scholarly journals The effect of cultivation conditions on growth, sporulation and formation of morphological structures of Topospora myrtilli (Feltg.) boerema

2012 ◽  
Vol 61 (2) ◽  
pp. 167-174
Author(s):  
Mariusz Szmagara ◽  
Ewa Zalewska

The growth of <i>Topospora myrtilli</i> isolates, obtained in the years 2001-2003, was studied on PDA medium at -10, +2, +6, +12, +18, +22 and +28°C. The growth and sporulation of the isolates were observed at +22°C on the following culture media: PDA, maltose - MA and mineral - MSA, as well as on two versions of oat media, one containing 20 g of oat flakes per litre (OA-20), and the other containing 50 g of oat flakes per litre (OA-50). The observations of the linear growth of colonies of the studied strains were carried out during a period of 21 days, whereas the formation of morphological structures until the 52<sup>nd</sup> day of cultivation. It was found that <i>T. myrtilli</i> can grow and sporulate in a wide range of temperature, even at +2°C. The pathogen growth activates with the increase of temperature, up to the optimal temperature, i.e. from +18°C to +22°C. The increase of temperature to +28°C did not favour the mycelium growth and prevents pathogen sporulation. PDA, OA-20, OA- 50 and MA media can be considered to be the most suitable for the growth and development of <i>T. myrtilli</i>, due to the intensive growth and formation of typical macro- and microscopic features. It is necessary to emphasise the great usefulness of oat medium, especially OA-50, for the cultivation of <i>Topospora myrtilli</i>, in the aspect of sporulation of the fungus. It was found that mineral medium is unsuitable due to the formation of mycelium with an untypical structure and colouration as well as late conidial sporulation.

2012 ◽  
Vol 60 (2) ◽  
pp. 109-129 ◽  
Author(s):  
I. Csöndes

Macrophomina phaseolina (Tassi) Goidanich can cause serious yield losses in several plant species. Investigations were made on the colony morphology of fifty Macrophomina phaseolina isolates from Hungary, one from Spain and two from Serbia on six different culture media to detect differences between the isolates. The fungus exhibited the most intensive growth on maize-flour agar, followed by the Sabouraud-glucose, maltextract, potato-dextrose, Czapek-Dox and watery agar media. Investigations on the macromorphology of the isolates revealed different extents of aerial mycelia formation and differences in the zonal structure of microsclerotial formation on the individual media. One isolate (Mp 38) turned the Sabouraud-glucose agar medium pale pink. Investigations on the micromorphology of the cultures showed that the isolates also varied with respect to microsclerotial characters (size, shape and production of microsclerotia). The microsclerotia of this fungal pathogen had the greatest diameter (averaging 135.31 μm) on Sabouraud-glucose agar medium. This study was the first in Hungary to prove that Macrophomina phaseolina could be grown on nutrient-deficient watery agar, suggesting that it can tolerate a wide range of ecological circumstances.


2012 ◽  
Vol 60 (1) ◽  
pp. 101-105 ◽  
Author(s):  
Anna Jarecka ◽  
Alicja Saniewska

The effect of D,L-<i>β</i>-aminobutyric acid (BABA) on the growth and development of the root system and the development of fusariosis on tulip bulbs cv. Apeldoorn infected by <i>Fusarium oxysporum</i> f. sp. <i>tulipae</i> (F.ox.t. 218) was studied. The length and fresh weight of roots, the development of fusariosis on bulbs and the linear growth of mycelium of F.ox.t. 218 on PDA medium were measured. Preventively used BABA at a concentration of 100, 250 and 300 µg·cm<sup>-3</sup> for soaking uncooled and cooled tulip bulbs greatly inhibited the development of fusariosis on the root system; the length and fresh weight of roots were similar to those of the bulbs not inoculated with F.ox.t. 218. At a concentration of 100 µg·cm<sup>-3</sup>;, BABA used for soaking bulbs limited the development of fusariosis on scales in about 50% and the concentration of 200 µg·cm<sup>-3</sup> totally inhibited the disease symptoms induced by F.ox.t. 218. At a concentration of 100 - 1000 µg·cm<sup>-3</sup>, BABA did not inhibit the mycelium growth of F.ox.t. 17 and F.xo.t. 218 on PDA medium. This study suggests that BABA protects tulip roots and bulb scales against <i>F. oxysporum</i> f. sp. <i>tulipae</i> by inducing resistance in these organs and has no direct influence on the pathogen.


2009 ◽  
Vol 52 (5) ◽  
pp. 1091-1098
Author(s):  
Ilisandra Zanandrea ◽  
Marcos Antonio Bacarin ◽  
Eugenia Jacira Bolacel Braga ◽  
Valmor João Bianchi ◽  
José Antonio Peters

The aim of the present study was to evaluate the growth and development of apple rootstock shoots submitted to different photon flux densities (7, 14, 21 and 60 µmol m-2 s-1) and three culture media. The best photon flux for maximizing growth, number of shoots and leaves was 14 µmol m-2 s-1, which also resulted in the highest values of chloroplastic pigments. On the other hand, the highest photon flux (60 µmol m-2 s-1) decreased significantly these parameters. Medium with reduced sucrose concentration did not affect the analyzed parameters, enabling an efficient multiplication of the cultivar with only 1% of sucrose.


2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.


2018 ◽  
Vol 8 (4) ◽  
pp. 28-33
Author(s):  
Mao Nguyen Van ◽  
Thao Le Thi Thu

Background: In practice it was difficult or impossible to have a correct diagnosis for the lymphoid proliferation lesions based on only H.E standard histopathology. In addition to histopathology, the application of immunohistochemistry was indispensable for the definitive diagnosis of the malignant or benign tumours and the origin of the tumour cells as well. Objectives: 1. To describe the gross and microscopic features of the suspected lesions of lymphoma; 2. To asses the expression of some immunologic markers for the diagnosis and classification of the suspected lesions of lymphoma. Materials and Method: Cross-sectional research on 81 patients diagnosed by histopathology as lymphomas or suspected lesions of lymphoma, following with immunohistopathology staining of 6 main markers including LCA, CD3, CD20, Bcl2, CD30 and AE1/3. Results: The most site was lymph node 58.1% which appeared at cervical region 72.3%, then the stomach 14.9% and small intestine 12.4%. The other sites in the body were met with lower frequency. Histopathologically, the most type of the lesions was atypical hyperplasia of the lymphoid tissue suspecting the lymphomas 49.4%, lymphomas 34.5%, the other diagnoses were lower including inflammation, poor differentiation carcinoam not excluding the lymphomas, lymphomas differentiating with poor differentiation carcinomas. Immunohistochemistry showed that, LCA, CD3, CD20, Bcl2, CD30 and AE1/3 were all positive depending on such type of tumours. The real lymphomas were 48/81 cases (59.3%), benign ones 35.8% and poor differentiated carcinomas 4.9%. Conclusion: Immunohistochemistry with 6 markers could help to diagnose correctly as benign or malignant lesions, classify and determine the origin of the tumour cells as lymphocytes or epithelial cells diagnosed by histopathology as lymphomas or suspected lesions of lymphomas. Key words: histopathology, immunohistochemistry, lymphomas, poor differentiated carcinomas, hyperplasia, atypicality


2020 ◽  
Vol 24 ◽  
Author(s):  
Bubun Banerjee ◽  
Gurpreet Kaur ◽  
Navdeep Kaur

: Metal-free organocatalysts are becoming an important tool for the sustainable developments of various bioactive heterocycles. On the other hand, during last two decades, calix[n]arenes have been gaining considerable attention due to their wide range of applicability in the field of supramolecular chemistry. Recently, sulfonic acid functionalized calix[n] arenes are being employed as an efficient alternative catalyst for the synthesis of various bioactive scaffolds. In this review we have summarized the catalytic efficiency of p-sulfonic acid calix[n]arenes for the synthesis of diverse biologically promising scaffolds under various reaction conditions. There is no such review available in the literature showing the catalytic applicability of p-sulfonic acid calix[n]arenes. Therefore, we strongly believe that this review will surely attract those researchers who are interested about this fascinating organocatalyst.


Toxins ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 645 ◽  
Author(s):  
Hamed K. Abbas ◽  
Nacer Bellaloui ◽  
Cesare Accinelli ◽  
James R. Smith ◽  
W. Thomas Shier

Charcoal rot disease, caused by the fungus Macrophomina phaseolina, results in major economic losses in soybean production in southern USA. M. phaseolina has been proposed to use the toxin (-)-botryodiplodin in its root infection mechanism to create a necrotic zone in root tissue through which fungal hyphae can readily enter the plant. The majority (51.4%) of M. phaseolina isolates from plants with charcoal rot disease produced a wide range of (-)-botryodiplodin concentrations in a culture medium (0.14–6.11 µg/mL), 37.8% produced traces below the limit of quantification (0.01 µg/mL), and 10.8% produced no detectable (-)-botryodiplodin. Some culture media with traces or no (-)-botryodiplodin were nevertheless strongly phytotoxic in soybean leaf disc cultures, consistent with the production of another unidentified toxin(s). Widely ranging (-)-botryodiplodin levels (traces to 3.14 µg/g) were also observed in the roots, but not in the aerial parts, of soybean plants naturally infected with charcoal rot disease. This is the first report of (-)-botryodiplodin in plant tissues naturally infected with charcoal rot disease. No phaseolinone was detected in M. phaseolina culture media or naturally infected soybean tissues. These results are consistent with (-)-botryodiplodin playing a role in the pathology of some, but not all, M. phaseolina isolates from soybeans with charcoal rot disease in southern USA.


2021 ◽  
Vol 15 (5) ◽  
pp. 1-32
Author(s):  
Quang-huy Duong ◽  
Heri Ramampiaro ◽  
Kjetil Nørvåg ◽  
Thu-lan Dam

Dense subregion (subgraph & subtensor) detection is a well-studied area, with a wide range of applications, and numerous efficient approaches and algorithms have been proposed. Approximation approaches are commonly used for detecting dense subregions due to the complexity of the exact methods. Existing algorithms are generally efficient for dense subtensor and subgraph detection, and can perform well in many applications. However, most of the existing works utilize the state-or-the-art greedy 2-approximation algorithm to capably provide solutions with a loose theoretical density guarantee. The main drawback of most of these algorithms is that they can estimate only one subtensor, or subgraph, at a time, with a low guarantee on its density. While some methods can, on the other hand, estimate multiple subtensors, they can give a guarantee on the density with respect to the input tensor for the first estimated subsensor only. We address these drawbacks by providing both theoretical and practical solution for estimating multiple dense subtensors in tensor data and giving a higher lower bound of the density. In particular, we guarantee and prove a higher bound of the lower-bound density of the estimated subgraph and subtensors. We also propose a novel approach to show that there are multiple dense subtensors with a guarantee on its density that is greater than the lower bound used in the state-of-the-art algorithms. We evaluate our approach with extensive experiments on several real-world datasets, which demonstrates its efficiency and feasibility.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1461
Author(s):  
Shun-Hsin Yu ◽  
Jen-Shuo Chang ◽  
Chia-Hung Dylan Tsai

This paper proposes an object classification method using a flexion glove and machine learning. The classification is performed based on the information obtained from a single grasp on a target object. The flexion glove is developed with five flex sensors mounted on five finger sleeves, and is used for measuring the flexion of individual fingers while grasping an object. Flexion signals are divided into three phases, and they are the phases of picking, holding and releasing, respectively. Grasping features are extracted from the phase of holding for training the support vector machine. Two sets of objects are prepared for the classification test. One is printed-object set and the other is daily-life object set. The printed-object set is for investigating the patterns of grasping with specified shape and size, while the daily-life object set includes nine objects randomly chosen from daily life for demonstrating that the proposed method can be used to identify a wide range of objects. According to the results, the accuracy of the classifications are achieved 95.56% and 88.89% for the sets of printed objects and daily-life objects, respectively. A flexion glove which can perform object classification is successfully developed in this work and is aimed at potential grasp-to-see applications, such as visual impairment aid and recognition in dark space.


Genetics ◽  
2002 ◽  
Vol 161 (3) ◽  
pp. 1247-1255 ◽  
Author(s):  
Eiji Nambara ◽  
Masaharu Suzuki ◽  
Suzanne Abrams ◽  
Donald R McCarty ◽  
Yuji Kamiya ◽  
...  

Abstract The plant hormone abscisic acid (ABA) controls many aspects of plant growth and development under a diverse range of environmental conditions. To identify genes functioning in ABA signaling, we have carried out a screen for mutants that takes advantage of the ability of wild-type Arabidopsis seeds to respond to (−)-(R)-ABA, an enantiomer of the natural (+)-(S)-ABA. The premise of the screen was to identify mutations that preferentially alter their germination response in the presence of one stereoisomer vs. the other. Twenty-six mutants were identified and genetic analysis on 23 lines defines two new loci, designated CHOTTO1 and CHOTTO2, and a collection of new mutant alleles of the ABA-insensitive genes, ABI3, ABI4, and ABI5. The abi5 alleles are less sensitive to (+)-ABA than to (−)-ABA. In contrast, the abi3 alleles exhibit a variety of differences in response to the ABA isomers. Genetic and molecular analysis of these alleles suggests that the ABI3 transcription factor may perceive multiple ABA signals.


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