Inhibitory Effect of Cow Urine against Colletotrichum capsici Isolated from Anthracnose of Chilli (Capsicum annuum L.)

Cow urine has got several applications in agriculture. It is shown to possess inhibitory activity against many phytopathogenic fungi and bacteria. Among various diseases of Chilli, anthracnose is the most important disease which results in drastic reduction in yield. The present study was conducted with an aim to determine antifungal efficacy of cow urine against Colletotrichum capsici isolated from anthracnose of chilli (Capsicum annuum L.). Poisoned food technique was employed to determine antifungal activity of different concentrations of cow urine (5, 10 and 15%). Cow urine was found to display concentration dependent inhibitory activity against fungal growth. An inhibition of >50% was observed at 5% concentration. In conclusion, the use of cow urine can be the costeffective and eco-friendly approach for controlling anthracnose in chilli

Antimicrobial Activity of Ramalina conduplicans Vain. (Ramalinaceae)

The members of the genus Ramalina (Ramalinaceae) are fruticose lichens growing on various types of substrata. The present study was conducted with an aim of determining antimicrobial activity of Ramalina conduplicans Vain. The powdered lichen material was extracted sequentially using petroleum ether, ethyl acetate and ethanol. The solvent extracts were screened for antibacterial activity by Agar well diffusion assay against 15 bacteria which included reference strains and isolates from burn, dental caries and urinary tract infections. Poisoned food technique was performed to determine antifungal effect of solvent extracts against fungal isolates from anthracnose of chilli, foot rot of finger millet and mouldy grains of sorghum. Usnic acid, Salazinic acid and Sekikaic acid were detected in the lichen. The solvent extracts were shown to exhibit dose dependent inhibitory activity against test bacteria. Ethyl acetate extract inhibited reference bacterial strains to higher extent. Among solvent extracts, only ethanol extract inhibited all urinary tract bacteria. S. aureus isolates from burn were inhibited to higher extent when compared to S. mutans isolates from dental caries. The solvent extracts exhibited varied inhibitory activity against test fungi. Ethyl acetate extract inhibited Alternaria sp., Aspergillus flavus and Sclerotium rolfsii to higher extent while Colletotrichum capsici and Helminthosporium sp. were inhibited to higher extent by petroleum ether and ethanol extract respectively. The observed inhibitory potential of solvent extracts of R. conduplicans could be ascribed to the presence of secondary metabolites. The lichen can be used in the treatment of bacterial infections and to manage plant pathogenic fungi.Keywords: i Antimicrobial Agar well diffusion Poisoned food techniqu

Inhibitory Activity of Polyalthia longifolia, Anaphalis lawii and Gnidia glauca against Colletotrichum capsici and Urinary Tract Pathogens

The present study was conducted with an aim of determining inhibitory effect of extracts from different parts of Polyalthia longifolia (leaf, ripe and unripe pericarp), Anaphalis lawii (leaf and flower), Gnidia glauca (leaf, bark and flower) against Colletotrichum capsici and urinary tract pathogens. The shade dried plant materials were extracted using methanol. Antifungal effect of extracts was evaluated against Colletotrichum capsici isolated from anthracnose of chilli by Poisoned food technique. Antibacterial activity of extracts was determined against five antibiotic resistant bacteria isolated from urinary tract infections by Agar well diffusion assay. The extracts caused marked inhibition of mycelial growth of C. capsici as indicated by reduced diameter of fungal colonies on poisoned plates. Extracts of P. longifolia inhibited C. capsici to higher extent followed by A. lawii and G. glauca. All extracts from selected plants inhibited test bacteria but to varied extent. Susceptibility was higher in case of Gram positive when compared to Gram negative bacteria. Staphylococcus aureus and Escherichia coli were inhibited to higher extent among Gram positive and Gram negative bacteria respectively. Among plants, P. longifolia caused higher inhibition of test bacteria. The extracts from the selected plants can be considered as promising sources of bioactive agents which can be used to treat urinary tract infections caused by antibiotic resistant bacteria and to control anthracnose of chilli. Further studies are to be carried in order to isolate and characterize bioactive principles from extracts and to determine their inhibitory potential against C. capsici and uropathogens

Search for Light Dark Matter with NA64 at CERN

Thermal dark matter models with particle χ masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV χ production through the interaction mediated by a new vector boson, called the dark photon A′, in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With 9.37×1011 electrons on target collected during 2016–2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the A′ couplings to photons for masses mA′≲0.35  GeV, and to exclude scalar and Majorana dark matter with the χ-A′ coupling αD≤0.1 for masses 0.001≲mχ≲0.1  GeV and 3mχ≤mA′.Thermal dark matter models with particle $\chi$ masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV $\chi$ production through the interaction mediated by a new vector boson, called the dark photon $A'$, in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With $9.37\times10^{11}$ electrons on target collected during 2016-2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the $A'$ couplings to photons for masses $m_{A'} \lesssim 0.35$ GeV, and to exclude scalar and Majorana dark matter with the $\chi-A'$ coupling $\alpha_D \leq 0.1$ for masses $0.001 \lesssim m_\chi \lesssim 0.1$ GeV and $3m_\chi \leq m_{A'}$

Probing Light Dark Matter with positron beams at NA64

We present the results of a missing-energy search for Light Dark Matter which has a new interaction with ordinary matter transmitted by a vector boson, called dark photon ($A^\prime$). For the first time, this search is performed with a positron beam by using the significantly enhanced production of $A^\prime$ in the resonant annihilation of positrons with atomic electrons of the target nuclei, followed by the invisible decay of $A^\prime$ into dark matter. No events were found in the signal region with $(10.1 \pm 0.1)~\times~10^{9}$ positrons on target with 100 GeV energy. This allowed us to set new exclusion limits that, relative to the collected statistics, prove the power of this experimental technique. This measurement is a crucial first step toward a future exploration program with positron beams, whose estimated sensitivity is here presented.We present the results of a missing-energy search for Light Dark Matter which has a new interaction with ordinary matter transmitted by a vector boson, called dark photon $A^\prime$. For the first time, this search is performed with a positron beam by using the significantly enhanced production of $A^\prime$ in the resonant annihilation of positrons with atomic electrons of the target nuclei, followed by the invisible decay of $A^\prime$ into dark matter. No events were found in the signal region with $(10.1 \pm 0.1)~\times~10^{9}$ positrons on target with 100 GeV energy. This allowed us to set new exclusion limits that, relative to the collected statistics, prove the power of this experimental technique. This measurement is a crucial first step toward a future exploration program with positron beams, whose estimated sensitivity is here presented

Measurement of the intrinsic hadronic contamination in the NA64<math altimg="si2.svg" display="inline" id="d1e670"><mrow><mo>−</mo><mi>e</mi></mrow></math> high-purity <math altimg="si3.svg" display="inline" id="d1e678"><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>/</mo><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> beam at CERN

In this study, we present the measurement of the intrinsic hadronic contamination at the CERN SPS H4 beamline configured to transport electrons and positrons at 100 GeV/c momentum. The analysis was performed using data collected by the NA64-$e$ experiment in 2022. Our study is based on calorimetric measurements, exploiting the different interaction mechanisms of electrons and hadrons in the NA64-ECAL and NA64-HCAL detectors. We determined the intrinsic hadronic contamination by comparing the results obtained using the nominal electron/positron beamline configuration with those obtained in a dedicated setup, in which only hadrons impinged on the detector. The significant differences in the experimental signatures of electrons and hadrons motivated our approach, resulting in a small and well-controlled systematic uncertainty for the measurement. Our study allowed us to precisely determine the intrinsic hadronic contamination, which represents a crucial parameter for the NA64 experiment in which the hadron contaminants may result in non-trivial backgrounds. Moreover, we performed dedicated Monte Carlo simulations for the hadron production induced by the primary T2 target. We found a good agreement between measurements and simulation results, confirming the validity of the applied methodology and our evaluation of the intrinsic hadronic contamination.We present the measurement of the intrinsic hadronic contamination at the CERN SPS H4 beamline configured to transport electrons and positrons at 100 GeV/c. The analysis, performed using data collected by the NA64-e experiment in 2022, is based on calorimetric measurements, exploiting the different interaction mechanisms of electrons and hadrons in the NA64 detector. We determined the contamination by comparing the results obtained using the nominal electron/positron beamline configuration with those from a dedicated setup, in which only hadrons impinged on the detector. We also obtained an estimate of the relative protons, anti-protons and pions yield by exploiting the different absorption probabilities of these particles in matter. We cross-checked our results with a dedicated Monte Carlo simulation for the hadron production at the primary T2 target, finding a good agreement with the experimental measurements.In this study, we present the measurement of the intrinsic hadronic contamination at the CERN SPS H4 beamline configured to transport electrons and positrons at 100 GeV/c momentum. The analysis was performed using data collected by the NA64-$e$ experiment in 2022. Our study is based on calorimetric measurements, exploiting the different interaction mechanisms of electrons and hadrons in the NA64-ECAL and NA64-HCAL detectors. We determined the intrinsic hadronic contamination by comparing the results obtained using the nominal electron/positron beamline configuration with those obtained in a dedicated setup, in which only hadrons impinged on the detector. The significant differences in the experimental signatures of electrons and hadrons motivated our approach, resulting in a small and well-controlled systematic uncertainty for the measurement. Our study allowed us to precisely determine the intrinsic hadronic contamination, which represents a crucial parameter for the NA64 experiment in which the hadron contaminants may result in non-trivial backgrounds. Moreover, we performed dedicated Monte Carlo simulations for the hadron production induced by the primary T2 target. We found a good agreement between measurements and simulation results, confirming the validity of the applied methodology and our evaluation of the intrinsic hadronic contamination