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OsLYP4 and OsLYP6 play critical roles in rice defense signal transduction

OsLYP4 and OsLYP6 play critical roles in rice defense signal transduction | Rice Blast | Scoop.it

Here we further demonstrated the important roles of OsLYP4 and OsLYP6 in rice defense signaling, as silencing of either LYP impaired the defense marker gene activation induced by either bacterial pathogen Xanthomonas oryzaecola or fungal pathogen Magnaporthe oryzae. Moreover, we found that OsLYP4 and OsLYP6 could form homo- and hetero-dimers, and could interact with CEBiP, suggesting an unexpected complexity of chitin perception in rice

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Rice Blast
Scientific articles on rice blast and wheat blast 20 new articles each month !
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Infected rice residues allowing long term survival of blast pathogen serve as major source of primary inoculum in high altitude upland ecology

Magnaporthe oryzae is the fungal plant pathogen which causes rice blast. The sources of primary inoculum and overwintering mode of the fungus remain largely unknown. The effect of rice residues on the onset of blast epidemics and the potential of survival of M. oryzae in the residues were studied in upland conditions in Madagascar. Blast disease was observed in a three-year field experiment in three treatments: with infected rice residues on the soil surface, with uninfected rice residues on the soil surface, and without rice residues. Leaf blast incidence was significantly higher in the treatment with infected rice residues than in the two other treatments at the early stages of the epidemic. In a second set of trials, the survival of M. oryzae on rice residues was monitored. Infected rice stems were placed by lots in three places: on the mulch of rice residues, under the mulch, and buried at a depth of 10 cm in the soil. Each month, samples were taken from the field and tested for sporulation. The survival of the blast fungus decreased rapidly on the stems buried in the soil but remained high for the other conditions. Sporulation of the fungus was observed on stems left on the mulch for up to18 months. We concluded that in field conditions, the presence of infected rice residues could initiate an epidemic of blast. The results of this study may help designing effective management strategies for rice residues infected by M. oryzae.
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Equol, a Clinically Important Metabolite, Inhibits the Development and Pathogenicity of Magnaporthe oryzae, the Causal Agent of Rice Blast Disease

Equol, a Clinically Important Metabolite, Inhibits the Development and Pathogenicity of Magnaporthe oryzae, the Causal Agent of Rice Blast Disease | Rice Blast | Scoop.it
Equol, a metabolite of soybean isoflavone daidzein, has been proven to have various bioactivities related to human health, but little is known on its antifungal activity to plant fungal pathogens. Magnaporthe oryzae is a phytopathogenic fungus that causes rice blast, a devastating disease on rice. Here, we demonstrated that equol influences the development and pathogenicity of M. oryzae. Equol showed a significant inhibition to the mycelial growth, conidial generation and germination, and appressorial formation of M. oryzae. As a result, equol greatly reduced the virulence of M. oryzae on rice and barley leaves. The antifungal activity of equol was also found in several other plant fungal pathogens. These findings expand our knowledge on the bioactivities of equol.
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Current understanding of pattern-triggered immunity and hormone-mediated defense in rice (Oryza sativa) in response to Magnaporthe oryzae infection

Current understanding of pattern-triggered immunity and hormone-mediated defense in rice (Oryza sativa) in response to Magnaporthe oryzae infection | Rice Blast | Scoop.it
Plant pathogens represent a huge threat to world food security, affecting both crop production and quality. Although significant progress has been made in improving plant immunity by expressing key, defense-related genes and proteins from different species in transgenic crops, a challenge remains for molecular breeders and biotechnologists to successfully engineer elite, transgenic crop varieties with improved resistance against critical plant pathogens. Upon pathogen attack, including infection of rice (Oryza sativa) by Magnaporthe oryzae, host plants initiate a complex defense response at molecular, biochemical and physiological levels. Plants perceive the presence of pathogens by detecting microbe-associated molecular patterns via pattern recognition receptors, and initiate a first line of innate immunity, the so-called pattern-triggered immunity (PTI). This results in a series of downstream defense responses, including the production of hormones, which collectively function to fend off pathogen attacks. A variety of studies have demonstrated that many genes are involved in the defense response of rice to M. oryzae. In this review, the current understanding of mechanisms that improve rice defense response to M. oryzae will be discussed, with special focus on PTI and the phytohormones ethylene, jasmonic acid, salicylic acid, and abscisic acid; as well as on the mediation of defense signaling mechanisms by PTI and these hormones. Potential target genes that may serve as promising candidates for improving rice immunity against M. oryzae will also be discussed.
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Graphical Genotype of KDML105xIR64 Backcross Lines Exhibited Rice Blast Resistance - Chiang Mai Journal of Science

Graphical Genotype of KDML105xIR64 Backcross Lines Exhibited Rice Blast Resistance - Chiang Mai Journal of Science | Rice Blast | Scoop.it
The rice blast resistance is an important characteristic to ensure stability in rice production. It protects the plant from the infection of rice blast fungus (Magnaporthe oryzae), the major concerned pathogen in every rice-growing country. In this study, graphical genotypes of 3 selected BC2F7 lines with blast resistant phenotype, derived from IR64 genome on the background genome of Thai jasmine rice, KDML105, were constructed. A total of 110 DNA markers (97 SSR and 13 InDel markers) were used to characterize the genetic makeup of the selected BC2F7 lines. The graphical genotype of the 3 selected backcross lines revealed that the majority of genetic background in backcross lines derived from KDML105 and small segments from IR64. These small genetic differences in backcross lines can result in large differences in rice blast resistant spectrum. Regions on chromosomes linked to molecular markers appear to be important loci governing blast resistance are as follows - Pi-kd/Pi-b on chromosome 2 at RM208, Pi-27(t) and Pi-zt on chromosome 6, and R-QTL on chromosome 9. In conclusion, the information obtained from our study indicating that this set of BC2F7 could be used as the donor in rice blast resistance breeding program.
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Comparative analysis of the genome of the field isolate V86010 of the rice blast fungus Magnaporthe oryzae from Philippines - ScienceDirect

Genome dynamics of pathogenic organisms are driven by plant host and pathogenic organism co-evolution, in which pathogen genomes are used to overcome stresses imposed by hosts with various genetic backgrounds through generation of a range of field isolates. This model also applies to the rice host and its fungal pathogen Magnaporthe oryzae. To better understand genetic variation of M. oryzae in nature, the field isolate V86010 from the Philippines was sequenced and analyzed. Genome annotation found that the assembled V86010 genome was composed of 1 931 scaffolds with a combined length of 38.9 Mb. The average GC ratio is 51.3% and repetitive elements constitute 5.1% of the genome. A total of 11 857 genes including 616 effector protein genes were predicted using a combined analysis pipeline. All predicted genes and effector protein genes of isolate V86010 distribute on the eight chromosomes when aligned with the assembled genome of isolate 70-15. Effector protein genes are located disproportionately at several chromosomal ends. The Pot2 elements are abundant in V86010. Seven V86010-specific effector proteins were found to suppress programmed cell death induced by BAX in tobacco leaves using an Agrobacterium-mediated transient assay. Our results may provide useful information for further study of the molecular and genomic dynamics in the evolution of M. oryzae and rice host interactions, and for characterizing novel effectors and AVR genes in the rice blast pathogen.
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Proteomic analyses of Magnaporthe oryzae development disrupted by salicylic acid

Proteomic analyses of Magnaporthe oryzae development disrupted by salicylic acid | Rice Blast | Scoop.it
Salicylic acid (SA) known as a plant hormone plays an important role in induced systemic resistance and hypersensitive cells, effectively in responses against abiotic stresses such as drought, cold, heavy metal toxicity, and osmotic stress as well. Magnaporthe oryzae is the causal agent of rice blast disease that causes losses of rice yield provided for 60 million people. However, little is known about fungal response to exogenous SA. We observed that 100 μM of SA exhibited higher inhibitory effects on mycelium development, conidiation, conidial germination and appressorium formation in present study. To reveal the involved pathway underlying, comparative proteomes were performed. The results show that the proteins involving energy metabolism, fungal development, signal transition, stress and pathogenicity related proteins were reprogrammed by SA with concentrations of 100 μM. Our results indicate that SA not only improves rice growth, but it also disrupts development of blast fungus.
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Photosynthesis impairments and excitation energy dissipation on wheat plants supplied with silicon and infected with Pyricularia oryzae - ScienceDirect

Photosynthesis impairments and excitation energy dissipation on wheat plants supplied with silicon and infected with Pyricularia oryzae - ScienceDirect | Rice Blast | Scoop.it
Photosynthetic pigments, mainly lutein, were lower on plants non-supplied with Si in contrast to Si-supplied plants.


Reductions on A/PAR, Fv/Fm, ΦPSII and ETR were greater on leaves of plants non-supplied with Si.

More carotenoids on leaves of Si-supplied plants reduced losses on light energy dissipation caused by fungal infection.
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41st New Phytologist Symposium

41st New Phytologist Symposium | Rice Blast | Scoop.it
On behalf of the New Phytologist Trust and symposium organisers, I am pleased to invite you to a symposium entitled 'Plant sciences for the future', to be held at Présidence de l’Université de Lorraine, Nancy, France, 11–13 April 2018. The symposium is jointly funded by the New Phytologist Trust and Labex ARBRE.
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Host-Induced Gene Silencing of Rice Blast Fungus Magnaporthe oryzae Pathogenicity Genes Mediated by the Brome Mosaic Virus

Host-Induced Gene Silencing of Rice Blast Fungus Magnaporthe oryzae Pathogenicity Genes Mediated by the Brome Mosaic Virus | Rice Blast | Scoop.it
Magnaporthe oryzae is a devastating plant pathogen, which has a detrimental impact on rice production worldwide. Despite its agronomical importance, some newly-emerging pathotypes often overcome race-specific disease resistance rapidly. It is thus desirable to develop a novel strategy for the long-lasting resistance of rice plants to ever-changing fungal pathogens. Brome mosaic virus (BMV)-induced RNA interference (RNAi) has emerged as a useful tool to study host-resistance genes for rice blast protection. Planta-generated silencing of targeted genes inside biotrophic pathogens can be achieved by expression of M. oryzae-derived gene fragments in the BMV-mediated gene silencing system, a technique termed host-induced gene silencing (HIGS). In this study, the effectiveness of BMV-mediated HIGS in M. oryzae was examined by targeting three predicted pathogenicity genes, MoABC1, MoMAC1 and MoPMK1. Systemic generation of fungal gene-specific small interfering RNA (siRNA) molecules induced by inoculation of BMV viral vectors inhibited disease development and reduced the transcription of targeted fungal genes after subsequent M. oryzae inoculation. Combined introduction of fungal gene sequences in sense and antisense orientation mediated by the BMV silencing vectors significantly enhanced the efficiency of this host-generated trans-specific RNAi, implying that these fungal genes played crucial roles in pathogenicity. Collectively, our results indicated that BMV-HIGS system was a great strategy for protecting host plants against the invasion of pathogenic fungi.
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Enhanced resistance to rice blast and sheath blight in rice (oryza sativa L.) by expressing the oxalate decarboxylase protein Bacisubin from Bacillus subtilis - ScienceDirect

Enhanced resistance to rice blast and sheath blight in rice (oryza sativa L.) by expressing the oxalate decarboxylase protein Bacisubin from Bacillus subtilis - ScienceDirect | Rice Blast | Scoop.it

We identified an oxalate decarboxylase gene from Bacillus subtilis.
We generated the transgenic rice lines containing the OxDC gene sucussfully.
The transgenic rice lines showed enhanced resistance to the rice blast and sheath blight.
Glutaredoxin and MADS box encoding genes may be involved in OxDC possible mechanism in resistance to rice disease.

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In vitro evaluation of bio-agents against Pyricularia oryzae (Cav.) causing rice blast disease

The five different bio-agents viz., Trichoderma viride, T. harzianum, T. virens, Pseudomonas fluorescens and Bacillus subtilis were evaluated against Pyricularia oryzae at four and eight days after incubation through dual culture technique. Among the five different bio-agents, highest per cent inhibition of mycelial growth of fungus was recorded in T. virens i.e. 67 per cent and 70 percent after four and eight days after incubation respectively with mean of 68.5 per cent followed by Trichoderma viride with the inhibition of 61 and 63 per cent respectively with mean of 62 per cent. The Pseudomonas fluorescens did not show any inhibition of mycelial growth of P. oryzae as the pathogen over grew the bio-agents.
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Co-transformation mediated stacking of blast resistance genes Pi54 and Pi54rh in rice provides broad spectrum resistance against Magnaporthe oryzae

Co-transformation mediated stacking of blast resistance genes Pi54 and Pi54rh in rice provides broad spectrum resistance against Magnaporthe oryzae | Rice Blast | Scoop.it
This is the first report of stacking two major blast resistance genes in blast susceptible rice variety using co-transformation method to widen the resistance spectrum against different isolates of Magnaporthe oryzae.
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Plant immunity under abiotic stress

Plant immunity under abiotic stress | Rice Blast | Scoop.it

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Stress2TF: a manually curated database of TF regulation in plant response to stress - ScienceDirect

Stress2TF: a manually curated database of TF regulation in plant response to stress - ScienceDirect | Rice Blast | Scoop.it
We presented a manually curated database of TF regulation in plant response to stress.


Currently, Stress2TF documented 1533 stress-TF regulatory relationships.


Stress2TF provides detailed information for each stress-TF regulatory entry.


Stress2TF will be regularly updated and released in the life community.
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Evaluation of rhizobacteria in upland rice in Brazil: growth promotion and interaction of induced defense responses against leaf blast (Magnaporthe oryzae)

Blast and the initial vigor of upland rice plants are the main challenges facing rice crops in Brazilian no-tillage systems. The aim of this study was to evaluate the growth promotion and interactions of defense responses against Magnaporthe oryzae in rice plants treated with rhizobacteria Bacillus sp. (BRM 32110) and Serratia sp. (BRM 32114). The seeds of the rice were microbiolized, and 14 days after the plants emerged, the soil was drenched with rhizobacterial suspensions. Growth promotion was evaluated by root and shoot biomass, root and shoot length, foliar area, and nitrate reductase (NR) activity. The defense response was evaluated by quantification of the rice blast severity (RBS), disease progress, pathogenesis-related protein (PRP) activity, and salicylic acid content (SA). The length and biomass of the roots and shoots and the foliar area of the plants treated with BRM 32114 isolate increased; however, the NR activity was 43% lower compared to the control. Both isolates reduced the severity and progress of the disease. Principal component analysis showed that RBS, β-1,3-glucanase (GLU), peroxidase (POX), and phenylalanine ammonia lyase (PAL) were the main sources of the first components of variance, whereas lipoxygenase (LOX) and SA were the main sources of the second components and were negatively correlated. Serratia sp. isolate BRM 32114 can be used as a growth-promoting agent and has potential for inducing resistance in rice plants. The results suggest that the interaction among the levels and timing of the PRP activity and the levels of SA play important roles in the defense responses against M. oryzae.
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Standardized rosemary extract induces host plant defenses and suppresses rice leaf blast

The efficiency of rosemary (Rosmarinus officinalis L.) liquid extract (RLE), standardized as rosmarinic acid (RA) on the suppression of rice (Oryza sativa) leaf blast (Magnaporthe oryzae) (LB) were determinate. RLE (3.3, 6.6, and 10 mg·mL−1), SRA (3.1, 4.2, and 6.3 mg·mL−1), and water (control) were sprayed on leaves of Primavera rice cultivar, at 48 hours before inoculation with M. oryzae (MO). The activities of chitinase, β-1, 3-glucanase, peroxidase, lipoxygenase, phenylalanine ammonia-lyase, and phenolic compounds and of salicylic acid levels were determined in samples collected before and after inoculation with MO. The highest concentrations of RLE and RA reduced the LB severity by more than 92%. Except for Peroxidase, all enzymes increased their activity after spraying RLE and RA, prior and after the challenge inoculation. Our results suggest that RLE standardized as RA can induce the activity of enzymes related to plant defense.
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Genetic Improvement of Rice (Oryza sativa L.)

Genetic Improvement of Rice (Oryza sativa L.) | Rice Blast | Scoop.it
The emerging challenges of increasing global population, decreasing arable lands, and escalating threats posed by climate change exert pressure on the genetic improvement of rice to increase its yield potential in irrigated and nonirrigated lands as it is the staple food of more than three billion people. Advances in genetics and molecular biology have enabled scientists to use yield-enhancing functional genes for rice genetic improvement. Recently, SNP markers associated with major yield-enhancing functional genes have been used to develop breeding lines with 9–32% yield increase over the check variety. New methods to identify high yield-expressing genes and to transfer these genes into different elite cultivars are continuously being developed to increase rice production and productivity. Additional genetic resources have also been identified from the nearest wild relatives. Resistance genes lost during the domestication process of rice and their pyramids are being transferred into elite rice cultivars to make the future rice cultivars genetically resistant to biotic stresses and tolerant to abiotic stresses. Promising methods are being developed toward the genetic improvement of rice by pyramiding genes for yield potential as well as resistance to biotic and abiotic stresses. Significant progress has been achieved at IRRI by enriching rice grain with provitamin A (b-carotene) and bio-fortification of iron and zinc. Bioavailability of these micronutrients will provide benefit to poor rice consumers, particularly in Asia to overcome the problems of vitamin A, iron, and zinc deficiency in their diet.
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Effects of UV-B radiation on the infectivity of Magnaporthe oryzae and rice disease-resistant physiology in Yuanyang terraces - Photochemical & Photobiological Sciences (RSC Publishing)

Effects of UV-B radiation on the infectivity of Magnaporthe oryzae and rice disease-resistant physiology in Yuanyang terraces - Photochemical & Photobiological Sciences (RSC Publishing) | Rice Blast | Scoop.it
The traditional rice variety “Baijiaolaojing” was planted in Yuanyang terraces (1600 m altitude) under field conditions. The effects of enhanced UV-B radiation (0 kJ m−2, 2.5 kJ m−2, 5.0 kJ m−2 and 7.5 kJ m−2) on the rice–Magnaporthe oryzae system were studied with respect to the Magnaporthe oryzae infection, the disease-resistance physiology of the rice and the rice blast disease condition. The results showed that under enhanced UV-B radiation, the infectivity of Magnaporthe oryzae was decreased, which could significantly inhibit its growth and sporulation. The activities of rice leaf disease-resistance-related enzymes (phenylalanine ammonia-lyase, lipoxygenase, chitinase and β-1,3-glucanase) were significantly increased under enhanced UV-B radiation. Following inoculation with Magnaporthe oryzae, levels of disease-resistance-related substances in the rice leaves were significantly increased. Among the results, it was found that leaves after UV-B radiation had a more significant resistance response. The level of UV-B irradiation showed a parabolic relationship with the rice blast index (r2 = 0.85, P < 0.01; in the control group, r2 = 0.88, P < 0.01). The disease index decreased with increase in irradiation. The DI was at a minimum with enhanced UV-B irradiance of 4 kJ m−2; thereafter, it increased with increasing irradiation. The enhanced UV-B radiation had a direct impact on the growth of rice and Magnaporthe oryzae, and it indirectly changed the rice–Magnaporthe oryzae system. UV-B radiation could reduce the harmful impact of rice blast.
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Large-scale identification of lysine acetylated proteins in vegetative hyphae of the rice blast fungus

Large-scale identification of lysine acetylated proteins in vegetative hyphae of the rice blast fungus | Rice Blast | Scoop.it
Lysine acetylation is a major post-translational modification that plays important regulatory roles in diverse biological processes to perform various cellular functions in both eukaryotes and prokaryotes. However, roles of lysine acetylation in plant fungal pathogens were less studied. Here, we provided the first lysine acetylome of vegetative hyphae of the rice blast fungus Magnaporthe oryzae through a combination of highly sensitive immune-affinity purification and high-resolution LC-MS/MS. This lysine acetylome had 2,720 acetylation sites in 1,269 proteins. The lysine acetylated proteins were involved indiverse cellular functions, and located in 820 nodes and 7,709 edges among the protein-protein interaction network. Several amino acid residues nearby the lysine acetylation sites were conserved, including KacR, KacK, and KacH. Importantly, dozens of lysine acetylated proteins are found to be important to vegetative hyphal growth and fungal pathogenicity. Taken together, our results provided the first comprehensive view of lysine acetylome of M.oryzae and suggested protein lysine acetylation played important roles to fungal development and pathogenicity.
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How alkalinization drives fungal pathogenicity

How alkalinization drives fungal pathogenicity | Rice Blast | Scoop.it
pH governs most, if not all, processes of life. In fungi, ambient pH acts as a potent regulator of growth and development [1]. Studies conducted primarily in the 2 model organisms Saccharomyces cerevisiae and Aspergillus nidulans have cemented our understanding of how fungi sense and respond to pH. More recently, pH has emerged as a key player in the control of fungal pathogenicity. Infections caused by fungi are often associated with a pH shift in the surrounding host tissue [2–4]. Extracellular alkalinization contributes to fungal virulence, but the underlying mechanisms are not fully understood. Recent studies have revealed new and unexpected ways by which fungi induce host alkalinization to increase their infectious potential. Here, we provide a brief overview of the mechanisms that govern pH signaling in fungi and highlight how recent findings have advanced our understanding of pathogen-induced alkalinization and its role during infection. We also discuss the emerging view that intracellular pH (pHi) acts as a master switch to govern fungal development and pathogenicity.
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Cross Infection between Rice and Wheat Blast Pathogen Pyricularia oryzae | Monsur | Bangladesh Rice Journal

Cross infection between rice and wheat blast fungi was investigated in a series of experiments conducted under controlled glasshouse condition following a completely randomized design. Two rice (BRRI dhan29 and LTH) and two wheat (BARI Gom25 and BARI Gom26) varieties were grown in plastic trays as sole and rice-wheat mixed crop culture. Plants were artificially inoculated using virulent isolates of rice and wheat blast fungi. It was observed that irrespective of variety and crop culture technique, all the isolates of wheat blast fungus caused significant 100% plant infection on leaf typical leaf blast symptoms appeared on wheat seedlings but no blast symptom on rice. Conversely, the test-isolates of rice blast fungus did not produce any disease reaction on wheat seedlings, though leaf blast was observed on 100% rice plants. Therefore, we conclude that rice blast pathogen population is different from those of wheat blast pathogen (Pyricularia oryzae).
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HvPap-1 C1A Protease Participates Differentially in the Barley Response to a Pathogen and an Herbivore

Co-evolutionary processes in plant–pathogen/herbivore systems indicate that protease inhibitors have a particular value in biotic interactions. However, little is known about the defensive role of their targets, the plant proteases. C1A cysteine proteases are the most abundant enzymes responsible for the proteolytic activity during different processes like germination, development and senescence in plants. To identify and characterize C1A cysteine proteases of barley with a potential role in defense, mRNA and protein expression patterns were analyzed in response to biotics stresses. A barley cysteine protease, HvPap-1, previously related to abiotic stresses and grain germination, was particularly induced by flagellin or chitosan elicitation, and biotic stresses such as the phytopathogenic fungus Magnaporthe oryzae or the phytophagous mite Tetranychus urticae. To elucidate the in vivo participation of this enzyme in defense, transformed barley plants overexpressing or silencing HvPap-1 encoding gene were subjected to M. oryzae infection or T. urticae infestation. Whereas overexpressing plants were less susceptible to the fungus than silencing plants, the opposite behavior occurred to the mite. This unexpected result highlights the complexity of the regulatory events leading to the response to a particular biotic stress.
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"Characterization of the interaction between the bacterium TR3 and Magn" by Xue Zhang

Rice blast disease caused by the filamentous ascomycete Magnaporthe oryzae, is one of the most destructive diseases that affect global rice production and food security. Bacteria have been explored and developed as biological control agents (Walsh, Morrissey et al. 2001). Pseudomonas syringae pv. tomato (Pst) DC3000 delivers effector proteins into plant cells by the bacterial type III secretion system (T3SS). Some of these P. syringae effectors target fundamental cellular processes that are conserved among eukaryotes. Heterologous expression of bacterial type III effectors (T3Es) HopAI manipulates the conserved cell pathway, MAPK signaling pathway in M. oryzae, which indicates T3E HopAI maintained its targets and the mode of action in evolutionary distant organisms. Moreover, M. oryzae may be used to characterize the T3Es function. HopAI is a phosphothreonine lyase that possesses the same in vitro catalytic activity as OspF and SpvC on Erk2 MAP kinases. In this study, we expressed two T3SS effectors HopAI and HopI1 from DC3000 in the rice blast fungus M. oryzae. Expression of HopAI resulted in defects in conidiation and hyphae growth similar to those of the ?mps1 mutant. The phosphorylation level of Mps1 also was reduced in the HopAI transformants. Co- immunoprecipitation assays confirmed the physical interaction of Mps1 with HopAI, and Pmk1 also weakly interacted with HopAI. To understand the role of Mps1 during invasive growth, we expressed HopAI under the promoter of the MIR1 or BAS1 gene that specifically expressed at the infectious stage. In rice leaf sheath penetration assays, the PBAS1- or PMIR1-HopAI transformants were defective in invasive growth, indicating that MAPK signaling is important for cell-to-cell movement of infectious hyphae. The Bas1-GFP and Bas4-GFP fusion proteins in the PMIR1-HopAI transformants were not detected, which indicates that the expression of HopAI in invasive hyphae may play a role in fungal effectors localization or expression. Attachment with host cells is critical for T3SS activation of secretion (Notti and Stebbins 2016). To further characterize the interaction between the bacterium and M. oryzae, seven bacteria were screened for its inhibitory effect against M. oryzae required contact-based interaction. In this study, Pseudomonas fluorescens strain TR3 was isolated from rice leaves infected by M. oryzae and identified by sequence analysis. When co-cultured on Complete Medium (CM) plates, strain TR3 caused fungal cell death in a contact-based manner. Separation by a dialysis tube with the cutoff molecular weight of 14 kDa eliminated the inhibitory or lysis effects of TR3 on M. oryzae, excluding the possible involvement of small antifungal metabolites. Treatment with TR3 affected the phosphorylation level of Pmk1 and reduced the rate of appressorium formation and virulence in M. oryzae. The type 3 secretion system (T3SS) was proven to play a role in bacterial and fungal interaction (BFI) using T3SS inducing medium (M9 medium). Disruption of hrcC, an essential T3SS gene of T3SS, blocked flagella development in TR3 and reduced growth inhibition activities to M. oryzae. These results indicate that strain TR3 may deliver effector proteins into fungal cells by T3SS and TR3-M. oryzae can be used for studying bacterial-fungal interactions at the molecular level.
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Rice blast forecasting models and their practical value: a review | KATSANTONIS | Phytopathologia Mediterranea

Rice blast forecasting models and their practical value: a review | KATSANTONIS | Phytopathologia Mediterranea | Rice Blast | Scoop.it
Rice, after wheat, is the second largest cereal crop, and is the most consumed major staple food for more people than any other crop. Rice blast (caused by Pyricularia oryzae, teleomorph Magnaporthe grisea) is the most destructive of all rice diseases, causing multi-million dollar losses every year. Chemical control of this disease remains the most effective rice blast management method. Many attempts have been made to develop models to forecast rice blast. A review of literature of the rice blast forecasting models revealed that 52 studies have been published, with the majority capable of predicting only leaf blast. The most frequent input variable has been air temperature, followed by relative humidity and rainfall. Critical factors for the pathogenesis, such as leaf wetness, nitrogen fertilization and variety resistance have had limited integration in the development of these models. This review reveals low rates of model application due to inaccuracies and uncertainties in the predictions. Five models are part of current operational forecasting systems in Japan, Korea and India. Development of in-field rice-specific weather stations, along with integration of leaf wetness and end-user interactive inputs should be considered. This review will be useful for modelers, users and stakeholders, to assist model development and selection of the most suitable models for the effective rice blast forecasting.
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FPD: A comprehensive phosphorylation database in fungi - ScienceDirect

FPD: A comprehensive phosphorylation database in fungi - ScienceDirect | Rice Blast | Scoop.it
Abstract

Protein phosphorylation, one of the most classic post-translational modification, plays a critical role in diverse cellular processes including cell cycle, growth, and signal transduction pathways. However, the available information about phosphorylation in fungi is limited. Here, we provided a Fungi Phosphorylation Database (FPD) that comprises high-confidence in vivo phosphosites identified by MS-based proteomics in various fungal species. This comprehensive phosphorylation database contains 62 272 non-redundant phosphorylation sites in 11 222 proteins across eight organisms, including Aspergillus flavus, Aspergillus nidulans, Fusarium graminearum, Magnaporthe oryzae, Neurospora crassa, Saccharomyces cerevisiae, Schizosaccharomyces pombe, and Cryptococcus neoformans. A fungi-specific phosphothreonine motif and several conserved phosphorylation motifs were discovered by comparatively analysing the pattern of phosphorylation sites in plants, animals, and fungi.
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