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Barley (Hordeum vulgare L.) is a major cereal grain and is known as a halophyte (a halophyte is a salt-tolerant plant that grows in soil or waters of high salinity). We therefore conducted a pot experiment to explore plant growth and biomass, photosynthetic pigments, gas exchange attributes, stomatal properties, oxidative stress and antioxidant response and their associated gene expression and absorption of ions in H. Vulgare. The soil used for this analysis was artificially spiked at different salinity concentrations (0, 50, 100 and 150 mM) and different levels of ascorbic acid (AsA) were supplied to plants (0, 30 and 60 mM) shortly after germination of the seed. The results of the present study showed that plant growth and biomass, photosynthetic pigments, gas exchange parameters, stomatal properties and ion uptake were significantly (p < 0.05) reduced by salinity stress, whereas oxidative stress was induced in plants by generating the concentration of reactive oxygen species (ROS) in plant cells/tissues compared to plants grown in the control treatment. Initially, the activity of antioxidant enzymes and relative gene expression increased to a saline level of 100 mM, and then decreased significantly (P < 0.05) by increasing the saline level (150 mM) in the soil compared to plants grown at 0 mM of salinity. We also elucidated that negative impact of salt stress in H. vulgare plants can overcome by the exogenous application of AsA, which not only increased morpho-physiological traits but decreased oxidative stress in the plants by increasing activities of enzymatic antioxidants. We have also explained the negative effect of salt stress on H. vulgare can decrease by exogenous application of AsA, which not only improved morpho-physiological characteristics, ions accumulation in the roots and shoots of the plants, but decreased oxidative stress in plants by increasing antioxidant compounds (enzymatic and non-enzymatic). Taken together, recognizing AsA's role in nutrient uptake introduces new possibilities for agricultural use of this compound and provides a valuable basis for improving plant tolerance and adaptability to potential salinity stress adjustment. [ABSTRACT FROM AUTHOR]

Diaphorina citri Kuwayama (Hemiptera: Liviidae) is one of the devastating pests of citrus orchards in different regions of the world and its management depends upon the use of insecticides. The work was conducted to evaluate the toxicities and resistance levels to various insecticides in a field collected population of citrus psylla from an area of Pakistan. The field population was also kept under selection pressure with thiamethoxam for several generations to study the impact of selection on thiamethoxam resistance development. The resistant population was then studied for cross-resistance with insecticides from different groups and realized heritability of thiamethoxam resistance was determined to assess the potential of resistance development. Selection of D. citri from G 1 -G 7 with thiamethoxam produced 229-fold resistant strain in the laboratory. Selected strain exhibited very low cross-resistance with flonicamid, buprofezin, and spirotetramat; low cross-resistance with diafenthiuron and fenpropathrin, moderate cross-resistance with nitenpyram and pyriproxyfen, and a very high cross-resistance with acephate and methomyl. The estimated realized heritability of thiamethoxam resistance was 0.36. This study provides information on the impact of selection on resistance development and its management by restoring the susceptibility of D. citri through rotation of insecticides with low level of cross-resistance. • Selection of D. citri from G 1 -G 7 with thiamethoxam produced 229-fold resistant strain in the laboratory. • Selection induced very high cross-reistance with acephate and methomyl. • Moderate cross-reistance with nitenpyram and pyriproxyfen was observed. • The estimated realized heritability of thiamethoxam resistance was 0.36. • The number of generations predicted for 10-fold increase in thiamethoxam resistance would be 4.16. [ABSTRACT FROM AUTHOR]

Phosphate solubilizing bacteria (PSB) have the ability to solubilize insoluble phosphorus to make it available for plant roots to be absorbed. In this study, isolation of rhizobacteria and screening of their ability for phosphate solubilization, production of indole acetic acid (IAA), antagonistic activity against fungal pathogen and intrinsic antibiotic resistance was studied. In total, 15 isolates of PSB were found gram negative with rod shaped cells. Different levels of antibiotic resistance was seen against four antibiotics (Ampicillin, Kanamycin, Tetracycline and Streptomycin 25, 30, 30 and 10 μg/ml respectively) by Rhizobacterial isolates (Seven isolates were found to show antifungal activity against Fusarium oxysporum ). All PSB isolates were found to solubilize insoluble phosphorous Ca 3 (PO 4 ) and produce IAA. Two PSB isolates sequences were found novel and were submitted in NCBI database. Conclusively, combine application of rhizobacterial isolates, Sugarcane (SC-22) in addition with antifungal agent can prove to be an excellent combination to solubilize insoluble phosphorus and to act as antifungal remedy. Further this combination can be eco-friendly and prove to be cost effective strategy to improve crop production. [ABSTRACT FROM AUTHOR]

Heavy metal remediation, such as cadmium (Cd2+) by microbial strains is efficient and environment-friendly. In this current study, we exploited the potential of Bacillus strains (Cd2+-tolerant; NMTD17, GBSW22, and LLTC96) to regulate Cd2+ biosorption mechanisms and improve rice seedling growth. The results showed that initial concentration and contact time affected Cd2+ biosorption, and the kinetic models of pseudo orders were effective in the elaborate biosorption process. Mainly, the bacterial cell wall had the potential for Cd2+ biosorption, and we found non-significant biosorption alterations among bacterial strains' inner and outer surfaces of cell membranes. Furthermore, the Fourier transform infrared (FTIR) spectroscopy analysis identified the differences in functional groups, such as C–N, PO 2 , –SO 3 , C O, COOH, C–O, C–N, –OH, and –NH that interact in biosorption by Bacillus strains. The scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) examination revealed that the binding of Cd2+ to microbes was mostly based on ion exchange pathways. Moreover, the Bacillus strains responded to Cd2+ stress in rice under pot experiment at various concentrations (0, 0.25, and 0.50 mg kg−1), and they also influenced the chlorophyll contents and antioxidants activities were studied. The analysis of physio-morphological parameters was observed to be increased, which indicated that all Bacillus strains showed significant effects on rice growth under Cd2+ stress. These results revealed that the selected strains had the capability for additional use in the development of Cd2+ bioremediation methods. These strains also provided plant growth-promoting (PGP) traits that can alleviate the harmful effects of Cd2+ in rice plants. [Display omitted] • Bacillus sp. increased adsorption of Cd2+ on the cell wall. • Lterations in functional groups that were involved in Bacillus -Cd2+ biosorption. • Bacillus microbial strains increased Cd2+ immobilization in soil. • Microbial strains reduced Cd2+ content and improved plant growth. • Suitable microbial species that may be modified to enhance Cd2+ biosorption. [ABSTRACT FROM AUTHOR]

Phytopathogenic bacteria cause severe economic losses in agricultural production worldwide. The spread rates, severity, and emerging plant bacterial diseases have become serious threat to the sustainability of food sources and the fruit industry. Detection and diagnosis of plant diseases are imperative in order to manage plant diseases in field conditions, greenhouses, and food storage conditions as well as to maximize agricultural productivity and sustainability. To date, various techniques including, serological, observation-based, and molecular methods have been employed for plant disease detection. These methods are sensitive and specific for genetic identification of bacteria. However, these methods are specific for genetic identification of bacteria. Currently, the innovative biosensor-based disease detection technique is an attractive and promising alternative. A biosensor system involves biological recognition and transducer active receptors based on sensors used in plant-bacteria diagnosis. This system has been broadly used for the rapid diagnosis of plant bacterial pathogens. In the present review, we have discussed the conventional methods of bacterial-disease detection, however, the present review mainly focuses on the applications of different biosensor-based techniques along with point-of-care (POC), robotics, and cell phone-based systems. In addition, we have also discussed the challenges and limitations of these techniques. [Display omitted] • Early detection of a disease is essential to prevent crop loss. • The conventional techniques are sensitive and specific for pathogenic identification. • Biosensor-based techniques are innovative and promising alternatives. • Biosensor-based systems are attractive and efficient for early detection of pathogen. [ABSTRACT FROM AUTHOR]

Silicon (Si), a major contributing constituent for plant resistance against abiotic stresses. In spite of this, the detailed mechanisms underlying the potential of Si in mitigating salt toxicity in maize (Zea mays L.) are still poorly understood. The present study deals with the response of Si application on growth, gaseous exchange, ion homeostasis and antioxidant enzyme activities in two maize cultivars (P1574 and Hycorn 11) grown under saline conditions. Salt stress remarkably reduced the plant tissue (roots and shoots) biomass, relative water contents (RWC), membrane stability index (MSI), gaseous exchange characteristics, and antioxidant enzymatic activities i.e., superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and catalase (CAT). However, salt-induced phytotoxicity increased the plant tissue concentration of malondialdehyde (MDA), hydrogen peroxide (H 2 O 2), Na+/K+ ionic ratio, Na+ translocation (root to shoot), and its uptake. The detrimental effects were more prominent in Hycorn 11 cultivar than the P1574 cultivar at higher salinity level (S2; 160 mM NaCl). The addition of Si alleviated salt toxicity, which was more obvious in P1574 relative to Hycorn 11 as demonstrated by an increasing trend in RWC, MSI, and activities of SOD, POD, APX and CAT. Besides, Si-induced mitigation of salt stress was due to the depreciation in Na+/K+ ratio, Na+ ion uptake at the surface of maize roots, translocation in plant tissues and thereby significantly reduced Na+ ion accumulation. The findings showed a new dimension regarding the beneficial role of Si in maize plants grown under salt toxicity. • Salt stress reduced maize growth, increased oxidative stress and sodium uptake by plants. • Silicon (Si) supply increased plant biomass through alleviating salt-induced phytotoxicity. • Silicon decreased Na+/K+ ratio in plants under salt stress • Silicon reduced sodium uptake, translocation and bioaccumulation by plants. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) that increasingly emanating from natural and human activity sources are invisible pollutants and the presence of even minute amounts of these substances makes them undesirable due to their negative attributes. The PAHs extraction and removal from effluents are major steps for analysis and removal. Chemical, biological and physical approaches are used for the removal of PAHs from wastewater. However, some of these techniques have toxic by-products. Currently, physical approaches such as liquid-liquid solvent extraction, filtration, and adsorption appear to be the best methods due to their safety, affordability, universal nature and ease of operation. However, some of the materials used in the currently available physical methods face the challenges of fouling, low recovery, their relatively long extraction time and high usage of toxic solvent. To overcome these limitations, and for the cleaner production of water, the incorporation of carbon nanotubes (CNTs) into existing physical procedures without distorting their existing structural architectures is proposed. CNTs are considered because hydrophobic hollow pores of CNTs absorb most aromatic pollutants while allowing the friction-free passage of water without consuming much energy. The functionalization of CNTs with various receptors and groups further permit the selective trapping of pollutants of interest. The ability of the proposed methods to cheaply and sustainably remove PAHs from contaminated water will make hitherto carcinogenic polluted water cleaner for public consumption. This comprehensive article presents an extensive literature review of CNTs and their use for various physical techniques. It further presents CNT as a central focus, with an in-depth critical analysis of the state-of-the-art trends of PAH removal using CNTs, current hurdles and future challenges, so that it could be used as a reference manual adding scientific value for developing any future methods for water purification and the removal of any aromatic pollutants. [ABSTRACT FROM AUTHOR]

The study was aimed to obtain baseline information about the presence and distribution of Peste des petits ruminants (PPR) in Pakistan by quantifying the sero-prevalence of this infection in all provinces/regions in the country. There are ongoing activities towards the progressive control and eventual eradication of PPR from Pakistan. To design a suitable control program and monitor its progress, baseline information on the occurrence of the disease in the target population is needed. Using a cluster sampling approach a total of 19575 serum samples from sheep and goat were collected from all provinces of the country. These samples were analyzed for the presence of antibodies against PPR virus using a competitive ELISA. Out of 19575 samples tested, 5389 were classified as sero-positive. The prevalence (95% confidence intervals (CI)) at the province level ranged 9.93% (0.027%–0.151%) in Azad Jammu & Kashmir to 38.16% (0.366%–0.466%) in Balochistan. Difference in sero-positivity could be attributed to animals’ movement, agro-climatic conditions of areas. Risk factors covered in the study were season as well as age and sex of the animals. PPR is endemic and it is distributed across all provinces in the country. This study provides basic information for the identification of disease hotspots for implementation of a control programme in Pakistan. [ABSTRACT FROM AUTHOR]

Over the past two decades, steroidal estrogens (SEs) such as 17α-ethylestradiol (EE2), 17β-estradiol (E2),17α-estradiol (17α-E2), estriol (E3) and estrone (E1) have elicited worldwide attention due to their potentially harmful effects on human health and aquatic organisms even at low concentration ng/L. Natural steroidal estrogens exhibit greater endocrine disruption potency due to their high binding effect on nuclear estrogen receptors (ER). However, less has been explored regarding their associated environmental risks and fate. A comprehensive bibliometric study of the current research status of SEs was conducted using the Web of Science to assess the development trends and current knowledge of SEs in the last two decades, from 2001 to 2021 October. The number of publications has tremendously increased from 2003 to 2021. We summarized the contamination status and the associated ecological risks of SEs in different environmental compartments. The results revealed that SEs are ubiquitous in surface waters and natural SEs are most studied. We further carried out an in-depth evaluation and synthesis of major research hotspots and the dominant SEs in the matrices were E1, 17β-E2, 17α-E2, E3 and EE2. Nonetheless, investigations of SEs in soils, groundwater, and sediments remain scarce. This study elucidates SEs distribution, toxicological risks, ecological fate and mitigation measures, which will be beneficial for future monitoring, management, and risk assessment. Further studies are recommended to assess the toxicological risks of different SEs in complex environmental matrices to pursue a more precise and holistic quantitative estimation of estrogenic risk. [Display omitted] • Distribution, occurrence and ecological risks of steroid estrogens are current research hotspots. • Recommendations are proposed to mitigate SEs contamination in the environment. • Attention should be paid to accumulation and impacts of SEs in food chains. • Half-lives and persistence of SEs is influenced by location and redox conditions. [ABSTRACT FROM AUTHOR]

A comparative genetic study of 23 field isolates and vaccine strains of Pasteurella multocida associated with haemorrhagic septicaemia cases from Pakistan and Thailand was done using pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The MLST sequence type (ST) for all 20 of the 23 isolates tested was 122. The PFGE results showed one band difference between the Pakistani and the Thai isolates. Sequence type 122 is the dominant associated profile with haemorrhagic septicaemia (HS) cases in South Asia. The study supports the concept of using PFGE for short-term epidemiology and MLST for long-term epidemiology. [ABSTRACT FROM AUTHOR]

Abstract: Pakistan is prone to seismic activity, and its capital, Islamabad, is located close to the Main Boundary Thrust (MBT) fault. On October 8th, 2005 the disastrous Muzaffarabad earthquake shook Islamabad and damaged many high-rise buildings. A probabilistic seismic hazard analysis technique was used to estimate strong ground motion parameters for a closely spaced 1km grid. Traditionally, PGA is calculated, which is then used in structural earthquake resistant design or seismic safety assessment. However, Peak Ground Acceleration (PGA) is not sufficient to design for seismic load or to account for the modern building code’s emphasis on the use of spectral acceleration values. Therefore, a seismic hazard analysis was performed for Islamabad, and the design parameters that are required by codes to account for seismic loading were derived. [Copyright &y& Elsevier]

Abstract: Peste des petits ruminants (PPR), is a highly contagious viral disease affecting domestic and wild small ruminants. It is in the list of animal diseases to be notified to the World Organization for Animal Health (Office International des Epizooties, OIE). Because of the high magnitude of importance of sheep and goats for the poor and landless farmers, the control of disease, which has a negative impact on their productions, is aimed at poverty alleviation. A single injection of live attenuated monovalent vaccine (Nig/75/1) can induce protective immunity for at least the economic life of the animals, however vaccine efficacy only holds if the vaccination is done before exposure and when the animals at sub-clinical level of infection. In Pakistan, though published reports on existence of PPR in the country are few but findings on clinical signs and course of the disease are consistent with the internationally published reports on PPR elsewhere and the neighboring countries. The limited reports of incidence of PPR from few places/provinces do not exclude the possibility of presence of infection in other parts/province of the country. Therefore, the epidemiology, pathogenicity, host susceptibility/resistance and molecular nature of PPR virus have become multifaceted than considered formerly. It is anticipated that patent PPR vaccines and sophisticated diagnostic tests that differentiate infected and vaccinated animals might improve the diagnostic and epidemiological capabilities. [Copyright &y& Elsevier]

Abstract: Peste des petits ruminants (PPR) is a highly contagious disease of domestic and wild small ruminants. Rapid, sensitive and specific laboratory assay is useful to enable timely implementation of appropriate control to restrict the spread of disease. The present study reports observations from 50 laboratory confirmed outbreaks of PPR and provides details of the presence or otherwise of PPR virus (PPRV) in 427 tissue/organ samples from small ruminants. Most of the samples used for the detection of PPR viral antigen were derived from all major regions within the country; however, these samples may not be a true representation of the target population still it provided a lot more information. Monoclonal antibody-based diagnostic kit manufactured by Biological Diagnostic Supplies Ltd., Flow Laboratories and Institute for Animal Health Pirbright, Surrey, England, were used for the detection of PPR viral antigen (immuno-capture ELISA). Findings suggested that the disease outbreaks were more severe in goats than sheep and the frequency of disease outbreaks was greater between the months of January to April as compared to other periods of the year and it was maximum in month of March (almost 33%). Based on the data of 50 outbreaks (427 samples), the prevalence of PPR in small ruminants in Pakistan was 40.98%. A greater number of positive cases were observed in the southern and northern parts of the country (30–60%) as compared to west and south-west (10–30%). These findings may be correlated with variations in the sheep and goat husbandry practices within different geographic regions and the topography of different areas. The study indicated the scenario of virus circulation in the population and prevalence in actual outbreaks situation, which may be kept in mind while deciding the vaccination strategy for the control of disease. [Copyright &y& Elsevier]