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Number of results: 647
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Abstract

The relationship between internal response-based reliability and conditionality is investigated for Gauss-Markov (GM) models with uncorrelated observations. The models with design matrices of full rank and of incomplete rank are taken into consideration. The formulas based on the Singular Value Decomposition (SVD) of the design matrix are derived which clearly indicate that the investigated concepts are independent of each other. The methods are presented of constructing for a given design matrix the matrices equivalent with respect to internal response-based reliability as well as the matrices equivalent with respect to conditionality. To analyze conditionality of GM models, in general being inconsistent systems, a substitute for condition number commonly used in numerical linear algebra is developed, called a pseudo-condition^number. Also on the basis of the SVD a formula for external reliability is proposed, being the 2-norm of a vector of parameter distortions induced by minimal detectable error in a particular observation. For systems with equal nonzero singular values of the design matrix, the formula can be expressed in terms of the index of internal response-based reliability and the pseudo-condition^number. With these measures appearing in explicit form, the formula shows, although only for the above specific systems, the character of the impact of internal response-based reliability and conditionality of the model upon its external reliability. Proofs for complementary properties concerning the pseudo-condition^number and the 2-norm of parameter distortions in systems with minimal constraints are given in the Appendices. Numerical examples are provided to illustrate the theory.
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Authors and Affiliations

Witold Prószyński
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Abstract

This paper proposes a modification of the classical process for evaluating the statistical significance of displacements in the case of heterogeneous (e.g. linear-angular) control networks established to deformation measurements and analysis. The basis for the proposed solution is the idea of local variance factors. The theoretical discussion was complemented with an example of its application on a simulated horizontal control network. The obtained results showed that the evaluation of the statistical significance of displacements in the case of heterogeneous control networks should be carried out using estimators of local variance factors.
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Authors and Affiliations

Krzysztof Nowel
Waldemar Kamiński
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Abstract

The paper describes the estimation of covariance parameters in least squares collocation (LSC) by the cross-validation (CV) technique called leave-one-out (LOO). Two parameters of Gauss-Markov third order model (GM3) are estimated together with a priori noise standard deviation, which contributes significantly to the covariance matrix composed of the signal and noise. Numerical tests are performed using large set of Bouguer gravity anomalies located in the central part of the U.S. Around 103 000 gravity stations are available in the selected area. This dataset, together with regular grids generated from EGM2008 geopotential model, give an opportunity to work with various spatial resolutions of the data and heterogeneous variances of the signal and noise. This plays a crucial role in the numerical investigations, because the spatial resolution of the gravity data determines the number of gravity details that we may observe and model. This establishes a relation between the spatial resolution of the data and the resolution of the gravity field model. This relation is inspected in the article and compared to the regularization problem occurring frequently in data modeling.
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Authors and Affiliations

Wojciech Jarmołowski
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Abstract

The aim of this study is to present an exemplary cartographic visualization of fi re hydrants data consisting of a set of thematic maps containing various information related to the location of hydrants, buildings and driveways in geographic space, and relationships existing between them. Identification of these relationships requires spatial analysis, and illustrating them requires the use of appropriate cartographic presentation methods. The study was conducted on a part of the city of Poznan using data on hydrants’ location and type collected and provided by the Fire Department. Geometric data, obtained using geoprocessing algorithms, were assigned appropriate symbols, which lets differentiate them qualitatively and quantitatively. An emphasis is placed on the use of adequate visual variables and on the cartographic communication efficiency. The result of the study is a cartographic visualization in the form of series of thematic maps arranged in a logical sequence, and providing information about the secured area. The thematic layers presenting the same area were arranged in different arrangements with maintenance of the reference layers, ensuring the ease of correlation. Such a cartographic visualization provides knowledge about the spatial distribution and diversity of objects and the relationships between them. It may be an important source of knowledge both at the identification stage and at the operational stage when conducting a fire fighting action.
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Authors and Affiliations

Łukasz Wielebski
Beata Medyńska-Gulij
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Abstract

Monitoring of permanent stations that make up the reference frame is an integral part of the geodesists work. Selection of reference stations is based on analysis of parameters characterizing them (hardware, coordinates’ stability, mounting, location). In this paper, we took into account phase residual as an indicator of unmodelled signal. Phase residuals were computed based on ASG-EUPOS and EPN observation processing. The results show the connection between the method of mounting the antenna and the residuals. We have reviewed multipath effect at ASG-EUPOS stations, and chosen those which are characterized by the highest value of phase residual. The results show that LC phase residual is a good factor to characterize site’s solutions’ reliability. For majority of sites RMS values were less than 10 mm. Modulations associated with multipath effect were observed for few ASG-EUPOS sites only. Phase residuals are distributed specifically for sites, which antennas are mounted on pillars (more common for EPN sites). For majority of analysed sites phase residual distribution was similar for different days and did not depend directly on atmosphere condition.
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Authors and Affiliations

Andrzej Araszkiewicz
Karolina Szafranek
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Abstract

One of the more important elements of spatial information infrastructure is the organisational structure defining the obligations and dependencies between stakeholders that are responsible for the infrastructure. Many SDI practitioners and theoreticians emphasise that its influence on the success or failure of activities undertaken is significantly greater than that of technical aspects. Being aware of the role of the organisational structure in the creating, operating and maintenance of spatial information infrastructure (SII), Polish legislators placed appropriate regulations in the Spatial Information Infrastructure Act, being the transposition of the INSPIRE Directive into Polish Law. The principal spatial information infrastructure stakeholders are discussed in the article and also the scope of cooperation between them. The tasks and relationships between stakeholders are illustrated in UML, in both the use case and the class diagram. Mentioned also are the main problems and obstructions resulting from imprecise legal regulations.
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Authors and Affiliations

Elżbieta Bielecka
Agnieszka Zwirowicz-Rutkowska
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Abstract

The article describes the process of creating 3D models of architectural objects on the basis of video images, which had been acquired by a Sony NEX-VG10E fixed focal length video camera. It was assumed, that based on video and Terrestrial Laser Scanning data it is possible to develop 3D models of architectural objects. The acquisition of video data was preceded by the calibration of video camera. The process of creating 3D models from video data involves the following steps: video frames selection for the orientation process, orientation of video frames using points with known coordinates from Terrestrial Laser Scanning (TLS), generating a TIN model using automatic matching methods. The above objects have been measured with an impulse laser scanner, Leica ScanStation 2. Created 3D models of architectural objects were compared with 3D models of the same objects for which the self-calibration bundle adjustment process was performed. In this order a PhotoModeler Software was used. In order to assess the accuracy of the developed 3D models of architectural objects, points with known coordinates from Terrestrial Laser Scanning were used. To assess the accuracy a shortest distance method was used. Analysis of the accuracy showed that 3D models generated from video images differ by about 0.06 ÷ 0.13 m compared to TLS data.
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Authors and Affiliations

Paulina Deliś
Michał Kędzierski
Anna Fryśkowska
Michalina Wilińska
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Abstract

Classification techniques have been widely used in different remote sensing applications and correct classification of mixed pixels is a tedious task. Traditional approaches adopt various statistical parameters, however does not facilitate effective visualisation. Data mining tools are proving very helpful in the classification process. We propose a visual mining based frame work for accuracy assessment of classification techniques using open source tools such as WEKA and PREFUSE. These tools in integration can provide an efficient approach for getting information about improvements in the classification accuracy and helps in refining training data set. We have illustrated framework for investigating the effects of various resampling methods on classification accuracy and found that bilinear (BL) is best suited for preserving radiometric characteristics. We have also investigated the optimal number of folds required for effective analysis of LISS-IV images.
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Authors and Affiliations

Pattathal Vijayakumar Arun
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Abstract

The paper presents the results of real time measurements of test geodetic control network points using the RTK GPS and RTX Extended technologies. The Trimble RTX technology uses the xFill function, which enables real measurements without the need for constant connection with the ASG EUPOS system reference stations network. Comparative analyses of the results of measurements using the methods were performed and they were compared with the test control network data assumed to be error-free. Although the Trimble RTX technology is an innovative measurement method which is rarely used now, the possibilities it provides in surveying works, including building geodetic control networks, are satisfactory and it will certainly contribute to improving the organisation of surveying works.
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Authors and Affiliations

Robert Krzyżek
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Abstract

Image registration is a key component of various image processing operations which involve the analysis of different image data sets. Automatic image registration domains have witnessed the application of many intelligent methodologies over the past decade; however inability to properly model object shape as well as contextual information had limited the attainable accuracy. In this paper, we propose a framework for accurate feature shape modeling and adaptive resampling using advanced techniques such as Vector Machines, Cellular Neural Network (CNN), SIFT, coreset, and Cellular Automata. CNN has found to be effective in improving feature matching as well as resampling stages of registration and complexity of the approach has been considerably reduced using corset optimization The salient features of this work are cellular neural network approach based SIFT feature point optimisation, adaptive resampling and intelligent object modelling. Developed methodology has been compared with contemporary methods using different statistical measures. Investigations over various satellite images revealed that considerable success was achieved with the approach. System has dynamically used spectral and spatial information for representing contextual knowledge using CNN-prolog approach. Methodology also illustrated to be effective in providing intelligent interpretation and adaptive resampling.
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Authors and Affiliations

Pattathal V. Arun
Sunil K. Katiyar
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Abstract

The paper attempts to determine an optimum structure of a directional measurement and control network intended for investigating horizontal displacements. For this purpose it uses the notion of entropy as a logarithmical measure of probability of the state of a particular observation system. An optimum number of observations results from the difference of the entropy of the vector of parameters X X ˆ H ' corresponding to one extra observation. An increment of entropy interpreted as an increment of the amount of information about the state of the system determines the adoption or rejection of another extra observation to be carried out.
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Authors and Affiliations

Maria Mrówczyńska
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Abstract

Amendment to the Act on special rules of preparation and implementation of investment in public roads resulted in an accelerated mode of acquisition of land for the development of roads. The decision to authorize the execution of road investment issued on its basis has several effects, i.e. determines the location of a road, approves surveying division, approves construction design and also results in acquisition of a real property by virtue of law by the State Treasury or local government unit, among others. The conducted study revealed that over 3 years, in this mode, the city of Krakow has acquired 31 hectares of land intended for the implementation of road investments. Compensation is determined in separate proceedings based on an appraisal study estimating property value, often at a distant time after the loss of land by the owner. One reason for the lengthy compensation proceedings is challenging the proposed amount of compensation, unregulated legal status of the property as well as imprecise legislation. It is important to properly develop geodetic and legal documentation which accompanies the application for issuance of the decision and is also used in compensation proceedings.
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Authors and Affiliations

Anna Trembecka
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Abstract

Modernization of lands and buildings register, which is run in Poland now, assumes capturing boundaries location data by various methods. They are: direct measurement preceded by determining of boundaries in the presence of parties, photogram- metric method, cartographic method, using existing maps being in analogue form. These methods not always assure accuracy. In the paper, an idea of correcting of location of boundary points which do not fulfil accuracy requirements has been presented. These corrections have been computed by assumption of invariability of parcel area revealed in register, so far. Such way of operation from one side would avoid many misunderstandings and difficulties by applying data collected in cadastre and from the other side will not disturb used procedures, which aim is to determine boundary of parcels with demanded accuracy.
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Authors and Affiliations

Paweł Hanus
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Abstract

The existing Polish gravity control (POGK) established in the last few years of 20th century according to the international standards is spanned on 12 absolute gravity stations surveyed with four different types of absolute gravimeters. Relative measurements performed by various groups on nearly 350 points of POGK with the use of LaCoste&Romberg (LCR) gravimeters were linked to those 12 stations. The construction of the network, in particular the limited number of non homogeneously distributed absolute gravity stations with gravity determined with different instruments in different epochs is responsible for systematic errors in g on POGK stations. The estimate of those errors with the use of gravity measurements performed in 2007-2008 is given and their possible sources are discussed. The development of absolute gravity measurement technologies, in particular instruments for precise field absolute gravity measurements, provides an opportunity to establish new type of gravity control consisting of stations surveyed with absolute gravimeters. New gravity control planned to be established in 2012-2014 will consist of 28 fundamental points (surveyed with the FG5 – gravimeter), and 169 base points (surveyed with the A10 gravimeter). It will fulfill recent requirements of geodesy and geodynamics and it will provide good link to the existing POGK. A number of stations of the new gravity control with precisely determined position and height will form the national combined geodetic network. Methodology and measurement schemes for both absolute gravimeters as well as the technology for vertical gravity gradient determinations in the new gravity control were developed and tested. The way to assure proper gravity reference level with relation to ICAG and ECAG campaigns as well as local absolute gravimeter comparisons are described highlighting the role of metrology in the project. Integral part of the project are proposals of re-computation of old gravity data and their transformation to a new system (as 2nd order network) as well as a definition of gravity system as “zero-tide” system. Seasonal variability of gravity has been discussed indicating that the effects of environmental changes when establishing modern gravity control with absolute gravity survey cannot be totally neglected .
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Authors and Affiliations

Jan Krynski
Tomasz Olszak
Marcin Barlik
Przemyslaw Dykowski
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Abstract

Surface water retention of leaves and fruits of apple ( Malus domestica Borkh.) and sweet cherry ( Prunus avium L.), was evaluated under controlled environmental conditions in order to determine the retention potential at different growth stages. Dipping and spraying, with and without non-ionic surfactant, were used as application systems. Water retention was expressed as the ratio between the weight difference of the organ before and post application and organ weight before application. Leaf water retention by dipping was 62 and 64% for ‘Royal Gala’ and ‘Fuji’ apples, respectively, and 37 and 50% by spraying. The surfactant tended to reduce foliar water retention by spraying on both species. An exponential reduction of fruit water retention was observed during their growth. Fruit dipping generated the highest water retention, with values of 50% at the earliest stage. Then, water retention stabilized at 1–2%, when the apples and sweet cherries diameter reached 25 and 15 mm, respectively, despite dipping or spraying. The surfactant tended to increase water retention at early fruit stages and to reduce it with fruit growth. These results can be useful for estimating the potential residue on leaves and fruits in apple and sweet cherry trees, in both the orchard (spraying) and the packing house (dipping).
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Authors and Affiliations

José Antonio Yuri
1
ORCID: ORCID
Miguel Palma
1
Álvaro Sepúlveda
1
Mariana Moya
1

  1. Centro de Pomáceas, Facultad de Ciencias Agrarias, Universidad de Talca, Talca, Chile
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Abstract

Entomopathogenic nematodes (EPNs) are promising as biocontrol agents for the most economically important insect pest attacking a wide range of host plants. Therefore, the aim of this work was to study the impact of four artificial diets and one natural food on numbers, weights, and total lipid content of the greater wax moth larvae, Galleria mellonella (Linnaeus) (Lepidoptera: Pyralidae) as well as the impact of these diets on the ability of nematode species Heterorhabditis bacteriophora and Steinernema carpocapsae to infect insects and multiply inside an insect host which had been reared on one of five different diets (D1, D2, D3, D4 and D5). The correlation between larvae weight and total lipid content, pathogenicity or multiplication of nematodes was also studied. The obtained results indicated that D2, D5 and D3 gave the highest growth or weights of larvae. The larvae produced weighed 3.71, 3.67 and 3.25 g from 50 g media, respectively. Statistically, larvae weights had a positive and significant correlation with the lipid content in larvae where r = 0.732. On the other hand, infective juveniles (IJs) of nematodes produced from insect hosts reared on D2 and D5 revealed more pathogenicity on larvae, since they caused the highest percent of mortality, 53.33 and 50.0% for H. bacteriophora, and 56.67 and 53.33% for S. carpocapsae, respectively. The total lipid content had a positive and highly significant correlation with the pathogenicity of the two nematode species where r = 0.97 and 0.971, respectively. Ultimately, the supplied foods of the artificial diets D2, D3 and natural beeswax (D5) gave the most suitable chance for developing insect growth and increasing the EPN quality and enhancing the potential of EPNs as biological control agents against different insect pests.
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Authors and Affiliations

Mona Ahmed Hussein
1
ORCID: ORCID
Hamdy Abdelnaby Salem
1
Sayed Hala
1
Salah Mahmoud
1

  1. Pests and Plant Protection Department, Agricultural and Biological Research Institute, National Research Center, Cairo, Egypt
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Abstract

The complete genome sequence of tomato leaf curl Palampur virus (ToLCPlV), that infects a papaya ( Carica papaya) plant, was determined. The virus genome was composed of 2,756 and 2,719 nucleotides (nt) in length, encoding all proteins required for replication, encapsidation and movement with the genome features typical of a bipartite begomovirus. Pairwise identity, derived using the Sequence Demarcation Tool (SDT), identified that the virus DNA A and DNA B shared maximum sequence identity 98–99% corresponding to the DNA A of ToLCPlV ([IR: Jir-T65X:08] JF501720) and 96–98% to the cognate partner DNA B of ToLCPlV ([IR: Jir1:T55P:07] FJ660423), respectively. The evolutionary relation using phylogenetic dendrograms of DNA A and DNA B genome components were clustered with ToLCPlV genomes of DNA A and DNA B of Iranian isolates. This study provides the first evidence of a bipartite ToLCPlV infecting papaya in the Sultanate of Oman and also indicates the requirement for more surveillance of this virus in Oman, as ToLCPlV is a major threat to tomato and other vegetable crops in South Asia (India and Pakistan) and in Iran.
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Authors and Affiliations

Muhammad Shafiq Shahid
1
Abdullah M. Al-Sadi
1

  1. Department of Plant Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-Khod, Oman
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Abstract

Maize dwarf mosaic virus (MDMV) is a serious and widespread virus pathogen of maize plants. This +ssRNA virus belongs to the Potyvirus genus in the Potyviridae family. Together with sugarcane mosaic virus (SCMV) it causes one of the most important viral diseases on maize crops in the world – maize dwarf mosaic. Both viruses are transmitted in the same non-persistent manner by several aphid species. They induce similar symptoms of leaf mosaic or mottling, stunting and a reduction in plant weight and grain yield. Available MDMV diagnostics include primarily commercialized enzyme-linked immunosorbent assays (ELISA) and reverse transcription-polymerase chain reactions (RT-PCR). Here, laborsaving reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay was optimized for identification of genetically different MDMV isolates. For this purpose, primer sets, MDMVF3/MDMVB3 and MDMVFIP/MDMVBIP amplifying fragments of coat protein coding sequence of MDMV, were used. The specificity of the reaction was verified using three MDMV (-P1, -Sp, -PV0802-DSMZ) and three SCMV (-P1, -PV0368- -DSMZ, -PV1207-DSMZ) isolates. Obtained products were visualised by DNA staining, electrophoretic separation as well as by real-time monitoring of the reaction. The sensitivity of RT-LAMP and conventional RT-PCR reactions was comparable. Both methods could detect virus as low as 550 fg · μl–1 of total RNA. This technique has application value for screening MDMV by phytosanitary services.
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Authors and Affiliations

Katarzyna Trzmiel
1
ORCID: ORCID
Beata Hasiów-Jaroszewska
1
ORCID: ORCID

  1. Department of Virology and Bacteriology, Institute of Plant Protection – National Research Institute, Poznan, Poland
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Abstract

Dasheen mosaic virus (DsMV) is one of the most important viral pathogens of aroids and can cause major economic losses for ornamental crops. Here, we present the detection and molecular characterisation of DsMV isolates originating from Monstera adansonii plants in Poland. Moreover, the genetic variability of DsMV isolates was analyzed based on the coat protein gene ( CP) of the Polish and other DsMV isolates described to date. The presence of DsMV was confirmed by transmission electron microscopy (TEM) and reverse transcription polymerase chain reaction (RT-PCR) with specific, diagnostic primers in three out of ten examined plants. To obtain full-length sequences of CP, two pairs of primers were designed and used in the RT-PCR. The specificity of obtained products was confirmed by Sanger sequencing. The obtained sequences of CP were compared with 44 other DsMV sequences retrieved from the GenBank. Analyses revealed that DsMV population is very diverse. The variability of DsMV isolates was confirmed by low sequence identity and pervasive recombination events. The phylogenetic analysis was performed based on 37 non-recombinant CP sequences. The maximum-likelihood reconstruction revealed that the Polish isolates are distinct and grouped separately from other DsMV isolates. Due to the high genetic diversity, detecting the virus could be difficult. Nonetheless disease management relies strongly on a fast and accurate identification of the causal agent. To our knowledge this is the first report of DsMV in Poland.
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Authors and Affiliations

Agnieszka Taberska
1
Julia Minicka
1
Daria Budzyńska
1
Beata Hasiów-Jaroszewska
1
ORCID: ORCID

  1. Department of Virology and Bacteriology, Institute of Plant Protection – National Research Institute, Poznań, Poland
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Abstract

In a previous study, the endophytic Bacillus velezensis NC318 was isolated from the rhizosphere of date palm and showed strong antifungal activity against the soil-borne plant pathogenic fungus, Sclerotium rolfsii Sacc, the causal agent of Southern blight. The potential of the Bacillus genus in the inhibition of plant pathogens is mainly due to the production of certain bioactive compounds. In the present study, secondary metabolites extracted from the cell-free supernatant of strain NC318 showed strong antifungal activity on the mycelial growth and germination of S. rolfsii sclerotia in vitro. With 50 μl of bioactive compounds crude extracts, the mycelial growth inhibition rate was 97% and any germination of sclerotia was reported. Chemical analysis of the secondary metabolite crude extracts performed by high performance liquid chromatography coupled with mass spectrometry (HPLC/MS), revealed that the secreted bioactive compounds belonged to the family of lipopeptides (iturin, fengycin, surfactin), polyketides (bacillaene, macrolactin, difficidin and bacilysin) and siderophores (bacillibactin). These results provide a better understanding of the biocontrol mechanism of the bacteria strain B. velezensis NC318 against the soil fungal pathogens, especially S. rolfsii root rot.
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Authors and Affiliations

Michelle Gaëlle Siméone Bidima
1
Noureddine Chtaina
1
Brahim Ezzahiri
1
Mohammed El Guilli
2
Ilham Barakat
1
ORCID: ORCID
Taha El Kamli
3

  1. Plant Protection Unit, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco
  2. Plant Protection Unit, National Institute of Agronomic Research, Rabat, Morocco
  3. Anti-Doping Control Laboratory, Hassan II Agronomic and Veterinary Institute, Kenitra, Morocco
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Abstract

Exotic plants, such as Eragrostis plana in southern Brazil, may cause significant problems in agriculture. This study aimed to elucidate the influence of E. plana rhizosphere soil on wheat germination and initial development. Bioassays with soil sampled from an infested agroecosystem were carried out using wheat as the target species. A factorial design was used, crossing soil from the horizontal and vertical distances from the E. plana tiller base and considering seasons as a blocking factor. The interaction between season and vertical and horizontal soil positions influenced normal wheat seed germination, with the lowest values (69%) observed in the winter bottom and intermediate soil positions. The highest abnormal seedling percentage (17.6%) was recorded in the summer middle vertical soil position. Dormant wheat seeds were higher (7%) in the spring bottom and distal soil positions. The season was the most important factor for germination, but hypocotyl, radicle, and total wheat seedling length also varied according to soil position. Shorter hypocotyls and seedlings were registered in the summer soil surface, while shorter radicles were observed in the proximal horizontal soil position in the same season. This variable response of wheat germination and seedling development to the infested soil demonstrated E. plana seasonality. The influence also varied according to the distance from the plant tiller base. These findings may be used to improve E. plana management in infested fields and to understand the mechanism of action of its allelochemicals in future research.
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Authors and Affiliations

Henrique von Hertwig Bittencourt
1
Lisandro Tomas da Silva Bonome
1
Edison Ferreira dos Santos Júnior
1
Alexandre Monkolski
2
Roger Paulo Mormul
3
Michelangelo Muzell Trezzi
4
Jakeline Galvão de França Monkolski
2

  1. Agronomy, Universidade Federal da Fronteira Sul, Laranjeiras do Sul, Brazil
  2. Biology, Universidade Federal da Fronteira Sul, Laranjeiras do Sul, Brazil
  3. Biology, Universidade Estadual de Maringá, Maringá, Brazil
  4. Agronomy, Universidade Tecnológica Federal do Paraná, Pato Branco, Brazil
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Abstract

During 2016–2020, a longitudinal bark canker was observed on walnut branches in some of the provinces of Iran. The symptoms appeared on one side of the branches. No visible symptoms were observed on the sapwood after removal of the bark using a blade. In order to detect a potential agent of these symptoms on walnut trees, collected samples were transferred to the laboratory for further investigation. After isolation and purification based on standard methods, a fungus was frequently isolated from symptomatic tissues. Morphological and molecular assays indicated that the responsible agent of this disease was Alternaria malorum, moreover, a pathogenicity test confirmed that A. malorum was pathogenic on walnut trees. To the best of our knowledge, this study represents the first attempt to identify A. malorum as a new causative agent of bark canker on walnut trees in the world.
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Authors and Affiliations

Shima Bagherabadi
1
Doustmorad Zafari
1

  1. Department of Plant Protection, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran
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Abstract

Salinity is one of the most significant constraints to crop production in dry parts of the world. This research emphasizes the beneficial effects of plant growth-promoting rhizobacterial isolates (PGPR) on the physiological responses of maize and wheat in a saline (NaCl) environment. Soil samples for the study were collected from a maize field in Baddi, Himachal Pradesh, India. Isolated bacterial strains were screened for salt (NaCl) tolerance and plant growth-promoting characters (i.e., indole acetic acid (IAA) production, siderophore production, amino cyclopropane-1-carboxylic acid (ACC) deaminase activity, hydrogen cyanide (HCN) production, and mineral phosphate solubilization). Screened bacterial isolates were further tested in pot experiments to examine their effects on wheat and maize growth. The treatments included five levels of bacterial inoculation (P0: control, P1: ACC deaminase positive + siderophore producer + NaCl tolerant bacteria, P2: mineral phosphate solubilizer + HCN producer + NaCl tolerant bacteria, P3: IAA producer + ACC deaminase positive + NaCl tolerant bacteria, P4: bacterial consortium, P5: Phosphomax commercial biofertilizer) and salt stress at 6 dS/m. Research findings found that exposure to a bacterial consortium led to the highest growth parameter in maize, including shoot length, root length, shoot and root dry weight followed by P2, P3, and P5 treatments at 6 dS/m salinity levels. However, P2 showed the best results for wheat at the same salinity levels, followed by P3, P4 and P5 treatments. P1 treatment did not show a significant result compared to control at 6dS/m salt level for both crops. The maximum proline content in maize and wheat was observed in P4 (23.28 μmol · g−1) and P2 (15.52 μmol · g−1) treatments, respectively, followed by P5 with Phosphomax biofertilizer. Therefore, the study proposed the application of growth-promoting bacterial isolates as efficient biofertilizers in the Baddi region of Himachal Pradesh, India.
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Authors and Affiliations

Arun Karnwal
1

  1. Department of Microbiology, School of Bioengineering and Biosciences, Lovely Professional University, Phagwara, India
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Abstract

Solanum elaeagnifolium Cav. is known to be one of the most invasive species worldwide. In this study, laboratory and greenhouse experiments were carried out to investigate the allelopathic properties of S. elaeagnifolium vegetative parts, root parts, fruit mucilage, and exudate extracts on plant communities and soil properties. In addition, the extract profiles of allelochemicals were quantified and their influence on soil properties and microorganisms was determined. Overall, the allelopathic performance of S. elaeagnifolium was established depending on the extract types, used concentrations, and target species. The doseresponse activity indicated that vegetative parts extract showed the greatest allelopathic potential followed by root parts extract. Subsequently, mucilage extract had a moderate inhibitory potential, while root exudates showed the least activity. The same trend with slight response was detected in soil properties of pH and EC properties. Polyphenols, in the range of 5.70–0.211 mg · g–1 and flavonols, in the range of 2.392–0.00 mg · g–1, were found in the analyzed samples extracted by ethyl acetate using LC-DAD-MS. The total phenol amount was 1.67 to 1.89 in the rhizosphere and 0.53 to 087 mg · g–1 in non-rhizosphere soils. Solanum elaeagnifolium exhibited a greater significant suppression of fungi count in both high and low-density areas than in rhizosphere bacteria. In conclusion, the strong and broadspectrum allelopathic potentials may enhance the ability of S. elaeagnifolium to impact seed germination and seedling growth of neighboring species. These biochemical weapons may play a critical role to facilitate their invasion and establishment in new agroecosystems.
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Authors and Affiliations

Mohamed A. Balah
1
Whaby M. Hassany
1
Abdelnasser A. Kobici
1

  1. Plant Protection Department, Desert Research Center, Matariya, Cairo, Egypt

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