INCIDÊNCIA E CARACTERIZAÇÃO MORFOLÓGICA DE Alternaria alternata E Bipolaris bicolor EM SEMENTES DE TRIGO ‘BRS 264’

The seeds are considered important spread vehicles of pathogens.This study aimed to quantify the incidence of A. alternata and B. bicolor in wheat seeds ‘BRS 264’ and to perform morphological characterization of these fungi. Therefore, four sanitary evaluations were performed in gerbox transparent acrylic boxes. In order to inhibit germination, the seeds wereincubated in a BOD at 25ºC and 12-hour light period for 24 hours and, then, transferred to freezer at -20ºC and dark period for 24 hours. Just after, the seeds were incubated in BOD chamber at 25ºC and 12-hour light period during 8 days, which the incidence was estimated daily. Then, semi-permanent slide mountings were prepared for subsequent capturing images and measurement of fungi structures by obtaining 30 measurements of each structural component evaluated under a Leica DM500 light microscope, using the LAS EZ 2.0 (100x) software. The results concerning fungal structures and incidence were submitted to variance and regression analysis, respectively. From this, it was possible to confirm A. alternata and B. bicolor presence through morphological characterization, which presented 41.5 and 16.5% of incidence on the seeds at 8 days of evaluation, respectively.

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Cephaleuros virescens in Brazilian Mahogany: Algae Parasitic Disease Threatening an Important Reforestation Tree

Journal of Agricultural Studies ◽

10.5296/jas.v8i1.16093 ◽

2020 ◽

Vol 8 (1) ◽

pp. 439

Author(s):

Fabiola T. Pereira ◽

Wanderson S. Santos ◽

Gesiane R. Guimarães ◽

Elizabeth A. A. Duarte ◽

Thiago A. S. Oliveira ◽

...

Keyword(s):

Molecular Identification ◽

Light Microscope ◽

Nuclear Gene ◽

Morphological Characterization ◽

Parasitic Disease ◽

Forest Species ◽

Great Capacity ◽

Plant Parasitic ◽

Different Parts

The forest species are frequent targets of diseases. In this context, the plant-parasitic algae comprise a separate group in this process, including the algae genus Cephaleuros, which attacks mahogany cultivars. The objective of this work was to accomplish the molecular and morphological characterization of the causal agent of algae spots occurring in Brazilian mahogany (Swietenia macrophylla). Somatic and reproductive algae structures contained in lesions on the leaves had the DNA extracted and amplified by primers 18SHf and 18SLr of the rRNA nuclear gene 18S. Then, the amplicons were purified and sequenced. The algae structures too were characterized under light microscope. In addition, a total of 12 injured leaves located in the lower third of each attacked tree were randomly extracted for lesion characterization according to its size and number. After algae structures measurements, sporangiophores and sporangia had 260.2 x 12.9 μm and 25 x 18.8 μm. These measurements, combined with the molecular identification, indicated that the algae found in Brazilian mahogany leaves is C. virescens. Attacked leaves showed an average of 33 lesions, 60% of which were smaller than 2 mm in diameter, which shows great capacity of the pathogen to reach different parts of the foliar limb. These measurements, combined with molecular identification, confirmed the algae found in Brazilian mahogany leaves to be C. virescens.

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Morphological Characterization of Mycobacteriophage R1

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051281 ◽

1974 ◽

Vol 32 ◽

pp. 254-255

Author(s):

B. L. Soloff ◽

T. A. Rado

Keyword(s):

Carbon Source ◽

Stationary Phase ◽

Growth Phase ◽

Minimal Medium ◽

Morphological Characterization ◽

Logarithmic Growth Phase ◽

Complete Lysis ◽

Lysogenic Culture ◽

Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

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Immunocytochemical studies on the behavior of RuBisCO and LHCP II during the cell cycle of synchronized Euglena gracilis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160868 ◽

1990 ◽

Vol 48 (3) ◽

pp. 662-663

Author(s):

Tetsuaki Osafune ◽

Shuji Sumida ◽

Tomoko Ehara ◽

Eiji Hase ◽

Jerome A. Schiff

Keyword(s):

Cell Cycle ◽

Immunoelectron Microscopy ◽

Growth Phase ◽

Euglena Gracilis ◽

Dark Period ◽

Light Period ◽

Carboxylase Activity ◽

Immunocytochemical Studies ◽

Lhcp Ii

Changes in the morphology of pyrenoid and the distribution of RuBisCO in the chloroplast of Euglena gracilis were followed by immunoelectron microscopy during the cell cycle in a light (14 h)- dark (10 h) synchronized culture under photoautotrophic conditions. The imrnunoreactive proteins wereconcentrated in the pyrenoid, and less densely distributed in the stroma during the light period (growth phase, Fig. 1-2), but the pyrenoid disappeared during the dark period (division phase), and RuBisCO was dispersed throughout the stroma. Toward the end of the division phase, the pyrenoid began to form in the center of the stroma, and RuBisCO is again concentrated in that pyrenoid region. From a comparison of photosynthetic CO2-fixation with the total carboxylase activity of RuBisCO extracted from Euglena cells in the growth phase, it is suggested that the carboxylase in the pyrenoid functions in CO2-fixation in photosynthesis.

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Morphological Characterization of Rhinacanthus Species of Sri Lanka

Planta Medica ◽

10.1055/s-0030-1251769 ◽

2010 ◽

Vol 76 (05) ◽

Author(s):

APPR Amarasinghe ◽

RP Karunagoda ◽

DSA Wijesundara

Keyword(s):

Sri Lanka ◽

Morphological Characterization

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Density and morphological characterization of bacteria in integrated and exclusive production systems

Scientific Electronic Archives ◽

10.36560/13920201194 ◽

2020 ◽

Vol 13 (11) ◽

pp. 1

Author(s):

A. R. B. Zanco ◽

A. Ferreira ◽

G. C. M. Berber ◽

E. N. Gonzaga ◽

D. C. C. Sabino

Keyword(s):

Bacterial Community ◽

Rainy Season ◽

Production Systems ◽

Cropping System ◽

Morphological Characterization ◽

Native Forest ◽

Exclusive Production ◽

Colony Forming Units

The different integrated production systems can directly interfere with its bacterial community. The present study aimed to assess density, bacterial diversity and the influence of dry and rainy season in different integrated and an exclusive production system. The fallow and a native forest area was assessed to. Samples were collected in 2012 March and September. The isolation were carried out into Petri dishes containing DYGS medium. The number of colony forming units (CFU) was counted after 48 hours and. The bacterial density ranged between 106 and 107 CFU g-1 soil. The crop system affected the dynamics of the bacterial community only in the rainy season. The rainy season showed greater density of total bacteria when compared to the dry period regardless of the cropping system. The dendrograms with 80 % similarity showed thirteen and fourteen groups in the rainy and dry seasons. Isolates with the capacity to solubilize phosphate in vitro were obtained from all areas in the two seasons, but this feature has been prevalent in bacteria isolated during the rainy season

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Characterization of Antibacterial-Producing Endophytic Fungi of Syzygiumpolyanthum Leaves

Infectious Disorders - Drug Targets ◽

10.2174/1871526519666181226123541 ◽

2020 ◽

Vol 20 (4) ◽

pp. 448-454

Author(s):

Rahmita Burhamzah ◽

Gemini Alam ◽

Herlina Rante

Keyword(s):

Molecular Characterization ◽

Endophytic Fungi ◽

Morphological Characterization ◽

Test Method ◽

Analysis Method ◽

Nitrogen Base ◽

Rdna Genes ◽

Antibacterial Screening ◽

Planting Method

Background: Endophytic fungi live in plants’ tissue and can produce the same bioactive compounds as its host plant produces. Syzygiumpolyanthum leaves have known to be one of the antibacterial compound producers. Aim and Objective: This study aimed to characterize morphologically, microscopically, and molecularly the antibacterial-producing endophytic fungi of Syzygiumpolyanthum leaves. Methods: The isolation of endophytic fungi was done by fragment planting method on PDA medium. The antibacterial screening was performed using the antagonistic test as the first screening followed by the disc diffusion test method. The morphological characterization was based on isolate’s mycelia color, growth pattern, margin, and surface texture of the colony, while the microscopic characterization was based on its hyphae characteristics. The molecular characterization of the isolate was done by nitrogen base sequence analysis method on nucleotide constituent of ITS rDNA genes of the isolate. Results: The results found that isolate DF1 has antibacterial activity against E.coli, S.aureus, P.acne, and P.aeruginosa, with the greatest inhibition at 10% concentration of broth fermentation extract on S.aureus with a diameter of inhibition of 13.77 mm. Conclusion: Based on macroscopic, microscopic, and molecular characterization, DF1 isolate is similar to Ceriporialacerate.

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Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽

10.3390/membranes11050303 ◽

2021 ◽

Vol 11 (5) ◽

pp. 303

Author(s):

Rokayya Sami ◽

Schahrazad Soltane ◽

Mahmoud Helal

Keyword(s):

Ph Value ◽

Silica Nanoparticle ◽

Morphological Characterization ◽

Aerobic Bacteria ◽

Nano Materials ◽

Elongation At Break ◽

Stable Suspension ◽

Average Size ◽

Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

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