Petri Dishes Research Articles

Serial block-face scanning electron microscopy of adherent cells on thin plastic substrate

Abstract Serial block-face (SBF) scanning electron microscopy (SEM) is used for imaging the entire internal ultrastructure of cells, tissue samples or small organisms. Here, we present a workflow for SBF SEM of adherent cells, such as Giardia parasites and HeLa cells, attached to the surface of a plastic culture dish, which preserves the interface between cells and plastic substrate. Cells were embedded in situ on their substrate using silicone microwells and were mounted for cross-sectioning which allowed SBF imaging of large volumes and many cells. A standard sample preparation and embedding protocol for thin section electron microscopy provided already sufficient resolution and image quality to visualize larger structures. To improve resolution and image quality of SBF imaging, we stepwise tested modifications of the protocol, such as the moderate increase of the heavy metal content of the sample. Modifications of the embedding by either the reduction of the resin layer (minimal embedding) or the addition of silver colloid to the resin were evaluated at high and low vacuum imaging conditions. The optimized sample preparation protocol is very similar to the standard preparation protocol for thin section electron microscopy, so that the samples can also be used for this application. The protocol applies a higher concentration of osmium tetroxide, a higher temperature for heavy metal incubation and an additional lead en bloc staining. In summary, the presented workflow provides a generic and adaptable solution for studying adherent cells by SBF SEM.

Evaluation of indigenous isolates of Beuveria bassiana (Balsamo) Vuillemin (Deuteromycotina: Hyphomycetes) against the cotton aphid Aphis gossypii Glover

AbstractThe cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is one of the most important pests and causes major damage to cultivated plants in Turkey. It has recently become a serious problem in Antalya (southwestern Turkey) due to its high resistance to insecticides used. To address this problem, the present study aimed to evaluate the pathogenicity of five indigenous Beuveria bassiana (Balsamo) Vuillemin (Deuteromycotina: Hyphomycetes) isolates (BbFn-2, BbKm-2, BbSr-2, BbDs-4, and BbDm-2) with high virulence in previous studies against the pest. All the isolates were tested at five different conidial concentrations (1 × 105, 1 × 106, 1 × 107, 1 × 108 and 1 × 109 conidia mL−1) against the nymphs and adults of A. gossypii using Petri dish and pot trials in the laboratory. The results from the bioassays showed that virulence of the isolates increased significantly with elapsed time up to 10 days after inoculation. All five B. bassiana isolates at the highest concentration (1 × 109 conidia mL−1) caused mortalities ranged from 83.3% to 100% in both nymphs and adults 10 days post-treatment. While the LT50 and LT95 values of the isolates were 1.72–2.12 days and 4.81–8.49 days, respectively, for the nymphs, they were calculated for the adults as 1.65–2.54 days and 4.66–12.93 days, respectively. Results of the phylogenetic analysis showed that these five B. bassiana isolates had high similarities (ranging from 99 to 100%) with the other B. bassiana isolates in GenBank. All the results suggest that above-mentioned five indigenous B. bassiana isolates have significant biocontrol potential against A. gossypii.

Proliferation of SH-SY5Y neuroblastoma cells on confined spaces

Background:Microfluidics offers precise drug delivery and continuous monitoring of cell functions, which is crucial for studying the effects of toxins and drugs. Ensuring proper cell growth in these space-constrained systems is essential for obtaining consistent results comparable to standard Petri dishes. New method:We investigated the proliferation of SH-SY5Y cells on circular polycarbonate chambers with varying surface areas. SH-SY5Y cells were chosen for their relevance in neurodegenerative disease research. Results:Our study demonstrates a correlation between the chamber surface area and SH-SY5Y cell growth rates. Cells cultured in chambers larger than 10 mm in diameter exhibited growth comparable to standard 60-mm dishes. In contrast, smaller chambers significantly impeded growth, even at identical seeding densities. Similar patterns were observed for HeLaGFP cells, while 16HBE14σ cells proliferated efficiently regardless of chamber size. Additionally, SH-SY5Y cells were studied in a 12-mm diameter sealed chamber to assess growth under restricted gas exchange conditions. Comparison with existing methods:Our findings underscore the limitations of small chamber sizes in microfluidic systems for SH-SY5Y cells, an issue not typically addressed by conventional methods. Conclusions:SH-SY5Y cell growth is highly sensitive to spatial constraints, with markedly reduced proliferation in chambers smaller than 10 mm. This highlights the need to carefully consider chamber size in microfluidic experiments to achieve cell growth rates comparable to standard culture dishes. The study also shows that while SH-SY5Y and HeLaGFP cells are affected by chamber size, 16HBE14σ cells are not. These insights are vital for designing effective microfluidic systems for bioengineering research.

Assessment of the Behaviors of an In Vitro Brain Model On-Chip under Shockwave Impacts.

Herein we report the assessment of the effects of shockwave (SW) impacts on adult rat hippocampal progenitor cell (AHPC) neurospheres (NSs), which are used as in vitro brain models, for enhancing our understanding of the mechanisms of traumatic brain injury (TBI). The assessment has been achieved by using culture dishes and a new microchip. The microchip allows the chemicals released from the brain models cultured inside the cell culture chamber under SW impacts to diffuse to the nanosensors in adjacent sensor chambers through built-in diffusion barriers, which are used to prevent the cells from entering the sensor chambers, thereby mitigating the biofouling issues of the sensor surface. Experiments showed the negative impact of the SW on the viability, proliferation, and differentiation of the cells within the NSs. A qPCR gene expression analysis was performed and appeared to confirm some of the immunocytochemistry (ICC) results. Finally, we demonstrated that the microchip can be used to monitor lactate dehydrogenase (LDH) released from the AHPC-NSs subjected to SW impacts. As expected, LDH levels changed when AHPC-NSs were injured by SW impacts, verifying this chip can be used for assessing the degrees of injuries to AHPC-NSs by monitoring LDH levels. Taken together, these results suggest the feasibility of using the chip to better understand the interactions between SW impacts and in vitro brain models, paving the way for potentially establishing in vitro TBI models on a chip.

Potential of Aqueous Extracts From Root Organs of Ratoon Plants Sorghum Cultivated on Inceptisols Soil as Bioherbicide

Purpose: This study aims to determine the best inhibitory effect of water extracts from the ratoon root organs of sorghum plants grown on Inceptisol soil on the germination of test plants. Methodology: The study used a single-factor completely randomized design with four treatments: control, Numbu roots, Super 1 roots, and Suri 4 roots. The experiment units were petri dishes, and the experiment was repeated four times. The bioassay method in petri dishes was applied, with 10 ml of water extract added to each dish, and 25 Vima 1 mung bean seeds were incubated for three days. Results: The water extracts from the ratoon roots of Numbu and Suri 4, as well as all other sorghum ratoon root extracts, significantly inhibited the germination of test plants compared to the control. Findings: Sorghum ratoon root extracts exhibit potent bioherbicidal properties. Novelty: This research provides insights into the allelopathic potential of different sorghum varieties. Originality: The study offers a detailed analysis of the bioherbicidal effects of sorghum ratoon root extracts on seed germination. Conclusions: Water extracts from sorghum ratoon roots, especially Numbu and Suri 4, effectively inhibit test plant germination. Type of Paper: Empirical Research Article

Searching for Chemical Agents Suppressing Substrate Microbiota in White-Rot Fungi Large-Scale Cultivation.

Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) in vitro. Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and Candida spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff.

Environmental Impact of Choline Dihydrogenphosphate ([Chol][DHP]) on Seed Germination and Soil Microbial Activity

The applicability of ionic liquids has grown exponentially over the last few decades. This growth is due to the easy modification of these compounds formed by ions, through the proper choice of both moieties, and the possibility of introducing functional groups into their cations and anions. However, studies of their toxicity and effects on the environment remain scarce. This study analyses firstly the response to adding different concentrations of choline dihydrogen phosphate to the germination of seeds of eight plant species. It also examines the microbial population and the respiration of two soils with contrasting organic matter contents. Seeds were incubated in a Petri dish in a Phytotron with a photoperiod of 16 h under light at 24 °C and 8 h in darkness at 16 °C. The activity of microbial populations of untreated and treated soils was analysed by isothermal microcalorimetry at 25 °C. Basal soil respiration kinetics were measured at optimal moisture (80% of field water retention capacity) and temperature (25 °C) over 10 days. The results indicate that this compound has diverse effects on the different endpoints. Nevertheless, this compound can be classified as non-toxic considering its effects on seeds and on soil, at least in the medium- to long-term.

PRIMER REPORTE DE Macrophomina pseudophaseolina ASOCIADO A LA PUDRICIÓN DE RAÍZ EN CHILE APAXTLECO NATIVO (Capsicum annuum L.) EN GUERRERO, MÉXICO

<p><strong>Background.</strong> Chili is an important crop for Mexican culture. <strong>Objective. </strong>To identify the pathogen associated with the causal agent of root rot in a native chili pepper Apaxtleco in Guerrero, Mexico. <strong>Methodology.</strong> Root samples of diseased plants were taken from a chili plot in Apaxtla, Guerrero, and were taken to the Phytopathology Laboratory, at Colegio Superior Agropecuario del Estado de Guerrero (CSAEGRO), México. Subsequently, 1 cm root sections were made from healthy and diseased tissue, which were disinfected with 3% sodium hypochlorite for 1 min, and washed three times with sterile distilled water for 1 min, and dried with sterile absorbent paper, later, moistened sterilized paper was placed in the Petri dish and moistened with sterile distilled water and two slides were placed on it arranged in the shape of a cross and at each end of the slides and in the center of these, a piece of previously disinfected root was placed. The plates were kept at 28 °C ± 2 °C for 168 h. The purification of the pathogen was carried out using the hyphal tip and the identification was morpho-molecular. <strong>Results.</strong> The causal agent of root rot in Apaxtleco native chili plants was <em>Macrophomina pseudophaseolina</em>. <strong>Implications.</strong> Our result reveals the opportunity to improve the control of this pathogen at Guerrero, Mexico. <strong>Conclusion.</strong> <em>M. pseudophaseolina</em> causing root rot, in Apaxtleco native chili is reported for the first time.</p>

Effects of a S-metolachlor based herbicide on two plant models: Zea mays L. and Lactuca sativa L

ABSTRACT Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L.

Preparation of porous biochar from fusarium wilt-infected banana straw for remediation of cadmium pollution in water bodies

The problem of cadmium pollution and its control is becoming increasingly severe issue in the world. Banana straw is an abundant bio raw material, but its burning or discarding in field not only causes pollution but also spreads fusarium wilt. The objective of this paper is to utilize biochar derived from the wilt-infected banana straw for remediation of Cd(II) pollution while to eliminate the pathogen. The activity of wilt pathogen in biochar was determined by PDA petri dish test. The Cd(II) adsorption of the biochar was determined by batch adsorption experiments. The effects of KOH concentration (0.25, 0.5 and 0.75 M) on the physicochemical characteristics of the biochar were also observed by BET, SEM, FTIR, XRD and XPS. Results showed that pristine banana straw biochar (PBBC) did not harbor any pathogen. The specific surface area (SSA) and Cd(II) adsorption capacity of 0.75 M KOH modified banana straw biochar (MBBC0.75M) were increased by 247.2% and 46.1% compared to that of PBBC, respectively. Cd(II) adsorption by MBBC0.75M was suitable to be described by the pseudo-second-order kinetic model and Freundlich isotherm. After Cd(II) adsorption, the CdCO3 were confirmed by XRD and observed through SEM. The weakness and shift of oxygen-containing functional groups in MBBC0.75M after Cd(II) adsorption implied that those groups were complexed with Cd(II). The results showed that pyrolysis could not only eliminate banana fusarium wilt, but also prepare porous biochar with the wilt-infected banana straw. The porous biochar possessed the potential to adsorb Cd(II) pollutants.

Phytotoxicity of phenolic compounds of Pistacia vera leaves and its potential use as bioherbicide

In recent years, the intensive and uncontrolled use of synthetic herbicides has resulted in severe soil and water contamination, inducing herbicide resistance and damage to living organisms. The aim of this work was to study the potential bioherbicidal effect of extracts obtained from pistachio leaves. Aqueous extracts (3, 6, 12, and 25%) were prepared and their inhibitory effect on three weed species (Lolium rigidum, Solanum nigrum, and Lactuca serriola) and four crops (maize cv. Celestquatro, barley cv. Yurico, wheat cv. Rimbaud, and lentil cv. Castellana) was studied. Germination bioassays in Petri dishes and in vivo tests on organic and inert substrates were carried out with the extracts. In addition, the phenolic compounds present in the extracts were analysed and germination bioassays of the pure and individual compounds identified were performed. The results showed that the extracts caused a significant suppression of germination in weeds, being more remarkable for broadleaf species. For crops, no adverse effects on germination rates were observed. Inert substrate experiments showed a stronger inhibitory influence on weed germination, whereas organic substrate did not. Autumn leaf extracts showed a higher content of total phenols. Component analysis and bioassay showed that gallic acid, catechin, myricetin, and rutin were identified as individual phenolic compounds in the extracts and demonstrated some allelopathic activity. It may be concluded that pistachio leaf extracts had season-varied allelopathic activity, which is attributed to the combined bioactivity with those individual phenolic compounds.

Delving into Chemical Control Options for Bacterial Canker (Clavibacter michiganensis subsp. michiganensis) in Tomatoes: An In-vitro Study

The 2022/2023 tomato crop witnessed the emergence of Clavibacter michiganensis subsp. michiganensis in a tomato field, leading to symptoms resembling bacterial canker. Identification of the suspected bacterium, C. michiganensis subsp. michiganensis, utilized specific primers (CMM5 and CMM6) for PCR reaction, resulting in a 614 bp fragment. Several fungicides and bactericides were tested for their ability to control bacterial growth in Petri dishes. Fungicides and bactericides that completely inhibit the bacterial growth in Petri dishes included benzalkonium chloride (250 mg a.i./L), copper oxychloride (1680 mg a.i./L with 1000 mg metallic copper/L), copper hydroxide (2764 mg a.i./L with 1800 mg metallic copper/L), fluazinam (500 µL a.i./L), difenoconazole + pidiflumetofen (200 + 120 µL a.i./L), cuprous oxide (1344 mg a.i./L with 1200 mg metallic copper /L), mancozeb + famoxadone (1000 + 100 mg a.i./L), mancozeb (4000 mg a.i./L) and metiram + pyraclostrobin (2200 + 200 mg a.i./L). The packaged dose of casugamycin (60 µL a.i./L) failed to completely inhibit C. michiganensis subsp. michiganensis growth, necessitating doses exceeding 140 µL a.i./L for complete inhibition. Only at a dosage of 140 µL a.i./L was there no observable growth on the Petri dish containing YDC. Label doses of casugamycin did not prevent the growth of any bacteria, albeit partially controlling Clavibacter and Pectobacterium populations. At the dose of 140 µL a.i./L, the sole bacterium that proliferated was Xanthomonas hortorum pv. gardneri. The other bacteria were included in this study focusing on Clavibacter solely to understand the effect of certain products on other important bacteria in tomato cultivation. The active ingredients, difenoconazole + pidiflumetofen (200 + 120 µL/L active ingredient) and fluazinam (500 µL/L active ingredient) effectively suppressed C. michiganensis subsp. michiganensis growth. The study indicates that various tested fungicides and bactericides were effective in curbing C. michiganensis subsp. michiganensis growth under laboratory conditions. Nonetheless, efficacy may fluctuate based on dose and specific product used. Further research, including field trials, is imperative to evaluate product efficacy under real-world conditions and devise comprehensive management strategies for tomato bacterial canker control.

Utilization of Spent Coffee Grounds as a Food By-Product to Produce Edible Films Based on κ-Carrageenan with Biodegradable and Active Properties.

Coffee ranks as the second most consumed beverage globally, and its popularity is associated with the growing accumulation of spent coffee grounds (SCG), a by-product that, if not managed properly, constitutes a serious ecological problem. Analyses of SCG have repeatedly shown that they are a source of substances with antioxidant and antimicrobial properties. In this study, we assessed SCG as a substrate for the production of edible/biodegradable films. The κ-carrageenan was utilized as a base polymer and the emulsified SCG oil as a filler. The oil pressed from a blend of Robusta and Arabica coffee had the best quality and the highest antioxidant properties; therefore, it was used for film production. The film-forming solution was prepared by dissolving κ-carrageenan in distilled water at 50 °C, adding the emulsified SCG oil, and homogenizing. This solution was cast onto Petri dishes and dried at room temperature. Chemical characterization showed that SCG increased the level of polyphenols in the films and the antioxidant properties, according to the CUPRAC assay (CC1 23.90 ± 1.23 µmol/g). SCG performed as a good plasticizer for κ-carrageenan and enhanced the elongation at the break of the films, compared with the control samples. The solubility of all SCG films reached 100%, indicating their biodegradability and edibility. Our results support the application of SCG as an active and easily accessible compound for the food packaging industry.

First Report of Leaf Spot Disease on Lonicera japonica Caused by Nigrospora oryzae in China.

Lonicera japonica Thunb. is a traditional Chinese medicinal plant, which widely cultivated in China, Japan and Korea. From August to October in 2021 and 2022, severe leaf spots symptoms were observed on L. japonica in medicinal botanical garden of Shandong University of Traditional Chinese Medicine (36°55'89"N, 116°79'91"E), Jinan, Shandong Province, China. The disease incidence was above 80% in the 25 acre cultivation area. Early symptoms were small brown spots on the leaves. Then the number of small spots gradually increased and spread over the entire leaves. The small brown spots seldom merge together to form larger lesions. Leaves with typical symptoms were collected from twenty individual plants, and cut into small 5×5 mm fragments in the junction of infected and healthy tissues. The fragments were sterilized in 75% ethanol for 30 s and 1% NaClO for 60 s, rinsed three times in sterile water, and then placed on potato dextrose agar (PDA). After 3 days of incubation at 25°C, fungal plugs along the edge of the colony were cut and transferred to new PDA for purification. A total number of 23 colonies with similar morphological characteristics were obtained, and three representative strains (Lj14, Lj18 and Lj20) were selected for subsequent study. The colonies grew rapidly on PDA and covered the entire petri dish in 4 days. Colonies had abundant aerial hyphae, initially white, round, later turning gray and black. Conidia were oblate or nearly spherical, single-celled, black, and measured in size from 9.6 to 13.2 μm × 7.9 to 16.1 μm in diameter (n=150) (Figure S1). The observed characteristics were close to those of Nigrospora spp. ( Wang et al. 2017). The genomic DNA was extracted, and PCR amplification of the rDNA internal transcribed spacer (ITS), β-tubulin gene (TUB), and translation elongation factor 1-alpha gene (TEF1) were completed by primers ITS1/ITS4, Bt2a/Bt2b and EF1-728F/EF1-986R (Carbone and Kohn, 1999). Sequences were deposited in GenBank (accession nos. OR936661, OR936662, OR936671 for ITS, OR947626, OR947627, OR947628 for TUB, and OR947629, OR947630, OR947631 for TEF1 sequences, respectively). BLAST analyses of ITS (OR936661), TUB(OR947626) and TEF1 (OR947629) sequences exhibited 100% (487 bp out of 487 bp), 99.48% (380 bp out of 382 bp), and 99.6% (248 bp out of 249 bp) similarity to the sequences of N. oryzae strains KoLRI_053384 (MZ855426), LC2991 (KY019496) and LC7307 (KY019409), respectively. Lj14, Lj18 and Lj20 formed a clade with N. oryzae LC6763 and LC2991 in phylogenetic tree (Figure S2). Based on morphological and molecular evidence, the pathogen was identified as N. oryzae (Berk. &Broome) Petch. To fulfill Koch's postulates, the pathogenicity was tested in vivo experiments. Thirty non-wounded healthy leaves of ten intact plants were inoculated with 10 µl spore suspension (106 spores/ml) of three strains, respectively. As negative control, thirty leaves of ten healthy plants were inoculated with sterile water. The inoculated plants were placed at 28°C in the growth chamber with high relative humidity. The pathogenicity tests were repeated three times. Distinct symptoms similar to that of natural conditions were observed on the leaves of inoculated plants after 4 to 7 days. The strain was reisolated from the lesions and identified as N. oryzae by morphological features and ITS sequence. The pathogen has been reported to cause leaf spot disease on tobacco (Wang et al. 2022) and asiatic dayflower (Qiu et al. 2022). To our knowledge, this is the first report of leaf spot caused by N. oryzae on Lonicera japonica in China. The research will be helpful for leaf spot disease control.

First report of Macrophomina phaseolina causing сharcoal rot in soybean (Glycine max (L.) Merr.) plants in Uzbekistan.

The soybean production area is expanding in Uzbekistan. Soybeans were planted on an area of 10 thsd ha and the harvest amounted to 30 thsd metric tons in 2023 (IPAD, https://ipad.fas.usda.gov/countrysummary). Macrophomina phaseolina (Mp) is a soil- and seed-borne fungal pathogen causing economically important diseases of legume crops (Pennerman et al. 2024). Drought stress and a warm climate are favorable to this pathogen (Irulappan et al. 2022). Under these conditions, its microsclerotia survive for a longer period and become more virulent (Chamorro et al. 2015). In August 2022, typical symptoms of charcoal rot were observed in about 25% of "Orzu" soybean cultivar affecting 6 ha located on the experimental base "Durmon" of our institute. Diseased plants displayed the following charcoal rot symptoms: leaves turn yellow, then wilt, die, and remain attached to the plant; the lower portion of the stem and tap root have a light gray or ashy black discoloration; tiny black specks on the lower stem and root; after splitting the stem, it has the appearance of fine charcoal powder. In order to determine the causal agent of these symptoms, a total of 17 diseased plants were collected from focal lesions in soybean plantings. From each plant, twelve sections of stem and root tissue were selected, cut into small 5-mm pieces, and surface sterilized with 1% sodium hypochlorite for four minutes, then rinsed three times with sterile distilled water. The disinfected tissues were dried on sterile filter paper for 5 min and placed on PDA Petri plates, which were incubated in an incubation chamber for 3 days (16 h light (26oC) and 8 h dark (18oC)). Fungi were subsequently subcultured on PDA and incubated for 7 days to obtain pure cultures. Six monohyphal colonies were purified. The colonies showed dense growth, with a gray initial mycelium becoming darker with aging. After 8 days on PDA, black-colored microsclerotia with spherical to oblong shapes were observed. On average, they measured 60 µm in width and 130 µm in length (n = 30). From six isolated monohyphal colonies, one has been chosen for molecular-genetic identification. Molecular-genetic analysis was conducted by amplification and sequencing of the ITS region with the ITS1 and ITS4 primers (White et al. 1990). The resulting sequence was deposited in the NCBI database under accession number OQ073450. After BLAST analysis (Altschul et al. 1990) it was 100% identical with the reference sequences of Mp (accession MT039671, MT039663 and MH496040) isolated in sugar beet, maize and sunflower, respectively, from Serbia. In order to verify the pathogenicity, soybean seedlings (cv. Orzu) were dipped into spore suspension (1 × 107 spores/ml) of sequenced strain R-17 for 1 minute and transferred to a 15 cm diameter plastic pot with 350 g of sterilized soil mix. After 25 days, the inoculated plants showed classic charcoal rot symptoms, while the control plants remained healthy. The pathogen was successfully reisolated from the infected seedlings onto PDA, fulfilling Koch's postulate. The identity of the re-isolated strain was confirmed by morphological features and sequencing of the ITS region. It should be noted that in Uzbekistan, Mp has not been documented in any plants. Therefore, according to our knowledge, this is the first report of this fungus affecting soybean plants in Uzbekistan. Since molecular-genetic analysis of the R-17 strain showed clustering with strains from Serbia, we speculate that there may have been a recent introduction of Mp from Serbia into Uzbekistan. This assumption is additionally confirmed by the fact that Serbia is the largest seed exporter in Uzbekistan. The increase in charcoal rot disease poses a major challenge to soybean production in Uzbekistan. Understanding the genetic diversity of Mp can be utilized to manage this disease, improve soybean yield, and help soybean breeding programs in Uzbekistan.

Quantitative assessment of irrigation water and organic/inorganic amendment on biometric growth profiles of Abelmoschus esculentus and Solanum lycopersicum and their varieties

ABSTRACT In recent decades, the use of chemical fertilizers has been recklessly provoked to meet the increased food needs of the rapidly growing population. However, there is some disagreement about the use of chemical fertilizers in agriculture. Hence, the appropriate nitrogen, phosphate, and potassium ratios must be determined before their application in agricultural practices. This study explored three distinct sources of nutrients to support healthy seed germination and reduce nutrient loss: chemical fertilizers, vermicompost, and nutrient-laden irrigation water supply. A sustainable, affordable, and green petri plate seed germination experiment was used to analyze the biometric growth patterns of two plant species (Abelmoschus esculentus and Solanum lycopersicum). To quantify the effects of different irrigation water sources (groundwater, river water), their combinations with chemical fertilizers and vermicompost (3 ton/ha), multivariate statistical methods such as correlation, principal component analysis, and deep neural networks were used. The purpose of this research was to find the optimal nutrient delivery technique for encouraging healthy plant growth while minimizing the environmental stress of excessive nutrient application.

Mycotic flora characteristics of the endontic flora in patients affected by COVID-19

BACKGROUND: Owing to the fact that, presently, at a dental appointment, it is possible to observe a wide range of consequences arising after COVID-19, among which are observed lesions of the pulp and periodontium of the tooth, additional diagnostic methods should be introduced before choosing treatment tactics. In our previous study, we analyzed the contents of root canals of teeth in patients who had COVID-19 using bacterioscopy. Coccus flora was detected in all cases and elements of Candida yeast-like fungi were recorded in 89 cases (76.1%). Based on the obtained data, it was advantageous to perform microbiological examination of the endodontium in this group of patients to further study their physical and chemical properties and correct the treatment regimen in gangrenous form of chronic pulpitis and aggravated forms of periodontitis, which determined the relevance of the present study. AIM: To reveal the characteristics of the mycotic flora of the endodontium in patients who previously had COVID-19. MATERIALS AND METHODS: A bacteriologic study of root canal contents in patients who had previously undergone a new coronavirus infection at different times, diagnosed as “exacerbation of chronic periodontitis”, “chronic gangrenous pulpitis”, and “acute suppurative periodontitis”, was conducted to detect fungi of the genus Candida in the tooth root canal system, which was obtained during mechanical treatment with a sterile endodontic instrument. The patients (n=49) were divided into groups according to their final diagnosis: group 1, chronic gangrenous pulpitis (27 patients); group 2, acute purulent periodontitis (9 patients); and group 3, exacerbation of chronic periodontitis (13 patients). Then, the collected material was placed in a tube with Amies transport medium and sent to the laboratory. Seeding of the material was performed in sterile Petri dishes on Sabouraud agar by rubbing with a plastic spatula. Further, Petri dishes were placed in the thermostat for 24–48 hours of incubation at 37±10 °C. Then, the study was carried out according to the generally accepted scheme: the obtained cultures were identified to species by the character of growth on dense medium. RESULTS: The given bacteriological study of the patients’ endontic contents confirmed the data of bacterioscopy and concretized the previously obtained results. On final examination, black colonies of Candida albicans were observed in 95.92% of cases. No growth of Candida albicans colonies was observed in two cases (4.08%). CONCLUSION: The bacteriologic study performed after bacterioscopy of diagnosis confirmed the presence of fungi of the genus Candida in the root canals of teeth in patients who previously had COVID-19. The study showed that when treating similar patients, the high risk of infection of periodontal complex tissues by Candida fungi should be considered. It is advisable to supplement the standard protocols of endodontic treatment with physical exposure, for example, laser radiation, or additional medication with antifungal drugs, such as fluconazole.

Retracted] MicroRNA‑320a suppresses tumour cell proliferation and invasion of renal cancer cells by targeting FoxM1.

Subsequently to the publication of the above paper, the authors drew to the attention of the Editorial Office that they made a couple of errors in terms of the data assembly in Figs. 2 and 4 in their paper; specifically, the Transwell assay data shown for the 'miR-320a+/FoxM1+' panel in Fig. 5D on p. 1923 also appeared as the 'ACTN/NC' data panel in Fig. 4E on the same page (Fig. 4E contained the erroneously duplicated panel). In addition, data featured in Fig. 2D of the above paper were strikingly similar to data that appeared in Fig. 6e of the following paper, published subsequently to this article, written by different authors (although a Dr Shiyue Zhao worked in the molecular biology laboratory of Harbin Medical University from 2017 to 2018, and the research collaboration was conducted with Dr Chenlong Li's research group): Li C, Zheng H, Hou W, Bao H, Xiong J, Che W, Gu Y, Sun H and Liang P: Long non-coding RNA linc00645 promotes. TGF-β-induced epithelial-mesenchymal transition by regulating miR-205-3p-ZEB1 axis in glioma. Cell Death Dis 10: 17, 2019. Finally, after having conducted an independent investigation of the data in this paper, the Editorial Office noted that one of the Petri dish images in Fig. 2C was also strikingly similar to data that appeared in Fig. 2H of the abovementioned article in the journal Cell Death & Disease. After having considered the authors' request for corrigendum, in view of the problems that were identified with the data, the Editor of Oncology Reports has decided that, owing to a lack of confidence in the presented data, the paper should instead be retracted from the journal. After having informed the authors of this decision, they accepted the decision to retract this paper. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 40: 1917‑1926, 2018; DOI: 10.3892/or.2018.6597].

Population and Characterization of Rhyzospheric Bacteria of Pineapple Plant (Ananas comosus L. Merr) on The Highland Land of Lumban Sihite Village, Regency Dairi

The rhizosphere is the part of the soil around the roots of plants which is known to have a greater number of rhizosphere bacteria compared to the soil far from the roots. This research aims to determine the population and characteristics of rhizosphere bacteria from pineapple plants (Ananas comosus L. Merr) on the highland land of Lumban Sihite village, Dairi district. The stages used in this research were taking samples at three different points, then carrying out multilevel dilutions, inoculating them into petri dishes filled with PCA (Plate Count Agar) media, then counting the growing colonies using the TPC (total plate count) method, purification, morphological characterization, gram staining and biochemical tests. The research results obtained at point 3 had the largest population of 463.96 x 10⁴ CFU/g, while point 1 had the lowest population, namely 20.07 x 10⁴ CFU/g. Based on the results of morphological, gram staining and biochemical characterization of bacterial isolates, the isolates were identified as belonging to the genus Azospirillum, Bacillus, Pseudomonas and Azotobacter.

Investigation of the Allelopathic Effects of Different Faba Bean (Vicia faba L.) Genotypes Against Various Weeds

Many allelopathic crops are cultivated in agricultural fields, and these plants can influence the growth of other plants in the cultivation environment with their phytotoxic compounds. One of these plants is the faba bean. In this study conducted under the ecological conditions of Sakarya/Arifiye, the allelopathic effects of Eresen-87, Salkim, Bilecik, and Sakarya faba bean genotypes on weeds such as Johnson grass (Sorghum halepense L.), curly dock (Rumex crispus L.), purslane (Portulaca oleracea L.), and wild mustard (Sinapis arvensis L.) were investigated. Weed seeds used in the experiment were collected from agricultural fields in the Sakarya province. Extracts from dried plant parts of faba bean genotypes were prepared and applied to petri dishes containing weed seeds at concentrations of 5% and 10%, with four replications. At the end of the research, it was observed that all faba bean genotypes at all application doses caused a decrease in germination rate (%), root length (cm), and shoot length (cm) parameters in the four weed species tested. The best results were determined as Eresen-87 and Bilecik at 10% concentration. When the activities of fresh and dry extracts of faba bean genotypes was compared, it was determined that dry application had a higher allelopathic effect.