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BACKGROUND: Advanced cancer patients with good Eastern Cooperative Oncology Group (ECOG) performance status (score 0-1) are underrepresented in current qualitative reports compared with their dying counterparts. AIM: To explore the experiences and care needs of advanced cancer patients with good ECOG. DESIGN: A qualitative phenomenological approach using semi-structured interview was employed. Data was analyzed using the Colaizzi's method. SETTING/PARTICIPANTS: Purposive sample of terminal solid cancer patients on palliative care aged 18-70 years with a 0-1 ECOG score were recruited from a tertiary general hospital. RESULTS: Sixteen participants were interviewed. Seven themes were generated from the transcripts, including experiencing no or mild symptoms; independence in self-care, decision-making, and financial capacity; prioritization of cancer growth suppression over symptom management; financial concerns; hope for prognosis and life; reluctance to discuss death and after-death arrangements; and use of complementary and alternative medicine (CAM) and religious coping. CONCLUSIONS: Advanced cancer patients with good ECOG have distinct experiences and care needs from their dying counterparts. They tend to experience no or mild symptoms, demonstrate a strong sense of independence, and prioritize cancer suppression over symptom management. Financial concerns were common and impact their care-related decision-making. Though being hopeful for their prognosis and life, many are reluctant to discuss death and after-death arrangements. Many Chinese patients use herbal medicine as a CAM modality but need improved awareness of and accessibility to treatment options. Healthcare professionals and policy-makers should recognize their unique experiences and needs when tailoring care strategies and policies.
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Neoplasias , Humanos , Neoplasias/terapia , Cuidados Paliativos , Prognóstico , Autocuidado , Pesquisa QualitativaRESUMO
The challenge of wheat leaf rust on wheat production is a recurring issue. Race identification of Puccinia triticina (Pt) serves as the foundation for preventing and controlling this disease. In a 15-year study, we identified 2,900 isolates of Pt from 20 provinces, cities, or autonomous regions in China during 2007 to 2021 and found 332 virulence phenotypes with 11 predominant phenotypes: PHT (8.3%), THT (5.4%), PHK (4.5%), PHJ (3.7%), THJ (3.6%), SHJ (3.5%), THS (3.3%), FGD (2.9%), THK (2.6%), PHS (2.4%), and PHD (2.0%). The virulence frequency for 40 Lr genes was identified across different years and areas; one major reason for the race dynamics was the attenuation to Lr1 and Lr26, which was more evident in southwest China. Lr9, Lr24, Lr28, Lr38, and Lr42 maintained effectiveness in China, while Lr2c, Lr10, Lr12, Lr14a, Lr14b, Lr22a, Lr33, and Lr36 nearly lost their effectiveness against wheat leaf rust disease. No significant difference was found among predominant phenotypes in different areas (P > 0.1). However, 12 Lr sites were found to have differences in virulence frequencies with values greater than 20% across various locations; furthermore, the lowest and highest virulence values were observed in north China (Area 1) and northwest China (Area 5), respectively. According to phenotype dynamics, PHT, THT, FGD, THK, and PHS are more likely to persist over time. In addition, much attention should be given toward discovering rising combinations of virulent phenotypes.
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Basidiomycota , Puccinia , Basidiomycota/genética , Virulência/genética , Doenças das Plantas/genética , ChinaRESUMO
Long-distance dispersal of plant pathogens in the air can establish diseases in other areas and lead to an increased risk of large-scale epidemics. Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat in China. Hubei is an important overwintering region for Pst in China, and this overwintering region is a determinant of stripe rust severity in eastern China. In 2017, stripe rust disease caused a pandemic in the Hubei region and resulted in great yield losses of wheat. To explain the disease pandemic, a total of 595 single-lesion samples of stripe rust were collected in spring, including 204 in five provinces in 2017 and 391 in four provinces in 2018, and genotyped with 13 simple sequence repeat makers. The samples were classified into 12 subpopulations based on the locations and year of collection. Genetic diversity was determined for the collection and each subpopulation. Differentiation and gene flow were determined between subpopulations. STRUCTURE analyses and discriminant analysis of principal components were conducted, and the results were used to infer the relationships between subpopulations. Our study revealed a new route of Pst transmission from the Yunnan-Guizhou Plateau to the Hubei region. The Pst inoculum of northwestern Hubei came from Gansu in the northwest, whereas the inoculum in southern Hubei came from the Yunnan-Guizhou Plateau via upper airflow. After the initial inocula infected wheat plants and multiplied in northern and southern Hubei, urediniospores produced in these regions further spread together along the middle reach of Hanshui Valley and made exchanges there. The finding of the new transmission route of Pst is important for improving integrated stripe rust disease management, which should have a profound impact on the balance of agricultural ecology in China.
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Basidiomycota , Doenças das Plantas , Doenças das Plantas/genética , China , Basidiomycota/genética , Triticum/genéticaRESUMO
Rust fungi in Pucciniales have caused destructive plant epidemics, have become more aggressive with new virulence, rapidly adapt to new environments, and continually threaten global agriculture. With the rapid advancement of genome sequencing technologies and data analysis tools, genomics research on many of the devastating rust fungi has generated unprecedented insights into various aspects of rust biology. In this review, we first present a summary of the main findings in the genomics of rust fungi related to variations in genome size and gene composition between and within species. Then we show how the genomics of rust fungi has promoted our understanding of the pathogen virulence and population dynamics. Even with great progress, many questions still need to be answered. Therefore, we introduce important perspectives with emphasis on the genome evolution and host adaptation of rust fungi. We believe that the comparative genomics and population genomics of rust fungi will provide a further understanding of the rapid evolution of virulence and will contribute to monitoring the population dynamics for disease management.
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Basidiomycota , Doenças das Plantas , Basidiomycota/genética , Mapeamento Cromossômico , Fungos/genética , Genômica , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Virulência/genéticaRESUMO
Wheat leaf rust (caused by Puccinia triticina Erikss.) is among the major diseases of common wheat. The lack of resistance genes to leaf rust has limited the development of wheat cultivars. Wheat-Agropyron cristatum (A. cristatum) 2P addition line II-9-3 has been shown to provide broad-spectrum immunity to leaf rust. To identify the specific A. cristatum resistance genes and related regulatory pathways in II-9-3, we conducted a comparative transcriptome analysis of inoculated and uninoculated leaves of the resistant addition line II-9-3 and the susceptible cultivar Fukuhokomugi (Fukuho). The results showed that there were 66 A. cristatum differentially expressed genes (DEGs) and 1389 wheat DEGs in II-9-3 during P. triticina infection. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and gene set enrichment analysis (GSEA) revealed that the DEGs of II-9-3 were associated with plant-pathogen interaction, MAPK signaling pathway-plant, plant hormone signal transduction, glutathione metabolism, and phenylpropanoid biosynthesis. Furthermore, many defense-related A. cristatum genes, such as two NLR genes, seven receptor kinase-encoding genes, and four transcription factor-encoding genes, were identified. Our results indicated that the key step of resistance to leaf rust involves, firstly, the gene expression of chromosome 2P upstream of the immune pathway and, secondly, the effect of chromosome 2P on the co-expression of wheat genes in II-9-3. The disease resistance regulatory pathways and related genes in the addition line II-9-3 thus could play a critical role in the effective utilization of innovative resources for leaf rust resistance in wheat breeding.
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Agropyron , Basidiomycota , Agropyron/genética , Basidiomycota/genética , Cromossomos de Plantas , Resistência à Doença/genética , Perfilação da Expressão Gênica , Melhoramento Vegetal , Doenças das Plantas/genética , Transcriptoma , Triticum/genéticaRESUMO
BACKGROUND: Dwarf bunt, which is caused by Tilletia controversa Kühn, is a soilborne and seedborne disease that occurs worldwide and can lead to 70% or even total losses of wheat crops. However, very little information is available about the histological changes that occur in dwarf bunt-resistant and dwarf bunt-susceptible wheat plants at the tillering stage (Z21). In this study, we used scanning electron microscopy and transmission electron microscopy to characterize the histological changes at this stage in resistant and susceptible wheat cultivars infected by T. controversa. RESULTS: Using scanning electron microscopy, the root, stem, and leaf structures of resistant and susceptible cultivars were examined after T. controversa infection. The root epidermal and vascular bundles were more severely damaged in the susceptible T. controversa-infected plants than in the resistant plants. The stem cell and longitudinal sections were much more extensively affected in susceptible plants than in resistant plants after pathogen infection. However, slightly deformed mesophyll cells were observed in the leaves of susceptible plants. With transmission electron microscopy, we found that the cortical bundle cells and the cell contents and nuclei in the roots were more severely affected in the susceptible plants than in the resistant plants; in the stems and leaves, the nuclei, chloroplasts, and mesophyll cells changed significantly in the susceptible plants after fungal infection. Moreover, we found that infected susceptible and resistant plants were affected much more severely at the tillering stage (Z21) than at the seedling growth stage (Z13). CONCLUSION: Histological changes in the wheat roots, stems and leaves were much more severe in T. controversa-infected susceptible plants than in infected resistant plants at the tillering stage (Z21).
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Basidiomycota/patogenicidade , Doenças das Plantas/microbiologia , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Interpretação Estatística de Dados , Resistência à Doença , Suscetibilidade a Doenças , Hifas/patogenicidade , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Células Vegetais/microbiologia , Células Vegetais/ultraestrutura , Folhas de Planta/citologia , Folhas de Planta/microbiologia , Raízes de Plantas/citologia , Raízes de Plantas/microbiologia , Caules de Planta/citologia , Caules de Planta/microbiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Triticum/citologiaRESUMO
Tilletia foetida (syn. T. laevis) leads to wheat common bunt, a worldwide disease that can lead to 80% yield loss and even total loss of production, together with degrading the quality of grains and flour by producing a rotten fish smell. To explore the potential microbial community that may contribute to the control of soil- and seed-borne pathogens, in this study, we analyzed the effects of the plant pathogenic fungus T. foetida on rhizosphere soil microorganisms in wheat seeds coated with different concentrations of a fungicide (Jianzhuang) used to control the disease. To analyze the bacterial and fungal abundance in T. foetida-infected and mock-infected plants, the microorganisms were sequenced using high-throughput HiSeq 2500 gene sequencing. The results showed that bacterial communities, including Verrucomicrobia, Patescibacteria, Armatimonadetes, Nitrospirae, Fibrobacteres, Chlamydiae, and Hydrogenedentes, and fungal communities, including Basidiomycota and Ciliophora, were more prevalent in the mock group than in the T. foetida-infected group, which may contribute to the control of wheat common bunt. Moreover, cluster and PCoA analysis revealed that replicates of the same samples were clustered together, and these results were also found in the distance index within-group analysis for bacterial and fungal communities in the T. foetida-infected and mock groups.
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Microbiota , Triticum , Basidiomycota , Doenças das Plantas , Rizosfera , Sementes , Solo , Microbiologia do SoloRESUMO
Puccinia striiformis f. sp. tritici is the causal agent of wheat yellow rust with records of regular and severe epidemics in China. This study explored the population dynamics of the yellow rust pathogen in Gangu, northwestern China. In Gangu, the Weihe River runs from west to east and divides Gangu into three regions: North and South mountain, with the valley in between. To study the genetic structure of the pathogen in local populations, samples were collected over 3 years from the three regions at different altitudes both within and between the wheat cropping seasons. A total of 811 P. striiformis f. sp. tritici isolates were successfully genotyped using 16 simple sequence repeat markers. The results suggest that P. striiformis f. sp. tritici can survive year-round in Gangu. The P. striiformis f. sp. tritici populations migrated among the regions, and the migration pattern was not related to altitude. The oversummering populations in the North and South mountain regions were genetically different from each other; and the P. striiformis f. sp. tritici populations collected from the lower altitude in the valley had no relationship with any of the populations collected in the spring or fall, indicating that they too have a different origin. Signatures of random mating were found in the populations collected in both North and South mountain regions, but not in the valley populations.
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Basidiomycota , Triticum , Basidiomycota/genética , Repetições de Microssatélites/genética , Doenças das Plantas , Puccinia , Recombinação Genética , Estações do AnoRESUMO
Wheat common bunt is a serious disease that may lead to yield losses of 75-80% in many wheat regions of the world (Mathre 1996). The disease may reduce yield and flour quality by producing trimethylamine, a compound that smells like rotting fish (Castlebury et al. 2005; Hoffmann 1981; Mathre 1996). Two closely related basidiomycete species, Tilletia caries (DC.) Tul. & C. Tul. [syn. T. tritici (Bjerk.) Wint.] and T. laevis J. G. Kühn [syn. T. foetida (Wallr.) Liro], cause wheat common bunt. Teliospore morphology is used to differentiate the two species. Teliospores of T. caries have reticulates on the surface while teliospores of T. laevis have a smooth surface (Pieczul et al. 2018). T. laevis was reported in Liaoning, Shaanxi, Shandong, Beijing, Hebei, Shanxi, Jilin, Heilongjiang, Jiangsu, Gansu, Xinjiang, Sichuan, Yunnan, Inner Mongolia, and Tibet (Guo 2011; Wang 1963), but not in Henan, the biggest wheat production province in China, before the present study. In July 2019, we found wheat common bunt in three fields grown with cultivar Zhengmai 618 in Yugong Mountain, Henan province. The diseased wheat heads had bunt balls filled with black powder with fishy smell. The disease incidences in these fields were 20-50%, but no common bunt was found in other nearby fields. About 200 diseased heads were sampled from the three fields. Teliospores from each head were observed under a microscope, and they all had smooth surface. Observations using a scanning electron microscope also showed smooth-surfaced teliospores. Teliospores were measured 13.5 to 18.5 µm in diameter. After surface sterilization of diseased heads using 0.25% NaClO for 5 min, teliospore suspension (1×106/ml) was made using sterilized distilled water and spread on water agar (200 µl per plate), and the plates were kept at 15°C with 24 h light (Goates and Hoffman 1987). On the 6th days, teliospores were germinated. Based on the disease symptoms, teliospore morphology, and germination, the bunt fungus was identified as T. laevis. To fulfill Koch's postulates, 1 ml of germinating teliospore suspension at the concentration of 106 spores/ml was injected into the heads of susceptible wheat cultivar (Dongxuan 3) at the boot stage with a syringe, and the plants injected with sterile ddH2O were used as control. The inoculated plants were grown in a growth chamber at 17°C with 50% humidity and 24 h light (300 µmol/m2/s). After one month at the ripening stage, the kernels of the inoculated plants were filled with black teliospores releasing fishy smell, and the control plants did not have bunt heads. Under a scanning electron microscope, teliospores from the inoculated heads had smooth surface and were measured 13.5 to 18.5 µm in diameter, similar to the teliospores of bunt heads from the fields. The fungus was also confirmed through molecular characterization using sequence characterized amplification region (SCAR) markers specific for T. laevis, and the expected 660 bp (Yao et al., 2019) and 286 bp (Zhang et al. 2012) bands were obtained separately from the teliospore samples from both the fields and growth chamber. The collection named as CGMCC 3.20112 was deposited in China General Microbiological Culture Collection Center. To the best of our knowledge, this is the first report of T. laevis causing wheat common bunt in Henan Province of China. Because the pathogen is seedborne and soilborne, the disease may become a high risk to wheat production in Henan and other provinces of China.
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This is the first study of proteomics of wheat bunt fungi Tilletia controversa (TCK), T. caries (TCT), and T. foetida (TFL) using the iTRAQ technique. Based on the relative quantities of specific proteins between each two pathogens, we found 50 up-regulated and 80 down-regulated protein genes in TCK compared to TFL, 62 up-regulated and 82 down-regulated protein genes in TCT compared to TFL, 47 up-regulated and 30 down-regulated protein genes in TCK compared to TCT, and there were 1 protein of up-regulated and 4 proteins of down-regulated in the three pairs. These protein data could be of great value for exploring the key proteins which play an important role in the interactions of these pathogens with their host. Some of them could be valuable for differentiating the three pathogens with monoclonal antibodies produced by the specific proteins and may enable in-site detection of the pathogens and performing routine monitoring as a diagnostic assay in wheat shipments.
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Basidiomycota/genética , Proteínas Fúngicas/análise , Regulação Fúngica da Expressão Gênica/genética , Doenças das Plantas/microbiologia , Proteômica/métodos , Triticum/microbiologia , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Primers do DNA/genética , DNA Fúngico/genética , Proteínas Fúngicas/genética , Perfilação da Expressão GênicaRESUMO
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is an important disease on wheat, seriously threatening wheat production worldwide. China is one of the largest stripe rust epidemic regions in the world. The pathogen sexual reproduction and migration routes between Tibet and the other regions in China are still unknown. In this study, we obtained 961 Pst isolates from 1,391 wheat leaf samples from Gansu (277), Shaanxi (253), Sichuan (172), and Tibet (259), comprising 13 natural populations, and genotyped them with simple sequence repeat (SSR) markers. The isolates can be divided into two distinct clusters based on DAPC and STRUCTURE analyses. The genetic diversity of Longnan (in Gansu) and Yibin (in Sichuan) populations was the highest and lowest among the 13 populations, respectively. The hypothesis of multilocus linkage disequilibrium was rejected for the populations from Linzhi in the Himalayan, Longnan, Hanzhong, Guangyuan, Mianyang, Liangshan, and Chendu in the south Qinling Mountains at the level of P = 0.01, which indicated significant linkage among markers in these populations. Populations in the other regions had extensive gene exchange (Nm > 4); little gene exchange was found between Tibet and the other regions (Nm < 1). The results suggest that the Tibet epidemic region of Pst is highly differentiated from the other epidemic regions in China.
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Fusarium head blight (FHB) is an important wheat disease worldwide; however, its effects on the physiological parameters in plants with different levels of FHB resistance remain unclear. Here, we evaluated the effects of Fusarium graminearum infection on yield and the photosynthesis-associated parameters Pn, Gs, and Ci of wheat flag leaves and determined the influence of FHB resistance. The FHB-resistant wheat genotype L699 and its susceptible sister line L661 were point- and spray-inoculated. Photosynthesis-associated parameters were subsequently measured using a modulated photosynthesis system, and FHB intensity was evaluated. Compared with L661, FHB caused more significant reductions in the net photosynthetic rate and stomatal conductance of flag leaves in L699. However, FHB caused a larger reduction in the 1000-grain weight and total grain weight per spike in L661 compared with L699. Independence sample t test showed that FHB resistance was significantly higher in L699 compared with L661. We concluded that under the conditions of the present study, FHB had a significantly greater effect on net photosynthesis in the resistant line compared with the susceptible line; however, it had a greater impact on yield components in the susceptible line. These results provide a new insight into the physiological cost of host resistance to FHB.
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BACKGROUND: Stripe rust, a highly destructive foliar disease of wheat (Triticum aestivum), causes severe losses, which may be accompanied by reduced photosynthetic activity and accelerated leaf senescence. METHODS: We used suppression subtractive hybridization (SSH) to examine the mechanisms of resistance in the resistant wheat line L693 (Reg. No. GP-972, PI 672538), which was derived from a lineage that includes a wide cross between common and Thinopyrum intermedium. Sequencing of an SSH cDNA library identified 112 expressed sequence tags. RESULTS: In silico mapping placed one of these tags [GenBank: JK972238] on chromosome 1A. Primers based on [GenBank: JK972238] amplified a polymorphic band, which co-segregated with YrL693. We cloned a candidate gene encoding wheat copper-binding protein (WCBP1) by amplifying the polymorphic region, and we mapped WCBP1 to a 0.64 cM genetic interval. Brachypodium, rice, and sorghum have genes and genomic regions syntenic to this region. DISCUSSION: Sequence analysis suggested that the resistant WCBP1 allele might have resulted from a deletion of 36-bp sequence of the wheat genomic sequence, rather than direct transfer from Th. intermedium. qRT-PCR confirmed that WCBP1 expression changes in response to pathogen infection. CONCLUSIONS: The unique chromosomal location and expression mode of WCBP1 suggested that WCBP1 is the putative candidate gene of YrL693, which was involved in leaf senescence and photosynthesis related to plant responses to stripe rust infection during the grain-filling stage.
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Proteínas de Transporte/metabolismo , Resistência à Doença , Doenças das Plantas/microbiologia , Folhas de Planta/fisiologia , Triticum/imunologia , Triticum/microbiologia , Sequência de Aminoácidos , Proteínas de Transporte/química , Proteínas de Transporte/genética , Clorofila/metabolismo , Segregação de Cromossomos , Clonagem Molecular , Etiquetas de Sequências Expressas , Fluorescência , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Ligação Genética , Genótipo , Dados de Sequência Molecular , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Filogenia , Mapeamento Físico do Cromossomo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase , Polimorfismo Genético , Pseudomonas syringae/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Plântula/microbiologia , Triticum/genéticaRESUMO
Tilletia controversa Kühn (TCK) is an important quarantine pathogen that causes wheat dwarf bunt and results in devastating damage to wheat production. The fungus is difficult to be distinguished from T. caries and T. laevis, which cause wheat common bunt, based on morphological, physiological and symptomatological characteristics of the pathogens. The traditional detection of the fungus can be a long and tedious process with poor accuracy. The inter-simple sequence repeat (ISSR) technique has been used for identifying molecular markers for detection of TCK. Of 28 ISSR primers screened, ISSR-859 amplified a specific 678 bp DNA fragment from all TCK isolates but not from any isolates of the common bunt fungi or other pathogenic fungi tested. Based on the fragment sequence, a pair of sequence characterized amplified region (SCAR) primers was designed, which amplified a 372 bp DNA fragment specifically in TCK. The SCAR marker was detected using as low as 1 ng template DNA of TCK, and was also detected using broken teliospores and DNA from asymptomatic wheat samples. We developed the SYBR Green I and TaqMan Green I and TaqMan real-time polymorphism chain reaction methods to detect TCK with the detection limit of 0.1 fg with asymptomatic wheat samples. Further work is needed to develop a rapid test kit for this pathogenic fungus using the designed specific primers.
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Basidiomycota/genética , Basidiomycota/isolamento & purificação , Marcadores Genéticos , Micologia/métodos , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Triticum/microbiologia , Benzotiazóis , Primers do DNA/genética , DNA Fúngico/genética , Diaminas , Compostos Orgânicos/metabolismo , Quinolinas , Sensibilidade e Especificidade , Coloração e Rotulagem/métodosRESUMO
Tilletia controversa J. G. Kühn is the causal agent of wheat dwarf bunt (DB), a destructive disease causing tremendous economic losses. Small cysteine-rich secreted proteins (SCPs) of plant fungi are crucial in modulating host immunity and promoting infection. Little is known about the virulence effectors of T. controversa. Here, we characterized TcSCP_9014, a novel effector of SCPs, in T. controversa which suppressed programmed cell death triggered by BAX without relying on its signal peptide (SP). The SP in the N-terminus of TcSCP_9014 was functional in the secretory process. Live-cell imaging in the epidermal cells of Nicothiana benthamiana suggested that TcSCP_9014 localized to the plasma membrane, cytoplasm, and nucleus. Furthermore, yeast cDNA library screening was performed to obtain the interacting proteins in wheat. Yeast two-hybrid and BiFC assays were applied to validate the interaction of TcSCP_9014 with TaMTAN and TaGAPDH. Our work revealed that the novel effector TcSCP_9014 is vital in modulating plant immunity, which opens up new avenues for plant-pathogen interactions in the T. controversa infection process.
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Fusarium head blight (FHB) is one of the most destructive wheat diseases worldwide. To understand the impact of human migration and changes in agricultural practices on crop pathogens, here population genomic analysis with 245 representative strains from a collection of 4,427 field isolates of Fusarium asiaticum, the causal agent of FHB in Southern China is conducted. Three populations with distinct evolution trajectories are identifies over the last 10,000 years that can be correlated with historically documented changes in agricultural practices due to human migration caused by the Southern Expeditions during the Jin Dynasty. The gradual decrease of 3ADON-producing isolates from north to south along with the population structure and spore dispersal patterns shows the long-distance (>250 km) dispersal of F. asiaticum. These insights into population dynamics and evolutionary history of FHB pathogens are corroborated by a genome-wide analysis with strains originating from Japan, South America, and the USA, confirming the adaptation of FHB pathogens to cropping systems and human migration.
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Solid pseudopapillary tumor of the pancreas is a rare pancreatic neoplasm that typically occurs in young females. As a low-grade malignancy, the tumor seldom recurs and metastasizes. Management of liver metastasis from such a tumor remains unclear. We present a case of a young girl with liver metastasis due to solid pseudopapillary tumor of the pancreas. She was admitted with chief complaints of epigastric mass on palpation for 16 months and upper abdominal pain for 2 months. An abdominal CT scan detected a mass in the pancreas and multiple nodules in the liver. Then, percutaneous CT-guided tru-cut biopsy was performed and pathological diagnosis of the biopsy material revealed solid pseudopapillary tumor of the pancreas. At 3 months after surgical resection of the pancreatic and liver tumors, CT scan found nodules in her liver. The patient received treatment with transcatheter arterial chemoembolization. She remained well during the 3 years of follow-up with no evidence of recurrence. Therefore, it is suggested that although solid pseudopapillary tumor of the pancreas may be associated with malignant potentiality, a favorable prognosis can also be obtained via rigorous treatment.
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Wheat dwarf bunt leads to the replacement of seeds with fungal galls containing millions of teliospores of the pathogen Tilletia controversa Kühn. As one of the most devastating internationally quarantined wheat diseases, wheat dwarf bunt spreads to cause distant outbreaks by seeds containing teliospores. In this study, based on a combination of amplicon sequencing and isolation approaches, we analyzed the seed microbiome signatures of endophytes between resistant and susceptible cultivars after infection with T. controversa. Among 310 bacterial species obtained only by amplicon sequencing and 51 species obtained only by isolation, we found 14 overlapping species by both methods; we detected 128 fungal species only by amplicon sequencing, 56 only by isolation, and 5 species by both methods. The results indicated that resistant uninfected cultivars hosted endophytic communities that were much more stable and beneficial to plant health than those in susceptible infected cultivars. The susceptible group showed higher diversity than the resistant group, the infected group showed more diversity than the uninfected group, and the microbial communities in seeds were related to infection or resistance to the pathogen. Some antagonistic microbes significantly suppressed the germination rate of the pathogen's teliospores, providing clues for future studies aimed at developing strategies against wheat dwarf bunt. Collectively, this research advances the understanding of the microbial assembly of wheat seeds upon exposure to fungal pathogen (T. controversa) infection. IMPORTANCE This is the first study on the microbiome signature of endophytes in wheat seed response to wheat dwarf bunt caused by Tilletia controversa Kühn. Some antagonistic microbes suppressed the germination of teliospores of the pathogen significantly, which will provide clues for future studies against wheat dwarf bunt. Collectively, this research first advances the understanding of the microbial assembly of wheat seed upon exposure to the fungal pathogen (T. controversa) infection.
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Basidiomycota , Triticum , Triticum/microbiologia , Endófitos/genética , Basidiomycota/genética , Sementes , Doenças das Plantas/microbiologiaRESUMO
Wheat (Triticum aestivum L.) diseases are major factors responsible for substantial yield losses worldwide, which affect global food security. For a long time, plant breeders have been struggling to improve wheat resistance against major diseases by selection and conventional breeding techniques. Therefore, this review was conducted to shed light on various gaps in the available literature and to reveal the most promising criteria for disease resistance in wheat. However, novel techniques for molecular breeding in the past few decades have been very fruitful for developing broad-spectrum disease resistance and other important traits in wheat. Many types of molecular markers such as SCAR, RAPD, SSR, SSLP, RFLP, SNP, and DArT, etc., have been reported for resistance against wheat pathogens. This article summarizes various insightful molecular markers involved in wheat improvement for resistance to major diseases through diverse breeding programs. Moreover, this review highlights the applications of marker assisted selection (MAS), quantitative trait loci (QTL), genome wide association studies (GWAS) and the CRISPR/Cas-9 system for developing disease resistance against most important wheat diseases. We also reviewed all reported mapped QTLs for bunts, rusts, smuts, and nematode diseases of wheat. Furthermore, we have also proposed how the CRISPR/Cas-9 system and GWAS can assist breeders in the future for the genetic improvement of wheat. If these molecular approaches are used successfully in the future, they can be a significant step toward expanding food production in wheat crops.
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BACKGROUND: To construct the Bifidobacterium infantis-mediated soluble kinase insert domain receptor (sKDR) prokaryotic expression system and to observe its inhibitory effect on growth of human umbilicus vessel endothelial cells (HUVECs) in vitro and Lewis lung cancer (LLC) on mice in vivo. METHODS: The Bifidobacterium infantis-mediated sKDR prokaryotic expression system was constructed through electroporation and subsequently identified through PCR and Western blot analysis. HUVECs were added to the products of this system to evaluate the anti-angiogenesis effect through MTT assay in vitro. The LLC mice models were divided into three groups: one group treated with saline (group a); one group treated with recombinant Bifidobacterium infantis containing pTRKH2-PsT plasmid group (group b); and one group treated with recombinant Bifidobacterium infantis containing pTRKH2-PsT/sKDR plasmid group (group c). The quality of life and survival of mice were recorded. Tumor volume, tumor weight, inhibitive rate, and necrosis rate of tumor were also evaluated. Necrosis of tumor and signals of blood flow in tumors were detected through color Doppler ultrasound. In addition, microvessel density (MVD) of the tumor tissues was assessed through CD31 immunohistochemical analysis. RESULTS: The positively transformed Bifidobacterium infantis with recombinant pTRKH2-PsT/sKDR plasmid was established, and was able to express sKDR at gene and protein levels. The proliferation of HUVECs cultivated with the extract of positively transformed bacteria was inhibited significantly compared with other groups (P < 0. 05). The quality of life of mice in group c was better than in group a and b. The recombinant Bifidobacterium infantis containing pTRKH2-PsT/sKDR plasmid enhanced the efficacy of tumor growth suppression and prolongation of survival, increased the necrosis rate of tumor significantly, and could obviously decrease MVD and the signals of blood flow in tumors. CONCLUSION: The Bifidobacterium infantis-mediated sKDR prokaryotic expression system was constructed successfully. This system could express sKDR at gene and protein levels and significantly inhibit the growth of HUVECs induced by VEGF in vitro. Moreover, it could inhibit tumor growth and safely prolong the survival time of LLC C57BL/6 mice.