Latest ArticlesWheat stamen pistillody refers to the phenomenon of homologous transformation of wheat stamens into pistils or pistil-like structures. The stamens can be normally seeded after complete pistillody, which increases the number of grains per spike and yield of wheat. Incomplete pistillody of stamens leads to male sterility. In this paper, the flower development process of wheat, wheat floral organ development model and homeotic mutantion, as well as the four kinds of wheat stamen pistillody materials obtained at present were briefly introduced, the regulatory mechanism leading to stamen pistillody of wheat and the effect of ethylene on stamen pistillody of wheat were analyzed, which provides a reference for the study of wheat flower development, and also provides a theoretical basis for genetic improvement and molecular design breeding of wheat.
In order to determine the effects of different nitrogen (N) application amount and plant density on canopy light interception characteristics and grain yield of strong gluten wheat, Zhongmai 578, a strong gluten wheat cultivar, was used as material. Four nitrogen application levels (0, 180, 240, and 300 kg·hm-2, represented by N0, N1, N2, and N3, respectively) and three planting densities (3.0×106, 4.5×106 and 6.0×106 plants·hm-2, represented by D1, D2, and D3, respectively) were set up in the field. The differences of photosynthetic active radiation (PAR) interception rate and penetration rate, dry matter accumulation and transport, grain yield and quality of strong gluten wheat under different treatments were analyzed. The results showed that the yield and its components of wheat were affected more by N application amount than plant density. There weret more spike number, grain number per spike and grain yield under N2 and N3 conditions, among which the yield of N2D2 treatment was the highest, reaching 9 957.73 kg·hm-2. Except for N3 treatment, canopy PAR interception rate increased gradually and penetration rate decreased significantly with the increase of N application amount or plant density. N application amount, plant density and their interaction significantly affected dry matter accumulation and transport of the strong gluten wheat. Under the same N application conditions, moderately increasing plant density increased dry matter accumulation amount and contribution rate to grain yield after anthesis, which were the highest under N2D2 treatment. The sedimentation and gluten index increased with the increase of nitrogen fertilizer application amount, and gluten index reached the optimum under N2D2 treatment. Synthetically considering the utilization of photosynthetic active radiation, accumulation and transportation of dry matter, grain yield and quality of the strong gluten wheat canopy, N application amount of 240 kg N·hm-2 and plant density of 4.5×106 plants·hm-2 were the optimum combination for strong gluten wheat production under this experimental conditions.
In order to determine the optimum nitrogen topdressing amount and planting density for improving the starch quality and yield of weak gluten wheat, a weak gluten wheat variety Yangmai 15 was used as material, with four nitrogen topdressing levels (37.8, 43.2, 48.6, and 54.0 kg·hm-2, namely N1, N2, N3, and N4) and three density levels (1.8×106, 2.4×106, and 3.0×106 plants·hm-2, namely D1, D2, and D3). The effects of different nitrogen topdressing amounts and planting density on starch particle size distribution, gelatinization characteristics, protein components, grain enzyme activity and yield of wheat were characterized. The results showed that with the decreasing nitrogen topdressing, the volume and surface area percentage of B-type (≤10 μm) starch granules in wheat grains increased first and then decreased, the volume and surface area percentage of A-type (>10 μm) starch granules decreased first and then increased. After reducing the amount of topdressing nitrogen, the contents of wet gluten and protein, sedimentation value, albumin, globulin, glutenin, and gliadin content of wheat showed a downward trend, and the starch content showed an overall upward trend. The viscosity parameters such as SS activity, ADGPase activity, grain yield, starch peak viscosity and final viscosity of wheat increased first and then decreased, and the viscosity parameters such as SS activity, ADGPase activity, grain yield, and peak viscosity at N3 level were the highest. With the increase of planting density, the volume and surface area percentage of B-type starch granules showed an upward trend, and the volume and surface area percentage of A-type starch granules showed a downward trend. After increasing the planting density, the contents of albumin, globulin, glutenin, and gliadin initially decreased and then increased, and the highest content of each protein component was at D3 level. The viscosity parameters such as peak viscosity, trough viscosity, and final viscosity of wheat starch increased with the increase of density. Increasing planting density reduced wet gluten content, protein content, and sedimentation value, but increased grain starch content, SS activity, and ADGPase activity, thereby promoting grain yield. Under the conditions of this experiment, proper nitrgen supplementation and densification could improve grain yield and processing quality of wheat gluten wheat by increasing the proportion of B-type starch gains, starch viscosity parametes, SS activity and ADGPase activity.
In order to explore the correlation between the available contents of Zn (zinc), Fe (iron), Ca (calcium) and B (boron) in oat grains and their available contents in soil, 332 sites of 240 villages were selected in three districts and counties with large oat planting area in Shanxi Province (Pinglu District and Youyu County of Shuozhou City, and Zuoyun County of Datong City). The topsoil was collected and the oat grain samples were harvested. The available contents of the four elements in the soil and their contents in oat grains were determined, and the correlation between the two was analyzed. The results showed that: the available contents of the four elements in the soil of the three production areas ranked as Ca>Fe>Zn>B, where the content of Ca was high, and the contents of Fe, Zn, and B were medium or low. Comparing the available contents of the four elements in the soil of different sampling points under the same district and county, the variation of available Zn content was large, the variation of available Ca content was small, and the differences of the available Fe or B contents falled into the middle. The average accumulation of the four elements in oat grain ranked as Ca>Fe>B>Zn. Compared with the results of other studies, the average content of Fe and Zn was relatively low, while the average contents of Ca was relatively high. Compared the accumulation of the four elements in oat grains in the different sampling sites under the same district and county, the variation of B accumulation was large, the variation of Zn accumulation was small. and the variations of Ca or Fe accumulation were in the middle.Correlation analysis showed that there was significantly positive correlation between the contents of available Zn, Fe and B in soil, and there were regional differences in the correlation between the contents of these three elements and Ca content. The contents of Zn, Fe and B in oat grains were positively correlated with the accumulation of Ca. The correlation between the original accumulation of the four elements in oat grains and their available contents in soil was different in the three counties. Among them, in Youyu County, where the available content of soil, especially Ca content, was relatively high, there was significantly positive correlation between grain Zn and soil available Zn, Ca and B. The correlation between grain Zn and soil available Zn, Ca and B was significantly positive. In summary, the contents of available Fe, Zn and B in soil and the content of Fe, Zn and B in oat grains in the oat production area of this experiment could be improved. Appropriate reduction of soil available Ca content in calcareous soil area is helpful to promote Ca accumulation in oat grains.
Research on Fusarium head blight holds significant importance for agricultural production and global food security. To gain a comprehensive understanding of the research progress and emerging trends in this field, this study used CiteSpace software to systematically analyzed 1 236 literatures on Fusarium head blight in the Web of Science core collection in the past 20 years. The results indicate that the overall publication output in Fusarium head blight research had shown an upward trend, with the United States leading the field with 345 publications. International collaboration networks were relatively tight, such as those between China and the United States, China and the United Kingdom, and China and Canada. The research content primarily revolved around pathogen characteristics, disease control techniques, and the breeding of resistant varieties. Current research hotspots centered on disease resistance identification, molecular marker-assisted selection, and the development of innovative biological control agents. The prevalent technical methods primarily encompassed metabolomics, genomics, and remote sensing monitoring technologies. Looking ahead, Fusarium head blight research will place greater emphasis on interdisciplinary collaboration, aiming to develop efficient and environmentally friendly disease control strategies to address the challenges posed by global food security.
To improve the prediction accuracy of Fusarium head blight (FHB), Fusarium spores were collected and identified in the experimental fields in Yixing, Jurong, Jiangyan, Yandu, Suyu, and Tongshan in Jiangsu Province during the heading and flowering period of wheat. Disease index (DI) was investigated and Fusarium mycotoxins in harvested seeds were tested in various fields. The effect of composition of Fusarium spores on FHB and associated mycotoxins in wheat was assessed. The results showed that among the 650 Fusarium spores collected from the six regions in 2020, the ratio of Fusarium graminearum species complex (FGSC) to all the collected spores was 35.5%. In addition, the ratio of FGSC to all the collected spores in the south of the Huai River was more than 35%, followed by that in the north of Huai River (less than 27%). Moreover, DI and the content of Fusairum mycotoxins in the harvested seeds in the south of Huai River were significantly higher than that in the north of Huai River (P<0.05). Among these fields, DI and the content of Fusarium mycotoxins were significantly positively correlated with the number of FGSC (P<0.01), yet they had no correlation with the number of total spores. The composition of FGSC spores are suggested to be confirmed when the spore dispersal model was used to predict the prevalent of FHB of wheat.
In order to study the species composition and differences in pathogenicity of Fusarium crown rot of wheat pathogens in Shaanxi and Shanxi Provinces, 663 strains displaying crown rot symptoms were systematically collected from 35 sampling sites in Shaanxi and Shanxi provinces in the spring of 2023. Subsequently, five strains were randomly selected from each sampling site for pathogen isolation, and morphological observation and the molecular identification of ITS and trichothecene biosynthetic 1(Tri1) sequences were carried out. 138 strains were isolated from 175 cultures, and 85 strains of Fusarium spp. were identified by morphological and sequence analysis: including 72 strains of Fusarium pseudograminearum (84.71%), 7 strains of F. tricinctum (8.24%), 3 strains of F. graminearum (3.53%), 2 strains of F. avenaceum (2.35%), and 1 strain of F. verticillioidis (1.18%). The results showed that F. pseudograminearum was identified as the dominant pathogen causing Fusarium crown rot of wheat in Shaanxi and Shanxi Provinces. Furthermore, 32 strains of F. pseudograminearum were randomly selected to identify the pathogenicity of wheat seedlings. It was found that there were significant differences in pathogenicity among different strains. In addition, the Tri1 gene specific marker was developed in this study. Although the polymorphism of Tri1 did not directly correspond to the difference in pathogenicity, the marker effectively distinguished between F. pseudograminearum and F. graminearum. In summary, this study confirmed that the dominant strain of Fusarium crown rot of wheat in Shaanxi and Shanxi Provinces were F. pseudograminearum, and the isolates of F. pseudograminearum from different samples had significant differences in pathogenicity at seedling stage of wheat.
Fusarium head blight and Fusarium crown rot caused by Fusarium graminearum occurs severely in China, posing a threat to national food security. The NuA4 histone acetyltransferase complex regulates various developmental processes in fungi, but the functions of multiple subunits within the NuA4 complex in plant pathogenic fungi are currently unclear. To elucidate the function of Eaf7 subunit in plant pathogenic fungi, this study used F. graminearum as a model organism. Through knocking out the FgEAF7 gene, it was found that the growth rate of the Fgeaf7 mutant was significantly lower than that of the wild-type strain. However, the deletion of FgEAF7 gene did not affect conidiation, pathogenicity to wheat, and DON biosynthesis. Additionally, we found that the Fgeaf7 mutant showed decreased sensitivity to Congo red and SDS, indicating that the deletion of FgEAF7 gene affects cell wall development. Analysis of the FgEaf7 domain revealed a conserved Eaf7 domain within FgEaf7. Upon deletion of the Eaf7 domain, the FgEAF7△Eaf7 mutant exhibited similar defects to the Fgeaf7 mutant, suggesting that the Eaf7 domain is essential for the full function of FgEaf7. Transcriptomic analysis showed that over 1 800 genes were differentially expressed in the Fgeaf7 mutant, compared to the wild type, with several genes important for growth and development being downregulated. These findings indicate that FgEaf7 regulates various processes, such as vegetative growth and cell wall development in F.graminearum.
In order to clarify the current resistance status of Lolium multiflorum to the herbicides of acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS), a total of 50 populations were collected in the severe area of L. multiflorum in Zhumadian City, Henan Province and the resistance levels to pinoxaden, clodinafop-propargyl and pyroxsulam were determined by the whole-plant bioassay method. In addition, isoproturon, diflufenican, flufenacet, pyroxasulfone, diflufenican+isoproturon, and pyroxsulam were selected for bioactivity determination, and field efficacy evaluation were conducted with pyroxasulfone, flufenacet, and pyroxsulam mixed with diflufenican+isoproturon. The results showed that eight populations of L. multiflorum had high resistance to pinoxaden. The GR50 (herbicide dose causing growth reduction of fresh weight by 50%) values ranged from 146.67 g (a.i.)·hm-2 456.15 g (a.i.)·hm-2, and the resistance index (RI) ranged from 10.68 to 33.20, accounting for 16% of the tested populations. Thirty-one populations showed high level resistance to clodinafop-propargyl, with GR50 ranging from 101.82 g (a.i.)·hm-2 446.40 g (a.i.)·hm-2, and RI ranging from 10.36 to 45.41; sixteen populations had high level resistance to pyroxsulam, accounting for 32% of the total. In the bioactivity assays, except for diflufenican and pyroxsulam, the other herbicides (isoproturon, flufenacet, pyroxasulfone, diflufenican+isoproturon) showed high activity against the SC-3 population (the highest level of resistance population), with GR90 values of 1 089.36, 144.43, 51.42 and 568.69 g (a.i.)·hm-2, respectively. Field efficacy results indicated that the mixture of pyroxasulfone and diflufenican+isoproturon provided good control of L. multiflorum at the supplied dose, with fresh weight control efficacy ranging from 94.27% to 100%, and safe to wheat. Therefore, the mixture of pyroxasulfone and diflufenican+isoproturon can be used to control the serious occurrence of L. multiflorum in wheat fields.
To develop functional markers related to wheat plant type, we identified members of the wheat OTUBs family in this study, cloned a potential plant type-related gene, TaOTUB1, and analysed the expression pattern of the gene. The result showed that TaOTUB1 gene was widely expressed in various tissues of wheat and had the highest expression abundance among the 33 members of the wheat OTUBs family. The natural variation of the TaOTUB1 gene was analyzed using 748 wheat genome natural variation data, and it was found that two haplotypes, HapⅠ and HapⅡ, mainly existed in the TaOTUB1-A promoter region. The development of a dCAPS molecular marker based on SNPs at the -761 bp locus enabled the effective identification of HapⅠ and HapⅡ in 313 wheat varieties. Linkage analysis revealed that HapⅠ is an excellent haplotype for plant type improvement and yield increase. Evolutionary analysis revealed that HapⅠ is the dominant haplotype in domestic and foreign-cultivated wheat. These results can be helpful for plant type improvement and molecular marker-assisted selection breeding in wheat.