Molecular approaches for the management of papaya ringspot virus infecting papaya: a comprehensive review.

Papaya ringspot virus (PRSV) is a catastrophic disease that causes huge yield losses in papaya cultivation around the world. Yield losses in severely infected plants can be upto 100%. Because of this disease, papaya cultivation has been shifted to other crops in some areas of the world. Many conventional methods and breeding approaches are used against this disease, which turns out to be less effective. Considering the yield loss caused by PRSV in papaya, it is high time to focus on alternative control methods. To implement effective management strategies, molecular approaches such as Marker Assisted Breeding (MAS) or transgenic methods involving post-transcriptional gene silencing targeting the genome viz., coat protein, replicase gene, or HC Pro can be pursued. However, the public's reluctance to widely accept the transgenic approach due to health and environmental concerns necessitates a consideration of non-transgenic alternatives. Prioritizing safety and ensuring efficient virus control, non-transgenic approaches which encompass cross-protection, genome editing, and topical applications of dsRNA to induce gene silencing within the host, can be adopted. This review aims to provide comprehensive insights of various molecular tools used in managing PRSV which in turn will help in sustainable agriculture.

Consortia of Streptomyces spp. triggers defense/PAMP genes during the interaction of Groundnut bud necrosis orthotospovirus in tomato.

In the present study, Streptomyces spp. were isolated, characterized, and the efficacy was tested against Groundnut bud necrosis orthotospovirus (GBNV) in tomato. Among the three inoculation methods viz., pre-, post-, and simultaneous inoculation, tested for antiviral efficacy, pre-inoculation spray of the three Streptomyces spp. viz., Streptomyces mutabilis, Streptomyces rochei, and Streptomyces chrestomyceticus (SAT1, SAT4, and STR2) recorded the least disease severity index (DSI) of GBNV in tomato. In the pot culture, seed treatment of liquid consortium of three Streptomyces spp. @ 2 ml/g of seeds along with seedling dip at 10 ml/lit followed by soil drenching at 10 ml/lit on 7 days after transplanting (DAT) and foliar application at 0.5% on 15 DAT, 30 DAT, and 45 DAT recorded the least GBNV infection of 15% DSI and 16.67% DSI in trial I and II respectively. Besides, under field conditions, the disease incidence was reduced to 14.44% recording a higher yield of 76.67 t/ha in the treated plants against 63.99 t/ha in control. Upregulation of defense genes viz., PR1, PR2, PR6, WRKY, MAPKK, and NPR1 during tripartite interaction between tomato, Streptomyces, and GBNV was analyzed by qRTPCR, indicating that the consortia could decrease the virus severity through induced systemic resistance pathways. Thus, it is concluded that Streptomyces spp. can be used for the management of GBNV in tomato. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04030-6.

A Bi2Te3 topological insulator/carbon nanotubes hybrid composites as a new counter electrode material for DSSC and NIR photodetector application.

Two-dimensional layered bismuth telluride (Bi2Te3), a prominent topological insulator, has garnered global scientific attention for its unique properties and potential applications in optoelectronics and electrochemical devices. Notably, there is a growing emphasis on improving photon-to-electron conversion efficiency in dye-sensitized solar cells (DSSCs), prompting the exploration of alternatives to noble metal catalysts like platinum (Pt). This study presents the synthesis of Bi2Te3 and its hybrid nanostructure with single-wall carbon nanotubes (SWCNT) via a straightforward hydrothermal process. The research unveils a novel application for the Bi2Te3-SWCNT hybrid structure, serving as a counter electrode in platinum-free DSSCs, facilitating the conversion of triiodide (I3-) to iodide (I-) and functioning as an active electrode material in a photodetector (n-Bi2Te3-SWCNT/p-Si). The resulting DSSC employing the Bi2Te3-SWCNT hybrid counter electrode achieves a power conversion efficiency (PCE) of 4.2 %, a photocurrent density of 10.5 mA/cm2, a fill factor (FF) of 62 %, and superior charge transfer kinetics compared to pristine Bi2Te3 based counter electrode (PCE 2.1 %, FF 34 %). Additionally, a spin coating technique enhances the performance of the n-Bi2Te3-SWCNT/p-Si photodetector, yielding a responsivity of 2.2 AW-1, detectivity of 1.2 × 10-3 and enhanced external quantum efficiency. These findings demonstrate that the newly developed Bi2Te3-SWCNT heterostructure enhances interfacial charge transport, electrocatalytic performance in DSSCs, and overall photodetector performance.

Profiling of Groundnut bud necrosis orthotospovirus-responsive microRNA and their targets in tomato based on deep sequencing.

Tomato, an extensively cultivated vegetable crop produces miRNAs in response to infection with Groundnut bud necrosis orthotospovirus, a viral pathogen causing significant economic losses. High-throughput miRNA sequencing was performed on tomato leaves inoculated with GBNV and mock-inoculated leaves as controls. Analysis revealed 73 known miRNAs belonging to 24 miRNA families, with variable expression levels. Interestingly, 39 miRNAs were upregulated, and 34 were downregulated in response to GBNV infection. Stem-loop quantitative reverse transcription PCR validated the differential expression of selected miRNAs. Additionally, 30 miRNA encoded proteins were identified to be involved in disease resistance and susceptibility. The miRNA-target interactions were found to play significant roles in cellular and metabolic activities, as well as modulating signaling pathways during the plant-virus interaction. The findings shed light on the intricate regulatory network of miRNAs in tomato response to viral infection and may contribute to developing strategies for improving crop protection against viral diseases.

Ultrasensitive and reversible NO2 gas sensor based on SnS2/TiO2 heterostructures for room temperature applications.

Nitrogen dioxide (NO2) is one of the toxic gases produced by chemical industries, power plants, and vehicles. In this work, we demonstrate an inexpensive sensing platform for NO2 detection at room temperature (RT-32 °C) based on a charge transfer mechanism. Three-dimensional hierarchical SnS2 and SnS2/mesoporous TiO2 nanocomposites were synthesized via the solvothermal method. SnS2/20 wt% mesoporous TiO2 nanocomposites sample showed 245.4% enhanced response compared to pristine SnS2. The fabricated device exhibits excellent selectivity among all other interfering gases with one-month stability. The rapid response and enhanced response achieved were obtained for the minimum concentration of 2 ppm NO2. The formation of heterojunction between SnS2 and mesoporous TiO2 has a synergetic effect, providing more active sites and porous structures for the detection of NO2 gas molecules.

Interface engineering of heterogeneous NiMn layered double hydroxide/vertically aligned NiCo2S4 nanosheet as highly efficient hybrid electrocatalyst for overall seawater splitting.

We report the fabrication of a heterogeneous catalyst through vertically aligned NiCo2S4/Ni3S2 nanosheet with encapsulation of ultrathin NiMn layered double hydroxide over self-standing nickel foam (NM/NCS/NS/NF) via two-step hydrothermal processes. Benefiting from more adequate catalytic active centres and copious interfacial charge transfer channels, NM/NCS/NS/NF electrode demonstrates superior bifunctional activity for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) processes under alkaline fresh/simulated seawater electrolyte conditions. As a result, NM/NCS/NS/NF electrode requires the smallest overpotentials of 282 & 312 mV (OER) and 171 & 204 mV (HER) to attain current densities of 30 & 50 mA cm-2 respectively under alkaline simulated seawater electrolyte conditions. Besides, the presence of amorphous NiMn LDH layers over crystalline NiCo2S4/Ni3S2 catalyst stimulates surface adsorption of oxygen intermediate species, water dissociate ability on catalytic active centres, and mass transport with electron transfer at the interface. Further, the two-electrode configuration assisted electrolyser system delivers an efficient overall water splitting activity with minimum cell voltages of 1.54 V (in 1 M KOH) and 1.56 V (in 1 M KOH+0.5 M NaCl) at a current density of 10 mA cm-2. Besides, a fabricated electrolyser cell provides a more sustained water electrolysis process and robust durability for 20 h which displays NM/NCS/NS/NF electrode is a vibrant and potential candidate for realistic seawater electrolysis. Therefore, our proposed heterogeneous electrocatalyst could open up a new platform for developing efficient large-scale efficient seawater electrolysis.

Electrochemical Investigations of Double Perovskite M2NiMnO6 (Where M = Eu, Gd, Tb) for High-Performance Oxygen Evolution Reaction.

Double perovskites are known for their special structures which can be utilized as catalyst electrode materials for electrochemical water splitting to generate carbon-neutral hydrogen energy. In this work, we prepared lanthanide series metal-doped double perovskites at the M site such as M2NiMnO6 (where M = Eu, Gd, Tb) using the solid-state reaction method, and they were investigated for an oxygen evolution reaction (OER) study in an alkaline medium. It is revealed that the catalyst with a configuration of Tb2NiMnO6 has outstanding OER properties such as a low overpotential of 288 mV to achieve a current density of 10 mAcm-2, a lower Tafel slope of 38.76 mVdec-1, and a long cycling stability over 100 h of continuous operation. A-site doping causes an alteration in the oxidation or valence states of the NiMn cations, their porosity, and the oxygen vacancies. This is evidenced in terms of the Mn4+/Mn3+ ratio modifying electronic properties and the surface which facilitates the OER properties of the catalyst. This is discussed using electrochemical impedance spectroscopy (EIS) and electrochemical surface area (ECSA) of the catalysts. The proposed work is promising for the synthesis and utilization of future catalyst electrodes for high-performance electrochemical water splitting.

An improved Shorea robusta genomic DNA extraction protocol with high PCR fidelity.

Shorea robusta (Dipterocarpaceae), commonly known as Sal, is an economically and culturally important timber species, known to contain a wide spectrum of polyphenols, polysaccharides, and other secondary metabolites in the tissues, which can interfere with the extraction of high-quality genomic DNA. In order to screen simple sequence repeat (SSR) markers and carry out other DNA-based analyses for this species in our laboratory, a high-throughput DNA extraction methodology was needed. Hence, we have optimized a simple, rapid, safe, and reliable high-throughput protocol for DNA extraction suitable for both fresh and dry leaves. The standardized protocol delivered good DNA yield of ∼1500 µg from 1 g of leaf tissue, with purity indicated by a 260 nm/280 nm absorbance ratio ranging from 1.70 to 1.91, which validated the suitability of extracted DNA and revealed reduced levels of contaminants. Additionally, the protocol that we developed was found to be suitable for polymerase chain reaction (PCR) amplification using microsatellite markers. Genome-wide characterization with SSR markers has been established in S. robusta, which further validates the protocol and its usefulness in DNA-based studies across the genus and/or family.

Copper(I) Complexes of Amide Functionalized Bisphosphine: Proximity Enhanced Metal-Ligand Cooperativity and Its Catalytic Advantage in C(sp3)-H Bond Activation of Unactivated Cycloalkanes in Dehydrogenative Carboxylation Reactions.

The reactions of amide functionalized bisphosphine, o-Ph2PC6H4C-(O)N(H)C6H4PPh2-o (1) (BalaHariPhos), with copper salts is described. Treatment of 1 with CuX in a 1:1 molar ratio yielded chelate complexes of the type [CuX{(o-Ph2PC6H4C(O)N(H)C6H4PPh2-o)}-κ2-P,P] (X = Cl, 2; Br, 3; and I, 4), which on subsequent treatment with KOtBu resulted in a dimeric complex [Cu(o-Ph2PC6H4C(O)(N)C6H4PPh2-o)]2 (5). Interestingly, complexes 2-4 showed weak N-H···Cu interactions. These weak H-bonding interactions are studied in detail both experimentally and computationally. Also, CuI complexes 2-5 were employed in the oxidative dehydrogenative carboxylation (ODC) of unactivated cycloalkanes in the presence of carboxylic acids to form the corresponding allylic esters. Among complexes 2-5, halide-free dimeric CuI complex 5 showed excellent metal-ligand cooperativity in the oxidative dehydrogenative carboxylation (ODC) in the presence of carboxylic acids to form the corresponding allylic esters through C(sp3)-H bond activation of unactivated cycloalkanes. Mechanistic details of the catalytic process were established by isolating the precatalyst [Cu{(o-Ph2PC6H4C(O)(NH)C6H4PPh2-o)-κ2-P,P}(OOCPh)] (6) and fully characterized by mass spectrometry, NMR data, and single-crystal X-ray analysis. Density functional theory-based calculations further provided a quantitative understanding of the energetics of a series of H atom transfer steps occurring in the catalytic cycle.

A Comparative Evaluation of Dissolution Rate of Three Different Posterior Restorative Materials used in Pediatric Dentistry: An In Vitro Study.

Aim: The study aimed to compare and assess the dissolution rate, color stability, and other mechanical parameters, such as compressive and flexural strength, of three distinct posterior restorative materials used in pediatric dentistry. Materials and methods: The three posterior restorative materials used in pediatric dentistry are divided into group I-Zirconomer, group II-Composite, and group III-Cention N. Around 111 cylindrical specimens were grouped into three groups of 37 each. According to the manufacturer's standards, all materials were proportioned and handled. The materials were thermocycler in a chewing simulator and were subjected to various tests to estimate the dissolution rate, compressive strength, flexural strength, and color stability of the three individual groups. Results: The dissolution rate was highest in Zirconomer, followed by Cention N and Composite, which were highly significant (p = 0.05). Compressive strength was highest with Cention N, followed by Composite and Zirconomer, which was highly important (p = 0.05). Cention N had the greatest flexural strength, followed by Composite and Zirconomer, which were highly significant (p = 0.05). Finally, the Composite had the highest color stability, followed by Cention N and Zirconomer among the three groups. Conclusion: It is concluded that resin-based restorative materials outperform glass ionomer-based Zirconomer cement in terms of dissolution rate, compressive strength, flexural strength, and color stability. Clinical significance: Because of the widespread improvement in dental materials, many dental restorative types of cement have emerged on the market. The features of good restorative materials are mechanical strength, fluid dissolution rate, and retention. How to cite this article: Raman V, Srinivasan D, AR SE, et al. A Comparative Evaluation of Dissolution Rate of Three Different Posterior Restorative Materials used in Pediatric Dentistry: An In Vitro Study. Int J Clin Pediatr Dent 2023;16(S-1):S20-S26.

Solvent-assisted synthesis of Ag2Se and Ag2S nanoparticles on carbon fabric for enhanced thermoelectric performance.

The challenge of developing low-cost, highly flexible, and high-performance thermoelectric (TE) materials persists due to the low thermoelectric efficiency of conducting polymers and the inflexibility of inorganic materials. In this study, we successfully integrated Ag2Se and Ag2S with highly conductive carbon fabric (CF) to produce a flexible thermoelectric material. A facile one-step solvothermal method was employed to synthesize the Ag2Se-CF and Ag2S-CF, which were then subjected to X-ray analysis to confine the phase formation of Ag2Se and Ag2S on the carbon fabric. The analysis revealed that Ag2Se and Ag2S nanoparticles were tightly packed on the surface of carbon fabric, and compositional analysis confirmed the interaction between the material and carbon fabric. The thermoelectric properties of Ag2Se-CF and Ag2S-CF were significantly altered due to carrier concentration and mobility variations, resulting in a low power factor of 6.7 µW/mK2 for Ag2Se-CF and a high-power factor of 24 µW/mK2 at 373 K for Ag2S-CF. The growth of Ag2Se-CF and Ag2S-CF on carbon fabric led to an enhancement in their thermoelectric properties. Further, TE legs were fabricated using the Ag2Se-CF (p-type) and Ag2S-CF (n-type), and the fabricated legs exhibited an output voltage of âˆ¼20 mV to âˆ¼86.65 mV at a temperature gradient (ΔT) of 3-8 K. This work represents a cutting-edge approach to the fabrication of high-performance, wearable thermoelectric devices.

Ultra-high power factor of p-type Bi2Se3 for room-temperature thermoelectric applications.

Achieving high zT in n-type and p-type thermoelements in similar compounds is a great challenge for device construction. Herein, we report a high-power factor of 480 µW/mK2 in Ga and Mn co-doped Bi2Se3 along with a maximum zT of 0.25 at 303 K as a p-type thermoelement. The co-doped Ga and Mn play distinct roles in enhancing the hole concentration to 1.6 × 1019 cm-3 with a maximized effective mass. In addition, a drastic reduction in lattice thermal conductivity of 0.5 W/mK is attained due to point defects of mass and strain field fluctuation scattering in Bi2Se3.

First record of Cladosporium oxysporum as a potential novel fungal hyperparasite of Melampsora medusae f. sp. deltoidae and screening of Populus deltoides clones against leaf rust.

Melampsora medusae f. sp. deltoidae is causing serious foliar rust disease on Populus deltoides clones in India. In the present study, a novel fungal hyperparasite on M. medusae has been reported. The hyperparasitic fungus was isolated from the uredeniospores of the rust fungi and identified as Cladosporium oxysporum by morphological characterization and DNA barcode technique based on the Internal Transcribed Spacer (ITS) region of nrDNA and beta-tubulin (TUB) gene region. Hyperparasitism was further confirmed through leaf assay and cavity slide methods. Leaf assay method showed no adverse effect of C. oxysporum on poplar leaves. However, the mean germination percentage of urediniospores was significantly decreased (p < 0.05) in the cavity slide method when a conidial suspension (1.5 × 107 conidia per ml) of C. oxysporum was applied in different deposition sequences. Scanning and light microscopic observations were made to explore the mode of action of the hyperparasitism. The antagonistic fungus vividly showed three different types of antagonism mechanisms, including enzymatic, direct, and contact parasitism. Alternatively, by screening 25 high-yielding clones of P. deltoides, five clones (FRI-FS-83, FRI-FS-92, FRI-FS-140, FRI-AM-111, and D-121) were enlisted under highly resistant category. Present study revealed an antagonistic relationship between C. oxysporum and M. medusae, which could be an effective method of biocontrol in field plantations of poplar. Combining this biocontrol approach with the use of resistant host germplasm could be an environment friendly strategy for preventing foliar rust and increasing poplar productivity in northern India. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03623-x.

Ecological niche modelling and population genetic analysis of Indian temperate bamboo Drepanostachyum falcatum in the western Himalayas.

The present study was conducted to understand the key ecological and biological questions of conservation importance in Drepanostachyum falcatum which aimed to map potential distribution in the western Himalayas and decipher spatial genetic structure. Eco-distribution maps were generated through ecological niche modelling using the Maximum Entropy (MaxEnt) algorithm implemented with 228 geocoordinates of species presence and 12 bioclimatic variables. Concomitantly, 26 natural populations in the western Himalayas were genetically analysed using ten genomic sequence-tagged microsatellite (STMS) markers. Model-derived distribution was adequately supported with appropriate statistical measures, such as area under the 'receiver operating characteristics (ROC)' curve (AUC; 0.917 ± 0.034)", Kappa (K; 0.418), normalized mutual information (NMI; 0.673) and true skill statistic (TSS; 0.715). Further, Jackknife test and response curves showed that the precipitation (pre- and post-monsoon) and temperature (average throughout the year and pre-monsoon) maximize the probabilistic distribution of D. falcatum. We recorded a wide and abundant (4096.86 km2) distribution of D. falcatum in the western Himalayas with maximum occurrence at 1500 to 2500 m asl. Furthermore, marker analysis exemplified high gene diversity with low genetic differentiation in D. falcatum. Relatively, the populations of Uttarakhand are more genetically diverse than Himachal Pradesh, whereas within the Uttarakhand, the Garhwal region captured a higher allelic diversity than Kumaon. Clustering and structure analysis indicated two major gene pools, where genetic admixing appeared to be controlled by long-distance gene flow, horizontal geographical distance, aspect, and precipitation. Both the species distribution map and population genetic structure derived herein may serve as valuable resources for conservation and management of Himalayan hill bamboos.

Small polaron hopping conduction mechanism and enhanced thermoelectric power factor in the perovskite LaCoO3 ceramic.

Among the various thermoelectric oxide materials, perovskites offer more flexibility to adjust the interdependent thermoelectric parameters for an improved thermoelectric performance. In this work, we investigated the effect of A-site cation deficiency and Sr-substitution on the thermoelectric properties of the LaCoO3 ceramic synthesized via a solid-state reaction. A rhombohedral crystal structure with the R3̄c space group was revealed through Rietveld refinement of the XRD data. XPS analysis further confirmed the presence of multiple oxidation states of Co, and the mechanism of charge transport involving these multivalent cations was described using the small polaron hopping model. The La deficiency and Sr-substitution were found to increase the electrical conductivity in the LCO1 and LCO2 compositions, which resulted in a significant increase in the thermoelectric power factor. It was found that the increase in electrical conductivity of LCO1 and LCO2 was caused by a substantial reduction in the activation energy barrier for small polaron hopping conduction and an increase in fractional polaron concentration. The maximum power factor value of 78 µW m-1 K-2 was observed for the LCO2 composition at 403 K.

Genome survey sequencing-based SSR marker development and their validation in Dendrocalamus longispathus.

Bamboo is an important genetic resource in India, supporting rural livelihood and industries. Unfortunately, most Indian bamboo taxa are devoid of basic genomic or marker information required to comprehend the genetic processes for further conservation and management. In this study, we perform genome survey sequencing for development of de novo genomic SSRs in Dendrocalamus longispathus, a socioeconomically important bamboo species of northeast India. Using Illumina platform, 69.49 million raw reads were generated and assembled into 1,145,321 contig with GC content 43% and N50 1228 bp. In total, 46,984 microsatellite repeats were mined-out wherein di-nucleotide repeats were most abundant (54.71%) followed by mono- (31.91%) and tri-repeats (9.85%). Overall, AT-rich repeats were predominant in the genome, but GC-rich motifs were more frequent in tri-repeats. Afterwards, 21,596 SSR loci were successfully tagged with the primer pairs, and a subset of 50 were validated through polymerase chain reaction amplification. Of these, 36 SSR loci were successfully amplified, and 16 demonstrated polymorphism. Using 13 polymorphic SSRs, a moderate level of gene diversity (He = 0.480; Ar = 3.52) was recorded in the analysed populations of D. longispathus. Despite the high gene flow (Nm = 4.928) and low genetic differentiation (FST = 0.119), severe inbreeding (FIS = 0.407) was detected. Further, genetic clustering and STRUCTURE analysis revealed that the entire genetic variability is captured under two major gene pools. Conclusively, we present a comprehensive set of novel SSR markers in D. longispathus as well as other taxa of tropical woody bamboos.