RESUMEN
Twenty-two Colletotrichum strains were isolated from anthracnose symptoms or leaf spots on leaves of various wild Poaceae and Cyperaceae plants collected in three provinces of Iran and tentatively identified as belonging to the Graminicola species complex based on morphology. All strains were studied via a polyphasic approach combining colony characteristics, morphology and phylogeny inferred from multi-locus sequences, including the nuc rDNA ITS1-5.8S-ITS2 (ITS), partial sequences of the ß-tubulin (tub2), actin (act), manganese superoxide dismutase 2 (sod2), DNA lyase 2 (apn2) genes, a 200-bp intron of the glyceraldehyde-3-phosphate dehydrogenase (gapdh), and the intergenic spacer between the apn2 gene and the mat1 idiomorph (apn2/mat1). Six species were distinguished, including three new species, namely C. caspicum, C. persicum, and C. sacchari, and three previously described species, C. cereale, C. nicholsonii and C. sublineola. Comprehensive morphological descriptions and illustrations are provided for all species. Furthermore, this study provided new insights into the distribution and host range of known species.
Asunto(s)
Colletotrichum , Cyperaceae , Irán , Enfermedades de las Plantas , PoaceaeRESUMEN
OBJECTIVES: Several popular cardiovascular risk assessment tools have been developed in Western countries; however, the predictive abilities of these tools have not been evaluated in Middle Eastern countries. The present study aimed to determine the abilities of cardiovascular risk assessment tools in a population-based study in Northern Iran. STUDY DESIGN: Population-based cohort study in Northern Iran. METHODS: In total, 2883 individuals (1629 men and 1254 women), aged 40-74 years, were included in the study. We determined the predictive abilities of the American College of Cardiology/American Heart Association (ACC/AHA) risk prediction tool, the Framingham general cardiovascular risk proï¬le in primary care settings, and the Systematic Coronary Risk Evaluation (SCORE) equations for low- and high-risk European countries. Receiver operating characteristic (ROC) analysis was used to determine the predictive abilities of these four risk assessment tools. RESULTS: Based on areas under curve (AUC) values and related 95% confidence intervals (95% CIs), the discriminative abilities of the ACC/AHA tool, the Framingham approach, and the SCORE for low- and high-risk European countries to estimate non-fatal cardiovascular disease (CVD) events were 0.6625, 0.6517, 0.6476 and 0.6458, respectively, in men, and 0.7722, 0.7525, 0.7330 and 0.7331, respectively, in women. Moreover, the abilities of these four tools to estimate fatal CVD events were found to be 0.8614, 0.8329, 0.7996 and 0.7988 in men, and 0.8779, 0.8372, 0.8535 and 0.8518 in women, respectively. CONCLUSIONS: The cardiovascular risk assessment tools investigated in this study showed acceptable predictive abilities in women. The ACC/AHA approach showed slightly better performance compared with the SCORE tool; however, the SCORE tool benefited from the lowest cost compared with all the other tools.
Asunto(s)
Enfermedades Cardiovasculares , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Europa (Continente) , Femenino , Humanos , Irán/epidemiología , Masculino , Medición de Riesgo , Factores de Riesgo , Estados UnidosRESUMEN
Mucormycosis is a rare but fulminant opportunistic fungal infection, which occurs most often in diabetic and immunocompromised patients. Dental extractions may create a portal of entry for the fungal infection. The mucormycosis may be the original cause of the pain and can be misdiagnosed as dental pain. In this paper, two cases of mucormycosis are reported after dental extractions and successfully treated with amphotericin B (case #1) and combined with posaconazole (case #2). The two cases we describe exemplify the fulminant mucormycosis of maxillary sinuses after dental extraction inpatients with uncontrolled diabetic support the findings that this predisposing condition created a suitable environment for the Mucorales growth. These case reports emphasize early recognition and urgent treatment of mucormycosis is necessary to prevent the spread of infection Therefore, dental surgeons and healthcare practitioners should become familiar with mucormycosis.
Asunto(s)
Seno Maxilar/microbiología , Mucorales/aislamiento & purificación , Mucormicosis/diagnóstico , Sinusitis/diagnóstico , Extracción Dental/efectos adversos , Adulto , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Complicaciones de la Diabetes/microbiología , Diabetes Mellitus/microbiología , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Mucorales/efectos de los fármacos , Mucormicosis/etiología , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Sinusitis/microbiología , Resultado del Tratamiento , Triazoles/uso terapéuticoRESUMEN
Metastatic cancer is regarded as one of the largest contributors to disease-related deaths worldwide. Poor patient prognosis and treatment outcome is tied to the lack of efficacious anti-cancer therapies, which is due in part to the lack of physiologically relevant in vitro screening systems that can mimic the native tumor microenvironment. Conventional drug-screening platforms, which are often used in the pharmaceutical industry, are either two-dimensional (2D) assays or three-dimensional (3D) hydrogel-based matrices that lack precise control over cell distribution, matrix architecture, and organization. Despite the significance of in vivo models, they have limitations as it is difficult to control and analyze the influence of specific variables within their tumor microenvironment. Thus, there is still a crucial need to develop tumor models that enable precise control of microenvironmental cues (e.g. matrix composition, soluble factors, cellular organization) to assess the efficacy of anti-cancer drugs. Herein, we report the development and validation of a 3D microfluidic invasion platform for anti-cancer drug studies. Our platform allowed for compartmentalization of tumor and stromal fibroblasts in a defined architecture, thereby enabling pharmacokinetic drug transport to a cell-dense tumor region. We analyzed the effect of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor, on the behavior of SUM159 breast cancer cells. Many HDAC inhibitors, including SAHA, have been a subject of controversy with highly conflicting results for the treatment of solid tumors in vitro as well as in clinical trials. We found that SAHA significantly inhibited cellular migration/proliferation, and decreased microtubule polarization.
Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Ácidos Hidroxámicos/farmacología , Microfluídica , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Difusión , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Microtúbulos/patología , Invasividad Neoplásica , Metástasis de la Neoplasia , VorinostatRESUMEN
The main aim of present study was to prepare chitosan (CS) and chitosan nanoparticles (CS/NPs) to evaluate their antifungal and oxidative activity. CS/NPs were prepared based on the ionic gelation of CS with tripolyphosphate (TPP) anions by using centrifugation and pH change. The obtained nanoparticles (NPs) were characterized by size and zeta potential analysis. The antifungal activity of the CS and CS/NPs were evaluated on the Fusarium graminearum, which causes Fusarium head blight (FHB) on wheat by the method of spraying on the Potato dextrose agar (PDA) medium. The Dynamic light scattering (DLS) indicated that particle diameter (z-average) was approximately 180.9±35.5-339.4±50.9 and 225.7±42.81-595.7±81.7nm for NPs prepared from CS with different molecular weights by using centrifugation and pH change methods, respectively. Different concentrations of CS and NPs were tested to know the inhibitory effect of F. graminearum. Low molecular weight (LMW) CS and its NPs had high potential of antifungal activity on suppress of fungus growth. The maximum percentage of growth reduction was 68.18%, and 77.5% by CS and its NPs at concentrations of 1000 and 5000ppm, respectively. In greenhouse trials, at 28days after inoculation (dpi), the area under the disease progress curve (AUDPC) from 7 dpi to 28 dpi of control plants treated with acetic acid aqueous solution and distilled water was almost up to 7.36 and 7.7, respectively, while plants treated with CS and NPs only had approximately 3.61 and 3.34, respectively. Results revealed that H2O2 accumulations displayed a different pattern during the activation of plant defense systems, it had brownish sites on the infected palea. Since 24h post inoculation (hpi), the H2O2 accumulations were shown in both CS and NPs, and the elevated H2O2 accumulation appeared in 72 hpi in both treatments. CS and NPs at high concentration increased the degree of tissue and cell injury. The obtained results clearly suggest that CS and its NPs have remarkable potential for further field screening towards crop protection.
Asunto(s)
Quitosano/química , Quitosano/farmacología , Fusarium/efectos de los fármacos , Fusarium/fisiología , Nanopartículas , Triticum/metabolismo , Triticum/microbiología , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Quitosano/síntesis química , Peróxido de Hidrógeno/metabolismo , Peso Molecular , Oxidación-Reducción , Tamaño de la Partícula , Enfermedades de las Plantas/microbiología , Superóxidos/metabolismo , Propiedades de Superficie , Triticum/efectos de los fármacosRESUMEN
Fusarium head blight (FHB) disease caused by Fusarium graminearum is one of the most important diseases of wheat in humid and warm areas. This disease significantly reduces yield as well as seed quality. The aim of this work was to evaluate the possibility of control of FHB by chitosan (CS) and chitosan nanoparticles (CS/NPs). In vitro, the application of various concentrations of CS and CS/NPs showed significant inhibition of both radial mycelial growth and number of colonies formed against F. graminearum. The application of 1000 and 5000ppm concentration of CS and CS/NPs produced maximum inhibition of radial mycelial growth in comparison to the control, respectively. The microscopic examination, of treated F. graminearum with the CS and CS/NPs, showed dehydration and deformation in mycelial growth and some hyphae were collapsed. The maximum percentage reduction number of colonies was observed in 5000ppm concentration of both CS and CS/NPs. To test the effect of CS and CS/NPs on spore germination, four concentrations were used for 4 and 24h incubation. The 24h incubation of F. graminearum spores with a 5000ppm solution of CS greatly reduced the number of germinating spores. In greenhouse trials, the disease severity percentage was low when CS and CS/NPs were applied before fungus inoculation on the plants and 1000ppm concentration. The spores of F. graminearum germinated on the anther, hyphae penetrated into anther and colonized the palea, lemma and glume after 24 and 72 hpi, respectively. Wherease, the spikelets treated with CS and CS/NPs were infected slowly. Light microscopy and TEM observations indicated that mycelium penetrated into the cells through stoma and transited to other cells by cell wall or plasmodesmata. Mycelial growth caused conidia into cells but CS and CS/NPs prevented of it's growth. Results showed that CS and CS/NPs could be a useful biological pesticide for controlling FHB.
Asunto(s)
Quitosano/química , Quitosano/farmacología , Ambiente Controlado , Fusarium/efectos de los fármacos , Fusarium/fisiología , Nanopartículas , Triticum/microbiología , Relación Dosis-Respuesta a Droga , Fusarium/crecimiento & desarrollo , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Tamaño de la Partícula , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/fisiologíaRESUMEN
We have recently reported a genome-scale catalog of human protein-coding genes that contain "exceptionally long" STRs (≥6-repeats) in their core promoter, which may be of selective advantage in this species. At the top of that list, SCGB2B2 (also known as SCGBL), contains one of the longest CA-repeat STRs identified in a human gene core promoter, at 25-repeats. In the study reported here, we analyzed the conservation status of this CA-STR across evolution. The functional implication of this STR to alter gene expression activity was also analyzed in the HEK-293 cell line. We report that the SCGB2B2 core promoter CA-repeat reaches exceptional lengths, ranging from 9- to 25-repeats, across Apes (Hominoids) and the Old World monkeys (CA>2-repeats were not detected in any other species). The longest CA-repeats and highest identity in the SCGB2B2 protein sequence were observed between human and bonobo. A trend for increased gene expression activity was observed from the shorter to the longer CA-repeats (p<0.009), and the CA-repeat increased gene expression activity, per se (p<0.02). We propose that the SCGB2B2 gene core promoter CA-repeat functions as an expression code for the evolution of Apes and the Old World monkeys.
Asunto(s)
Cercopithecidae/genética , Repeticiones de Dinucleótido , Evolución Molecular , Hominidae/genética , Regiones Promotoras Genéticas , Secretoglobinas/genética , Animales , HumanosRESUMEN
BACKGROUND AND PURPOSE: Rhino-orbito-cerebral mucormycosis (ROCM) is a rare disease with acute and fulminant manifestation. This infection is associated with high morbidity and mortality rates. Herein, we reviewed the manifestations, underlying conditions, medical treatments, and surgical interventions in ROCM patients admitted to a tertiary referral center in northern Iran over a seven-year period. MATERIALS AND METHODS: In a retrospective analysis, 15 cases of ROCM were identified from 2007 to 2013 in Bu Ali Sina Hospital, Sari, Iran. All the ROCM cases were clinically diagnosed and confirmed by histopathological and/or mycological examination. The relevant demographic data, clinical, ophthalmic, and neurologic manifestations, underlying conditions, medical treatments, and surgical interventions were recorded and analyzed. RESULTS: The mean age of the patients was 54±11 years (age range: 28-70 years); 26.7% of the patients were male and 73.3% female (male: female ratio of 1: 2.7). Uncontrolled diabetes was noted in at least 86.7% (13/15) of the cases. The maxillary sinuses were the most frequently involved sites (66.7% of the cases) followed by the ethmoid sinus. Amphotericin B in combination with surgical debridement was used in the treatment of 80% of the cases. Furthermore, 73.3% of the patients who were diagnosed early and underwent medical and extensive surgical debridement of the infected tissues survived. CONCLUSION: Uncontrolled diabetes mellitus is considered to be the main predisposing factor for ROCM. To prevent and reduce mortality rate of this acute disease, early diagnosis based on clinical findings and biopsy is recommended.
RESUMEN
In order to identify a specific marker for T. harzianum AS12-2, a strain capable of controlling rice sheath blight caused by Rhizoctonia solani, UP-PCR was performed using five universal primers (UP) both separately and in pairwise combinations. The application of two UP primers resulted in the amplification of unique fragments from the genomic DNA of T. harzianum AS12-2, clearly distinguishing it from other Trichoderma strains. The unique fragments had no significant sequence homology with any other known sequence available in databases. Based on the sequences of the unique fragments, 14 oligonucleotide primers were designed. Two primer sets amplified a fragment of expected size from the DNA of strain T. harzianum AS12-2 but not from any other examined strains belonging to T. harzianum, to other Trichoderma species assayed, or to other common fungi present in paddy fields of Mazandaran province, Iran. In conclusion, SCAR (sequence characterized amplified regions) markers were successfully identified and rapid, reliable tools were provided for the detection of an effective biocontrol Trichoderma strain, which can facilitate studies of its population dynamics and establishment after release into the natural environment.
Asunto(s)
ADN de Plantas/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Oryza/microbiología , Control Biológico de Vectores/métodos , Enfermedades de las Plantas/prevención & control , Rhizoctonia/patogenicidad , Trichoderma/genética , Dermatoglifia del ADN , Marcadores Genéticos/genética , Irán , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
One hundred and eighteen isolates of Rhizoctonia solani were gathered from infected roots and hypocotyls of bean (Phaseolus vulgaris L.) grown in the fields of Tehran Province, Iran. Two isolates of the collected samples belonged to binucleate and 81 isolates to multinucleate of R. solani. The multinucleate isolates showed different anastomosis groups as AG-4 (subg. AG-4 HGI, AG-4HGII), AG-6 and AG-2. In greenhouse, pathogenicity tests carried out on bean cv. Naz in randomized design with 4 replications and each replication (pots) with 5 seeds of bean. Infection was done with seeds of wheat which were infected to the fungus with pasteurized soil. Results showed that the highest disease severity was caused by AG-4 (Rs21) isolates, whereas AG-4 (Rs74) isolates were weakly pathogenic with 90% and 21% infection, respectively. In this test the major pathogenic isolates belonged to AG-4 and they caused seed rot and damping-off of bean and AG-6 isolates were non-pathogenic. Five isolates of the fungus with major pathogenicity (Rs7, Rs18, Rs21, Rs62 and Rs71) selected and used for the reaction with different cultivars of bean. In this test, the cultivars and lines of bean (Pinto, red, white, green) studied in factorial experiment as randomized block design with 4 replications (pots). Results showed that none of the cultivars was completely resistant, however green bean cv. Sanry and pinto cv. Shad with number 4.8 disease severities had the highest susceptibility to seed rot and damping-off and red bean cv. Goli with 2.58 had the lowest susceptibility to the infection. Reaction of the cultivars and lines to the isolates of R. solani was significantly different at 1% level. Isolates of the fungus, Rs7, Rs21 with 84%, 90% pathogenicity was more virulent than the others.
Asunto(s)
Phaseolus/microbiología , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , Rhizoctonia/patogenicidad , Fungicidas Industriales/uso terapéutico , Tallos de la Planta/microbiología , Rhizoctonia/aislamiento & purificaciónRESUMEN
Bean is one of the major crops in Iran. Seed rot and damping-off caused by Rhizoctonia solani is the most important disease of bean. In this research, infected roots and seedlings of beans were collected from different fields of Tehran Province. The samples were sterilized with 10% sodium hypochloride (5% stock) and incubated on PDA surface in petri-dishes. The purified fungi kept on filter paper and identified, pathogenicity test of R. solani was carried out on 2 cultivars of bean (red bean cv. Naz and white bean cv. Dehghan) and it determined. For identification of the anastomosis groups, the discs of cultured media with 5 mm. diameter of standard AG placed on one side of microscopic slides covered with water agar (2%) of 1 mm. thick and the isolates of the fungus on another side of slide about 2 cm away from each other. Experiment carried out in 4 replications. The cultures were incubated in 25 +/- 1 degrees C incubator for 24 hours, then the mycelial contact stained with lactophenol, cotton blue and hyphal anastomosis looked for under the light microscope with 10 x 40 and 10 x 100 magnifications. As a result, anastomosis groups: AG4, AG4HGII, AG2-2-2B and AG6 determined, frequency of these groups were 64, 18, 2, 16%, respectively. The group AG6 and subgroups AG4HGII and AG2-2-2B are introduced as new anastomosis groups on bean in Iran.
Asunto(s)
Phaseolus/microbiología , Enfermedades de las Plantas/microbiología , Rhizoctonia , Recuento de Colonia Microbiana , Fabaceae/microbiología , Irán , Raíces de Plantas/microbiología , Rhizoctonia/aislamiento & purificación , Rhizoctonia/patogenicidad , Rhizoctonia/ultraestructuraRESUMEN
Fluorescent Pseudomonas species are an important group of PGPR that suppress fungal root and seedling disease by production of antifungal metabolites such as 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin, pyrolinitrin, siderophores and HCN. The compound 2,4-DAPG is a major determinant in biocontrol of plant pathogens. A 7.2 kbp chromosomal DNA region, carrying DAPG biosynthetic genes (phlA, phlC, phlB, phlD, phIE and phlF). Detecting the ph1 genes make them an ideal marker gene for 2,4-DAPG-producing fluorescent pseudomonad's. In this study we detected ph1A gene (that convert MAPG to 2,4-DAPG) using PCR assay with primers phlA-1r and phlA- f that enabled amplification of phlA sequences from fluorescent pseudomonad's from ARDRA group 1 and 3. We could detect phlA gene in P. fluorescens strains CHAO, Pf-44, Pf-1, Pf-2, Pf-3, Pf-17, Pf-62 and Pf-64, native isolates of Iran. The efficacy of this method for rapid assay characterizing rhizosphere population of 2,4-DAPG producing bacteria from soil of different area of Iran is in progress. We used a collection of 48 fluorescent pseudomonas strains in vitro, with known biological control activity against some soil born phytopathogenic fungi such as, Macrophomina phaseoli, Rhizoctonia solani Vericillium dahlia, Phytophthora nicotiana, Pythium spp. and Fusarium spp. and the potential to produce known secondary metabolites such as protease. Strains Pf-1, Pf-2, Pf-3, Pf-17, Pf-33 and Pf-44 showed the best antifungal activity against all fungi used in this study. Thirty-eight of 48 strains produced protease. The ability to rapidly characterize populations of 2,4-DAPG producers will greatly enhance our understanding of their role in the suppression of root disease.
Asunto(s)
ADN Bacteriano/análisis , Hongos/crecimiento & desarrollo , Control Biológico de Vectores/métodos , Enfermedades de las Plantas/microbiología , Pseudomonas fluorescens , Antibiosis , Amplificación de Genes , Pruebas de Sensibilidad Microbiana , Floroglucinol/análogos & derivados , Floroglucinol/aislamiento & purificación , Floroglucinol/farmacología , Raíces de Plantas/microbiología , Reacción en Cadena de la Polimerasa , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/metabolismo , Pseudomonas fluorescens/fisiologíaRESUMEN
The population structure of Magnaporthe grisea, the causal agent of the rice blast, was analyzed in Mazandaran province, using DNA fingerprinting based on RAPD-PCR by means of three primers including "I", "D" and "H". Total DNA of 47 isolates was extracted and amplified according to a specific PCR program. As a result, variable length fragments were generated. Each isolate was subjected to DNA fingerprinting and clonal lineages were determined. Phenetic analysis differentiated three distinct fingerprint lineages. In order to study on fertility status and distribution of the mating type idiomorphs (alleles), 72 monoconidial isolates from Mazandaran province were paired with four standard fertile hermaphrodite isolates. The mating type of 36 isolates was determined as Mat 1-1. The others (36 isolates) did not form any perithecia in pairing with standard isolates
Asunto(s)
ADN de Hongos/análisis , Variación Genética , Magnaporthe/genética , Magnaporthe/aislamiento & purificación , Oryza/microbiología , Dermatoglifia del ADN , Frecuencia de los Genes , Enfermedades de las Plantas/microbiología , Técnica del ADN Polimorfo Amplificado Aleatorio/métodosRESUMEN
Verticillium wilt caused by Verticillium dahliae is a serious problem of olive trees leading to significant reduction in yield. Verticillium wilt of olive trees was first recorded in Iran 1996 and confirm as due to Verticillium dahliae Kleb. 101 isolates of V. dahliae from olive trees at deferent locations in north provinces of Iran were assigned to vegetative compatibility groups (VCGS), using nitrate non-utilizing (Nit) mutants. A higher frequency of nit 1/nit 3 mutants (93%) was obtained compared with NitM (7%) with 10% of the isolates being assigned to VCG1 and 51% VCG4B and 19% VCG2A. 20% of isolates could not be classified in standard isolates. The pathogenecity of 15 randomly selected isolates (5 of each VCG) was tested on olive seedling (cv. Zard) and eggplant. The VCGs isolates were similarly aggressive on olive. However, VCG1 isolates were more aggressive on eggplant cv. Local than the VCG2A and VCG4B isolates as indicated by a higher colonization index. The pathogenecity tests of the pathogen on test plants (cotton cv. 'sahel', eggplant cv. 'local' and tomato cv. 'ps') show all isolates category in 2 pathogenecity groups defoliate and non-defoliate (with severe and mild subgroups). The morphology of V. dahliae isolates on C'zapeck's agar and water agar medium were different especially for microsclerotia appearance time in culture and their morphology.
Asunto(s)
Olea/microbiología , Enfermedades de las Plantas/microbiología , Verticillium/aislamiento & purificación , Verticillium/patogenicidad , Irán , Raíces de Plantas/microbiología , Solanum melongena/microbiología , Verticillium/genéticaRESUMEN
107 samples of E. betae were collected on infected leaves from all over Iranian beet cultivation areas. Their choosing were based on geographical and host origin(sugar beet, red beet, fodder beet and wild beet). 30 isolates were single colonized and grown on sugar beet susceptible genotype 7233. 107 specimens were analyzed by restriction fragment length polymorphism (RFLP) of the ribosomal internal transcribed spacers (ITS) and 5.8s DNA which previously amplified by the polymerase chain reaction (PCR) with 2 universal primers, ITS1 and ITS4. PCR product was affected by 9 different restriction enzymes. PCR product was a 645 bp band for all of the isolates. 3 restriction enzymes; CfoI, MspI and HaeIII could cut this fragment into smaller bands, but electrophoretic patterns were identical for all of the isolates. 30 single colonized isolates were used in RAPD experiments. In RAPD-PCR experiment genetic diversity was investigated with 30 isolates from different parts of the country. 59 random primers were used and then 21 primers that displayed good consistency and reproducibility were selected. Most of the primers revealed identical patterns between 3 to 14 bands. 5 primers that showed more polymorphism were selected to analyze 30 isolates. For these 5 primers 61 distinct bands were obtained which 62% of these bands were polymorphic. Results indicated that there is no relationship between cluster grouping and geographical origin and the isolates showed a high similarity.
Asunto(s)
Ascomicetos/genética , Beta vulgaris/microbiología , ADN de Hongos/análisis , Enfermedades de las Plantas/microbiología , Polimorfismo de Longitud del Fragmento de Restricción , Ascomicetos/patogenicidad , Secuencia de Bases , Análisis por Conglomerados , ADN Espaciador Ribosómico , Variación Genética , Genotipo , Irán , Filogenia , Hojas de la Planta/microbiología , Técnica del ADN Polimorfo Amplificado Aleatorio , Mapeo RestrictivoRESUMEN
During 2000--03, different areas in Zanjan, Golestan and Khorasan provinces were surveyed for the presence of olive dieback. Olive branches, leaves and roots showing typical symptoms and soil around the roots were collected for further study. Samples were surface-sterilized with sodium hypochlorite or ethanol and then cultured on PDA and Czapek media. Soil samples were diluted in ethanol-agar for fungal isolation and purification. Morphological characteristics of the fungal mycelium particularly phialide and spores identified the causal agent to be the soil-borne pathogen, Verticillium dahliae. The disease was present in all olive growing regions but it was severe in temperate and relatively humid regions such as Gorgan. Infection index of the disease varied between 5 to 30% with an average of 11.89+/-1.12 among various orchards in this area. The newly established orchards showed more infection than the older ones. A significant difference in disease incidence and severity were observed among olive cultivars of Michen, Roughani, Zard and Koronakei. The latter cultivar had the least amount of infection. Strains of V. dahliae isolated from olive trees had different morphological and pathogenicity characteristics. These strains had different growth rates in response to the optimum temperature of 20 or 25 degrees C. The number of fungal propagules per gram of air-dried soil ranged from 2 to 32 with an average number of 13.42+/-0.50. Regarding the number of propagules of V. dahliae in the soil and susceptibility of cultivars in the newly established orchards, it seems necessary to take serious control measures to prevent disease spread.
Asunto(s)
Olea/microbiología , Verticillium/patogenicidad , Irán , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Tallos de la Planta/microbiología , Microbiología del Suelo , Verticillium/aislamiento & purificaciónRESUMEN
Wheat is an economic and important crop that provides approximately 20% of food calorie in the world. It is first crop in Iran and cultivated in the most areas of this country. Store-pit fungi make undesirable changes in quality and appearance of wheat grains. Even, some fungi produce different mycotoxins which are toxic to human and livestock's that use wheat grains as source of food. In this study, several samples were randomly collected from each of five store-pits located in different areas of Markazi Province including: Arak, Mahallat, Khomein, Saveh and Sarband. Grains were treated on PDA, and blotter, agar and washing test also used for isolating and detection of fungi. At least 100 grains per each sample were randomly used for each test and treatment. The fungi that determined in this study were Cochliobolus australiensis, Cladosporium herbarum, Epicoccum sp., Tilletia leavis, Aspergillus flavus, A. niger, A. fumigatus, Alternaria alternata, Alternaria sp., Penicillium italicum, P. digitatum, Fusarium sp., Rhizopus sp., Ustilago tritici, Scytalidium sp. Among these fungi the most isolates were belonged to Cladosporium, Alternaria, Rhizopus and Fusarium. Cladosporium herbarum was the most common in different sampling areas. Tilletia laevis and Ustilago tritici were just recovered in washing test. This study revealed that different fungi are associated with wheat grains in store-pits in Markazi Province. Some of them like Aspergillus flavus normally produce aflatoxin, a very toxic and carcinogenic mycotoxin that is harmful for human.
Asunto(s)
Conservación de Alimentos , Hongos/aislamiento & purificación , Micosis/clasificación , Enfermedades de las Plantas/microbiología , Triticum/microbiología , Animales , Aspergillus/aislamiento & purificación , Hongos/clasificación , Humanos , Irán , Micotoxinas/toxicidad , Penicillium/aislamiento & purificaciónRESUMEN
Blast, caused by Magnaporthe grisea, is one of the most important diseases in rice production regions of the world including Iran. To determine progress of rice blast disease on the selective cultivars and lines also to assay some components of partial resistance, a set of Iranian rice cultivars (Local and breeding) along with near-isogenic lines (NILs) and breeding lines from International Rice Research Institute (IRRI) were tested with some field races of the fungus in blast nursery and five of selective races in greenhouse. These experiments were conducted in a Randomized complete Block Design (RCBD) with three replications (except greenhouse experiment on the leaves). Traits in this study consisted of Infection Neck Number (INN), Neck Lesion Size (NLS), Infection Type (IT), percent Diseased Leaf Area (DLA) and Area Under Disease Progress Curve (AUDPC); also IT, Sporulation Lesion Number (SLN), Sporulating Region Diameter (SRD) and percent DLA were measured in leaf blast in greenhouse (one replication). The Iranian local cultivars and NILs i.e. Co-39 and C104-PKT located as susceptible group for AUDPC, IT, INN and NLS. Iranian breeding cultivars, breeding lines from IRRI and NILs (except Co-39 and C104-PKT) were resistant or indicated hypersensivity reaction (HR). Some cultivars (Fujiminori, Onda, and Hassan Saraii) were semi susceptible to leaf blast in nursery. The main point is correlation in 1% (a = 0.0001) between the traits in greenhouse and blast nursery. Neck node infection of Haraz cultivar in greenhouse experiment to IA-89 race is very important, because Haraz is a resistant cultivar to blast disease in Iran.