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PublicationReview Genetic modification of crop plants with ribosome-inactivating protein genes for enhanced resistance to pathogens and pests(Springer Science and Business Media Deutschland GmbH, 2023) Rajesh Kumar; Shalini Srivastava; Vivek PrasadGenetic engineering has emerged as an attractive strategy for incorporating resistance in plants against diverse pathogens and has been largely achieved through transgenic expression of ribosome-inactivating proteins (RIPs), pathogenesis-related (PR) proteins, pathogen-derived genes, or strategies involving RNA interference and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) gene editing tool. RIPs are rRNA N-glycosylases that commonly exert their protective effects through suppression of translation by enzymatically inactivating ribosomes, thereby arresting protein synthesis. Additionally, a few RIPs may possess other enzymatic activities viz. superoxide dismutase, chitinase, DNase and phosphatase, contributing towards pathogen resistance in plants. RIPs are mostly produced by plants and conventionally classified into three types. Type I RIPs are monomeric, with catalytic A chains, exhibiting rRNA N-glycosylase activity. Type II RIPs are dimeric, comprising the enzymatically active A chain associated with the lectin B chain enabling an access inside the cells, hence these are often highly toxic. Less common Type III RIPs include the jasmonic acid inducible protein such as JIP-60, with the catalytic domain becoming functional upon removal of an internal peptide segment and following cleavage of a C-terminal domain which resembles the eukaryotic initiation factor 4e. Unusual RIPs and RIP-related proteins, that cannot be grouped into the classical three types of RIPs, because of their difference in size, structure, or function, also exist. Several RIPs have been recombinantly expressed and demonstrated to possess catalytic activity. Plants carrying RIP transgenes exhibit resistance against viruses, fungi and insects. More often, such studies have been carried out using model systems comprising tobacco, potato or tomato, transformed via Agrobacterium tumefaciens, and employing the most widely used promoter such as CaMV 35S, to enable a high-level expression of the RIP gene. This review focuses on the recent developments in the recombinant DNA approach for the modification of crops with RIP genes to reduce the impact of pathogens and pests. © 2023, The Author(s), under exclusive licence to Deutsche Phytomedizinische Gesellschaft.PublicationArticle EFFECT OF HYDROGEN GAS CONTENT ON SHRINKAGE DEFECTS IN ALUMINIUM ALLOY CASTINGS.(1986) S.N. Tiwari; S.L. MalhotraCylindrical castings tapered at both ends were made without feeders in a series of Al-Cu and Al-Si alloys with varying hydrogen contents. Depending on composition, a certain volume of hydrogen gas was needed to counteract shrinkage defects and form uniformly distributed gas holes in the casting. The amount of gas needed showed a correlation with liquidus temperature.PublicationArticle Electron transfer in biologically important systems: Polycyclic aromatic hydrocarbons, DNA bases and free radicals(World Scientific Publishing Co. Pte Ltd, 2018) M.K. Tiwari; P.C. MishraOccurrence of electron transfer was studied for different combinations of polycyclic aromatic hydrocarbons (PAHs) and DNA bases as electron donors or acceptors and free radicals only as electron acceptors. Geometries of all the molecules and radicals were optimized in aqueous medium employing the polarizable continuum model. Single electron transfer (SET) and sequential proton loss electron transfer mechanisms were investigated employing Gibbs free energies of the appropriate neutral, anionic and cationic species. Barrier energies involved in these phenomena were calculated using the Marcus theory. The SET barrier energies were found to be linearly correlated with ΔE= (Electron affinities of acceptors - Ionization potentials of donors). SET barrier energies from the DNA bases to the PAHs follow the order Cy > Th ≈ Ad > Gu, whereas SET barrier energies from the PAHs to the DNA bases follow the order Gu > Ad > Th ≈ Cy. Thus, guanine, among the DNA bases, is the best electron donor to the PAHs and worst electron acceptor from the same. © 2018 World Scientific Publishing Company.PublicationBook Chapter Phillips’s points and Padmapāda’s possible defense(Taylor and Francis, 2024) Nirmalya GuhaIn an article entitled “Padmapāda’s Illusion Argument,” Prof. Stephen Phillips argues that Padmapāda failed to show the possibility of his views about the absolute (brahman) through his illusion argument. Phillips, like many other philosophers, criticized the arguments Padmapāda presented in his Pañca-pādikā. This chapter will try to extract Padmapāda’s arguments from his writings and address the issues raised by Phillips. Although those arguments originated in the writings of Padmapāda, they have their own lives. They evolved through various other commentarial and independent philosophical works. The fundamental and subtle questions or issues Phillips has raised may not find answers in Pañca-pādikā. But one may address those issues by using the ideas which Phillips calls “Padmapāda’s arguments.” © 2024 selection and editorial matter, Malcolm Keating and Matthew R. Dasti; individual chapters, the contributors.PublicationBook Chapter Influence of Heavy Metal on Food Security: Recent Advances(Springer Singapore, 2020) Osikemekha Anthony Anani; Raghvendra Raman Mishra; Pragya Mishra; John Ovie Olomukoro; Tunde Ohiokhioya Thaddeus Imoobe; Charles Oluwaseun AdetunjiFood safety has been identified as one of the highly placed sustainable goals because of its relevance to the sustainability and well-being of mankind. Over the years human being is faced with several adverse effects that normally result in uncountable impairment in their health. This might be linked to the high level of contamination and environmental pollution as a result of heavy metal due to various anthropogenic activities as well as several agricultural and environmental activities. It has been observed that heavy metal can affect human metabolomics which normally results in a high level of morbidity in several countries most especially in developing countries. Therefore, this review intends to discuss extensively the influence of heavy metal contamination on mankind health and their eventual safety. Special emphasis was also laid on the influence of heavy metal on food contamination as a result of environmental and agricultural activities through the application of pesticides which normally lead to a high level of adsorption and accumulation of these toxic metal elements. Also, this chapter also elucidates the modes of action through various molecular and physiological translocation leads to the movement of these toxic metals into food crops. On the whole, several sustainable preventive and management strategies were proposed on how sustainability could be maintained in soil-food subsystems. © Springer Nature Singapore Pte Ltd. 2020.PublicationArticle Systemic resistance in chilli pepper against anthracnose (Caused by colletotrichum truncatum) induced by trichoderma harzianum, trichoderma asperellum and paenibacillus dendritiformis(MDPI AG, 2021) Mukesh Yadav; Manish Kumar Dubey; Ram Sanmukh UpadhyayIn the present study, Paenibacillus dendritiformis, Trichoderma harzianum, and Trichoderma asperellum were appraised as potential biocontrol agents that induce resistance in chilli (Capsicum annuum) against the devastating pathogen Colletotrichum truncatum, which causes anthracnose. Bright-field and scanning electron micrographs showed the hyphal degradation, lysis, and abnormal swelling in C. truncatum against P. dendritiformis in a dual plate assay. Under greenhouse conditions, chilli seeds pretreated with P. dendritiformis, T. asperellum, T. harzianum, and T. asperellum + T. harzianum by soil soak method inflicted an induced systemic resistance (ISR) in chilli against a C. truncatum-challenged condition. In chilli, the disease index percentage was significantly reduced in the T. asperellum + T. harzianum-treated seeds, followed by the T. harzianum-, T. asperellum-, and P. dendritiformis-treated seeds as compared to the untreated and challenged, respectively. Chilli seeds were primed with T. asperellum + T. harzianum (78.67%), which revealed maximum disease protection under the challenged condition, followed by T. harzianum (70%), T. asperellum (64%), and P. dendritiformis (56%) as compared to untreated and C. truncatum-challenged (6%) condition served as control. The seeds that were pretreated with biocontrol agents (BCAs) inflicted ISR against C. truncatum by enhancing the activity of defence-related enzymes (superoxide dismutase (SOD), peroxidase (POX), polyphenol oxidase (PPO), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and phenylalanine ammonia-lyase (PAL)), accumulating phenolic compounds, and increasing the relative chlorophyll content in chilli. Nitroblue tetrazolium (NBT) and 3,3′-Diaminobenzidine (DAB) stains were used to detect the accumulation of superoxide anion and hydrogen peroxide that appeared nearby the fungal infection sites. The accumulation of reactive oxygen species (O2− and H2O2 ) in the pathogen-inoculated leaves was a maximum of 48 hpi, followed by P. dendritiformis, T. asperellum, T. harzianum, and T. asperellum + T. harzianum treated tissue upon C. truncatum-challenged condition as compared to the control. Overall, our results showed the potential of T. harzianum, T. asperellum, and P. dendritiformis as biocontrol agents that prevent infection by C. truncatum and inflict an induced systemic resistance in chilli by enhancing the biosynthesis of phenolic compounds, defence and antioxidative enzymes, and reducing the lesion development and reactive oxygen species accumulation. This is the first report of induced systemic resistance against anthracnose in chilli obtained by application of T. harzianum, T. asperellum and P. dendritiformis, through seed priming. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.PublicationReview A Comparative Study on Calibration Approach Based Estimators for Domain Estimation Utilizing Power Function: Revisited(Springer Science and Business Media Deutschland GmbH, 2023) Ashutosh; Piyush Kant Rai; Ajeet Kumar SinghThe calibration approach based estimators of the domain mean have growing demand during past couple of decades. Estimation of domains is another challenging task for surveyors and several efforts have been made to produce the reliable estimators for this purpose. Prominently the power function based estimators in the sample surveys are having dual advantages for the selection and their application to produce an improved estimation at any stage in the terms of efficiency without much complexity. In the domain estimation utilization of the power function in the development of calibration based estimators are also very promising and provide considerable results. A simulation study has examined for the comparison of several calibration estimators along with the proposed estimator in terms of the absolute relative bias and simulated relative standard error. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.PublicationBook Chapter Monitoring changes in urban cover using landsat satellite images and demographical information(IGI Global, 2016) Prashant K. Srivastava; Swati Suman; Smita PandeyThe monitoring of urban cover is very important for the planner, management, governmental and non-governmental organizations for optimizing the use of urban resources and minimizing the environmental losses. The study here aims at analyzing the changes that occurred in urban green cover over a time span of 1991-2001 using multi-date Landsat satellite images data over the Varanasi district, India and its relation to demographical changes. The Support Vector Machines (SVMs) classifier has been used for image classification. The urbanization indicators such as Land Consumption Ratio (LCR) and Land Absorption Coefficient (LAC) were also used in order to understand the changes in urban cover and population dynamics. All the analysis indicates significant changes in the urban cover values with increasing population at both spatial and temporal scale.PublicationArticle Potentiality of Azolla as a suitable P-biofertilizer under salinity through acid phosphatase activity(2010) Satya Shila Singh; Arun Kumar Mishra; Ram Sanmukh UpadhyayThe cellular and extracellular acid phosphatase (APase, Electrical Conductivity (EC) 3.1.3.2) activities in different Azolla spp. were induced in P-deprived condition after 48 h and maximum was on the 12th day of incubation. APase activity has been investigated at different levels of NaCl. Highest cellular and extracellular APase activities were observed in A. microphylla at 20 (2-fold of the control) and 30 mM (3.2-fold of the control) NaCl, respectively, while lowest were in A. filiculoides. Presence of different concentrations of micro- and macronutrients in saline medium regulated the APase activity of the Azolla. Ca2+ played a major role in enhancing the APase activity under salinity. Heavy metals did not affect APase activity at the lower level, whereas its higher level inhibited the activity. The enhancement in the APase activity under moderate salinity suggests the major contribution of APase activity during salt-responsive physiological adaptation of Azolla possibly by providing maximum inorganic phosphate to the association, which might be helpful in compensating for the energy crisis caused by salt-induced inhibition in photosynthetic machinery and also in regulating the nutrient imbalances during salt shock or process of adaptation towards heavily polluted agricultural land. © 2010 Elsevier B.V. All rights reserved.PublicationArticle Genome-wide association mapping reveals key genomic regions for physiological and yield-related traits under salinity stress in wheat (Triticum aestivum L.)(Academic Press Inc., 2021) Shiksha Chaurasia; Amit Kumar Singh; Arvind Kumar; L.S. Songachan; Mahesh C. Yadav; Sundeep Kumar; Jyoti Kumari; Ruchi Bansal; Parbodh Chander Sharma; Kuldeep SinghA genome-wide association study (GWAS) was conducted using six different multi-locus GWAS models and 35K SNP array to demarcate genomic regions underlying reproductive stage salinity tolerance. Marker-trait association analysis was performed for salt tolerance indices (STI) of 11 morpho-physiological traits, and the actual concentrations of Na+ and K+, and the Na+/K+ ratio in flag leaf. A total of 293 significantly associated quantitative trait nucleotides (QTNs) for 14 morpho-physiological traits were identified. Of these 293 QTNs, 12 major QTNs with R2 ≥ 10.0% were detected in three or more GWAS models. Novel major QTNs were identified for plant height, number of effective tillers, biomass, grain yield, thousand grain weight, Na+ and K+ content, and the Na+/K+ ratio in flag leaf. Moreover, 48 candidate genes were identified from the associated genomic regions. The QTNs identified in this study could potentially be targeted for improving salinity tolerance in wheat. © 2021 Elsevier Inc.