Browsing by Author "Shailendra Singh"

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Bio-protective microbial agents from rhizosphere eco-systems trigger plant defense responses provide protection against sheath blight disease in rice (Oryza sativa L.)
(Elsevier GmbH, 2016) Udai B. Singh; Deepti Malviya; Wasiullah; Shailendra Singh; Jatindra K. Pradhan; Bhanu P. Singh; Manish Roy; Mohd Imram; Neelam Pathak; B.M. Baisyal; Jai P. Rai; B.K. Sarma; Rajiv K. Singh; P.K. Sharma; Saman Deep Kaur; M.C. Manna; Sushil K. Sharma; Arun K. Sharma
Sheath blight of rice (Oryza sativa L.) caused by Rhizoctonia solani is a major disease and attempts are being made to develop microbe based technologies for biocontrol of this pathogen. However, the mechanisms of biocontrol are not fully understood and still require indepth study in the backdrop of emerging concepts in biological systems. The present investigation was aimed at deciphering the mechanisms of biocontrol of sheath blight of rice employing Pseudomonas fluorescens and Trichoderma harzianum as model agents for biocontrol. Initially 25, 5 and 5 strains of P. fluorescens, T. viride and T. harzianum, respectively, were screened for their biocontrol potential. Out of which, six strains with higher value of percent inhibition of fungal mycelium in dual plate assay were selected. The role of P. fluorescens, T. viride and T. harzianum were investigated in induction and bioaccumulation of natural antioxidants, defence-related biomolecules and other changes in plant which lead not only to growth promotion but also protection from pathogenic stress conditions in rice. The two most promising strains, P. fluorescens PF-08 and T. harzianum UBSTH-501 selected on the basis of in planta evaluation, when applied individually or in combination, significantly enhanced the accumulation of defence-related biomolecules, enzymes and exhibited biocontrol potential against R. solani. A modified/newly developed delivery system was applied for the first time in the experiments involving inoculation of plants with both bioagents, viz. P. fluorescens PF-08 and T. harzianum UBSTH-501. Results suggested that application of P. fluorescens PF-08 and T. harzianum UBSTH-501 alone or in combination, not only helps in control of the disease but also increases plant growth along with reduction in application of toxic chemical pesticides. © 2016 Elsevier GmbH
Chemical management of seed-borne diseases: Achievements and future challenges
(Springer Singapore, 2020) Udai B. Singh; Rajan Chaurasia; Nazia Manzar; Abhijeet S. Kashyap; Deepti Malviya; Shailendra Singh; Pooja Kannojia; P.K. Sharma; Imran Mohd.; A.K. Sharma
Seed is a basic and most important input for agriculture and high-quality seed is also required in international seed trading. There are many seed-borne diseases and pathogens that have negative impact on seed health and its quality. Seed-borne inoculums are the main source of primary infection leading to disease development. The disease gets established in the field wherever the infected seed is used and causes severe yield losses. Paul Neergaard is considered as father of seed pathology who has contributed a lot in the development of seed pathology. Seed-borne pathogenic microorganisms mainly fungi, viruses and bacteria are greatly affecting seed quality and cause diseases that affect seedling production in the nurseries. Management strategies for the control of various seed-borne diseases are mainly based on chemical seed treatment. Studies have been carried out with a view to find out the best way to use chemicals in seed production. Such studies are very few, and hence, there is a need to conduct further research so that new chemicals could be incorporated into seed-borne disease management programmes. We need to have additional ways to control diseases that are seed-borne, and chemical pesticides are effective against a wide spectrum of diseases. This chapter provides a brief review of seed-borne pathogen problems that affect seeds and discusses established and potential control practices by using chemicals like fungicides, insecticides or defence activators and further gives the future perspectives where focus should be given with respect to seed pathology and management of seed-borne disease. © Springer Nature Singapore Pte Ltd. 2020.
Compatible salt-tolerant rhizosphere microbe-mediated induction of phenylpropanoid cascade and induced systemic responses against Bipolaris sorokiniana (Sacc.) Shoemaker causing spot blotch disease in wheat (Triticum aestivum L.)
(Elsevier B.V., 2016) Udai B. Singh; Deepti Malviya; Wasiullah; Shailendra Singh; Mohd. Imran; Neelam Pathak; Manzar Alam; Jai P. Rai; Rajiv K. Singh; B.K. Sarma; P.K. Sharma; Arun K. Sharma
Cell wall is one of the first lines of defence used by plants to restrict invading fungal pathogens. Lignin is a complex polymer of hydroxylated and methoxylated phenylpropane units (monolignols). Cell wall lignification can establish mechanical barriers to pathogen invasion and renders the cell wall more resistant to pathogen attack. Compatible salt-tolerant rhizosphere microbe-mediated induction of phenylpropanoid cascade and induced systemic responses against Bipolaris sorokiniana (Sacc.) Shoemaker causing spot blotch disease in wheat (Triticum aestivum L.) is demonstrated and the details are being shared through this paper. Twelve rhizospheric microbial strains were tested against Bipolaris sorokiniana under in vitro condition on dual plate. Bacillus amyloliquefaciens B-16 and Trichoderma harzianum UBSTH-501 showed maximum inhibition of mycelial growth of B. sorokiniana and was used in further in planta assay. These selected antagonists were tested alone and in combination for induction of phenylpropanoid cascade in wheat infected with B. sorokiniana. Results showed that plants co-inoculated with B. amyloliquefaciens B-16 and T. harzianum UBSTH-501 up-regulated the phenylpropanoid cascade and manifold increase was recorded in phenylalanine ammonia lyase (PAL), peroxidase, chitinase and other enzymes related to induced systemic resistance. Results also showed that significantly higher amounts of phenolic acids viz. gallic acid, ferulic acid were accumulated in the plant leaves co-inoculated with B. amyloliquefaciens B-16 and T. harzianum UBSTH-501 as compared to individually inoculated and uninoculated control plants. Histopathological studies showed significantly higher cell wall lignification in plant leaves co-inoculated with B. amyloliquefaciens B-16 and T. harzianum UBSTH-501 than the plants under control. These results illustrate that microbe-mediated up-regulation of phenylpropanoid biosynthesis pathway is of critical importance for host defence against spot blotch pathogen invasion in wheat. © 2016 Elsevier B.V.
Drechslerella dactyloides and Dactylaria brochopaga mediated induction of defense related mediator molecules in tomato plants pre-challenged with Meloidogyne incognita
(Springer, 2019) Udai B. Singh; Shailendra Singh; Wasiullah Khan; Deepti Malviya; Pramod K. Sahu; Rajan Chaurasia; Sushil K. Sharma; A.K. Saxena
The present investigation was aimed to isolate and characterize the strains of Drechslerella dactyloides and Dactylaria brochopaga from decaying root galls of tomato in order to investigate their role in reprogramming of root apoplast that enhance defence responses in tomato pre-challenged with Meloidogyne incognita. Out of 23 strains of D. brochopaga and D. dactyloides were isolated from decaying root galls of tomato, three strains of D. dactyloides and five strains of D. brochopaga were found effective and these were selected for further characterization under controlled laboratory conditions. Further, D. dactyloides NDAd-05 and D. brochopaga NDDb-15 were found most promising strains for control of M. incognita. The study elucidates multifarious effects of D. dactyloides NDAd-05 and D. brochopaga NDDb-15 inoculated either individually or in combination on tomato plants pre-challenged with M. incognita under nethouse conditions. Results of this investigation revealed that inoculation of D. dactyloides NDAd-05 and D. brochopaga NDDb-15 increased various attributes in plants to significant degree conferring defence against M. incognita. Both the strains were found to have potential to enhance site-specific accumulation and activation of defence-related mediator molecules, enzymes and thus, exhibited biocontrol potential against M. incognita. Further, application of D. dactyloides NDAd-05 and D. brochopaga NDDb-15 not only assisted in the growth promotion but also activated phenylpropanoid pathway in root apoplast in addition to direct trapping of M. incognita. © 2019, Indian Phytopathological Society.
Drechslerella dactyloides and Dactylaria brochopaga mediated structural defense in tomato plants pre-challenged with Meloidogyne incognita
(Academic Press Inc., 2020) Udai B. Singh; Shailendra Singh; Deepti Malviya; Rajan Chaurasia; Pramod K. Sahu; Sushil K. Sharma; A.K. Saxena
The present study was undertaken with the objectives to study Drechslerella dactyloides NDAd-05 and Dactylaria brochopaga NDDb-15 mediated induction of structural defense responses leading to lower disease development and promoting growth in tomato pre-challenged with Meloidogyne incognita. The potential strains D. dactyloides NDAd-05 and D. brochopaga NDDb-15 were taken from Plant-Microbe Interaction and Rhizosphere Biology Lab, ICAR-National Bureau of Agriculturally Important Microorganisms, Kushmaur, Maunath Bhanjan, India. In vitro root colonization assay was performed using D. dactyloides NDAd-05 and D. brochopaga NDDb-15 in sand:soil culture (2:1) and significant tomato root colonization by NDAd-05 and NDDb-15 was recorded. The study elucidated multifarious effects of D. dactyloides NDAd-05 and D. brochopaga NDDb-15 when inoculated either individually or in combination in tomato plants pre-challenged with M. incognita. Additionally, D. dactyloides NDAd-05 and D. brochopaga NDDb-15 increased antioxidant as well as biocontrol activities significantly in tomato against M. incognita. Microscopic visualization of H2O2 and superoxide radicals in tomato leaves further corroborated the above findings. Further, inoculation of D. dactyloides NDAd-05 and D. brochopaga NDDb-15 activated the phenylpropanoid pathway in roots leading to increase cell wall lignifications and pectin deposition in tomato roots in addition to direct trapping and parasitizing of juveniles and adults of M. incognita. From the results it can be concluded that increased cell wall lignifications and pectin deposition probably restricted the entry of nematodes and ultimately decreased the M. incognita population in tomato roots. It was also observed that plants treated with bioagents individually or in combination modulated the phenotypical alterations and assisted plant growth promotion. This might be due to the interaction-dependent modulation of physio-biochemical pathways in the tomato plants which ultimately reduced the inoculum potential and disease intensity of M. incognita. © 2020 Elsevier Inc.
Earthworm grazed-trichoderma harzianum biofortified spent mushroom substrates modulate accumulation of natural antioxidants and bio-fortification of mineral nutrients in tomato
(Frontiers Media S.A., 2018) Udai B. Singh; Deepti Malviya; Wasiullah Khan; Shailendra Singh; N. Karthikeyan; Mohd. Imran; Jai P. Rai; B.K. Sarma; M.C. Manna; Rajan Chaurasia; Arun K. Sharma; Diby Paul; Jae-Wook Oh
The present investigation was aimed at evaluating the impact of earthworm grazed and Trichoderma harzianum biofortified spent mushroom substrate (SMS) on natural antioxidant and nutritional properties of tomato. Results of the investigation reveal that earthworm grazing and T. harzianum bio-fortification led to significant improvement in the physico-chemical properties of fresh SMS and its application increased the accumulation of natural antioxidants and mineral content in tomato as compared to either T. harzianum biofortified SMS or fresh SMS. In particular, the earthworm grazed, T. harzianum biofortified SMS (EGTHB-SMS) was found to inhibit lipid peroxidation and protein oxidation with significant increase in total polyphenol and flavonoid content in tomato. Further, it increased Fe2+/Fe3+ chelating activity, superoxide anion radical scavenging activity compared to other treatments. The results thus suggest an augmented elicitation of natural antioxidant properties in tomato treated with EGTHB-SMS, resulting in a higher radical scavenging activity, that is highly desirable for human health. In addition, the use of SMS to enhance the nutritional value of tomato fruits becomes an environment friendly approach in sustainable crop production. © 2018 Singh, Malviya, Khan, Singh, Karthikeyan, Imran, Rai, Sarma, Manna, Chaurasia, Sharma, Paul and Oh.
First report of Acanthochaetetes (Porifera: Demospongiae) from the Cretaceous Khalsi Formation, Ladakh Himalaya, India
(Cambridge University Press, 2021) Prasenjit Barman; Francisco Sánchez-Beristain; Shruti Ranjan Mishra; Mohd Ibrahim; Narendra Kumar Swami; Mukesh Bamniya; Shailendra Singh
The Cretaceous chaetetid sponge Acanthochaetetes huauclillensis Sánchez-Beristain and García-Barrera is reported for the first time from the Aptian-Cenomanian Khalsi Formation, Ladakh Himalaya, India. Its low-To high-domical growth form could suggest an adaptation to either an environment with constant sedimentation rates, or to an irregular substrate. However, these growth forms also may indicate an absence of important environmental/sedimentological changes during the lifespan of the sponges. In addition, the growth form of this species suggests a calm, non-Turbulent, reef-like microenvironment. Along with the other faunal assemblages, such as the rudists, corals, and the gastropod Nerinea, A. huauclillensis indicates a tropical to subtropical shallow marine carbonate platform setting. This new finding extends its stratigraphic range from the upper Hauterivian to the Aptian-Cenomanian interval in the eastern Tethyan realm. Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of The Paleontological Society.
Harnessing biocontrol potential of Trichoderma harzianum for control of Meloidogyne incognita in tomato
(Indian Phytopathological Society, 2017) Udai B. Singh; Shailendra Singh; Deepti Malviya; Rajan Chaurasia; Mohd. Imran; Jai P. Rai; Arun K. Sharma
The aim of the study was to evaluate the biocontrol potential of Trichoderma harzianum against Meloidogyne incognita and decipher mechanisms of induced systemic resistance and disease suppression in tomato grown in net house conditions. The fungal biocontrol agent T. harzianum UBSTH-501 was evaluated against M. incognita on dual plate under in vitro conditions and in planta under nethouse conditions. The results of in vitro parasitism on dual plates showed that T. harzianum causing infection on the eggs and juveniles of root-knot nematode, whereas, in planta assay showed that plants treated with talc based bioformulation T. harzianum UBSTH-501 exhibited manifold increase in the accumulation of total chlorophyll and enzymes, viz. chitinase, phenylalanine ammonia lyase (PAL) and peroxidase which is known to confer systemic resistance in tomato against M. incognita resulting into decreased nematode population and disease severity. Results revealed that T. harzianum UBSTH-501modulated phenylpropanoid pathways led to enhanced accumulation of defence related mediator molecules and enzymes in tomato resulted in disease suppression to a significant extents. © Indian Phytopathological Society 2017.
Integration of anti-penetrant tricyclazole, signaling molecule salicylic acid and root associated Pseudomonas fluorescens enhances suppression of Bipolaris sorokiniana in bread wheat (Triticum aestivum L.)
(Springer, 2019) Udai B. Singh; Shailendra Singh; Deepti Malviya; Nanjappan Karthikeyan; Mohd. Imran; Rajan Chaurasia; Manzar Alam; Pratap Singh; B.K. Sarma; Jai P. Rai; T. Damodaran; J.K. Tripathi; Sunil Kumar; Arun K. Sharma
Salicylic acid (SA) and root associated Pseudomonas fluorescens are known inducers of systemic resistance and influence plant defense responses including reprogramming of cellular mechanisms in response to biotic stress. However, integration of SA, tricyclazole and bioagent P. fluorescens in the integrated disease management practices is not clearly understood. With this rationale the present study was carried out to understand the effects of integration of an anti-penetrant tricyclazole, signaling molecule SA and P. fluorescens UBSPF-10 in modulation of defense cascades and enhancing suppression of Bipolaris sorokiniana in bread wheat (Triticum aestivum L.). Results showed that exogenous application of SA (100 mg L−1) alone and in combination with tricyclazole (750 mg L−1) and P. fluorescens UBSPF-10 significantly increased activation and accumulation of phenylalanine ammonia lyase (PAL), peroxidase, β 1,3-glucanase and chitinase activities in wheat leaves challenged with B. sorokiniana compared to individually treated and control plants. The influence of combined applications of SA, tricyclazole and P. fluorescens UBSPF-10 on lignin content in plant leaves was investigated and it was observed that the combined treatment resulted significant increase in the acid-soluble lignin content in wheat possibly leading to enhanced suppression of disease progression and severity. Furthermore, correlation analysis clearly indicated that enhanced accumulation of lignin in plant cells significantly reduces pathogen infection and invasion of tissue leading to reduction in disease development compared to other treatments. Therefore, it is concluded that combined application of SA, tricyclazole and P. fluorescens UBSPF-10 played an important role in suppression of B. sorokiniana development in wheat plants in a cooperative manner and thus, could be used in the integrated disease management practices of wheat. © 2019, Società Italiana di Patologia Vegetale (S.I.Pa.V.).
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
(Frontiers Media S.A., 2021) Pramod K. Sahu; Shailendra Singh; Udai B. Singh; Hillol Chakdar; Pawan K. Sharma; Birinchi K. Sarma; Basavaraj Teli; Raina Bajpai; Arpan Bhowmik; Harsh V. Singh; Anil K. Saxena
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. © Copyright © 2021 Sahu, Singh, Singh, Chakdar, Sharma, Sarma, Teli, Bajpai, Bhowmik, Singh and Saxena.
Lesson from ecotoxicity: Revisiting the microbial lipopeptides for the management of emerging diseases for crop protection
(MDPI AG, 2020) Deepti Malviya; Pramod Kumar Sahu; Udai B. Singh; Surinder Paul; Amrita Gupta; Abhay Raj Gupta; Shailendra Singh; Manoj Kumar; Diby Paul; Jai P. Rai; Harsh V. Singh; G.P. Brahmaprakash
Microorganisms area treasure in terms of theproduction of various bioactive compounds which are being explored in different arenas of applied sciences. In agriculture, microbes and their bioactive compounds are being utilized in growth promotion and health promotion withnutrient fortification and its acquisition. Exhaustive explorations are unraveling the vast diversity of microbialcompounds with their potential usage in solving multiferous problems incrop production. Lipopeptides are one of such microbial compounds which havestrong antimicrobial properties against different plant pathogens. These compounds are reported to be produced by bacteria, cyanobacteria, fungi, and few other microorganisms; however, genus Bacillus alone produces a majority of diverse lipopeptides. Lipopeptides are low molecular weight compounds which havemultiple industrial roles apart from being usedas biosurfactants and antimicrobials. In plant protection, lipopeptides have wide prospects owing totheirpore-forming ability in pathogens, siderophore activity, biofilm inhibition, and dislodging activity, preventing colonization bypathogens, antiviral activity, etc. Microbes with lipopeptides that haveall these actions are good biocontrol agents. Exploring these antimicrobial compounds could widen the vistasof biological pest control for existing and emerging plant pathogens. The broader diversity and strong antimicrobial behavior of lipopeptides could be a boon for dealing withcomplex pathosystems and controlling diseases of greater economic importance. Understanding which and how these compounds modulate the synthesis and production of defense-related biomolecules in the plants is a key question—the answer of whichneeds in-depth investigation. The present reviewprovides a comprehensive picture of important lipopeptides produced by plant microbiome, their isolation, characterization, mechanisms of disease control, behavior against phytopathogens to understand different aspects of antagonism, and potential prospects for future explorations as antimicrobial agents. Understanding and exploring the antimicrobial lipopeptides from bacteria and fungi could also open upan entire new arena of biopesticides for effective control of devastating plant diseases. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
Linking Soil Microbial Diversity to Modern Agriculture Practices: A Review
(MDPI, 2022) Amrita Gupta; Udai B. Singh; Pramod K. Sahu; Surinder Paul; Adarsh Kumar; Deepti Malviya; Shailendra Singh; Pandiyan Kuppusamy; Prakash Singh; Diby Paul; Jai P. Rai; Harsh V. Singh; Madhab C. Manna; Theodore C. Crusberg; Arun Kumar; Anil K. Saxena
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. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
Lipoprotein (a) and diabetic retinopathy
(2009) S.K. Singh; M.K. Singh; Shailendra Singh; T.B. Singh
Introduction: Lipoprotein little 'a' [Lp (a)] has been implicated in atherosclerotic vascular disease. Its association with diabetic retinopathy has been investigated in the present study. Methods: In this cross-sectional study, 51 male patients with diabetes mellitus were selected. Detailed clinical evaluation and examination of eye including fundus was done. Laboratory investigations included fasting and post-prandial blood glucose, lipid profile, blood urea, 24 h urinary protein excretion and Lp (a) levels in serum. Results: Out of the 51 patients selected in this study, 25 patients had non-proliferative diabetic retinopathy (NPDR), 14 had proliferative diabetic retinopathy (PDR) and 12 patients had no diabetic retinopathy (DR). Serum triglyceride, cholesterol/HDL ratio and lipid index had no relationship with severity of DR. It was interesting observation that HDL was higher and serum Lp (a) level was lower in patients with PDR than with NPDR. Conclusion: Lp (a) level is elevated in patients with DR. A causal relationship between Lp (a) and DR is presumptive. Interestingly patients with PDR had lower Lp (a) and higher HDL than with NPDR. This could suggest that atherogenic phenotype of dyslipidemia in patients with diabetes retards development of severe diabetic retinopathy. © 2009.
Load Shedding in Deregulation Environment and Impact of Photovoltaic System with SMES
(Elsevier Ltd, 2016) Shailendra Singh; Deepak Tyagi; Ashwani Kumar; Saurabh Chanana
With the continuous increase in the load, the frequency of the system goes on decreasing and it reaches to its minimum allowable value after the further increase in load will result in more frequent drop resulting in the need of load shedding. To avoid load shedding and control of the frequency of the systems some approach have discussed here. The paper includes modeling of SMES with solar PV array for frequency control of three areas interconnected thermal system in deregulated environment. A comparative analysis of different load frequency control scheme such as:Using conventional integral controllerUsing PID controller,Using additional sources of energy (PV with SMES) on the basis of load to be shed have been discussed. The effects of bilateral contracts on the dynamics of a system including three areas, each of which consisting of two GENCOS and two Discos has been discussed. A case study of contract violation of DISCO's also being incorporated. For all the three strategies the critical load at which frequency of the areas tries to go below minimum allowable range also has been calculated. With the help of MATLAB software using Simulink, results have been obtained. From the comparison results indicates that on using the third strategy (with additional sources) we are increasing the efficiency of the system. When using system with PID controller and additional sources, frequency of the system doesn't go below minimum allowable range and there is requirement of load shedding has been eliminated. © 2016 The Authors.
Microalgal based biostimulants as alleviator of biotic and abiotic stresses in crop plants
(Elsevier, 2022) Sumit Kumar; Tulasi Korra; U.B. Singh; Shailendra Singh; Kartikay Bisen
Microalgae or microphytes are microscopic, unicellular organisms present in maritime and freshwater, capable for photosynthesis and produce approximately half of the atmospheric oxygen. Microalgae are gaining the attention of plant growers, agrochemicals businesses and scientists, because they have multifaceted biostimulants properties. Microalgal biostimulants (MBS) have been used in crop plants to enhance crop performance and improved agricultural sustainability. MBS are currently being used in various economically important crop plants by different applications methods like seed priming, foliar application and soil amendment. Application of MBS leads to multiple benefits including improve soil water use efficiency, reinforced rooting system, boost crop quality and mitigation of biotic and abiotic stresses like drought and salt. Microalgal biostimulants are environment friendly, beneficial for ecosystem and reduce the hazardous impact of synthetic chemicals on human, animal and plants health. MBS have multiple strategies to suppression of stresses by the production of phytohormone like compounds. In this chapter, role of microalgal biostimulants emphasizing on stress alleviation activities in plants will be discussed. It would surely helpful to understand plant- microalgal interaction. MBS are unexploited for wide adaptable used in agriculture globally, such study provides deep perception and highlights of the current researches and next generation development priorities. © 2022 Elsevier Inc. All rights reserved.
Microbial consortium mediated acceleration of the defense response in potato against Alternaria solani through prodigious inflation in phenylpropanoid derivatives and redox homeostasis
(Elsevier Ltd, 2023) Sumit Kumar; Ram Chandra; Lopamudra Behera; Ichini Sudhir; Mukesh Meena; Shailendra Singh; Chetan Keswani
The present study was carried out in a pot experiment to examine the bioefficacy of three biocontrol agents, viz., Trichoderma viride, Bacillus subtilis, and Pseudomonas fluorescens, either alone or in consortium, on plant growth promotion and activation of defense responses in potato against the early blight pathogen Alternaria solani. The results demonstrate significant enhancement in growth parameters in plants bioprimed with the triple-microbe consortium compared to other treatments. In potato, the disease incidence percentage was significantly reduced in plants treated with the triple-microbe consortium compared to untreated control plants challenged with A. solani. Potato tubers treated with the consortium and challenged with pathogen showed significant activation of defense-related enzymes such as peroxidase (PO) at 96 h after pathogen inoculation (hapi) while, both polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) at 72 hapi, compared to the individual and dual microbial consortia-treated plants. The expression of antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT) and the accumulation of pathogenesis-related proteins such as chitinase and β-1,3-glucanase were observed to be highest at 72 hapi in the triple microbe consortium as compared to other treatments. HPLC analysis revealed significant induction in polyphenolic compounds in triple-consortium bioprimed plants compared to the control at 72 hapi. Histochemical analysis of hydrogen peroxide (H2O2) clearly showed maximum accumulation of H2O2 in pathogen-inoculated control plants, while the lowest was observed in triple-microbe consortium at 72 hapi. The findings of this study suggest that biopriming with a microbial consortium improved plant growth and triggered defense responses against A. solani through the induction of systemic resistance via modulation of the phenylpropanoid pathway and antioxidative network. © 2023 The Authors
Microbial Interactions in the Rhizosphere Contributing Crop Resilience to Biotic and Abiotic Stresses
(Springer, 2020) Deepti Malviya; Udai B. Singh; Shailendra Singh; Pramod K. Sahu; K. Pandiyan; Abhijeet S. Kashyap; Nazia Manzar; Pawan K. Sharma; H.V. Singh; Jai P. Rai; Sushil K. Sharma
Rhizosphere is a hot spot where specific kinds of diverse microbial communities develop under the influence of exudates from plant roots and in turn modulate growth and development of the plant. Such communities with or without interactions perform an array of functions, including nitrogen fixation, P, Zn, Si and K-solubilization, siderophore production, ammonification, hormones production, ACC deaminase production, ethylene production, anammox, comammox, nitrification, denitrification, antagonisms, induce resistance to plant, C-sequestration, volatile production, secondary metabolites production and many others that are known to modulate soil and plant health contributing to the corresponding responses to various stresses of biotic and abiotic nature. The magnitude of resilience of plant to biotic and abiotic stresses is completely dependent on types of communities and their interactions. With enhanced knowledge and understanding about rhizosphere, researchers are evaluating various approaches to engineer rhizosphere in such way that it enables plant to enhance the productivity and sustain it while maintaining soil health. This chapter highlights detailed account of microbial interactions in the rhizosphere with associated mechanisms that contribute to resilience of plants to stress for better growth and development. © Springer Nature Singapore Pte Ltd. 2020.
Novel Insights into Understanding the Molecular Dialogues between Bipolaroxin and the Gα and Gβ Subunits of the Wheat Heterotrimeric G-Protein during Host–Pathogen Interaction
(MDPI, 2022) Deepti Malviya; Udai B. Singh; Budheswar Dehury; Prakash Singh; Manoj Kumar; Shailendra Singh; Anurag Chaurasia; Manoj Kumar Yadav; Raja Shankar; Manish Roy; Jai P. Rai; Arup K. Mukherjee; Ishwar Singh Solanki; Arun Kumar; Sunil Kumar; Harsh V. Singh
Spot blotch disease of wheat, caused by the fungus Bipolaris sorokiniana (Sacc.) Shoem., produces several toxins which interact with the plants and thereby increase the blightening of the wheat leaves, and Bipolaroxin is one of them. There is an urgent need to decipher the molecular interaction between wheat and the toxin Bipolaroxin for in-depth understanding of host–pathogen interactions. In the present study, we have developed the three-dimensional structure of G-protein alpha subunit from Triticum aestivum. Molecular docking studies were performed using the active site of the modeled G-protein alpha and cryo-EM structure of beta subunit from T. aestivum and ‘Bipolaroxin’. The study of protein–ligand interactions revealed that six H-bonds are mainly formed by Glu29, Ser30, Lys32, and Ala177 of G-alpha with Bipolaroxin. In the beta subunit, the residues of the core beta strand domain participate in the ligand interaction where Lys256, Phe306, and Leu352 formed seven H-bonds with the ligand Bipolaroxin. All-atoms molecular dynamics (MD) simulation studies were conducted for G-alpha and -beta subunit and Bipolaroxin complexes to explore the stability, conformational flexibility, and dynamic behavior of the complex system. In planta studies clearly indicated that application of Bipolaroxin significantly impacted the physio-biochemical pathways in wheat and led to the blightening of leaves in susceptible cultivars as compared to resistant ones. Further, it interacted with the Gα and Gβ subunits of G-protein, phenylpropanoid, and MAPK pathways, which is clearly supported by the qPCR results. This study gives deeper insights into understanding the molecular dialogues between Bipolaroxin and the Gα and Gβ subunits of the wheat heterotrimeric G-protein during host–pathogen interaction. © 2022 by the authors.
Optimal Location and Size of Multi-distributed Generation with Minimization of Network Losses
(Springer Science and Business Media Deutschland GmbH, 2022) Akhilesh Kumar Barnwal; Shailendra Singh; M.K. Verma
Distribution system is one of integral part of complex power system. Power losses in distribution system branches are very high rather than power losses in transmission system branches. These higher losses lead to higher operational cost in distribution system. The advancement of technology using distributed generations has been proved to be very important in optimizing network losses, environment pollution, and reliability of power systems. The DG allocation is a mixed-integer optimization problem with nonlinearity associated. In this paper, the work optimal size location and power factor of single and multiple placements of different distributed generators have been presented. Distribution network loss has been minimized for optimal power factor, size, and location of distributed generator to be optimized. Optimum size and minimum loss have been determined. Results thus obtained have been compared with the results in the literature. The proposed method has been validated on the IEEE33-bus test system. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Rudists (Bivalvia: Hippuritida) from the Lower Cretaceous Khalsi Formation, Ladakh, India, and their palaeogeographic implications
(Academic Press, 2023) Prasenjit Barman; Narendra K. Swami; Xin Rao; S.R. Mishra; Mohd Ibrahim; Shailendra Singh
Rudist fauna composed of the Radiolitidae and the Polyconitidae is reported from the Aptian–Albian Khalsi Formation, southern Ladakh, India. The rudists are identified as Auroradiolites gilgitensis, A. biconvexus, Magallanesia rutogensis, and Shajia tibetica. Among them, A. biconvexus and M. rutogensis are described first time in Ladakh. Additionally, two radiolitid specimens reported from the Saltoro Formation of the SSZ in northern Ladakh by Upadhyay (2014), are assigned to A. biconvexus, and one single specimen from Saltoro Formation which was assigned to Horiopleura sp. by Upadhyay (2014), is questionably transferred to S. tibetica in this study. The occurrence of A. gilgitensis in the early Aptian of Ladakh provides evidence for the eastern dispersal pattern of A. gilgitensis during early Aptian. The finding of M. rutogensis in Ladakh fills the geographical gap between the first plagioptychid, early Turonian Plagioptychus haueri in the Mediterranean and the previous westernmost record of M. rutogensis in Lhasa Block, and further strengthens the hypothesis that Plagioptychidae was evolved from Magallanesia or related form. The association of A. biconvexus, A. gilgitensis, and M. canaliculata support the hypothesis of southwest Asian- Pacific province for the palaeobiogeographic linkage of Auroradiolites and Horiopleura haydeni–Praecaprotina–Magallanesia. This study provides additional evidence in favour of the relatively close geographical connection and tectonic equivalence between the Ladakh and Lhasa blocks during the mid-Cretaceous. Meanwhile, it highlights the need for detailed biostratigraphic studies in other microcontinents along the northern margin of the East Tethys, which may provide critical information for their tectonic and palaeogeographic evolution. © 2022 Elsevier Ltd