scholarly journals Screening and Biochemical Characterization of Wheat Cultivars Resistance to Magnaporthe oryzae pv Triticum (MoT)

Author(s):  
Chandra Shekhar Biswas ◽  
Afsana Hannan ◽  
Abul Monsur ◽  
G H M Sagor

Global food security is seriously threatened due to increased frequency and occurrence of fungal diseases. One example is wheat blast caused by Magnaporthe oryzae is a fungal diseases of rice, wheat, and other grasses, that can destroy the whole food production to sustain millions of people. Wheat blast was first detected in february 2016 with a serious outbreak in Asia. Assessment of the available germplasms to stress tolerant/resistant is one of the best options for developing stress tolerant crop varieties. In this study, a total of sixteen wheat cultivars were collected and test their disease severity to blast pathogen Magnaporthe oryzae pv. Triticum (MoT). Among the varieties, BARI Gom 33 exhibited partially resistance against blast pathogen, whereas all other genotypes become susceptible to MoT. Different yield and yield contributing characters of both resistant and susceptible cultivars were also evaluated and found no significant differences among them. To understand the underlying mechanism of resistance in BARI Gom 33, antioxidant enzyme activity, concentration of reactive oxygen species and cellular damage after fungal infection were also evaluated and found that activities of ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) were higher in BARI Gom 33 than BARI Gom 25 and BARI Gom 31. The hydrogen peroxide (H2O2) and malondealdehyde (MDA) content in BARI Gom 33 was low compare to BARI Gom 25 and BARI Gom 31, which may due to greater increase of the APX, CAT and POD in resistant genotypes. Thus, it may suggest that a more efficient antioxidative defense system in BARI Gom 33 during the infection process of M. oryzae restricts the cell damage caused by the fungus. The identified genotypes can either be used directly in the blast prone area or as a source of resistance to further development of blast resistance high yielding wheat variety.

2016 ◽  
Vol 17 (3) ◽  
pp. 186-187 ◽  
Author(s):  
C. D. Cruz ◽  
W. W. Bockus ◽  
J. P. Stack ◽  
B. Valent ◽  
J. N. Maciel ◽  
...  

Wheat blast, caused by the Triticum pathotype of Magnaporthe oryzae, poses a significant threat to wheat production worldwide. Because this pathotype does not occur in the United States, it is important to prepare for its possible introduction. As part of this preparation, over 500 U.S. wheat cultivars were tested for susceptibility or resistance to head blast. Inoculations were conducted under biosafety level 3 conditions. However, the protocols to phenotype wheat cultivars vary among researchers, and head blast inoculation protocols need to be standardized so that results can be easily interpreted and shared internationally. The protocol presented, based on several years' experience, is recommended for common use to facilitate direct comparison of disease phenotyping results among researchers. Accepted for publication 12 August 2016.


2019 ◽  
Vol 17 (2) ◽  
pp. 122-132
Author(s):  
M. Thoihidul Islam ◽  
Mohammad Rashid Arif ◽  
Lutful Hassan ◽  
Arif Hasan Khan Robin

Fearsome wheat blast disease expanded its radius from Latin America to Bangladesh in 2016 with higher degrees of destruction efficiency. In 1985, Brazil was the first hotspot and consecutively Paraguay, Argentina, Bolivia were affected by the wheat blast fungus. Blast fungus Magnaporthe oryzae is under pyriculariaceae family with three-celled, pyriform, hyaline conidia. Not only wheat and rice are affected by the blast pathogen but also around 50 grass species can be affected and act as host, but the fungus pathotype is specific and distinct for each plant species. Morpho-biometrical analysis revealed similarity between the Magnaporthe oryzae pathotype Tritici (MoT) strain of Bangladeshi and Brazil. Through extensive molecular genetics and genomics study unfolded five resistant genes, among those Rmg2, Rmg3, and Rmg7 lost viability but Rmg8 and RmgGR119 still have resistance. In addition, 2NS translocation from Aegilops ventricosa in wheat reports resistance against MoT. CIMMYT based Milan variety is regarded as a resistant variety and plant breeders are trying to develop new resistant varieties. But the main problem regarding blast pathogen is breakdown of resistance and evolving virulent races consecutively which is fueled by global warming. A wide range of molecular markers can potentially be used for blast resistance study. Utilization of medium to high-throughput markers like SSR, InDel and SNP gave pace in blast resistance study. Along with that, allele mining has potentiality for finding out source of resistance. In addition, gene pyramiding will play a vital role in introgression of multiple resistant genes into a superior wheat linage. In future, high-throughput marker technology along with cutting-edge gene editing technology will play a pivotal role. Furthermore, the collaborative research in Bangladesh indicates that international scientific community has taken wheat blast as a serious issue. J. Bangladesh Agril. Univ. 17(2): 122–132, June 2019


2014 ◽  
Vol 104 (1) ◽  
pp. 95-107 ◽  
Author(s):  
João L. Nunes Maciel ◽  
Paulo C. Ceresini ◽  
Vanina L. Castroagudin ◽  
Marcelo Zala ◽  
Gerrit H. J. Kema ◽  
...  

Since its first report in Brazil in 1985, wheat blast, caused by Magnaporthe oryzae (anamorph: Pyricularia oryzae), has become increasingly important in South America, where the disease is still spreading. We used 11 microsatellite loci to elucidate the population structure of the wheat blast pathogen in wheat fields in central-western, southeastern, and southern Brazil. No subdivision was found among the wheat-infecting populations, consistent with high levels of gene flow across a large spatial scale. Although the clonal fraction was relatively high and the two mating type idiomorphs (MAT1-1 and MAT1-2) were not at similar frequencies, the clone-corrected populations from Distrito Federal and Goiás, Minas Triangle, and São Paulo were in gametic equilibrium. Based on these findings, we propose that populations of the wheat blast pathogen exhibit a mixed reproductive system in which sexual reproduction is followed by the local dispersal of clones. Seedling virulence assays with local wheat cultivars differentiated 14 pathotypes in the current population. Detached head virulence assays differentiated eight virulence groups on the same wheat cultivars. There was no correlation between seedling and head reactions.


2021 ◽  
pp. PHP-11-20-0101-
Author(s):  
Barbara Valent ◽  
Giovana Cruppe ◽  
James P. Stack ◽  
C. D. Cruz ◽  
Mark L. Farman ◽  
...  

Wheat blast is an explosive new fungal disease of wheat caused by an Magnaporthe oryzae (synonym of Pyricularia oryzae) host-adapted subpopulation, the M. oryzae Triticum pathotype (MoT). MoT has been found in South America, South Asia, and Africa, but not in the United States. Wheat blast caused by the MoT fungus was first reported in Brazil in 1985 and subsequently spread to Bolivia, Paraguay, and Argentina in the 1990s and 2000s. The disease first appeared in Bangladesh in 2016 and in Zambia in 2017. The MoT fungus is seedborne, and the most likely route for movement across oceans was though grain trade. Wheat head (spike) blast is the predominant form of the disease in the field, although foliar and stem blast also occurs. The disease has proven hard to control when weather conditions are conducive, often resulting in devastating yield and quality losses. The only currently effective resistance, contained in the 2NvS translocation from the wild wheat relative Aegilops ventricosa, confers partial resistance that is variable depending on the genetic background of the specific wheat variety. Fungicides are not fully effective in controlling wheat head blast if warm, humid weather occurs during the heading stage. A major disease management strategy in areas where the disease occurs involves timing the wheat planting date so that heading does not coincide with warm rainy weather. A climate suitability model for the United States indicates that all of U.S. soft red winter wheat and about half of the hard red winter wheat are at risk.


2020 ◽  
Vol 20 (7) ◽  
pp. 1010-1014 ◽  
Author(s):  
Dana Filatova ◽  
Christine Cherpak

Background: Hypersensitivity to nickel is a very common cause of allergic contact dermatitis since this metal is largely present in industrial and consumer products as well as in some commonly consumed foods, air, soil, and water. In nickel-sensitized individuals, a cell-mediated delayed hypersensitivity response results in contact to dermatitis due to mucous membranes coming in long-term contact with nickel-containing objects. This process involves the generation of reactive oxidative species and lipid peroxidation-induced oxidative damage. Immunologically, the involvement of T helper (h)-1 and Th-2 cells, as well as the reduced function of T regulatory cells, are of importance. The toxicity, mutagenicity, and carcinogenicity of nickel are attributed to the generation of reactive oxygen species and induction of oxidative damage via lipid peroxidation, which results in DNA damage. Objective: The aim of this research is to identify nutritionally actionable interventions that can intercept nickel-induced cell damage due to their antioxidant capacities. Conclusion: Nutritional interventions may be used to modulate immune dysregulation, thereby intercepting nickel-induced cellular damage. Among these nutritional interventions are a low-nickel diet and an antioxidant-rich diet that is sufficient in iron needed to minimize nickel absorption. These dietary approaches not only reduce the likelihood of nickel toxicity by minimizing nickel exposure but also help prevent oxidative damage by supplying the body with antioxidants that neutralize free radicals.


Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 301
Author(s):  
Vishesh Kumar ◽  
Priyanka Jain ◽  
Sureshkumar Venkadesan ◽  
Suhas Gorakh Karkute ◽  
Jyotika Bhati ◽  
...  

Rice blast is a global threat to food security with up to 50% yield losses. Panicle blast is a more severe form of rice blast and the response of rice plant to leaf and panicle blast is distinct in different genotypes. To understand the specific response of rice in panicle blast, transcriptome analysis of blast resistant cultivar Tetep, and susceptible cultivar HP2216 was carried out using RNA-Seq approach after 48, 72 and 96 h of infection with Magnaporthe oryzae along with mock inoculation. Transcriptome data analysis of infected panicle tissues revealed that 3553 genes differentially expressed in HP2216 and 2491 genes in Tetep, which must be the responsible factor behind the differential disease response. The defense responsive genes are involved mainly in defense pathways namely, hormonal regulation, synthesis of reactive oxygen species, secondary metabolites and cell wall modification. The common differentially expressed genes in both the cultivars were defense responsive transcription factors, NBS-LRR genes, kinases, pathogenesis related genes and peroxidases. In Tetep, cell wall strengthening pathway represented by PMR5, dirigent, tubulin, cell wall proteins, chitinases, and proteases was found to be specifically enriched. Additionally, many novel genes having DOMON, VWF, and PCaP1 domains which are specific to cell membrane were highly expressed only in Tetep post infection, suggesting their role in panicle blast resistance. Thus, our study shows that panicle blast resistance is a complex phenomenon contributed by early defense response through ROS production and detoxification, MAPK and LRR signaling, accumulation of antimicrobial compounds and secondary metabolites, and cell wall strengthening to prevent the entry and spread of the fungi. The present investigation provided valuable candidate genes that can unravel the mechanisms of panicle blast resistance and help in the rice blast breeding program.


2021 ◽  
Author(s):  
S.I. Martinez ◽  
A. Wegner ◽  
S. Bohnert ◽  
U. Schaffrath ◽  
A. Perello

2020 ◽  
Vol 71 (1) ◽  
pp. 435-460 ◽  
Author(s):  
Melvin J. Oliver ◽  
Jill M. Farrant ◽  
Henk W.M. Hilhorst ◽  
Sagadevan Mundree ◽  
Brett Williams ◽  
...  

Desiccation of plants is often lethal but is tolerated by the majority of seeds and by vegetative tissues of only a small number of land plants. Desiccation tolerance is an ancient trait, lost from vegetative tissues following the appearance of tracheids but reappearing in several lineages when selection pressures favored its evolution. Cells of all desiccation-tolerant plants and seeds must possess a core set of mechanisms to protect them from desiccation- and rehydration-induced damage. This review explores how desiccation generates cell damage and how tolerant cells assuage the complex array of mechanical, structural, metabolic, and chemical stresses and survive.Likewise, the stress of rehydration requires appropriate mitigating cellular responses. We also explore what comparative genomics, both structural and responsive, have added to our understanding of cellular protection mechanisms induced by desiccation, and how vegetative desiccation tolerance circumvents destructive, stress-induced cell senescence.


2014 ◽  
Vol 34 (8) ◽  
pp. 848-855 ◽  
Author(s):  
I Hwang ◽  
JW Lee ◽  
JS Kim ◽  
HW Gil ◽  
HY Song ◽  
...  

Objective: Self-poisoning with (4-chloro-2-methylphenoxy) acetic acid (MCPA) is a common reason for presentation to hospitals, especially in some Asian countries. We encountered a case of a 76-year-old woman who experienced unconsciousness, shock and respiratory failure after ingesting 100 mL MCPA herbicide. We determined whether the surfactant in the formulation was the chemical responsible for the toxic symptom in this patient. Design: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability and lactate dehydrogenase (LDH) cytotoxicity assays were performed on human brain neuroblastoma SK-N-SH cells. The expressions of 84 genes in 9 categories that are implicated in cellular damage pathways were quantified using an RT2 Profiler™ PCR array on a human neuronal cell line challenged with polyoxyethylene tridecyl ether (PTE). Setting: Pesticide intoxication institute in university hospital. Interventions: Extracorporeal elimination with intravenous lipid emulsion. Measurements: Cell viability and gene expression. Main Results: In the MTT assay, MCPA only minimally decreased cell viability even at concentrations as high as 1 mM. Cells treated with 1-methoxy-2-propanol, dimethylamine and polypropylene glycol exhibited minimal decreases in viability, whilst the viability of cells challenged with PTE decreased dramatically; only 15.5% of cells survived after exposure to 1 µM PTE. Similarly, the results of the LDH cytotoxicity assay showed that MCPA had very low cytotoxicity, whilst cells treated with PTE showed incomparably higher LDH levels ( p < 0.0001). PTE up-regulated the expressions of genes implicated in various cell damage pathways, particularly genes involved in the inflammatory pathway. Conclusions: The surfactant PTE was likely the chemical responsible for the toxic symptom in our patient.


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