The excessive application of fertilizers in the Hetao Irrigation Area of Inner Mongolia has led to soil degradation and posed challenges to sustainable agricultural development. To identify a suitable fertilization model that achieves the dual goals of reduced fertilizer application and high yield and efficiency for spring wheat in this region, a two-factor split-plot experimental design was employed to systematically explore the effects of arbuscular mycorrhizal fungi (AMF) and nitrogen fertilizer interactions on nitrogen uptake, utilization, and yield of spring wheat. The results showed that the application of AMF significantly increased spring wheat yield (P<0.05) by 4.87%, mainly due to increases in the number of spikes and thousand-grain weight. The application of AMF optimized nitrogen distribution patterns and utilization efficiency, as evidenced by a significant increase in nitrogen translocation before anthesis (from 73.83 kg·hm^-2 to 78.09 kg·hm^-2) and post-anthesis nitrogen contribution rate (from 29.83% to 38.80%). In addition, the application of AMF significantly improved the diversity of the AMF community in the rhizosphere soil, with community diversity promoted by low nitrogen application, but inhibited by high nitrogen application. Under AMF application, the optimal nitrogen application range for spring wheat was 114.17-217.93 kg·hm^-2, which is 30%-50% lower than that of the traditional fertilization rate. Based on the above results, the yield and nitrogen use efficiency of spring wheat in Hetao irrigation area can be increased simultaneously by reasonable application of arbuscular mycorrhizal fungi and nitrogen fertilizer.

To clarify the effects of different mulching measures on the soil microecology and spring wheat yield in dryland terraces of Longzhong, a field experiment was conducted at the Dingxi Experimental Station of the Gansu Academy of Agricultural Sciences. A single-factor randomized block design was adopted with three mulching treatments: plastic film mulching (PM), straw residue mulching and incorporation (SR), and strip mulching with intact straw (SM), with no mulching (CK) as the control. The changes of these mulching measures on soil physicochemical properties, enzyme activities, ecosystem multifunctionality (EMF), and spring wheat yield were investigated. The results showed that, compared with CK, SR treatment significantly increased soil organic carbon, total nitrogen, total phosphorus, available nitrogen, and available phosphorus contents by 18.4%, 16.9%, 14.6%, 16.6%, and 12.7%, respectively. SM treatment significantly increased soil organic carbon, available nitrogen, and available phosphorus by 13.3%, 28.4%, and 9.6%, respectively. All three mulching treatments significantly improved soil water content, with the highest increase observed under PM (93.3%). SR treatment had the most pronounced effect on soil enzyme activities, followed by PM and SM. The ranking of soil EMF was SR>PM>SM>CK. PM and SR treatments significantly increased spring wheat yield by 13.4% and 18.2%, respectively. Overall, straw residue mulching and incorporation proved to be the most suitable mulching practice for the region.

To explore the feasibility of using remote sensing technology and deep learning methods to achieve early and accurate prediction of winter wheat yield on a large scale, the northern Henan region of China was taken as the research area. Using the normalized difference vegetation index, temperature, sunshine hours, precipitation and county-level yield during the period from re-greening to maturity of winter wheat from 2013 to 2022 as characteristic parameters. The Long Short-term memory (LSTM)-Convolutional Neural Networks (CNN) was used to estimate the winter wheat yield in the northern Henan region. By training the CNN-LSTM yield estimation models at different growth stages one by one, their early yield estimation ability was compared. The results showed that the CNN-LSTM yield estimation model in re-greening-maturity stages had relatively strong robustness. The average coefficient of determination (R²) in the five-fold cross-validation was 0.86, and the average root mean square error (RMSE) was 402.76 kg·hm^-2. There was a significant improvement in the yield estimation accuracy compared with the corresponding LSTM model, with the average R² increased by 0.18, and the average RMSE decreased by 188.05 kg·hm^-2. The CNN-LSTM yield estimation model in re-greening-maturity stages was a model with high stability and strong generalization ability. The R², RMSE, and mean absolute percentage error (MAPE) for yield estimation of the 2022 test set were 0.91, 337.25 kg·hm^-2, and 4.25%, respectively. Among the 32 counties (districts) in northern Henan, 75% of them had a relative error less than 5% in yield prediction, of which 21.875% had a relative error of 5% to 10% in yield prediction, and only one county (district) in Linzhou City had a relative error of 15% to 20% in yield prediction. The CNN-LSTM yield estimation model had early yield estimation ability. The R² and RMSE of the CNN-LSTM yield estimation model during the heading-anthesis stage were 0.83 and 431.98 kg·hm^-2, respectively. This model had the ability to predict winter wheat yield one month in advance. Therefore, the CNN-LSTM could be used to establish a stable and accurate winter wheat yield estimation model, thus providing strong support for agricultural decision-making.

In order to clarify the pathogen composition and pathogenicity of wheat crown rot in different ecological regions of Gansu province, more than 40 samples with typical symptoms of wheat crown rot were collected from 22 sampling sites in 11 counties and districts, including Longnan Huicheng Basin, Longdong Dry Plateau and Hexi Irrigation District in Gansu Province from grain filling to milk ripening stage. The pathogens were isolated and purified by tissue separation method. The pathogens were identified by morphological and molecular biology, and the pathogenicity of representative strains were determined by inoculation. The results showed that 76 isolates of Fusarium were screened from 104 cultures by Fusarium specific primers, and identified by morphology and TEF sequences analysis. There were 48 isolates of Fusarium pseudograminearum (63.2%), 10 isolates of F. graminearum (13.2%), 8 isolates of F. sinensis (10.5%), 6 isolates of F. equiseti (7.9%), and 4 isolates of F. acuminatum (5.2%). The pathogenicity of these isolates were significantly different, among which, that of F. pseudograminarum was the strongest, with an average disease index of 84.37; F. graminearum was the second with an average disease index of 67.06; the mean disease index of F. equiseti and F. sinensis were 66.83 and 33.97, respectively. The pathogenicity of F. acuminatum was the weakest, with an average disease index of 17.83. Combined with the isolation frequency and pathogenicity, five pathogens were identified to cause wheat crown rot in Gansu province, among which the dominant pathogen is F. pseudograminearum.

Auxin 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.