Identifying susceptible groundwater contamination zones in western Odisha of India using hydro-geochemical and geospatial approaches.

Nuapada is one of the most drought-affected and fluoride-contaminated districts in Odisha, India. The presence of various dissolved substances, evapotranspiration, and lowering water table during pre- and post-monsoon (PRM and POM) seasons are responsible for declining groundwater (GW) quality over the Nuapada region. To comprehend the contaminated GW zones over the Nuapada and Komna blocks of the northern Nuapada district during the seasons, integration of hydrogeochemistry and statistical approaches using GW sample data on a geospatial platform have been done. The analysis exhibits that the major source of groundwater contamination is mostly geogenic with little anthropogenic impact. The cumulative impact of fluoride (F-), iron (Fe2+), and nitrate (NO3-) contents are noticed in great-depth zones of the water table in the north and south parts of Nuapada and Komna blocks, respectively. The dominant hydro facies, such as Na-Cl (41.77%) and Ca-Cl (25.31%) types exist over both blocks during PRM and POM seasons, respectively. Demarcation of contaminant and susceptible zones over the study area using geospatial analysis and groundwater quality indices (GWQI) were done. About 3% of the total area, in the north and middle parts of the Nuapada and Komna blocks, falls under contamination zones and is unfit for drinking purposes, and about 35% of the region is susceptible to future contamination. The outcome of the result analysis will enhance the scope for researchers, policymakers, and water managers to regulate emerging health, agricultural, and industrial issues in the stressed aquifer system in India and the world.

Colonization potential of endophytes from halophytic plants growing in the "Runn of Kutch" salt marshes and their contribution to mitigating salt stress in tomato cultivation.

Increasing soil salinity depreciates the quantity of the crop produce. Looking at the tremendous potential of plant-associated microorganisms in salinity stress mitigation, it would be very useful in exploring and deciphering salt-tolerant microorganisms from halophytic plants and their utilization in cultivated plants. With this aim, in the present study, four halophytic plants were taken from Rann of Kutch, and bacterial endophytes were isolated from different plant organs. These endophytes were characterized by plant growth and health promotion features. The molecular identification was done based on 16 s rRNA sequence similarity. It was found that the endophytic bacteria isolated from 4 different halophytes found sharing phylogenetic relatedness. Four potential endophytes Alkalihalobacillus gibsonii 2H2, Achromobacter insuavis 2H18, Terribacillus halophilus 2H20, and Bacillus siamensis 4H1 were tested in tomato for salinity stress alleviation. Changes in the levels of antioxidants were analyzed. Total chlorophyll, total phenolics, malondialdehyde, and proline content indicated reduced damage in the plant system due to salinity by the application of endophytes. All the treatments exhibited low levels of electrolyte leakage. The accumulation of enzymatic reactive oxygen species scavengers was assessed from the levels of peroxidase, catalase, superoxide dismutase, phenylalanine ammonia-lyase, ascorbate peroxidase, and guiacol peroxidase. The NBT and DAB staining confirmed the findings. The reduction in the accumulation of Na+ ions in tomato leaves was visualized using Sodium Green probes under CSLM and found to be lowest in Terribacillus halophilus 2H20 and Bacillus siamensis 4H1 inoculated plants. The endophyte Terribacillus halophilus 2H20 was the most promising isolate. The colonization in tomato roots was confirmed using a cell tracker system. Results showed that the endophytes were found to have salinity stress mitigation traits. The efficiency could be further improved with the combination of other endophytes tested earlier.

Isolation and characterization of halotolerant plant growth promoting rhizobacteria from mangrove region of Sundarbans, India for enhanced crop productivity.

Halotolerant plant growth promoting rhizobacteria (PGPR) are beneficial microorganisms utilized to mitigate the biotic and abiotic stresses in plants. The areas of Sundarban mangroves of West Bengal, India have been reported to be rich in halotolerant microflora, yet major area remains unexplored. The present study, therefore, aims to map down the region-specific native microbial community potent of salt tolerance, plant growth promoting (PGP) activity and antagonistic activity against fungal pathogens. Bacterial samples were isolated from the saline soil of the Sundarban mangroves. A total of 156 bacterial samples were isolated and 20 were screened for their salt tolerance potential. These isolates were characterised using morphological, biochemical, and molecular approaches. Based on 16s rRNA sequencing, they were classified into 4 different genera, including Arthrobacter sp. (01 isolate), Pseudomonas plecoglossicida (01 isolate), Kocuria rosea (01 isolate), and Bacillus (17 isolates). The halotolerant isolates which possessed plant growth promoting traits including phosphate, and zinc solubilization, indole acetic acid production, siderophore, and ammonia generation were selected. Further, the effect of two halotolerant isolates GN-5 and JR-12 which showed most prominent PGP activities was evaluated in pea plant under high salinity conditions. The isolates improved survival by promoting germination (36 to 43%) and root-shoot growth and weight of pea plant in comparison to non-inoculated control plants. In a subsequent dual culture confrontation experiment, both these halo-tolerant isolates showed antagonistic activities against the aggressive root rot disease-causing Macrophomina phaseolina (Tassi) Goid NAIMCC-F-02902. The identified isolates could be used as potential bioagents for saline soils, with potential antagonistic effect on root rot disease. However, further studies at the physiological and molecular level would help to delineate a detail mechanistic understanding of broad-spectrum defence against salinity and potential biotic pathogen.

Virulence and pathogenicity determinants in whole genome sequence of Fusarium udum causing wilt of pigeon pea.

The present study deals with whole genome analysis of Fusarium udum, a wilt causing pathogen of pigeon pea. The de novo assembly identified a total of 16,179 protein-coding genes, of which 11,892 genes (73.50%) were annotated using BlastP and 8,928 genes (55.18%) from KOG annotation. In addition, 5,134 unique InterPro domains were detected in the annotated genes. Apart from this, we also analyzed genome sequence for key pathogenic genes involved in virulence, and identified 1,060 genes (6.55%) as virulence genes as per the PHI-BASE database. The secretome profiling of these virulence genes indicated the presence of 1,439 secretory proteins. Of those, an annotation of 506 predicted secretory proteins through CAZyme database indicated maximum abundance of Glycosyl hydrolase (GH, 45%) family proteins followed by auxiliary activity (AA) family proteins. Interestingly, the presence of effectors for cell wall degradation, pectin degradation, and host cell death was found. The genome comprised approximately 895,132 bp of repetitive elements, which includes 128 long terminal repeats (LTRs), and 4,921 simple sequence repeats (SSRs) of 80,875 bp length. The comparative mining of effector genes among different Fusarium species revealed five common and two specific effectors in F. udum that are related to host cell death. Furthermore, wet lab experiment validated the presence of effector genes like SIX (for Secreted in Xylem). We conclude that deciphering the whole genome of F. udum would be instrumental in understanding evolution, virulence determinants, host-pathogen interaction, possible control strategies, ecological behavior, and many other complexities of the pathogen.

Salinity Alleviation and Reduction in Oxidative Stress by Endophytic and Rhizospheric Microbes in Two Rice Cultivars.

Increased soil salinity poses serious limitations in crop yield and quality; thus, an attempt was made to explore microbial agents to mitigate the ill effects of salinity in rice. The hypothesis was mapping of microbial induction of stress tolerance in rice. Since the rhizosphere and endosphere are two different functional niches directly affected by salinity, it could be very crucial to evaluate them for salinity alleviation. In this experiment, endophytic and rhizospheric microbes were tested for differences in salinity stress alleviation traits in two rice cultivars, CO51 and PB1. Two endophytic bacteria, Bacillus haynesii 2P2 and Bacillus safensis BTL5, were tested with two rhizospheric bacteria, Brevibacterium frigoritolerans W19 and Pseudomonas fluorescens 1001, under elevated salinity (200 mM NaCl) along with Trichoderma viride as an inoculated check. The pot study indicated towards the presence of variable salinity mitigation mechanisms among these strains. Improvement in the photosynthetic machinery was also recorded. These inoculants were evaluated for the induction of antioxidant enzymes viz. CAT, SOD, PO, PPO, APX, and PAL activity along with the effect on proline levels. Modulation of the expression of salt stress responsive genes OsPIP1, MnSOD1, cAPXa, CATa, SERF, and DHN was assessed. Root architecture parameters viz. cumulative length of total root, projection area, average diameter, surface area, root volume, fractal dimension, number of tips, and forks were studied. Confocal scanning laser microscopy indicated accumulation of Na+ in leaves using cell impermeant Sodium Green™, Tetra (Tetramethylammonium) Salt. It was found that each of these parameters were induced differentially by endophytic bacteria, rhizospheric bacteria, and fungus, indicating different paths to complement one ultimate plant function. The biomass accumulation and number of effective tillers were highest in T4 (Bacillus haynesii 2P2) plants in both cultivars and showed the possibility of cultivar specific consortium. These strains and their mechanisms could form the basis for further evaluating microbial strains for climate-resilient agriculture.

The Psychological Impact of Rhino-Orbital Mucormycosis During the Second Wave of COVID-19 Pandemic From South East Asian Country.

AIM: The present study addressed overcoming the lacunae in the literature of psychiatric manifestations associated with rhino-orbital mucormycosis. The current study aimed to assess the symptoms of depression, anxiety, stress, coping measures, suicidal intent, and visual disability in patients of rhino-orbital mucormycosis (ROM) during the epidemic of the disease at the nodal tertiary care center in North India. METHODS: Fifty-four inpatients of laboratory-proven rhino-orbital mucor-mycosis (ROM) were included for an observational, cross-sectional study at nodal, designated COVID-19, and mucormycosis treating tertiary care hospital. Patients with Hindi Mini-Mental State Examination score <24, prior psychiatric illness, and severely ill requiring ventilator support were excluded. The psychological variables were assessed using Depression, Anxiety, and Stress Scale 21 (DASS 21), Beck's Suicide intent Scale, Coping Scale Questionnaire, and Visual disability scale (IND-VFQ33). Their socioeconomic status was assessed using the Modified Kuppuswamy Scale. RESULTS: Ninety percent of patients with ROM had diabetes mellitus. The majority (44%) of patients belonged to lower socioeconomic strata. Higher frequencies of severe depression (28%), extremely severe anxiety (26%), and mild stress (17%) were noted in the study participants. On the Tukey test, depression score was higher in patients of ROM compared to COVID (with ROM) (p-value= 0.016). On Tukey analysis, anxiety score was significantly higher in ROM patients compared to COVID (with ROM) patients (p-value = 0.018). Coping scores were significantly higher in COVID (with ROM) patients compared to ROM patients (p value = 0.035). Mild to moderate visual disability was noted in the study participants.  Conclusion: The current study reflects the association of higher depression and anxiety scores in cases with ROM that indicated higher mental health needs. Early assessment, early detection, and early intervention for psychological help, along with the multidisciplinary team, helped to improve the overall psychological outcome of the affected patients.

Evaluation of Osmotolerant Potential of Halomonas sulfidaeris MV-19 Isolated from a Mud Volcano.

Salinity is one of the major challenges for cultivation of crops in a sustainable way because it severely affects plant growth and yield. Keeping this challenge in view, in the current study, a salt-tolerant Halomonas MV-19 was isolated from an extreme niche of mud volcano of Andaman Nicobar Island, India and identified on the basis of standard morphological, biochemical, and physiological tests and identified as Halomonas sulfidaeris strain MV-19 by 16S rRNA gene sequencing. The bacterium can grow on nutrient agar and nutrient broth supplemented with 3.5 M (≥ 20%) sodium chloride (NaCl). Sugar utilization assay revealed that H. sulfidaeris MV-19 utilizes only three sugars (dextrose, fructose, and mannose) from among twenty four tested sugars. The best growth of H. sulfidaeris MV-19 was observed in nutrient broth supplemented with 8% NaCl. When the broth was supplemented with dextrose, fructose, and mannose, the H. sulfidaeris MV-19 grew maximally in nutrient broth supplemented with 8% NaCl and 5% fructose. This strain produced exopolysaccharides (EPS) in nutrient broth supplemented with 8% NaCl and sugars (dextrose, fructose, and mannose). The EPS production was increased by 350% (three and half time) after addition of 5% fructose in nutrient broth compare with the EPS production in nutrient broth without supplemented with sugars. H. sulfidaeris MV-19 strain can produce EPS, which can help aggregate soil particle and reduced osmotic potential in soil, thus, be useful in alleviation of salinity stress in different crops cultivated in saline soils. The findings of the current investigation are expected to contribute towards effective abiotic stress management.

Corneal manifestations and treatment among patients with COVID-19-associated rhino-orbito-cerebral mucormycosis.

Purpose: TO report the corneal manifestations in patients with COVID-19-associated rhino-orbito-cerebral mucormycosis (ROCM). Methods: This study was a retrospective, observational, and record-based analysis of patients of ROCM with corneal involvement. Results: A total of 220 patients were diagnosed with ROCM over a period of 3 months. Thirty-two patients had developed corneal manifestations. The mean age at diagnosis was 52.84 ± 12.8 years. The associated risk factors were systemic mucormycosis, uncontrolled diabetes, recent COVID-19 infection, and injudicious use of systemic steroids. Twenty-nine patients were known diabetics, 32 had recent COVID-19 infection, and 13 gave a history of injudicious use of steroids. The right eye (RE) was affected in nine patients, the left eye (LE) in 20 patients, and both eyes in three patients. Nine patients had a round-oval corneal ulcer. One patient each had a perforated corneal ulcer with uveal prolapse, sealed perforated corneal ulcer, spontaneously healed limbal perforation, diffuse corneal haze with hyphemia, panophthalmitis, diffuse corneal stromal abscess, limbal ischemia, anterior uveitis with posterior synechiae, inferior corneal facet, and filamentary keratitis. Three patients each had a corneal melt and inferior conjunctival xerosis with chemosis. Orbital exenteration was performed in six patients. Five patients with corneal ulcers healed. Topical eye drops of amphotericin (0.5 mg/ml) cycloplegic, antiglaucoma medications, and lubricant eye drops were started along with systemic antifungals. Conclusion: Central corneal ulcer was the most common manifestation of mucormycosis. A concentration as low as 0.5 mg/ml of amphotericin eye drops was effective in the treatment.

Low Dose Atropine in Preventing the Progression of Childhood Myopia: A Randomised Controlled Trial.

PURPOSE: To study the efficacy of low dose atropine (0.01%) eye drops in preventing myopia progression in children by comparing the mean change in spherical equivalent (diopter) and axial length (mm) over a period of one year to a control group and study its effect on near vision, pupil size, keratometry and pachymetry. METHODS: 200 eyes of 100 myopic children were randomized into two groups based on a computer-generated random number table. The treatment group was administered 0.01% atropine eye drop once at bedtime and control group was administered a placebo. The follow up was done 3-monthly for 12 months by assessing the mean change in spherical equivalent and mean change in axial length. Other parameters like near vision, pupil size, keratometry and pachymetry were assessed at each follow up. RESULT: The study was age and sex matched. The mean change in spherical equivalent refraction and axial length was significantly lower in the treatment group (0.31 ± 0.55 D; 0.11 ± 0.22 mm) than the placebo group (0.80 ± 1.65 D; 0.23 ± 0.44 D) (p-value: 0.003). Less steepening of the corneal curvature was observed in the treatment group (0.16 ± 0.28 D vs 0.29 ± 0.3 D; p < 0.001) and the mean change in pachymetry was comparable between the groups (0.00 ± 0.01) (p-value 0.489). No significant change was seen in near vision (96% of the eyes with atropine had no change in near vision; 2% of the eyes had a change of near vision by one line (p-value 0.500); 2% had a change by 3 lines (p-value: 0.07) or pupil size following treatment. CONCLUSION: The use of 0.01% atropine eye drop reduced the progression of myopia over the study period of one year with no significant changes in near vision, pupil size. No patient reported any systemic and local side effects with administration of 0.01% atropine eye drop.

Retrospective analysis of the role of retrobulbar amphotericin-B injection in the management of COVID-19 associated rhino-orbito-cerebral-mucormycosis.

Introduction: Rhino-orbito-cerebral-mucormycosis (ROCM) is the most common form of mucormycosis observed during the second wave of COVID-19 where a steep rise in the number of cases was seen. The orbital form is almost always associated with fungal sinusitis. Among the various treatment modalities available, the role of retrobulbar Amphotericin-B injections is under-reported. This study is conducted to determine the role of transcutaneous retrobulbar amphotericin-B (TRAMB) in the management of COVID-19 associated ROCM. Methods: a retrospective analysis of 61 patients of COVID-19 associated ROCM was done, who met the inclusion criteria and presented to a tertiary care center, between May to August 2021. These patients were administered TRAMB (deoxycholate/emulsion form) along-with systemic amphotericin B. All the patients were evaluated for clinical improvement. Results: out of 61 patients, 58 (95.08%) showed overall improvement. 40 patients (65.57%) stabilized or improved clinically and 3 patients succumbed to the illness due to advanced systemic mucormycosis and acute kidney failure. Sixteen out of 58 patients underwent orbital exenteration. Out of remaining 43 patients, 35 showed complete recovery of orbital and ocular disease and the disease stabilized in eight patients. Seven patients demonstrated TRAMB associated ocular complications which however completely resolved in six patients. Conclusion: to the best of the author´s knowledge, regression of orbital mucormycosis with improvement in ptosis, proptosis, ocular motility and stabilization of visual acuity are scarcely reported in literature. Further TRAMB as a globe non-deforming treatment modality is an option available for ROCM.

ROS generated from biotic stress: Effects on plants and alleviation by endophytic microbes.

Aerobic living is thought to generate reactive oxygen species (ROS), which are an inevitable chemical component. They are produced exclusively in cellular compartments in aerobic metabolism involving significant energy transfer and are regarded as by-products. ROS have a significant role in plant response to pathogenic stress, but the pattern varies between necrotrophs and biotrophs. A fine-tuned systemic induction system is involved in ROS-mediated disease development in plants. In regulated concentrations, ROS act as a signaling molecule and activate different pathways to suppress the pathogens. However, an excess of these ROS is deleterious to the plant system. Along with altering cell structure, ROS cause a variety of physiological reactions in plants that lower plant yield. ROS also degrade proteins, enzymes, nucleic acids, and other substances. Plants have their own mechanisms to overcome excess ROS and maintain homeostasis. Microbes, especially endophytes, have been reported to maintain ROS homeostasis in both biotic and abiotic stresses by multiple mechanisms. Endophytes themselves produce antioxidant compounds and also induce host plant machinery to supplement ROS scavenging. The structured reviews on how endophytes play a role in ROS homeostasis under biotic stress were very meager, so an attempt was made to compile the recent developments in ROS homeostasis using endophytes. This review deals with ROS production, mechanisms involved in ROS signaling, host plant mechanisms in alleviating oxidative stress, and the roles of endophytes in maintaining ROS homeostasis under biotic stress.

Endophytic Bacillus subtilis antagonize soil-borne fungal pathogens and suppress wilt complex disease in chickpea plants (Cicer arietinum L.).

The present study aimed to identify potential endophytic bacteria antagonistic against three soil-borne fungal pathogens, Rhizoctonia solani, Sclerotium rolfsii, and Fusarium oxysporum f.sp. ciceri causing root rot, collar rot, and fungal wilt diseases in chickpea plants, respectively. A total of 255 bacterial endophytes were isolated from the leaves, stems, and roots of seven different crop plants (chickpea, tomato, wheat, berseem, mustard, potato, and green pea). The dual culture-based screening for antifungal properties indicated that three endophytic isolates had strong inhibition (>50%) against all three pathogens tested. Based on morphological, biochemical, and molecular characterization, the selected isolates (TRO4, CLO5, and PLO3) were identified as different strains of Bacillus subtilis. The bacterial endophytes (TRO4 and CLO5) were positive for plant growth promoting (PGP) traits viz., ammonia, siderophore, and indole-3-acetic acid (IAA) production. The bio-efficacy of the endophytes (TRO4, CLO5, and PLO3) was tested by an in planta trial in chickpea pre-challenged with R. solani, S. rolfsii, and F. oxysporum f.sp. ciceri. The B. subtilis strains TRO4 and CLO5 were found to be effective in reducing percent disease incidence (p ≤ 0.05) and enhancing plant growth parameters. The different root parameters viz. root length (mm), surface area (cm2), root diameter (mm), and root volume (cm3) were significantly (p ≤ 0.05) increased in TRO4 and CLO5 inoculated chickpea plants. Confocal Scanning Laser Microscopy showed heavy colonization of bacteria in the roots of endophyte-inoculated chickpea plants. The inoculation of endophytic Bacillus subtilis strains TRO4 and CLO5 in chickpea plants through seed biopriming reduced the accumulation of superoxide, enhanced the plant defense enzymes, and induced the expression of Pathogenesis-Related (PR) genes. Semi-quantitative analysis of defense-related genes showed differential activation of PR genes (60srp and IFR) by endophyte inoculation. The results of the present study reveal the antagonistic potential of B. subtilis strains TRO4 and CLO5 against three major soil-borne fungal pathogens and their ability to suppress wilt complex disease in chickpea plants. This is the first report on the simultaneous suppression of three major soil-borne fungal pathogens causing wilt complex in chickpea plants by endophytic B. subtilis strains.

Endophytic Burkholderia: Multifunctional roles in plant growth promotion and stress tolerance.

The genus Burkholderia has proven potential in improving plant performance. In recent decades, a huge diversity of Burkholderia spp. have been reported with diverse capabilities of plant symbiosis which could be harnessed to enhance plant growth and development. Colonization of endophytic Burkholderia spp. have been extensively studied through techniques like advanced microscopy, fluorescent labelling, PCR based assays, etc., and found to be systemically distributed in plants. Thus, use of these biostimulant microbes holds the promise of improving quality and quantity of crops. The endophytic Burkholderia spp. have been found to support plant functions along with boosting nutrient availability, especially under stress. Endophytic Burkholderia spp. improve plant survival against deadly pathogens via mechanisms like competition, induced systemic resistance, and antibiosis. At the same time, they are reported to extend plant tolerance towards multiple abiotic stresses especially drought, salinity, and cold. Several attempts have been made to decipher the potential of Burkholderia spp. by genome mining, and these bacteria have been found to harbour genes for plant symbiosis and for providing multiple benefits to host plants. Characteristics specific for host recognition and nutrient acquisition were confirmed in endophytic Burkholderia by genomics and proteomics-based studies. This could pave the way for harnessing Burkholderia spp. for biotechnological applications like biotransformation, phytoremediation, insecticidal activity, antimicrobials, etc. All these make Burkholderia spp. a promising microbial agent in improving plant performance under multiple adversities. Thus, the present review highlights critical roles of endophytic Burkholderia spp., their colonization, alleviation of biotic and abiotic stresses, biotechnological applications and genomic insights.

Linking Soil Microbial Diversity to Modern Agriculture Practices: A Review.

Agriculture is a multifarious interface between plants and associated microorganisms. In contemporary agriculture, emphasis is being given to environmentally friendly approaches, particularly in developing countries, to enhance sustainability of the system with the least negative effects on produce quality and quantity. Modern agricultural practices such as extensive tillage, the use of harmful agrochemicals, mono-cropping, etc. have been found to influence soil microbial community structure and soil sustainability. On the other hand, the question of feeding the ever-growing global population while ensuring system sustainability largely remains unanswered. Agriculturally important microorganisms are envisaged to play important roles in various measures to raise a healthy and remunerative crop, including integrated nutrient management, as well as disease and pest management to cut down agrochemicals without compromising the agricultural production. These beneficial microorganisms seem to have every potential to provide an alternative opportunity to overcome the ill effects of various components of traditional agriculture being practiced by and large. Despite an increased awareness of the importance of organically produced food, farmers in developing countries still tend to apply inorganic chemical fertilizers and toxic chemical pesticides beyond the recommended doses. Nutrient uptake enhancement, biocontrol of pests and diseases using microbial inoculants may replace/reduce agrochemicals in agricultural production system. The present review aims to examine and discuss the shift in microbial population structure due to current agricultural practices and focuses on the development of a sustainable agricultural system employing the tremendous untapped potential of the microbial world.

Surface sterilization for isolation of endophytes: Ensuring what (not) to grow.

Endophytic microbiota opens a magnificent arena of metabolites that served as a potential source of medicines for treating a variety of ailments and having prospective uses in agriculture, food, cosmetics, and many more. There are umpteen reports of endophytes improving the growth and tolerance of plants. In addition, endophytes from lifesaving drug-producing plants such as Taxus, Nothapodytes, Catharanthus, and so forth have the ability to produce host mimicking compounds. To harness these benefits, it is imperative to isolate the true endophytes, not the surface microflora. The foremost step in endophyte isolation is the removal of epiphytic microbes from plant tissues, called as surface sterilization. The success of surface sterilization decides "what to grow" (the endophytes) and "what not to grow" (the epiphytes). It is very crucial to use an appropriate sterilant solution, concentration, and exposure time to ensure thorough surface disinfection with minimal damage to the endophytic diversity. Commonly used surface sterilants include sodium hypochlorite (2%-10%), ethanol (70%-90%), mercuric chloride (0.1%), formaldehyde (40%), and so forth. In addition, the efficiency could further be improved by pretreatment with surfactants such as Triton X-100, Tween 80, and Tween 20. This review comprehensively deals with the various sterilants and sterilization methods for the isolation of endophytic microbes. In addition, the mechanisms and rationale behind using specific surface sterilants have also been elaborated at length.

Risk factors for severe rhino-orbital mucormycosis during its epidemic post-COVID-19 pandemic.

Postsecond wave of COVID-19 pandemic in the year 2021, rhino-orbital mucormycosis (ROM) was seen as an epidemic in the Indian community. Severe ROM disease has poor prognosis and requires a multidisciplinary approach for treatment. Hence, its prevention is better than cure. Studies done during the epidemic assessed predisposing factors, but this was a novel study which focused on assessing risk factors for severe disease of ROM. Ninety-four consecutive patients of ROM admitted at our designated nodal tertiary hospital of North India were enrolled, and data were collected and analyzed. Facial edema was the most common presenting complaint. Subclinical and mild COVID-19 infection was associated with severe ROM. Uncontrolled diabetes mellitus and prophylactic zinc supplementation were other significant risk factors for severe ROM. Public awareness among the general population for the above risk factors can prevent a debilitating disease like severe ROM.

Surgical success of 'W' shaped incision versus Tear Trough incision in External Dacryocystorhinostomy.

PURPOSE: To compare surgical success (cosmetic, anatomical & functional) of 'W' shaped incision versus tear-trough incision in external dacryocystorhinostomy (eDCR). METHODS: In a prospective study (November 2018 - March 2020), 61 eyes of chronic dacryocystitis underwent eDCR randomized into group T (30 eyes) & group W (31 eyes). The functional and objective cosmetic assessment was done at 3 months using Munk's and Devoto's scores respectively. The subjective cosmetic evaluation was done using a questionnaire. Grades 0-1 were considered the cosmetic and functional success after assessing the respective scores. The patent lacrimal passage was defined as anatomical success. RESULTS: Mean age was 40.1 ± 14.9 years with female preponderance. Intraoperative skin flap button-holing & reversible darkening of their apices were specific complications of Group W. In the early postoperative period, lid edema & epiphora were significantly more in group T (p < 0.05). The functional success rate in group T and W was 93.3% and 93.5%, respectively (p = 0.53). There was a 100% anatomical success rate in group T whereas 96.8% in group W (p = 0.51). The subjective cosmetic success rate was 83.3% in group T and 80.6% in group W (p = 0.78) while objective cosmetic success rate was 63.3% and 67.7% in group T and group W, respectively (p = 0.72). CONCLUSION: Surgical success in terms of cosmetic, anatomical & functional outcomes of W-shaped incision were comparable to the conventional Tear trough incision.

Salinity alleviator bacteria in rice (Oryza sativa L.), their colonization efficacy, and synergism with melatonin.

In this study, rhizospheric and endophytic bacteria were tested for the alleviation of salinity stress in rice. Endophytic isolates were taken from previous studies based on their salt stress-alleviating traits. The rhizospheric bacteria were isolated from rice and screened based on salt tolerance and plant growth-promoting traits. Molecular identification indicated the presence of class Gammaproteobacteria, Bacillota, and Actinomycetia. Two-two most potential isolates each from rhizospheric and endophytic bacteria were selected for in planta trials. Results showed that microbial inoculation significantly improved germination and seedling vigor under elevated salinity. The confocal scanning laser microscopy showed higher bacterial colonization in inoculated rice roots than in control. Based on this experiment, rhizospheric bacteria Brevibacterium frigoritolerans W19 and endophytic Bacillus safensis BTL5 were selected for pot trial along with a growth-inducing compound melatonin 20 ppm. Inoculation of these two bacteria improved the levels of chlorophyll, proline, phenylalanine ammonia-lyase, catalase, superoxide dismutase, polyphenol oxidase, root-shoot length, and dry weight under elevated salt concentration. The gene expression studies showed modulation of SOD1, CATa, NHX1, and PAL1 genes by the bacterial strains and melatonin application. The inoculation was found to have additive effects with 20 ppm melatonin. This enhancement in dry matter accumulation, compatible solute production, and oxidative stress regulation could help plants in mitigating the ill effects of high salinity. Exploring such a combination of microbes and inducer molecules could be potentially useful in developing stress-alleviating bioformulations.

Vertical Transmission of Diverse Cultivation-Recalcitrant Endophytic Bacteria Elucidated Using Watermelon Seed Embryos.

Seed transmission of endophytic microorganisms is a growing research area in plant biology and microbiology. We employed cultivation versus cultivation-independent approaches on excised embryos from watermelon seeds (6-12 months in storage) and on embryo-derived in vitro seedlings (EIVS) to assess the vertical transmission of endophytic bacteria. Surface-disinfected watermelon seeds bore abundant residual bacteria in the testa and perisperm tissues, predominantly Bacillus spp. propounding the essentiality of excluding all non-embryonic tissues for vertical transmission studies. Tissue homogenates from re-disinfected seed embryos displayed no cultivable bacteria during the 1-week monitoring. Bright-field live microscopy revealed abundant bacteria in tissue homogenates and in embryo sections as intracellular motile particles. Confocal imaging on embryo sections after SYTO-9 staining and eubacterial fluorescent in situ hybridization (FISH) endorsed enormous bacterial colonization. Quantitative Insights Into Microbial Ecology (QIIME)-based 16S rRNA V3-V4 taxonomic profiling excluding the preponderant chloroplast and mitochondrial sequences revealed a high bacterial diversity in watermelon seed embryos mainly Firmicutes barring spore formers followed by Proteobacteria, Bacteroidetes, and Actinobacteria, and other minor phyla. Embryo-base (comprising the radicle plus plumule parts) and embryo-cotyledon parts differed in bacterial profiles with the abundance of Firmicutes in the former and Proteobacteria dominance in the latter. EIVS displayed a higher bacterial diversity over seed embryos indicating the activation from the dormant stage of more organisms in seedlings or their better amenability to DNA techniques. It also indicated embryo-to-seedling bacterial transmission, varying taxonomic abundances for seed embryos and seedlings, and differing phylogenic profiles for root, hypocotyl, and cotyledon/shoot-tip tissues. Investigations on different watermelon cultivars confirmed the embryo transmission of diverse cultivation recalcitrant endophytic bacteria. Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes formed the core phyla across different cultivars with 80-90% similarity at genus to phylum levels. Conversely, freshly harvested seeds displayed a dominance of Proteobacteria. The findings revealed that dicot seeds such as in different watermelon cultivars come packaged with abundant and diverse vertical and seedling-transmissible cultivation recalcitrant endophytic bacteria with significant implications for plant biology.

Inter-Genera Colonization of Ocimum tenuiflorum Endophytes in Tomato and Their Complementary Effects on Na+/K+ Balance, Oxidative Stress Regulation, and Root Architecture Under Elevated Soil Salinity.

Endophytic bacilli of ethano-botanical plant Ocimum tenuiflorum were screened for salt stress-alleviating traits in tomato. Four promising O. tenuiflorum endophytes (Bacillus safensis BTL5, Bacillus haynesii GTR8, Bacillus paralicheniformis GTR11, and Bacillus altitudinis GTS16) were used in this study. Confocal scanning laser microscopic studies revealed the inter-genera colonization of O. tenuiflorum endophytes in tomato plants, giving insights for widening the applicability of potential endophytes to other crops. Furthermore, in a pot trial under 150 mM NaCl concentration, the inoculated endophytes contributed in reducing salt toxicity and improving recovery from salt-induced oxidative stress by different mechanisms. Reduction in reactive oxygen species (ROS) (sub-cellular H2O2 and superoxide) accumulation was observed besides lowering programmed cell death and increasing chlorophyll content. Endophyte inoculation supplemented the plant antioxidant enzyme system via the modulation of enzymatic antioxidants, viz., peroxidase, ascorbate peroxidase, superoxide dismutase, and catalase, apart from increasing proline and total phenolics. Antioxidants like proline have dual roles of antioxidants and osmoregulation, which might also have contributed to improved water relation under elevated salinity. Root architecture, viz., root length, projection area, surface area, average diameter, tips, forks, crossings, and the number of links, was improved upon inoculation, indicating healthy root growth and enhanced nutrient flow and water homeostasis. Regulation of Na+/K+ balance and water homeostasis in the plants were also evident from the modulation in the expression of abiotic stress-responsive genes, viz., LKT1, NHX1, SOS1, LePIP2, SlERF16, and SlWRKY39. Shoot tissues staining with light-excitable Na+ indicator Sodium GreenTM Tetra (tetramethylammonium) salt showed low sodium transport and accumulation in endophyte-inoculated plants. All four endophytes exhibited different mechanisms for stress alleviation and indicated complementary effects on plant growth. Furthermore, this could be harnessed in the form of a consortium for salt stress alleviation. The present study established inter-genera colonization of O. tenuiflorum endophytes in tomato and revealed its potential in maintaining Na+/K+ balance, reducing ROS, and improving root architecture under elevated salinity.