991 resultados para (cyst of P. conicum)


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Phoma leaf spot, caused by Phoma costarricensis poses a serious threat to coffee (Coffea arabica) production, especially in the highlands of the state of Minas Gerais, Brazil. Extracts of citric biomass, coffee berry husks and coffee leaves severely affected by rust caused by Hemileia vastatrix, were evaluated against P. costarricensis. In an in vitro assay, aqueous extracts of rusted leaves and berry husks plus the commercial extracts based on citric biomass named Ecolife® and Agromil® were tested at various dilutions on the mycelial growth inhibition of P. costarricensis. In vivo, coffee seedlings maintained in glasshouse, were sprayed with these extracts seven days before inoculation of P. costarricensis. Only extracts from citric biomass had inhibitory effects on the fungus. In vivo, Ecolife® (5 ml/l), Agromil® (5 g/l) and the aqueous extract of rusted coffee leaves (dilution 1:6) reduced Phoma leaf spot. Both, Ecolife® and the extract of rusted coffee leaves were significantly more effective in reducing the area under the lesion progress curve when applied at lower doses, indicating a possible effect on the induction of resistance.

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The virulence pattern of the isolates of Pyricularia grisea from commercial fields of the upland rice (Oryza sativa) cultivars 'Primavera' and 'BRS Bonança' was analyzed. A hundred and seventy monoconidial isolates of the pathogen virulent to 'Primavera' and 139 to 'BRS Bonança' collected from eight fields, during two years (2001-2003) were tested, under greenhouse conditions, on six newly released rice cultivars. Differences in virulence pattern were observed in pathogenic populations of 'Primavera' and 'BRS Bonança'. Isolates with virulence to improved cultivars were common in samples from farmers' fields in the absence of aloinfection. The virulence frequency of P. grisea isolates collected from 'Primavera'' to cultivars 'BRS Vencedora', 'BRS Colosso', 'BRS Liderança', 'BRS Soberana', 'BRS Curinga' and 'BRS Talento', was high in descending order. On the other hand, in the fungus population of 'BRS BRS Bonança' virulence frequency was high in 'BRS Talento', followed by 'BRS Curinga', 'BRS Vencedora', 'BRS Liderança', 'BRS Colosso' and 'BRS Soberana'. While virulence to 'BRS Talento' was rare among isolates from 'Primavera', it was most frequent in isolates of 'BRS Bonança'. The six improved rice cultivars permitted to differentiating agriculturally important virulences in the pathogen population which can be utilized in selecting breeding lines for specific resistance, in rice blast improvement program.

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A technique to measure the concentration of Penicillium allii conidia in damp chamber experiments by spectrophotometry was developed. A negative linear correlation (R²=0.56) was observed between transmittance at 340 nm and the concentration of P. allii conidia in water agar 0.05%. The equation that relates transmittance (T) with concentration (conidia mL-1) (y) is: y = 9.3 10(6) - 86497 T. The method was assayed by inoculating 43 P. allii strains in two garlic cultivars. The method proved to be more rapid than the traditional use of a hemocytometer with an improved accuracy. The CV of the number of conidia per hemocytometer reticule was of 35.04%, while the transmittance CV was of 2.73%. The extreme values chosen for T were 40 and 80 because the sensitivity of the method decreased when concentrations of conidia were out of this range.

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The phenotypic and genetic diversity of 77 isolates of Pyricularia grisea collected from two upland rice cultivars, Maravilha and Primavera, was studied. Isolates exhibiting compatible reaction to cv.Primavera were incompatible to cv.Maravilha and vice versa, with the exception of six isolates that were compatible to both cultivars. The virulence of isolates from cv. Maravilha on 32 test genotypes of rice was significantly higher (t = 9.09, p < 0.0001) than the isolates from cv.Primavera. A phenogram constructed from virulence data showed two main groups, one constituted mainly of isolates from cv.Primavera (97.6%) and the other of isolates from cv.Maravilha (91.17%). Rep-PCR analysis of isolates using two primers designed from sequences of Pot2 showed that isolates could be clustered broadly into two groups. The average similarity within a cluster of isolates from cv.Primavera was significantly greater than the average similarity among the isolates of cv.Maravilha (t = 5.37, p < 0.0001). There was close correspondence between clusters based on PCR and virulence data (r = 0.48, p < 0.011). The results showed that isolates of P. grisea were cultivar specific and had low phenotypic and genetic diversity.

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Meloidogyne mayaguensis has been reported in some states of Brazil causing severe damage on commercial guava (Psidium guajava L.). Accessions of Psidium spp. were selected from a collection maintained in Embrapa Clima Temperado (Pelotas, Rio Grande do Sul State). Plants of different accessions were grown from seed in plastic bags and, when they reached 15-20 cm in height, were inoculated with 10,000 eggs/plant of M. mayaguensis. Eight months after inoculation, the different accessions were evaluated for resistance to M. mayaguensis. Three accessions of P. guajava were highly susceptible (RF=59.2) to this nematode. Psidium friedrichsthalianium was considered to be moderately resistant (RF=1.9). Three accessions of P. cattleyanum were immune to M. mayaguensis (RF = 0). When used as rootstocks P. cattleyanum and P. friedrichsthalianium were compatible with P. guajava cv. Paluma. Considering these results, the use of resistant rootstocks provides a promising control method for M. mayaguensis in commercial guava crop.

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The electrochemical reduction of p-nitrobenzenesulfonyl chloride (NBSCl) in dimethylsulfoxide (DMSO) solution is used here as a model to investigate the role of sulfinic acid derivative in this compound's global reduction process. Cyclic voltammetric experiments reveal the production of sulfinic acid derivative, which is important in chemical reactions involving the original compound and other intermediates. This paper also discusses the probable mechanisms of the reduction.

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A simple analytical method for quantification of atenolol in pharmaceutical formulations by diffuse reflectance spectroscopy is described. The method is based on the reaction, on the filter paper surface, between the drug and p-chloranil producing a colored compound. The best reaction conditions were obtained with 20 µL of atenolol solution and 20 µL of p-chloranil. All reflectance measurements were carried out at 550 nm and the linear range was from 1.13x10-2 to 7.88x10-2 mol L-1 (r = 0.9992). The limit of detection was 2.80 x 10-3 mol L-1. The proposed method was successfully applied to analysis of different commercial brands of pharmaceutical formulations and the results obtained by the proposed method were in good agreement with those obtained using the British Pharmacopoeia method.

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Wheat (Triticum aestivum L.) blast caused by Pyricularia grisea is a new disease in Brazil and no resistant cultivars are available. The interactions between temperature and wetness durations have been used in many early warning systems. Hence, growth chamber experiments to assess the effect of different temperatures (10, 15, 20, 25, 30 and 35ºC) and the duration of spike-wetness (0, 5, 10, 15, 20, 25, 30, 35 and 40 hours) on the intensity of blast in cultivar BR23 were carried out. Each temperature formed an experiment and the duration of wetness the treatments. The highest blast intensity was observed at 30°C and increased as the duration of the wetting period increased while the lowest occurred at 25°C and 10 hours of spike wetness. Regardless of the temperature, no symptoms occurred when the wetting period was less than 10 hours but at 25°C and a 40 h wetting period blast intensity exceeded 85%. These variations in blast intensity as a function of temperature are explained by a generalized beta model and as a function of the duration of spike wetness by the Gompertz model. Disease intensity was modeled as a function of both temperature and the durations of spike wetness and the resulting equation provided a precise description of the response of P. grisea to temperatures and the durations of spike wetness. This model was used to construct tables that can be used to predict the intensity of P. grisea wheat blast based on the temperatures and the durations of wheat spike wetness obtained in the field.

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Studies on the genetic variability of Puccinia triticina in inoculum collected in Brazil started in 1941 with Vallega (20). The pioneering work in Brazil dates from 1949 (16) at "Instituto Agronômico do Sul", Ministry of Agriculture (MA), in Pelotas, Rio Grande do Sul State (RS), and continued after 1975 at Embrapa Wheat in Passo Fundo, RS. In 2002, analyses for the identification of P. triticina races continued at OR Seed breeding, simultaneously to Embrapa's program, both in Passo Fundo. The investigators involved in the identification of races in Brazil were Ady Raul da Silva in Pelotas (MA), Eliza Coelho in Pelotas (MA) and in Passo Fundo (Embrapa), Amarilis Labes Barcellos in Pelotas (MA) and in Passo Fundo (Embrapa and OR), Camila Turra in Passo Fundo (OR) and Marcia Chaves in Passo Fundo (Embrapa). From 1979 to 2010 growing season, 59 races were determined, according to the differentiation based on the expression of each Lr resistance gene. On average, one to three new races are detected per year. Research has focused on the use of vertical resistance; however, lately some institutes have searched more durable resistance, of the adult-plant type (horizontal, less race-specific). The uninterrupted monitoring of the wheat rust pathogenic population in Brazil during so many decades allowed the understanding of the evolution and virulence of races. The use of international nomenclature adopted by some programs has allowed the comparison of the fungus variability in Brazil with that in other countries, especially where frontiers are not barriers for spore transportation, confirmed by the occurrence of the same races all over one region.

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ABSTRACT The essay objective was to correlate lignin content resulting from tigmomorphogenesis induced by stem swaying with survival and post-planting growth of P. taeda seedlings. Seedlings were subjected to daily frequencies (0, 5, 10, 20 and 40 movements) of stem swaying for 60 days. By the end of the treatments, we determined lignin content of below and aboveground seedling tissues. Four replicates per treatment were planted in a area cultivated with pines. Ninety days after planting, survival and increments of seedling height, stem diameter and stem volume were quantified. Application of 20 stem swayings increased lignin in both below and aboveground plant tissues. Outplanted seedling survival was reduced with 40 stem swayings while growth increments were increased with both 10 and 20 stem swayings. Lignin content from belowground plant tissues was positively correlated with outplanted seedling survival while lignin from aboveground tissues correlated with height and stem volume increments. P. taeda seedlings with higher lignin content have higher survival chances after planting.

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ABSTRACT The present study aimed to evaluate the growth and the levels of N, P, K, Ca and Mg in Australian cedar seedlings which had been inoculated with arbuscular mycorrhizal fungi (AMF) in different types of containers. The experiment was carried out in a greenhouse and the experimental design was that of randomized complete blocks (RCB), with a 4 x 4 factorial design consisting of four inoculation treatments with AMF (Rhizophagus clarum, Gigaspora margarita, a mixed inoculation (R. clarum + G. margarita) and the control (with no AMF inoculation); four types of containers (plastic bags measuring 250 cm3, tubes of 55 and 130 cm3 and pressed blocks 440 cm3. plant-1), with four repetitions. The height, the diameter of the stem base, the aerial part dry weight (APDW), the dry weight of the root (DWR) and the total plant dry weight (DW) were measured, along with the Dickson quality index, the percentage of mycorrhizal colonization and the levels of N, P, K, Ca and Mg in the aerial part dry weight. One hundred and thirty eight days (138) days after sowing, the greatest growth and/or the highest levels of P, K and Ca could be observed in the aerial part dry weight of the Australian cedar seedlings which had been planted in the pressed block container and inoculated with a mixture of the two AMF species (G. margarita + R. clarum) or with just R. clarum. Thus it can be seen that AMF can make a significant contribution to the production of Australian cedar seedlings.

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The study aimed to evaluate chemical, microbiological and hydro-physical changes of a Dystrophic Yellow Latosol, receiver of different levels of manipueira (cassava wastewater) application, in the cultivation of 'Terra Maranhão' banana. The experimental design was a randomized block with three replications in a factorial scheme 3 x 4, in which it was considered three soil depths and four levels of manipueira. It was evaluated the weighted mean diameter of the aggregate, the percentage of aggregation at different periods, soil density, particle density, porosity and soil saturated hydraulic conductivity, in addition to pH of P (mg dm -3), K (mg dm-3), Ca (cmolc dm-3), Mg (cmolc dm-3), Ca+Mg (cmolc dm-3), Al (cmolc dm-3), Na (cmolc dm -3), H+Al (cmolc dm-3), CEC (cmolc dm-3), V%, OM (g kg-1), soil microbial biomass (Ug Cg-1 dry soil), acid phosphatase (Ug PNP g-1 h-1). The use of manipueira influenced some physical characteristic of the soil, but it was not possible to specify the effect of increasing application dosage. Therefore, the application did not affect the biological indicators assessed in the soil or its pH. The use of manipueira as a fertilizer in the doses used in this study showed low increase of K, P, H+Al and Al in the soil and a good increase of Mg, Ca and Ca+Mg, Na, CEC and V%.

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The goal of this study was to evaluate the nitrogen fertilization as deep litter for pigs in order to produce biomass and accumulate nutrients by the corn. A deep litter made of rice husk as organic compound, from a commercial pig farm during finishing phase, was used. After three consecutive batches of pigs, the deep litter was subjected to a maturation period of 50 days, and samples of this material were taken for analysis of agronomic value. The experimental design was completely randomized with five replicates. The treatments consisted of doses of 0, 75, 150 and 300mg dm-3 of N of deep litter, as well as an additional treatment with ammonium sulfate, with a dosage of 150mg dm-3 of N. After 45 days, corn plants were harvested in order to evaluate the total dry weight and nutrient concentrations of their aerial parts. Dry matter increases were found with more application of deep litter. Regarding control fertilization, the use of increasing dosages of deep litter allowed accumulation of K, reduced the availability of P, Ca, Mg, Zn and B and did not alter the concentrations of N, Cu, Fe and Mn.

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OBJECTIVE: To analyze the lesions diagnosed in victims of falls, comparing them with those diagnosed in other mechanisms of blunt trauma.METHODS: We conducted a retrospective study of trauma protocol charts (prospectively collected) from 2008 to 2010, including victims of trauma over 13 years of age admitted to the emergency room. The severity of injuries was stratified by the Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS). Variables were compared between the group of victims of falls from height (Group 1) and the other victims of blunt trauma (Group 2). We used the Student t, chi-square and Fisher tests for comparison between groups, considering the value of p <0.05 as significant.RESULTS: The series comprised 4,532 cases of blunt trauma, of which 555 (12.2%) were victims of falls from height. Severe lesions (AISe"3) were observed in the extremities (17.5%), in the cephalic segment (8.4%), chest (5.5%) and the abdomen (2.9%). Victims of Group 1 had significantly higher mean age, AIS in extremities / pelvis, AIS in the thoracic segment and ISS (p <0.05). The group 1 had significantly (p <0.05) higher incidence of tracheal intubation on admission, pneumothorax, hemothorax, rib fractures, chest drainage, spinal trauma, pelvic fractures, complex pelvic fractures and fractures to the upper limbs.CONCLUSION: Victims of fall from height had greater anatomic injury severity, greater frequency and severity of lesions in the thoracic segment and extremities.

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Objective: To evaluate the perioperative use of atenolol in reducing the incidence of hematoma after rhytidoplasty.Methods: Between January 2007 and February 2013, 80 patients were randomized into two groups: Group A (n = 26) received perioperative atenolol in order to maintain heart rate (PR) around 60 per minute; Group B (n = 54) did not receive atenolol. Both groups underwent the same anesthetic and surgical technique. We monitored blood pressure (BP), HR, hematoma formation and the need for drainage. Patients were followed-up until the 90th postoperative day. The variables were compared between the groups using the ANOVA test. Continuous variables were presented as mean ± standard deviation and the differences were compared with the Student's t test. Values of p d" 0.05 were considered significant.Results: In group A the mean BP (110-70mmHg ± 7.07) and HR (64 / min ± 5) were lower (p d" 0.05) than in group B (135-90mmHg ± 10.6) and (76 / min ± 7.5), respectively. There were four cases of expansive hematoma in group B, all requiring reoperation for drainage, and none in group A (p d" 0,001).Conclusion: The perioperative use of atenolol caused a decrease in blood pressure and heart rate and decreased the incidence of expanding hematoma after rhytidectomy.