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The Ralstonia solanacearum species complex (RSSC) can cause bacterial wilt in a wide variety of plant species, including a number of ornamental glasshouse crops. Recently in Europe, ornamental rose plants for the production of cut flowers and propagation materials have been strongly affected by Ralstonia pseudosolanacearum, phylotype I, biovar 3. To test for the presence of the pathogen in the glasshouse, sampling of water from a drainage gutter or well may be an efficient strategy since it is known that RSSC can be released from infected root systems in the water. A protocol was developed to detect low densities of R. pseudosolanacearum in drain water collected from rose growers. Drain water was filtered through a bacterial filter, the filtrate was collected and target bacteria enriched for 48 h in Semi‐selective Medium South Africa (SMSA) broth supplemented with sterilized tomato plant extracts. DNA extracted from the enrichment broth was analysed using a TaqMan test in a duplex format, based on specific egl sequences of RSSC and the use of an extraction and amplification control. The optimized protocol had a detection level of ≤1–10 colony forming units of R. pseudosolanacearum in drain water. [ABSTRACT FROM AUTHOR]

The continuous wavelet transform is a powerful tool for multiscale data analysis. It has wide applications in physics, mathematics, natural sciences and even great appeal in engineering, computing and areas of technology and innovation. As an introductory point of view, the wavelet transform has been widely addressed in previous works. Thus, this presentation emphasizes the use of this technique in theoretical and practical situations that are not usually explored, but situations that are fundamental to a better use, or even a correct use, of this tool. Consistent bases enable mainly extensions of wavelet application to new investigations, that are facilitated by the availability of free programs and tools, and even several of these in completely available distribution of resources (free softwares). The content of this article, by the authors' choice criteria, presents concepts and examples of techniques that can be of great interest for various studies in physics and other related areas. This text is aimed at researchers, teachers and graduate students, with the possibility of still meet the preparation needs of students at last undergraduation stage. [ABSTRACT FROM AUTHOR]

A potential cause of the dissemination of the potato ring rot bacterium Clavibacter sepedonicus (Cs) is the use of automated seed potato cutters. The present study focuses on the question of whether disinfection practices are sufficient to prevent the transmission of Cs from contaminated machine parts to a new tuber lot. The disinfection efficacy was determined by establishing the culturability of Cs that remained after spray application of sodium-p-toluenesulfochloramide solution on clean and fouled specimens of machinery material that had been provided with an imprint of Cs biofilm. Although conventional spraying, with the authorized concentration of sodium-p-toluenesulfochloramide, of inoculated rubber, PVC and lacquered steel led to a substantial decrease of colony forming units, the treatment was insufficient for complete eradication of Cs. The presence of dirt negatively affected the efficacy of the disinfectant. [ABSTRACT FROM AUTHOR]

The socio‐economic impact of Fusarium odoratissimum, which is colloquially called tropical race 4 (TR4), is escalating as this fungal pathogen spreads to new banana‐growing areas. Hence, the development of simple, reliable and rapid detection technologies is indispensable for implementing quarantine measures. Here, a versatile loop‐mediated isothermal amplification (LAMP) assay has been developed that is applicable under field and laboratory conditions. DNA markers unique to TR4 isolates were obtained by diversity arrays technology sequencing (DArTseq), a genotyping by sequencing technology that was conducted on 27 genotypes, comprising 24 previously reported vegetative compatibility groups (VCGs) and three TR4 isolates. The developed LAMP TR4 assay was successfully tested using 22 TR4 isolates and 45 non‐target fungal and bacterial isolates, as well as on infected plants under greenhouse and field conditions. The detection limit was 1 pg µL−1 pure TR4 DNA or 102 copies plasmid‐localized TR4 unique sequence (SeqA) per reaction, which was not affected by background DNA in complex samples. The LAMP TR4 assay offers a powerful tool for the routine and unambiguous identification of banana plants infected with TR4, contributing to advanced diagnosis in field situations and monitoring of fusarium wilt. [ABSTRACT FROM AUTHOR]

Abstract: The horizontal component amplitudes of magnetograms recorded by ground-based observatories of the INTERMAGNET network have been used to analyze the global pattern variance of the solar diurnal variations. Those kinds of data present gaps in records and consequently we explore them via a time–frequency gapped wavelet algorithm. We propose a new approach to analyze magnetograms based on scale correlation. The results show that the magnetic records have a latitudinal dependence affected by the season of year and by the level of solar activity. We have found a disparity on the latitudinal response at Southern and Northern Hemispheres during solstices, which is expected due to the asymmetry of the Sq field. On the other hand at equinoxes, records from stations located at approximately the same latitude but at different longitudes presented peculiar dissimilarities. The achieved results suggest that quiet day patterns and the physical processes involved in their formation are strongly affected by the conductivity of the E-region, the geomagnetic field intensity and its configuration, and the thermospheric winds. [Copyright &y& Elsevier]

The objective of the present study was to establish whether exposure to temperatures of 55-70 °C results in eradication of the pathogen Clavibacter sepedonicus (Cs) in colonised potato tissue, in order to evaluate the efficiency of composting for disinfection of Cs-infected potato waste. Pre-sprouted potato tubers were inoculated and planted to produce Cs-colonised stem and tuber material. After incubation in temperature-controlled water baths, the infected potato tissue was analysed for the presence of culturable and pathogenic Cs. Additional experiments were performed with Cs-colonised potato stem tissue crushed and deaerated, thus simulating macerated stem tissue in the compost heap. To enable a comparison with bacterial cells that are not enclosed by their natural organic matrix, temperature treatments were applied to non-infected stem tissue crushed and deaerated, and spiked with freshly prepared Cs-suspensions. Cs settled inside colonised potato tissue, as well as Cs present as Cs-suspensions supplemented to potato tissue, was eradicated by exposure to heat, even after a treatment of 1 h at 55 °C, with the exception of one case in which the pathogen present in intact stem material escaped a treatment of 6 h at 60 °C, indicating that incidentally stems may provide niches in which the pathogen is protected against heat. [ABSTRACT FROM AUTHOR]

The plasma of the solar wind incident upon the Earth's magnetosphere can produce several types of geoeffective events. Among them, an important phenomenon consists of the interrelation of the magnetospheric-ionospheric current systems and the chargedparticle population of the Earth's Van Allen radiation belts. Ultra-low-frequency (ULF) waves resonantly interacting with such particles have been claimed to play a major role in the energetic particle flux changes, particularly at the outer radiation belt, which is mainly composed of electrons at relativistic energies. In this article, we use global magnetohydrodynamic simulations along with in situ and ground-based observations to evaluate the ability of two different solar wind transient (SWT) events to generate ULF (few to tens of mHz) waves in the equatorial region of the inner magnetosphere. Magnetic field and plasma data from the Advanced Composition Explorer (ACE) satellite were used to characterize these two SWT events as being a sector boundary crossing (SBC) on 24 September 2013, and an interplanetary coronal mass ejection (ICME) in conjunction with a shock on 2 October 2013. Associated with these events, the twin Van Allen Probes measured a depletion of the outer belt relativistic electron flux concurrent with magnetic and electric field power spectra consistent with ULF waves. Two ground-based observatories apart in 90° longitude also showed evidence of ULF-wave activity for the two SWT events. Magnetohydrodynamic (MHD) simulation results show that the ULF-like oscillations in the modeled electric and magnetic fields observed during both events are a result from the SWT coupling to the magnetosphere. The analysis of theMHD simulation results together with the observations leads to the conclusion that the two SWT structures analyzed in this article can be geoeffective on different levels, with each one leading to distinct ring current intensities, but both SWTs are related to the same disturbance in the outer radiation belt, i.e. a dropout in the relativistic electron fluxes. Therefore, minor disturbances in the solar wind parameters, such as those related to an SBC, may initiate physical processes that are able to be geoeffective for the outer radiation belt. [ABSTRACT FROM AUTHOR]

Four commercially available disinfection products were tested for their efficacy against Clavibacter michiganensis subsp. sepedonicus (Cms), causative agent of bacterial ring rot, on wooden potato storage crates. Each of these products represented a different class of biocide, i.e. organic acids (benzoic acid), peroxygenous compounds (potassium peroxysulfate), quaternary ammonium compounds (didecyldimethylammoniumchloride) and hypochlorite-generating compounds (sodium- p-toluenesulfochloramide). The target objects consisted of small wooden panels that were smeared with potato tuber pulp homogenized with a high inoculum of Cms. By dipping the inoculated panels into the product solutions and subsequent determination of the densities of colony-forming units, the relative efficacy of the products was established. The two products that exhibited the highest relative efficacy were studied for their disinfection performance when applied as cleaning agent in a conventional automated crate washer. The results showed that jet cleaning in a crate washer for 2 min using the authorised dose of the product containing sodium- p-toluenesulfochloramide is an effective method for disinfecting Cms-contaminated wooden potato crates. [ABSTRACT FROM AUTHOR]

In western Europe, Pectobacterium carotovorum subsp. brasiliense is emerging as a causal agent of blackleg disease. In field experiments in the Netherlands, the virulence of this pathogen was compared with strains of other Dickeya and Pectobacterium species. In 2013 and 2014, seed potato tubers were vacuum infiltrated with high densities of bacteria (106 CFU mL-1) and planted in clay soil. Inoculation with P. carotovorum subsp. brasiliense and P. atrosepticum resulted in high disease incidences (75-95%), inoculation with D. solani and P. wasabiae led to incidences between 5% and 25%, but no significant disease development was observed in treatments with P. carotovorum subsp. carotovorum, D. dianthicola or the water control. Co-inoculations of seed potatoes with P. carotovorum subsp. brasiliense and D. solani gave a similar disease incidence to inoculation with only P. carotovorum subsp. brasiliense. However, coinoculation of P. carotovorum subsp. brasiliense with P. wasabiae resulted in a decrease in disease incidence compared to inoculation with only P. carotovorum subsp. brasiliense. In 2015, seed potatoes were inoculated with increasing densities of P. carotovorum subsp. brasiliense, D. solani or P. atrosepticum (103-106 CFU mL-1). After vacuum infiltration, even a low inoculum density resulted in high disease incidence. However, immersion without vacuum caused disease only at high bacterial densities. Specific TaqMan assays were evaluated and developed for detection of P. carotovorum subsp. brasiliense, P. wasabiae and P. atrosepticum and confirmed the presence of these pathogens in progeny tubers of plants derived from vacuum-infiltrated seed tubers. [ABSTRACT FROM AUTHOR]

The effects of high-energy particle precipitation on mesospheric and stratospheric ozone have been investigated during the last decades. However, while these effects have been widely discussed for the auroral region, little is known about the role of the high-energy particle precipitation on the stratospheric composition and thermal structure in the tropical/subtropical region. Here we show that the spatial distribution of both the stratospheric ozone and temperature in the southern hemisphere matches the pattern of the Southern Hemisphere Magnetic Anomaly. We found that during the austral winter and spring, in the subtropical region (below 30°S), the reduction of the stratospheric ozone and temperature occurs systematically in the magnetic anomaly area. The differences between the temperatures inside the magnetic anomaly (60°W) and outside the anomaly (150°E) for 42.5°S from June to November are higher than 2 K. The maximum difference at this latitude is approximately 5.9 K and occurs in October during the austral spring. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the use of the running anaerobic sprint test (RAST) as a predictor of anaerobic capacity, compare it to the maximal accumulated oxygen deficit (MAOD) and to compare the RAST's parameters with the parameters of 30-s all-out tethered running on a treadmill. 39 (17.0 ± 1.4 years) soccer players participated in this study. The participants underwent an incremental test, 10 submaximal efforts [50-95 % of velocity correspondent to VO2MAX (vVO2MAX)] and one supramaximal effort at 110 % of vVO2MAX for the determination of MAOD. Furthermore, the athletes performed the RAST. In the second stage the 30-s all-out tethered running was performed on a treadmill (30-s all-out), and compared with RAST. No significant correlation was observed between MAOD and RAST parameters. However, significant correlations were found between the power of the fifth effort (P5) of RAST with peak and mean power of 30-s all-out (r = 0.73 and 0.50; p < 0.05, respectively). In conclusion, the parameters from RAST do not have an association with MAOD, suggesting that this method should not be used to evaluate anaerobic capacity. Although the correlations between RAST parameters with 30-s all-out do reinforce the RAST as an evaluation method of anaerobic metabolism, such as anaerobic power. [ABSTRACT FROM AUTHOR]

Abstract: We analyze the weak component of the localized temporal pattern variability of 3GHz solar burst observed by the Ondrejov radiospectrograph. A complex, short and weak impulsive sample from the time series was analyzed by applying a method based on the gradient pattern analysis and discrete wavelet decomposition. By analyzing canonical temporal variability patterns we show that the new method can reliably characterize the phenomenological dynamical process of short time series (N ⩽103 measurements) as the radio burst addressed here. In the narrowest sense, by estimating the mutual information distance in the gradient spectra, we show that the fluctuation pattern of the short and weak 3GHz impulsive solar burst, with energetic amplitudes <350 SFU, is closer to the intermittent and strong MHD turbulent variability pattern. [Copyright &y& Elsevier]

Solar systems complexity, multiscale, and nonlinearity are governed by numerous and continuous changes where the sun magnetic fields can successfully represent many of these phenomena. Thus, nonlinear tools to study these challenging systems are required. The dynamic system recurrence approach has been successfully used to deal with this kind challenge in many scientific areas, objectively improving the recognition of state changes, randomness, and degrees of complexity that are not easily identified by traditional techniques. In this work we introduce the use of these techniques in photospheric magnetogram series. We employ a combination of recurrence quantification analysis with a preprocessing denoising wavelet analysis to characterize the complexity of the magnetic flux emergence in the solar photosphere. In particular, with the developed approach, we identify regions of evolving magnetic flux and where they present a large degree of complexity, i.e., where predictability is low, intermittence is high, and low organization is present. [ABSTRACT FROM AUTHOR]