Agar Medium Research Articles

First Report of Xanthomonas hortorum pv. vitians as the Causal Agent of Bacterial Leaf Spot on Lettuce in China.

Lettuce (Lactuca sativa) is a leafy vegetable that belongs to the family Asteraceae. This cool-season crop grows well during Spring and Fall in China (Qi et al., 2021). In October 2023, a leaf disease with dark brown to black lesions was observed on lettuce (var. iceberg) in Yongning Town, Yanqing District, Beijing, China (40°53'N, 116°16'E). The disease incidence ranged from 10 to 40% in the surveyed greenhouse and field. Translucent and water-soaked brown spots were observed on the margins of leaf, then coalesced into large necrotic lesions surrounded by a chlorotic halo. Infected sections were soaked with 75% ethyl alcohol for 7 second, rinsed with sterile water for 15 second twice, and cut into pieces in the sterile water. The sample extracts were streaked on Nutrient agar medium. After incubation for 48 hours, 12 colonies were obtained and all the colonies were Gram-negative and aerobic with yellow, round-shape, smooth and glistening appearance. Four isolates SCZX1-SCZX4 with typical characteristics were selected for further identification tests. Pathogenicity test of SCZX1-SCZX4 was performed on the three-week-old lettuce (var. butterhead) by spraying with the bacterial suspension (108 CFU·ml-1). Inoculated lettuce were incubated at 26℃ and 70% relative humidity in the growth chamber. Another set of lettuce plants were mock inoculated with sterile distilled water. Three trials were carried out per isolate, and each treatment included fifteen lettuce plants. Symptoms appeared within 7-10 days after inoculation and are identical to those naturally infected lettuces. Negative control plants had no symptoms. The 16S rRNA region and two housekeeping genes (gyrB and atpD) of each isolate were amplified with universal primers F27/R1492 (Monciardini et al., 2006) and specific primers (Roach et al., 2018), respectively. According to BLAST analysis of each isolate (Genbank accession number PP027925, PP140779, PP140781 to PP140783, PP137422 to PP137428), BLAST searches of the obtained sequences revealed 100.0% of 16S rRNA region(1400/1400 nucleotides), 100.0% of gyrB(774/774 nucleotides), and 100.0% of atpD(768/768 nucleotides) identity and query coverage to Xhv CFBP 498 (Genbank accession number LR828257.1). Phylogenetic analysis revealed that SCZX1-SCZX4 clustered with the neopathotype strain Xhv LMG 938PT, which was isolated from a diseased L. sativa in Zimbabwe (Timilsina, S et al., 2015). Physiological and biochemical tests of SCZX1-SCZX4 were conducted by the BIOLOG GENIII microplate system (Biolog, Hayward, CA, USA), and the test results are consistent with the Xhv LMG 938PT (Morinière, L et al., 2020) and L1-L7 (Pernezny, K et al., 1995). Strains were re-isolated from re-inoculated lettuce, then re-identified as Xhv by the same method, fulfilling Koch's postulates. Bacterial leaf spot (BLS) is a worldwide-spread lettuce disease caused by numerous bacterial pathogens, including Xhv (Dia, N.C et al., 2022), Pseudomonas cichorii (Patel, N et al., 2021) and P. viridiflava (Alippi, A. M et al., 1999) etc. Xhv had been widely reported as the causal pathogen of BLS in Turkey (Sahin, F et al., 2000), United States (Bull, C.T et al., 2007), Saudi Arabia (Al-Saleh, M et al., 2008), and France (Morinière et al., 2020). However, the first report of Xhv causing BLS on lettuce in China is significant to provide pathogen information for growers in making effective measures to manage this disease.

Membrane-based preparation for mass spectrometry imaging of cultures of bacteria.

The study of the dialogue between microorganisms at the molecular level is becoming essential to understand their relationship (antagonist, neutral, or beneficial interactions) and its impact on the organization of the microbial community. Mass spectrometry imaging (MSI) with matrix-assisted laser desorption/ionization (MALDI) is a technique that reveals the spatial distribution of molecules on a sample surface that may be involved in interactions between organisms. An experimental limitation to perform MALDI MSI is a flat sample surface, which in many cases could not be achieved for bacterial colonies such as filamentous bacteria (e.g., Streptomyces). In addition, sample heterogeneity affects sample dryness and MALDI matrix deposition prior to MSI. To avoid such problems, we introduce an additional step in the sample preparation. A polymeric membrane is interposed between the microorganisms and the agar-based culture medium, allowing the removal of bacterial colonies prior to MSI of the homogeneous culture medium. A proof of concept was evaluated on Streptomyces ambofaciens (a soil bacterium) cultures on solid media. As the mycelium was removed at the same time as the polymeric membrane, the metabolites released into the medium were spatially resolved by MALDI MSI. In addition, extraction of the recovered mycelium from the membrane confirmed the identification of the metabolites by ESI MS/MS analysis. This approach allows both the spatial distribution of metabolites produced by microorganisms in an agar medium to be studied under well-controlled sample preparation and their structure to be elucidated. This capability is illustrated using desferrioxamine E, a siderophore produced by S. ambofaciens.

Unveiling the Substrate-Dependent Dynamics of Mycotoxin Production in Fusarium verticillioides Using an OSMAC-Metabolomics Approach.

Fusarium verticillioides is a prevalent plant pathogenic fungus known to produce harmful mycotoxins, including fumonisins and emerging toxins. This study aimed to investigate the influence of substrate on the temporal patterns of mycotoxin biosynthesis by F. verticillioides, employing a combined OSMAC (One Strain-Many Compounds) strategy and metabolomics approach. The fungus was cultured under various media conditions, and samples were collected over time. LC-MS/MS analyses and a dereplicative workflow were used to profile the secondary metabolite production, focusing on mycotoxins. The results demonstrated that modifying the culture conditions led to significant variations in fungal growth and the nature and relative concentrations of mycotoxins produced. Corn meal agar (CMA) medium was favorable for fumonisins A1 and B1, while malt extract agar (MEA) favored fumonisins A2 and B2. The study also identified the production of other mycotoxins related compounds as fusarins, bikaverin derivatives and fumonisins analogs, under different growth conditions. This study highlights the potential of combining OSMAC and metabolomics to unravel the substrate-dependent and time-dependent variations in mycotoxin biosynthesis by F. verticillioides. The insights gained provide a better understanding of the ecophysiology of this fungus and the occurrence of its mycotoxins, which can inform targeted mitigation strategies to ensure food and feed safety.

Students’ Habits and Identification of Bacteria on Inanimate Surface of Educational Setting

Introduction: Diponegoro Clinic reported 29.1% of students seek infectious diseases treatment. Student habits in the classroom were thought to play roles in the presence of bacteria. Surfaces of inanimate objects in the classroom were potential source for bacteria. The research objectives were analyzing student’s habits and identifying bacteria on the surface of inanimate objects in the classroom. Methods: Four types of samples, including the surfaces of tables, chairs, flips of air conditioners, and floors were taken from 13 faculties at Universitas Diponegoro. Plate count agar media were used to isolate bacterial colonies, and PCR analysis was performed for DNA extraction and amplification. DNA Sanger sequencing techniques were used for genetic bacterial identification. The online questionnaire was used to assess student habits in the classroom. Two hundred students responded. Results and Discussion: Acinetobacter baumannii and Staphylococcus aureus were found in classrooms. These bacteria were associated with respiratory tract infections. This study revealed that 86.5% were between the ages of 17-21, 60.81% were from outside Semarang City, and 88.33% lived in Semarang City. About 60.81% of respondents studied in health sciences. Furthermore, it was reported that 66.67% of respondents were sick in the last few weeks, attended class despite being sick (72.52%), and coughed and sneezed in class (40.99%). Conclusion: Bacteria associated with respiratory tract infection were found. Students' habits in the classroom were potentially caused by the presence of these bacteria. The use of antibacterial agents could reduce the presence of bacteria on inanimate object surfaces.

Cultural and Biochemical Characteristics of Rhizobium Present in Nodule of Pongamia Pinnata (l.) Pierre

The present investigation is an attempt to study the impact of rocky terrain on Rhizobium bacteria of root nodules isolated from legume trees. To study the morphological, cultural, and biochemical characteristics of bacterial strain the bacteria obtained from nodules of selected legume i.e. Pongamia pinnata. Rhizobia inhabited in root nodules of plant, grown in Kota university campus, rhizobia were isolated and inoculated on Yeast Extract Mannitol Agar (YEMA) medium and it’s morphological, cultural and biochemical characteristics were studied. It was observed that colonies were circular or irregular; light creamish, glistering, gelatinous, convex with entire margins. The bacteria were gram negative, rod shaped, aerobic, non-spore forming and slow-moving bacteria arranged single, in pairs and in clusters. It showed negative chemical reaction for indole, while showed positive reaction for citrate utilization, catalase, urease. By the help of bio chemical characteristics it was confirmed that isolated bacterial culture may be of Rhizobium pongamie and rocky terrain with high temperature of environment does not have any negative effect on the characters of Rhizobium, our findings was supported by many earlier investigations.

Virulence and resistance genes in <i>Campylobacter spp</i> isolated from asymptomatic children at Kibera slum in Nairobi, Kenya

BACKGROUND Campylobacter spp. are among the global causes of food poisoning and harbour virulence and resistance genes which play a role in invasion and antibiotic resistance. This study aimed to detect selected resistance and virulence genes in archived Campylobacter spp. isolated from children in Kibera, Nairobi, Kenya. MATERIALS AND METHODS This was a retrospective laboratory-based cross-sectional study on archived samples of Campylobacter spp. at the Department of Public Health, Pharmacology and Toxicology, University of Nairobi. Campylobacter isolates were cultured on modified charcoal cefoperazone deoxycholate agar (mCCDA) media. The presence of selected virulence genes and resistance genes was detected by multiplex polymerase chain reaction (mPCR). STATA13 was used in data analysis. Binary logistic regression was used to ascertain the association between the genes and the Campylobacter spp. RESULTS The Campylobacter spp. under this study were Campylobacter jejuni (C. jejuni) (50%), Campylobacter coli (C. coli) (38%) and Campylobacter lari (C. lari) (12%). The virulence genes detected were cgtB 37 (25%), pldA (20%), cdtA (17%), cdtB (16%), cdtC (6%), wlaN (5%), iam (4%), ciaB (4%) and VirB11 (3%). The virulence gene waaC was not detected in any of the isolates. The resistance genes detected were TetA (42%), Tet B (26%), GyrB (18%) and GyrA (14%). CONCLUSION The study revealed the presence of various virulence and resistance genes in Campylobacter spp. isolated from children. This information could help guide the development and enhancement of guidelines for the management of Campylobacter infections.

Inhibition of the Hyaluronidase Enzyme Produced by Staphylococcus Bacteria Using Vasicine Alkaloids of the Vasica Plant

Hyaluronidase is an enzyme that breaks down primarily hyaluronic acid, thereby disrupting the structural integrity of the extracellular matrix (ECM) found in connective tissues, which is considered a virulence factor. The aim of this research was to study the effect of a plant-active compound (vasicine) that was separated from a plant sample as an inhibitor agent for the hyaluronidase enzyme that was isolated from Staphylococcus aureus, which is considered a virulence factor. 120 samples were randomly isolated from infected burns. The isolates showing highly hydrolyzed zones were identified. Cell growth as well as hyaluronidase activity are measured spectrophotometrically by the turbidity reduction assay. The results showed that 100 out of 120 clinical samples grew bacteria when cultured on blood agar medium. Also, it was found that of the 100 isolates, 56 (56%) belonged to S. aureus and had an inhibitory zone of hyaluronidase of 5–26 mm, and the inhibitory zone was increasing over time.

Antibacterial potential of queen pineapple (Ananas comosus (L.) Merr Var. Queen) peel extract on the growth of Lactobacillus acidophilus bacteria

Based on the Global Burden of Disease Study in 2017, the prevalence of caries in each country reached 20% to more than 50%. Caries is formed due to the role of several factors including host, agent (microorganisms), substrate, and time. Bacteria involved in the origin of caries formation such as Lactobacillus group bacteria found in the oral cavity which can cause dental caries, one of which is Lactobacillus acidophilus. The use of natural cleansers is highly recommended to remove residual bacteria as an effort to prevent caries. Queen Pineapple (Ananas comosus (L.) Merr Var. Queen) is a fruit that contains very complex compounds that can act as anticarcinogenic and antibacterial. This study aims to determine the Minimum Bactericidal Concentration (MBC) and Minimum Inhibitory Concentration (MIC) against the growth of Lactobacillus acidophilus bacteria. This type of research was a laboratory experimental type with posttest only control group design. This study used the dilution method of the number of samples, namely concentrations of 0.781%, 1.56%, 3.125%, 6.25%, 12.5%, 25%, 50%, 100%, positive controls and negative controls. This study was conducted 3 times repetition. Manual calculation of the number of bacterial colonies that grow on nutrient agar media and expressed in colony forming units (CFU) which will determine the MBC and MIC. The Shapiro-Wilk test showed a p value> 0.05 at all concentrations and normally distributed data, but when tested for homogeneity the data was not homogeneous so that the non-parametric statistical test continued using the Kruskal Wallis test showing a value of p < 0.05. Conclusion: Colony count results showed that the concentration of 3.12% can inhibit the visible growth of Lactobacillus acidophilus bacteria which is stated as the Minimum Inhibitory Concentration (MIC) and can prevent growth after subculture to antibiotic-free medium at a concentration of 6.25% which is stated as the Minimum Bactericidal Concentration (MBC).

Molecular Diagnosis of Vaginal Microbiota Associated with Spontaneous Abortion in Women

Spontaneous abortion (SA) is a sever disease in which a women losses her foetus usually before 24 weeks of the pregnancy. About 10% -50% of pregnancy cases are run out with SA for reasons related with women's age and health. This condition occurrence may increases if the patient has a history of bacterial vaginosis. This study aimed at the characterization and isolation of vaginal microbiota generally and highlight on commensal bacteria becoming opportunistic when circumstances are favourable. From October to December 2022, about 100 samples were collected, 50 specimens from women with SA and 50 specimens from healthy pregnant outcomes (control). The high vaginal swabs samples were collected from Babylon Teaching Hospital for Maternity and Children and Imam Sadiq Teaching Hospital in Babylon, Iraq. To culture the samples, they were transported by media swab to laboratory. The culture of bacteria was done on 4 types of agar media: UTI chromogenic agar, MRS agar, MacConkey agar and blood agar. The first identification of bacteria was based on phenotypic traits of colonies, using manual biochemical tests and gram stain. Finally, the diagnosis was confirmed genetically by extracting bacterial genomic DNA for 20 of bacterial isolates under study and using PCR technique for 16S rRNA Loci gene and sequencing. The current study results showed difference in bacterial genera in women with SA compared with healthy women. It was also noted that embroilment of Enterococcus faecalis occurred in most cases of SA with an estimated percentage of 56% (28/50), thus defeating Escherichia coli by 32% (16/50) and 4% (2/50) for Klebsiella pneumonia and 4% (2/50) for Enterococcus gallinarum. In this study, some very rare bacteria species were identified including Acinetobacter junii at 2% (1/50) and Corynebacterium coyleae at 2% (1/50). While the percentage of bacteria associated with healthy women was: 30% (15/50) for E. faecalis, 26% (13/50) for E. coli, 18% (9/50) for K. pneumonia, 24% (12/50) for Staphylococcus epidermidis, and 2% (1/50) for Metabacillus niabensis (which was diagnosed for the first time in Iraq as well as the rest of the world in a clinical sample).

A novel alkali and thermotolerant protease from Aeromonas spp. retrieved from wastewater

Enzymes are integral to numerous industrial processes, with a growing global demand for various enzyme types. Protease enzymes, in particular, have proven to be cost-effective, stable, and compatible alternatives to traditional chemical processes in both industrial and environmental applications. In this study, an alkaline protease-producing strain of Aeromonas spp. was isolated from a wastewater treatment plant in Iran. The protease production was confirmed by culturing the strain on casein agar medium. The bacterium was identified through morphological, biochemical, and 16 S rRNA sequencing analyses. The optimal culture medium for bacterial growth and enzyme production was obtained using peptone, salt, yeast extract, galactose, and CaCl₂ at an initial pH of 8. Maximum protease production was achieved after 20 h of incubation at 40 °C. To partially purify the enzyme, the supernatant of the bacterial culture medium was first centrifuged, and the enzyme was precipitated using ammonium sulfate, followed by dialysis. Zymography revealed the production of one type of protease during bacterial growth. The partially purified protease exhibited optimal activity at pH 8.5 and maximum stability at pH 9. The optimum temperature for maximum enzyme activity was observed at 50 °C, with 100% residual activity retained for 1 h at 0 °C. The effect of metal ions on enzyme activity was assessed, revealing that KCl induced the most significant effects (p < 0.0001) on enzyme activity. Chemical amino acid modifiers and inhibitors, such as EDTA, DEPSI, and IAA, did not exhibit significant inhibition. In contrast, PMSF and HNBB significantly (p < 0.0001) reduced enzyme activity, suggesting that the enzyme could be classified as a serine protease. The protease also demonstrated high stability in the presence of 2% SDS, showing no signs inactivation. The alkaline pH optimum, thermal stability, and resistance to SDS exhibited by the protease produced by the Aeromonas strain are particularly promising characteristics that warrant further investigation. Based on preliminary tests and the enzyme’s characteristics, this protease can be recommended for various applications, pending further studies.

A Molecular Approach to Understand the Involvement of Mycoplasma in Suppurative Otitis Cases of Cattle in Chittoor District of Andhra Pradesh

In bovines the economic losses mainly due to the outbreak of diseases, leads to mortality, morbidity, treatment cost and reduced production. Recently in August month of 2024, received 13 bovine suppurativeotitis samples from outbreak in KuppamMandal of Chittoor district. The history having the purulent discharges with foul smell from ear infections of cattle that to crossbreed cattle of all age groups are affected. After 5 days of appearing aural discharges the animals were also shown the nervous signs, head tilting and other clinical findings includes unilateral or bilateral ear droop, epiphora, ptosis, abnormal nystagmus, strabismus, regurgitation, stiff neck, opisthotonus, facial hyperesthesia, purulent aural discharge, nasopharyngeal collapse, recumbency and finally death were noticed in severely affected animals. All the samples were processed for cultural tests by inoculating in PPLO selective broth and selective media PPLO agar then incubated anaerobically at 370C and observed the color development in broth pink to yellow color after 3- 5 days of incubation indicative of positive growth and fried egg micro colonies on selective PPLO agar media after 8-14 days of incubation observed under low power and 40X. The DNA was isolated from all the samples and screened for presence of Mycoplasma by targeting 16s rRNA gene and found that out of 13 samples 10 were positive for genus Mycoplasma and produced the predicted 280bp size product in all positive samples. The suppurativeotitis in cattle usually is caused by Actinomyces spp., Corynebacterium pseudotuberculosis, E. coli, Heamophilus, P.multocida, Pseudomonas spp, Streptococcus spp., and Mycoplasma bovis. This study was targeted only the emerging pathogen i.e the cellwall deficient bacteria Mycoplasma because of infections is hampered by a lack of effective vaccines and specific treatments, leads to increasing trends in antimicrobial resistance. Concluded that isolation and identification of the pathogenic ........

Characterization of alkaline protease enzyme produced from marine yeast Candida orthopsilosis AKB-1 and its applications.

The present study has undertaken the isolation of marine yeasts from mangrove sediment samples and their ability to produce alkaline protease enzymes. A total of 14 yeast isolates were recovered on yeast-malt agar (YMA) and yeast extract peptone dextrose (YEPD) agar medium. After screening for proteolytic activity on skim milk agar, marine yeast isolate, AKB-1 exhibited a hydrolysis zone of 18mm. Optimal conditions for the enzyme production from yeast isolate AKB-1 were at 30°C, pH 8, fructose as carbon source, potassium nitrate as nitrogen source, and 25% saline concentration. Under the optimal conditions, the protease enzyme activity of the isolate AKB-1 was observed to be 978IU/mL. The structural and functional analysis was carried out through FTIR and HPLC analysis for the extracted protease enzyme. Furthermore, the enzyme produced was partially purified by solvent extraction using ethyl acetate and ammonium sulfate precipitation (3.4-fold) followed by dialysis (56.8-fold). The molecular weight of the purified enzyme was observed to be around 60kDa using SDS-PAGE. The extracted protein showed good antibacterial activity against six different clinical bacterial pathogens and the highest against Bacillus cereus (16 ± 0.5mm). The extracted protease enzyme was revealed to remove blood stains from cloth within 20min of application similar to the commercial detergent. The marine yeast isolate was further identified as Candida orthopsilosis AKB-1 (Accession number KY348766) through 18S rRNA sequencing, and a phylogenetic tree was generated.

Isavuconazole and Amphotericin B Synergic Antifungal Activity: In Vitro Evaluation on Pulmonary Aspergillosis Molds Isolates

Background/Objectives. Pulmonary aspergillosis is a severe respiratory infection caused by Aspergillus spp., whose resistance profiles and invasive attitude complicate therapeutical strategies. Several aspergillosis cases emerged as superinfections during the SARS-CoV-2 pandemic when isavuconazole and amphotericin B became essential antifungal alternatives. The main purpose of the present study was to investigate a possible synergic activity between these molecules against Aspergillus spp. isolated from respiratory samples. Methods. The gradient test method detected isavuconazole and amphotericin B MIC values, prompting an arrangement of their combination into an R.P.M.I. agar medium. According to Liofilchem s.r.l. instructions, the FIC index was used to establish synergy, additivity, indifference, or antagonism. Results. Among 36 Aspergillus spp. isolates, only A. fumigatus strains showed both synergy and additivity episodes. A. niger reported the highest antagonism percentage, while A. terreus revealed several indifference episodes. Conclusions. Isavuconazole and amphotericin B remain fundamental therapeutical alternatives, including a possible synergic effect against A. fumigatus. On the basis of this species-related difference, further studies will be essential to investigate different antifungal drug combinations against filamentous fungi isolates.

Paracoccus actinidiae sp.nov., a novel bacterium isolated from kiwi tree rhizosphere soil.

Strain M09T was isolated from the rhizoshere of kiwi fruit trees from an orchard located in Fangshan, Beijing, PR China (39° 49' 25.1″ N, 116° 4' 44.5″ E,). It is a short rod-shaped, Gram-stain-negative, facultatively anaerobic bacterium that tests positive for both oxidase and catalase. The strain exhibited growth within the temperature range of 15-45 °C (optimal growth at 30 °C) and the pH range of 4.0-10.0 (optimal growth at pH 7.0) and without NaCl. It also grew in a sodium chloride-free nutrient agar (NA) medium. The results of phylogenetic analysis of the 16S rRNA gene sequences indicated that M09T represents a member of the genus Paracoccus and shares high similarity with Paracoccus everestensis S8-55T (98.46%) and Paracoccus aerius 011410T (97.58%). The average nucleotide identity values between M09T and P. everestensis S8-55T, P. aerius 011410T, Paracoccus marinaquae X HP0099T and Paracoccus fontiphilus MVW-1T were 95.56, 84.51, 79.83 and 83.68%, respectively. The digital DNA-DNA hybridisation values between between M09T and P. everestensis S8-55T, P. aerius 011410T, P. marinaquae X HP0099T and P. fontiphilus MVW-1T were 56.40, 29.30, 21.60 and 28.60%, respectively. The major fatty acids identified were C10 : 0 3-OH (51.8%) and C18 : 1ω7c (35.5%). The major respiratory quinone was Q-10, with Q-8 present as a minor component. Polar lipids were mainly comprised of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), and phosphatidylethanolamine (PE). Genome sequencing revealed that the strain has a DNA G+C content of 64.31 mol%. On the basis of this comprehensive taxonomic characterisation data, M09T represents a novel species within the genus Paracoccus and has been named Paracoccus actinidiae sp. nov. The type strain is designated as M09T (=GDMCC 1.4157T=KCTC 8143T).

Evaluation of Geh gene expression in Staphylococcus aureus isolated from acne patients

Acne vulgaris is a chronic skin disease that affects the hair follicle and sebaceous glands. Staphylococcus aureus colonizes human skin and causes infections ranging from local skin infections to systemic infections that may threaten human life due to its ability to produce many virulence factors and antibiotic resistance. The objective of this study is to measure the genetic expression of Geh gene responsible for producing the lipase enzyme from S. aureus isolated from acne patients. This study was conducted by collecting 130 swabs from acne patients at Tikrit Teaching Hospital. Using routine bacterial isolation and identification methods, 50 samples (38.4%) of the total samples were identified as S. aureus through its ability to grow in mannitol salt agar medium, the fermentation of mannitol sugar, and the change of the medium color to yellow. The Geh gene expression of ten S. aureus isolates from acne patients was examined using RT-PCR. The results showed that Geh gene was expressed in all isolates, with an expression ranging from 1.5 to 7.2, and that the mean folding of the Geh gene for ten samples was 4.2. This indicates the presence of high gene expression of the Geh gene in S. aureus isolates. Therefore, it is concluded that Lipase enzyme plays an important role in the pathogenesis of S. aureus in acne patients.

First report of potato pink rot caused by Phytophthora erythroseptica in Colorado.

Pink rot, caused by the oomycete Phytophthora erythroseptica, is a serious disease that may cause substantial losses to potato growers. In 2023, high infection rates of pink rot were noticed in the San Luis Valley (SLV), Colorado around harvest time and in storage with several growers losing complete storage pins to pink rot. In September 2023, tubers with pink rot symptoms were collected from two grower fields of Russet Norkotah (~2-3% infection) and Canela Russet (~5% infection) near the San Luis Valley Research Center at harvest time. Infected tubers showed dark discoloration on the surface at the stem end. Upon cutting, affected tissue developed salmon pink color about 20-30 min later (Fig. 1). DNA was extracted from two symptomatic tubers from each cultivar and healthy tubers using DNeasy PowerSoil Pro Kit (Qiagen, MD, USA) according to the manufacturer's instructions. The conventional PCR and qPCR assays developed by Cullen et al. (2007) were used to detect P. erythroseptica. In the conventional PCR, the primer pair Pery2F1/R1 produced expected bands of 135bp from symptomatic tubers but not from the healthy tubers. The symptomatic tubers were positive in the qPCR using the primer-probe set 99F, 177R, and 133T (Cullen et al., 2007). P. erythroseptica was isolated by culturing specimens of infected tissues on PARP selective media (Jeffers and Martin, 1986). A week later colonies of white color grew on the media. These colonies were confirmed to be of P. erythroseptica by PCR as mentioned above. The colonies of two isolates were transferred to water agar media, then three days later a mycelium tip was excised and cultured on PDA media for single isolation. On PDA media the colonies showed chrysanthemum pattern. Four days later DNA was extracted from the two isolates, RN296-1 and Canela-2, and tested positive for P. erythroseptica by the above-mentioned PCR. PDA agar plugs of two isolates were used to inoculate surface sterilized potato tubers. The isolate SLV-2023-Canela2 was inoculated on tubers of Russet Norkotah and Reveille Russet, 10 each, while10 tubers of Russet Norkotah were inoculated with the isolate SLV-2023-RN296-1. Ten tubers of Russet Norkotah were inoculated by sterilized plugs of PDA for negative controls. Tubers were left at room temperature for a week. All tubers of Russet Norkotah inoculated with SLV-2023-Canela2 and RN296-4 developed pink rot symptoms and tested positive for P. erythroseptica by PCR, while only 9 tubers of Reveille Russet inoculated with SLV-2023-Canela2 developed symptoms and were positive to P. erythroseptica by PCR. No symptoms were observed on the mock inoculated tubers and no P. erythroseptica was detected by the PCR. P. erythroseptica was isolated again from Russet Norkotah tubers inoculated with RN296-1 on PDA media and tested positive for P. erythroseptica by PCR one week later. To further confirm the identity, the ITS region was amplified using the primers ITS-1 and ITS-4 (White et al., 1990) from DNA extracted from inoculated Russet Norkotah tubers with SLV-2023-Canela2 isolate. PCR product was purified using QIAquick Gel Extraction Kit (Qiagen, MD, USA)and cloned using TOPO TA Cloning Kit for Sequencing (Invitrogen, MD, USA). Four clones were submitted for sequencing. The 846 nt sequence of the ITS was submitted to the GenBank (accession number PP587391) shared 99.76% identity with the P. erythroseptica strain BBA 62683 (KJ755119). P. erythroseptica was identified previously using morphological tools from tubers with symptoms resembling pink rot collected in the SLV (Tyler et al., 2002). However, in that report neither Koch's Postulates, nor molecular identification were conducted, hence, the current study presents the first molecular report of pink rot in the SLV, Colorado. Rapidly changing climate and increased temperature around harvest time may lead to an increase in the incidence of pink rot, hence effective management strategies need to be developed and implemented.

Control of fungal diseases of tomato (&lt;i&gt;Lycopersicum esculentum&lt;/i&gt; Mill) fruits using various plant extracts

Plant harmful fungi induce symptoms of illnesses that significantly impair the quantity and quality of tomato (Lycopersicum esculentum) yields. The high-water composition of tomatoes renders it highly vulnerable to fungal decay. These fungi, responsible for the decay of tomatoes, generate mycotoxins that pose serious risks to human health. Thus, this research goal is to separate, characterize, and classify the fungi linked with the decline of tomato produce sold across four markets in Mkpat Enin and Ikot Abasi Local Government Areas of Akwa Ibom State, Nigeria. Among the fungal pathogens extracted from afflicted tomato fruits were Fusarium moniliformes, Rhizopus stolonifera, and Aspergillus alternata. Different concentrations of the extracts were individually introduced into Potato Dextrose Agar media. The fungal pathogens were at that point individually introduced into the media and left to incubate for 7 days. Findings revealed that P &lt; 0.05 suppressed the mycelial evolution of the fungal pathogens at a greater concentration tested, with the extent of inhibition varying among different extracts. The results concerning the proportion inhibition of plant extracts on different fungus indicated that, at concentrations ranging from 40% to 80%, ethanolic extracts derived from Cola acuminata and Zingiber officinale significantly (p&lt;0.05) restrained the growth of F. moniliformes, R. stolonifera, and A. alternata. Specifically, the ethanolic leaf extract of C. acuminata demonstrated moderate inhibition on A. alternata at 60%, while the ethanolic extract of Zingiber officinale exhibited low inhibition on F. moniliformes at 40%. At a concentration of 60% in ethanolic extracts, F. moniliformes experienced the greatest inhibition among the plant extracts, whereas A. alternata displayed the least inhibition. Pathogenicity testing indicated that Aspergillus alternata exhibited the largest decay of 25mm in diameter in a healthy tomato fruit, while Rhizopus stolonifera had the smallest decay diameter. Thus, to cover the ledge life of tomato fruits, therefore there’s adequate need to implement proper handling techniques and utilize adequate storage facilities.

Understanding rhizospheric microbial dynamics in gladiolus corms through quorum sensing and quorum quenching for disease control and growth promotion

Gladiolus, a widely cultivated cut flower known for its aesthetically pleasing multicoloured spikes, has earned significant commercial popularity. A comprehensive understanding of the rhizosphere bacterial community associated with gladiolus is imperative for revealing its potential benefits. Molecular characterization is considered an effective method to gain insights into the structural and functional aspects of microbial populations. The soil characteristics and bacterial communities in the rhizosphere are typically influenced by quorum sensing (QS) and quorum quenching (QQ) mechanisms. This study aims to explore the niceties and diversity of rhizospheric bacterial populations linked with gladiolus corms, with a specific focus on understanding the dynamics of QS and QQ mechanisms in their complex interactions. The isolation of bacterial strains was achieved through the serial dilution method on nutrient agar (NA) media. The identification of the isolates was accomplished by amplifying 16 S rRNA gene sequences via polymerase chain reaction (PCR) via the use of universal primers. Sequence analysis was conducted via BLAST on the National Center for Biotechnology Information (NCBI) database. The characteristics of the isolated bacteria were elucidated via biosensors. This study identified three QS strains and five QQ strains. A consortium of quenchers was formulated utilizing five strains that demonstrated efficacy in mitigating the impact of disease on gladiolus and fostering growth. Among the three treatments—Scale, Descale, and Descale and Cut Half (DSC)—the DSC treatment emerged as the most effective. This treatment exhibited a broader range of variation in biological parameters over time, aligning with prevailing trends in the local market.

Comparative Analysis of Some Morpho-cultural Characters of Venturia inaequalis (Apple Scab Pathogen) under Kashmir Conditions

Apple (Malus × domestica Borkh.) represents one of the most widely cultivated and economically important temperate fruit crops in the world. However, its cultivation faces significant challenges due to various fungal pathogens, particularly apple scab inflicted by Venturia inaequalis, which has a profound impact on the yield and quality of apple, resulting in substantial economic loss. The pervasive nature of V. inaequalis and its ability to damage crops poses a serious threat to sustainable apple production. In this study, the morpho-cultural characteristics of V. inaequalis were systematically analyzed and compared between the Shopian and Baramullah districts of the Kashmir Valley. Ten isolates from each district were grown on Malt Extract Agar (MEA) and Potato Dextrose Agar (PDA) for comparative analysis. The colonies were characterized by a compact hue ranging from greyish-green to blackish and exhibited a densely velvety texture. Mycelial growth was predominantly aerial, with some isolates displaying partial irregularity in colony margins, while others exhibited greater uniformity. The mean colony radii for potato dextrose agar and malt extract agar media was measured as 23.01 mm and 28.50 mm for the Shopian district, and 28.09 mm and 33.33 mm for the Baramullah district, respectively. The mean conidial spore density was recorded at 27.87 spores/cm² for the Baramullah district and 34.67 spores/cm² for the district Shopian, respectively. This variation could be attributed to several factors, including genetic diversity within the pathogen populations, differences in altitude, climate, and other environmental factors, the selection pressure exerted by fungicide applications, the emergence of novel pathogen races, and phenotypic plasticity driven by the differing agricultural practices and microclimatic conditions in the respective regions.

Pathogenicity of Bacillus subtilis Against Symbiotic Fungus of Euwallacea fornicates (Coleoptera: Scolytidae) From South India.

In India, the shot-hole borer, Euwallacea fornicates, commonly known as the tea borer, infests the galleries of tea plant twigs under natural conditions and is a major pest of tea. The current investigation focuses on the antagonistic ability of Bacillus subtilis to directly inhibit the growth of plant pathogens in two different climatic regions of tea-growing area. The evaluation reveals that (a) B. subtilis can directly suppress the growth of plant pathogens (b) in the in vitro evaluation; the B. subtilis suppressed the growth of the Fusarium ambrossium, which is the nourishment for the ambrosia beetle, (c) it also revealed that the antagonistic microbes and the entomopathogens are able to control the pest population of the shot hole borer of tea. The impact of B. subtilis on mycelial growth, sporulation, and spore germination of F. ambrosium in agar medium was observed. In the field condition on the post-treatment assessments shows an average decline of 40% in both foliar and soil drenching. Hence, we recommend the antagonistic bacterium B. subtilis for including as an IPM for the management of shot hole borer in tea.