gene and those without HGGT gene (P<0.01), and the DON toxin accumulation with this gene was reduced by 51.93%. It was verified that HGGT gene had a significantly negative regulatory effect on the accumulation of DON toxin in wheat grains. Yangmai 18, Yangmai 33, Sumai 3, harboring HGGT, had the lower grain DON toxin content than the national standard GB2761-2011 (1 000 μg·kg-1) based on the phenotype of two years. This study could promote development of new wheat germplasm with low DON toxin.
NAC (NAM/ATAF/CUC) transcription factors are a large family of plant-specific transcription factors, consisting of highly conserved N-terminus and variable C-terminus. They are involved in a variety of biological processes and can regulate various plant traits. In this paper, the research progresses of NAC transcription factors in wheat in recent years were summarized, and their biological functions in wheat growth and environmental adaptation were systematically reviewed, mainly involving root growth, leaf senescence, grain development, and biotic and abiotic stress response. The result can enrich the regulatory network of NAC transcription factors, and provide theoretical basis for yield and quality improvement and molecular breeding in wheat.
In order to explore the feasibility of using GlutoPeak test (GPT) for rapid evaluation of wheat quality, flour samples of 150 wheat varieties (lines) were tested for the main quality indicators, including GPT indicators, sedimentation, gluten content, and dough rheological properties. The correlations between GPT indicators and other parameters were evaluated. The results showed that among the tested indicators of the wheat flour samples, water absorption had the smallest coefficient of variation (4.69%), while dough development time had the largest coefficient of variation (82.08%). The coefficients of variation for peak maximum time, startup energy, and plateau energy were all above 40%. Correlation analysis showed that there were significant correlations between the GPT indicators and dough rheological properties. The seven GPT indicators included peak maximum time (PMT), brabender units at the maximum (BEM), ante maximum (AM), post maximum (PM), startup energy (A1), plateau energy (A2) and aggregation energy (A3). The PMT showed a highly significant positive correlation with sedimentation and a highly significant negative correlation with wet gluten content, while the BEM, AM, PM and A3 exhibited a highly significant positive correlation with both sedimentation and wet gluten content. The AM, PM and A3 showed a highly significant positive correlation with water absorption and development time. The PMT had a highly significant negative correlation with water absorption, while it showed highly significant positive correlations with development time and stability time. The PMT, AM and PM were significantly positively correlated with stretch area and max resistance. Then, stepwise linear regression models were developed using the GPT indices to predict other parameters. The coefficients of determination were all significant at the 0.01 level, and the GPT indicators had high coefficients of determination (R2>0.6) for other parameters, such as stretch area, max resistance, gluten index, and stability time. A3 can predict sedimentation and wet gluten content, while PMT, AM and PM can predict stability time, stretch area, and gluten index among dough indicators.
To investigate the effects of nitrogen and phosphorus management during mid-late growth stages on starch and protein synthesis and accumulation in wheat grains, a study was conducted using the medium-strong gluten wheat cultivar Zhengmai 1860. Two single-factor completely randomized experiments were implemented across two locations (Kaifeng Longting and Zhoukou Dancheng) with consistent soil fertilization rates. Six nitrogen-phosphorus management treatments were established: CK (control): topdressing urea at jointing stage; Nt: twice topdressing urea at jointing and flowering stages; Nu: post-flowering spraying urea; P: post-flowering spraying K2HPO4; NtP: twice topdressing urea at jointing and flowering stages + post-flowering spraying K2HPO4; NuP: post-flowering spraying urea and K2HPO4. The study analyzed differences in grain soluble sugar content, starch synthase activity, starch content, amino acid content, nitrogen metabolism-related enzyme activity, protein content, dry matter accumulation at maturity, grain yield, and yield components under these treatments. The results showed that compared with CK, post-flowering urea or K2HPO4 spraying significantly increased grain soluble sugar content at both sites. Notably, the NuP treatment demonstrated a more substantial effect, registering an increase of 16.91 to 37.63 percentage points; Nt enhanced starch synthase activity only at Zhoukou Dancheng, while P significantly increased both bound and soluble starch synthase activities at both sites, with NuP exhibiting superior effects (18.34%—32.24% increase); Nt had no significant effect on starch content, but NtP significantly increased starch content at both sites. NuP improved starch content only at Kaifeng Longting; Nu increased amino acid content only at Zhoukou Dancheng, whereas NuP enhanced it significantly at both sites; NuP significantly boosted glutamine synthetase and glutamate synthase activities at both sites. Nt showed no effect on protein content, but NtP increased protein content at Zhoukou Dancheng, and the NuP treatment significantly increased the protein content in wheat grains at both experimental sites. During the maturity stage, the increase ranged from 3.35 to 3.68 percentage points; Both NtP and NuP significantly increased grain yield at both sites (8.12%—11.51%); In conclusion, combined treatments of twice topdressing urea at jointing and flowering stages with post-flowering K2HPO4 spraying (NtP) or post-flowering co-application of urea and K2HPO4 (NuP) effectively promoted starch and protein synthesis/accumulation and enhanced yield in wheat grains.
To explore the effects of amino acid chelated zinc on the yield and quality of wheat, Zhengmai 1860 was used as the experimental material. The treatments included spraying 0.2% and 0.4% concentrations of zinc sulfate, zinc aspartate, and zinc glycinate after anthesis, with spraying water as the blank control. The effects of zinc spraying on the yield and quality of wheat were studied. The results showed that spraying 0.2% zinc aspartate significantly increased the 1 000-grain weight of wheat at the two experimental sites of Longting, Kaifeng and Dancheng, Zhoukou by 6.17% and 6.58%, respectively; significantly increased the grain yield of wheat at the two sites by 5.05% and 5.32%, respectively; and significantly increased the bulk density of wheat at the two sites by 2.16% and 2.32%, respectively. Spraying zinc significantly reduced the degree of softening of wheat flour at the two sites by 16.06% to 26.98% and 12.21% to 34.27%, respectively. Spraying zinc aspartate significantly increased the wet gluten content of wheat flour at the two sites by 5.72% to 10.51% and 5.28% to 6.53%, respectively; significantly increased the maximum resistance of dough at the two sites by 17.27% to 20.96% and 12.25% to 14.13%, respectively; and significantly increased the sedimentation index of wheat flour at Longting, Kaifeng site by 19.69% to 28.14%. Spraying 0.2% zinc glycinate significantly increased the wet gluten content of wheat flour at the two sites by 6.27% and 7.40%, respectively; significantly increased the resistance at constant deformation of dough at the two sites by 18.37% and 8.21%, respectively; and significantly increased the dough development time and stability time of wheat flour at the Dancheng, Zhoukou site by 36.53% and 30.78%, respectively. In conclusion, spraying 0.2% zinc aspartate after anthesis can increase the 1 000-grain weight, grain yield and test weight of wheat, reduce the degree of softening of wheat flour, and increase the wet gluten content and tensile resistance of dough.
In order to investigate the effects of different nitrogen fertilizer application rates on the starch physicochemical properties and structure of wheat grain, and to analyse the reasons for the differences in the starch physicochemical properties, a strong-gluten variety Fengdecunmai 5 and a medium-gluten variety Bainong 207 were selected as the experimental materials, and set up four nitrogen application rates of 0, 180, 240, and 300 kg·hm-2 noted as N0, N180, N240, N300 respectively. Starch physicochemical properties and structural characteristics under different nitrogen fertiliser application rates were determined. The results showed that with the increase of nitrogen application rate, the peak viscosity and swelling potential of the two varieties wheat were first rising and then falling, the peak temperature, enthalpy, content of branched starch B2 and B3 long chains, relative crystallinity, degree of surface ordering, number proportion of large starch granules all showed a trend of first declining and then rising. Fengdecunmai 5 and Bainong 207 all the extreme values were N240 and N180 treatment respectively. Compared with the N0 treatment, the N240 treatment of Fengdecunmai 5 and the N180 treatment of Bainong 207 showed an average increase in swelling potential of 36.74% and 7.23%, an average decrease in enthalpy of 18.94% and 27.43%, an average decrease in relative crystallinity of 16.29% and 9.82%, and an average decrease in the degree of order of the starch surface layer of 5.09% and 4.21%, respectively. In conclusion, the moderate application of nitrogen fertilizer can improve the starch physicochemical properties and structure of wheat grain.
To clarify the effects of one-time basal application of different types of controlled-release fertilizers on rice-stubble wheat, a field experiment was conducted using the wheat cultivar Huaimai 139. Four types of controlled-release fertilizer treatments were applied: vegetable oil-coated controlled-release compound fertilizer (A, N 26%), polyurethane-coated controlled-release compound fertilizer (B, N 32%), polyurethane-coated controlled-release nitrogen fertilizer (C, N 43%), and water-based resin-coated nitrogen fertilizer (D, N 43%). A treatment with split application of urea was used as control (CK, nitrogen applied at a basal to tillering to jointing to booting ratio of 5∶1∶2∶2), and a non-nitrogen treatment (N0) was set up caculate the nitrogen efficiency. The dry matter production, nitrogen accumulation, yield and economic benefits of rice-stubble wheat under different treatments were analyzed. The results showed that, compared with CK, A and B treatments significantly reduced nitrogen accumulation from jointing to heading and from heading to maturity, as well as nitrogen use efficiency. In A and B treatments, the number of spikes, grains per spike, and thousand-kernel weight were significantly decreased, leading to lower yield. C treatment significantly increased nitrogen accumulation at all key growth stages, enhanced photosynthetic capacity, nitrogen use efficiency, dry matter accumulation at maturity, thousand-kernel weight, yield, and net economic benefits. Yields in 2021-2022 and 2022-2023 increased by 3.89% and 5.35%, respectively, and the net benefit in 2022-2023 increased by 3.27%. D treatment showed no significant difference compared with CK in nitrogen accumulation patterns or yield, indicating stable performance. In conclusion, one-time basal application of polyurethane-coated nitrogen fertilizer can effectively meet nitrogen demand during mid-to-late growth stages, optimize yield formation, and improve both yield and economic efficiency.
To understand the effect of high-throughput non-destructive monitoring of wheat grain filling rate (GFR) based on UAV multi-spectral, 565 wheat germplasm accessions were used as experimental materials over two growing seasons (2022 and 2023). UAVs were used to collect temporal spectral vegetation indices (SVIs) during the grain filling period, along with synchronized measurements of grain weight. The logistic function was applied to fit the dynamic changes between SVIs and grain weight, and the red-edge chlorophyll index (CIRE) was identified as the SVI most closely related to GFR. Machine learning models, including Random Forest Regressor (RFR), Support Vector Regression (SVR), and Linear Regression (LR), were constructed to predict GFR, and their performance was evaluated using r2 and RMSE. The results showed that the r2 values of the logistic fitting dynamic curves between SVIs and measured grain weight reached 0.87 and 0.92, respectively. The dynamic change rate of CIRE exhibited a significantly positive correlation with GFR (r=0.4-0.43, P<0.05). Among the models, RFR demonstrated the best predictive performance, with r2 values of 0.88 and 0.89 and RMSE values of 0.27 and 0.32 for the full datasets in 2022 and 2023, respectively, significantly outperforming SVR and LR. Similarly, RFR achieved higher prediction accuracy and generalization capability in specific genotype datasets. Therefore, based on UAV multi-spectral data, the wheat grain filling rate was monitored by combining CIRE and RFR with high-precision and high-throughout. This method provides essential technical support for the evaluation of wheat germplasm resources and breeding for stress resistance.
Wheat above ground biomass (AGB) serves as a crucial indicator for assessing its growth status. Currently, unmanned aerial vehicles (UAVs) equipped with various optical sensors have been extensively utilized for monitoring wheat AGB. However, in the late stages of wheat growth, high vegetation coverage hinders optical sensors from capturing information within the canopy, thereby diminishing the accuracy of AGB monitoring. To mitigate this issue, this study incorporated point cloud characteristic parameters (PCs), which are related to canopy height, as representative indicators of canopy structure for estimating AGB using spectral indices, including color indices (CIs) and vegetation indices (VIs). The accuracy of AGB estimation models was then compared before and after the inclusion of PCs. The results revealed variations in the effectiveness of AGB estimation using different characteristic parameters during the jointing, heading, and filling stages of wheat growth. In the training set, the effect of CIs was slightly lower than that of VIs, while in the validation set, it was marginally higher. Although PCs did not exhibit the most remarkable performance across the three key periods, their stability was notably strong, and certain canopy structural characteristics demonstrated potential for AGB prediction. When individual features were used for AGB prediction, the r2 values ranged from 0.47 to 0.75. In contrast, integrating the three features of CIs, VIs, and PCs substantially enhanced the accuracy of the AGB estimation model. Specifically, during the three growth stages, the model's r2 values were 0.79, 0.81, and 0.77, and the root mean square error (RMSE) was 0.42, 0.74, and 0.80 t·hm-2, respectively. Among different types of remote sensing features, support vector machine regression (SVM) provided superior estimation results compared to Gaussian process regression (GPR). Therefore, by integrating the three features (CIs, VIs, and PCs) and employing the SVM algorithm, an effective estimation of wheat AGB can be achi.