Browsing by Author "Harikesh Bahadur Singh"

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A deeper insight into the symbiotic mechanism of Rhizobium spp. from the perspective of secondary metabolism
(Springer Singapore, 2019) Prachi Singh; Rahul Singh Rajput; Ratul Moni Ram; Harikesh Bahadur Singh
Rhizobia are group of organism, known globally for their nitrogen-fixing ability. In addition to nitrogen fixation, they significantly contribute to plant growth promotion and disease control. Rhizobial aptness for plant growth promotion and antagonism against a wide range of pathogens is due to its ability to produce a wide range of secondary metabolites such as HCN, siderophore, antibiotics, rhizobitoxin, lytic enzymes, IAA, phosphate solubilization and induced systemic resistance. Rhizobial inoculants, ascribed with multiple roles of nitrogen fixation, growth promotion and disease suppression, have strengthened crop productivity. This compilation urges the need to recognize and exploit the potential multifaceted secondary metabolites of rhizobia for biological control and growth promotion. © Springer Nature Singapore Pte Ltd. 2019.
A novel function of N-signaling in plants with special reference to Trichoderma interaction influencing plant growth, nitrogen use efficiency, and cross talk with plant hormones
(Springer Verlag, 2019) Bansh Narayan Singh; Padmanabh Dwivedi; Birinchi Kumar Sarma; Gopal Shankar Singh; Harikesh Bahadur Singh
Trichoderma spp. is considered as a plant growth promoter and biocontrol fungal agents. They colonize on the surface of root in most of the agriculture crops. They secrete different secondary metabolites and enzymes which promote different physiological processes as well as protect plants from various environmental stresses. This is part of their vital functions. They are widely exploited as a biocontrol agent and plant growth promoter in agricultural fields. Colonization of Trichoderma with roots can enhance nutrient acquisition from surrounding soil to root and can substantially increase nitrogen use efficiency (NUE) in crops and linked with activation of plant signaling cascade. Among Trichoderma species, only some Trichoderma species were well characterized which help in the uptake of nitrogen-containing compound (especially nitrate form) and induced nitric oxide (NO) in plants. Both nitrate and NO are known as a signaling agent, involved in plant growth and development and disease resistance. Activation of these signaling molecules may crosstalk with other signaling molecule (Ca 2+ ) and phytohormone (auxin, gibberellins, cytokinin and ethylene). This ability of Trichoderma is important to agriculture not only for increased plant growth but also to control plant diseases. Recently, Trichoderma strains have been shown to encompass the ability to regulate transcripts level of high-affinity nitrate transporters and probably it was positively regulated by NO. This review aims to focus the usage of Trichoderma strains on crops by their abilities to regulate transcript levels, probably through activation of plant N signaling transduction that improve plant health. © 2019, King Abdulaziz City for Science and Technology.
A Thorough Comprehension of Host Endophytic Interaction Entailing the Biospherical Benefits: A Metabolomic Perspective
(Springer Science and Business Media B.V., 2019) Shatrupa Ray; Jyoti Singh; Rahul Singh Rajput; Smriti Yadav; Surendra Singh; Harikesh Bahadur Singh
Endophytism is the phenomenon of in planta residency and mutualistic association of microbes with hosts without causing any disease symptoms. The multifaceted attributes of endophytes include plant growth promotion as well as resistance of the host to several forms of abiotic or biotic stresses. Moreover, endophytes are reported to manipulate the rhizospheric microbiota as well as the microbiota present within plants so as to amplify the host beneficial mechanisms. Endophyte mediated host beneficial traits become far more significant owing to the differential recruitment of endophytes by host under varying root exudate profile, host’s age, as well as host-endophyte compatibility. However, in spite of such beneficial attributes, our understanding of endophytes is still quite limited and inadequate. Thus, the true potential of endophytes can be particularly harnessed when we gain a thorough insight on the molecular mechanisms responsible for mutualistic host-endophyte interaction. In this chapter, we present an exhaustive investigation of endophyte-plant interaction, beginning from chemotactic attraction of the supposed endophytic microflora from soil to establishment of endophytism. We will also focus on the endophyte-directed metabolite biosynthesis aiding in effective host functioning. © 2019, Springer Nature Switzerland AG.
Adaptive soil management: From theory to practices
(Springer Singapore, 2017) Amitava Rakshit; Purushothaman Chirakuzhyil Abhilash; Harikesh Bahadur Singh; Subhadip Ghosh
The book focuses in detail on learning and adapting through partnerships between managers, scientists, and other stake-holders who learn together how to create and maintain sustainable resource systems. As natural areas shrink and fragment, our ability to sustain economic growth and safeguard biological diversity and ecological integrity is increasingly being put to the test. In attempting to meet this unprecedented challenge, adaptive management is becoming a viable alternative for broader application. Adaptive management is an iterative decision-making process which is both operationally and conceptually simple and which incorporates users to acknowledge and account for uncertainty, and sustain an operating environment that promotes its reduction through careful planning, evaluation, and learning until the desired results are achieved. This multifaceted approach requires clearly defined management objectives to guide decisions about what actions to take, and explicit assumptions about expected outcomes to compare against actual outcomes. In this edited book, we address the issue by pursuing a holistic and systematic approach that utilizes natural resources to reap sustainable environmental, economic and social benefits for adaptive management, helping to ensure that relationships between land, water and plants are managed in ways that mimic nature. © Springer Nature Singapore Pte Ltd. 2017. All rights reserved.
Advances in seed priming
(Springer Singapore, 2018) Amitava Rakshit; Harikesh Bahadur Singh
Most crop plants grow in environments that are suboptimal, which prevents the plants from attaining their full genetic potential for growth and reproduction. Stress due to abiotic and biotic agents has a significant effect on world food production. Annually, an estimated 15% of global yields are lost, but this figure belies far greater losses for specific food systems and the people whose existence is dependent upon them, particularly in developing countries. Current efforts to mitigate these losses are worryingly over-reliant on the use of sophisticated and costly chemicals /measures with substantial economic and environmental costs, or on the development of efficient and smart crop varieties, which can take decades. What we need is a broad range of safe, robust and equitable solutions for food producers. One under-investigated approach is that of utilizing the crop plant's innate immune system to resist stress. More specifically, the innate immune system can be sensitized or 'primed' to respond more quickly and strongly to protect the plant against stresses. However, a strategy of employing priming in combination with reduced pesticide use can enhance protection, and help to meet commitments to reducing chemical inputs in agriculture. This book discusses in detail different segments of priming in addressing stress factors and traits to increase competitiveness against all odds. Adopting a holistic and systematic approach, it addresses priming to counter climate-change related adverse effects coupled with pest and pathogen related stress on the productivity of crops utilizing natural resources to reap sustainable environmental, economic and social benefits for potential productivity of crops, maintaining synergy between soil, water and plants in ways that mimic nature. © Springer Nature Singapore Pte Ltd. 2018. All rights reserved.
Agriculturally important microorganisms: Commercialization and regulatory requirements in Asia
(Springer Singapore, 2016) Chetan Keswani; Birinchi Kumar Sarma; Harikesh Bahadur Singh
The main focus of this book is to survey the current status of research, development and use of agriculturally important microorganisms in Asian countries and develop a strategy for addressing critical issues various policy constraints due to which bio-pesticides have found limited applications. In this book the editors have tried to develop a consensus on issues of such as quality requirements, quality control, regulatory management, commercialization and marketing of agriculturally important microorganisms in Asian countries. All these issues are discussed at national level by competent authorities of Asian countries including India, China, Malaysia, Iran, Taiwan, Israel, Sri Lanka, Vietnam and Philippines. © Springer Science+Business Media Singapore 2016.
An insight into the biodiversity and biotechnology of Fusarium species
(Elsevier, 2025) Jeetu Narware; Prachi Singh; Pitambara; Shraddha Bhaskar Sawant; Devanshu Dev; Harikesh Bahadur Singh
Fusarium species is one of the major fungi that poses challenges for food and nutritional security, as this fungus can able to cause up to 100% crop loss in many crop plants. Fusarium spp. have a wide host range and can produce a variety of symptoms in their hosts, including rot, canker, blights, and wilt. Because of the great biodiversity of the fungal species and its being soil-borne in nature, it can be linked to a variety of soil types and disseminated worldwide. Managing the fungus can be extremely challenging, leading to significant crop losses and financial losses. The fungus can survive for several years with the formation of chlamydospores or perennating structures in the soil and seeds. Therefore, it is imperative to investigate the distribution and diversity of this fungus in order to comprehend its nature and mechanism. Fusarium spp. are ubiquitous, have different ecological niches, and are soil-borne, which makes it difficult to study and manage the fungus. In light of these difficulties, Fusarium poses problems; hence, biotechnology interventions are vital for precise and timely identification and diagnosis of the fungus as well as for pathogen management. Plant pathologists have used a variety of biotechnological tools, including RNA interference (RNAi), HIGS, VIGS, genome analysis, and sequencing techniques, to better comprehend nature and biodiversity. The fungus Fusarium is worth studying in detail and gathering as much information as possible for the scientific community to better manage the diseases produced by these species due to their expanding host range and geographical presence. © 2025 Elsevier Inc. All rights reserved.
Arbuscular mycorrhizal colonization and activation of plant defense responses against phytopathogens
(Springer Singapore, 2019) Anupam Maharshi; Gagan Kumar; Arpan Mukherjee; Richa Raghuwanshi; Harikesh Bahadur Singh; Birinchi Kumar Sarma
Arbuscular mycorrhizal fungi (AMF) are potentially mutualistic biotrophs of plants and improve water supply and nutrient uptake in host plants. In exchange of this, it takes a part of photosynthate from the host plant to fulfill its metabolic requirements. Despite having its own immune system, plant gets attacked by various pathogens and therefore needs support to overcome such challenges and to become stabilized in such hostile environment. AMF colonization helps the plants either directly or indirectly to face the challenges of biotic and abiotic stresses. Several physiological and biochemical changes occur in the host plant and mycorrhizosphere following colonization of roots by AMF, and AMF colonization also affects interactions of the host plants with a diverse range of both above- and belowground organisms. Protective effects of AMF colonization against pests, pathogens, and stem or root parasitic plants were described in many agriculturally important crop species. These mechanisms not only improve plant nutrition consumption and competition but also play a significant role in plant defense activation. Successful establishment of mycorrhizal species on host leads to regulation of the JA and SA signaling pathways, and it itself explains the range of protection conferred by this symbiosis. Defense activation following colonization by mycorrhizal species is associated with moderate activation of host transcription factors such as MAP kinases. Further, several other defense-related compounds are also accumulated such as PR proteins, Β-1,3-glucanases, phytoalexins, and phenolics, and deposition of callose also occurs leading to protection against various pathogens. In the present chapter, we discussed the major defense signaling aspects during plant-pathogen interactions mediated through mycorrhizal colonization in the host plant roots. © Springer Nature Singapore Pte Ltd. 2019.
Bactericidal, quorum quenching and anti-biofilm nanofactories: a new niche for nanotechnologists
(Taylor and Francis Ltd, 2017) Brahma N. Singh; Prateeksha; Dalip K. Upreti; Braj Raj Singh; Tom Defoirdt; Vijai K. Gupta; Ana Olivia De Souza; Harikesh Bahadur Singh; João C. M. Barreira; Isabel C. F. R. Ferreira; Khabat Vahabi
Despite several conventional potent antibacterial therapies, bacterial infections pose a significant threat to human health because they are emerging as the leading cause of death worldwide. Due to the development of antibiotic resistance in bacteria, there is a pressing demand to discover novel approaches for developing more effective therapies to treat multidrug-resistant bacterial strains and biofilm-associated infections. Therefore, attention has been especially devoted to a new and emerging branch of science “nanotechnology” to design non-conventional antimicrobial chemotherapies. A range of nanomaterials and nano-sized carriers for conventional antimicrobial agents have fully justified their potential to combat bacterial diseases by reducing cell viability, by attenuating quorum sensing, and by inhibiting/or eradicating biofilms. This communication summarizes emerging nano-antimicrobial therapies in treating bacterial infections, particularly using antibacterial, quorum quenching, and anti-biofilm nanomaterials as new approaches to tackle the current challenges in combating infectious diseases. © 2016 Informa UK Limited, trading as Taylor & Francis Group.
Belowground fungal volatiles perception in okra (Abelmoschus esculentus) facilitates plant growth under biotic stress
(Elsevier GmbH, 2021) Jyoti Singh; Prachi Singh; Anukool Vaishnav; Shatrupa Ray; Rahul Singh Rajput; Shiv Mohan Singh; Harikesh Bahadur Singh
Microbial volatile organic compounds (mVOCs) have great potential in plant ecophysiology, yet the role of belowground VOCs in plant stress management remains largely obscure. Analysis of biocontrol producing VOCs into the soil allow detailed insight into their interaction with soil borne pathogens for plant disease management. A root interaction trial was set up to evaluate the effects of VOCs released from Trichoderma viride BHU-V2 on soil-inhabiting fungal pathogen and okra plant growth. VOCs released into soil by T. viride BHU-V2 inhibited the growth of collar rot pathogen, Sclerotium rolfsii. Okra plants responded to VOCs by increasing the root growth (lateral roots) and total biomass content. VOCs exposure increased defense mechanism in okra plants by inducing different enzyme activities i.e. chitinase (0.89 fold), β-1,3-glucanase (0.42 fold), peroxidase (0.29 fold), polyphenol oxidase (0.33 fold) and phenylalanine lyase (0.7 fold) when inoculated with S. rolfsii. In addition, T. viride BHU-V2 secreted VOCs reduced lipid peroxidation and cell death in okra plants under pathogen inoculated condition. GC/MS analysis of VOCs blend revealed that T. viride BHU-V2 produced more number of antifungal compounds in soil medium as compared to standard medium. Based on the above observations it is concluded that okra plant roots perceive VOCs secreted by T. viride BHU-V2 into soil that involved in induction of plant defense system against S. rolfsii. In an ecological context, the findings reveal that belowground microbial VOCs may play an important role in stress signaling mechanism to interact with plants. © 2021
Bio-priming Mediated Nutrient Use Efficiency of Crop Species
(Springer India, 2015) Amitava Rakshit; Kumai Sunita; Sumita Pal; Akanksha Singh; Harikesh Bahadur Singh
Soil contamination and environmental hazard from the indiscriminate and excessive application of agrochemicals on crops have been key issues for the present-day agriculture. Additionally, the risk to human health has also led to stringent regulatory framework around the use of synthetic chemicals in agriculture. Bio-inoculants have emerged as the most feasible eco-friendly solution to these issues and have been gaining considerable consumer acceptance since the time they were first introduced. Bioagents are substances containing living microorganisms which promote plant growth and maintain the soil and crop health by increasing the supply or availability of primary nutrients to the host plant. Bio-priming which involves seed priming in combination with low dosage of beneficial microorganisms is becoming a potentially prominent technique to induce profound changes in versatility of plant performance, encourage desired attributes in crop growth, and stabilize the efficacy of biological agents in the present fragile setup of agriculture by reducing dependency on chemical inputs and offers an attractive option for resource-poor farmers being an easy and cost effective method. The most prominent contributors in fungi and bacteria which are used extensively in bio-priming include Trichoderma, Pseudomonas, Glomus, Bacillus, Agrobacterium, and Gliocladium. Here in this review, we discuss the potential of bio-priming for improving crop growth and nutrient use efficiency and provide an assessment of bioagents currently used with crop species and key limitations involved. © Springer India 2015.
Biochar-Mediated Suppression of Soil-Borne Pathogens in Agronomically Important Crops: An Outlook
(Springer Nature, 2023) Talat Ilyas; Deepti Malviya; Zaryab Shafi; Mohammad Shahid; Shailesh K. Vishwakarma; Bavita Yadav; Udai B. Singh; Jai P. Rai; Harikesh Bahadur Singh; Harsh V. Singh
Biochar is solid produce acquired by the heating of biological or carbon-based material in the complete or fractional presence of oxygen and is used as a soil amendment. The numerous valuable properties of biochar on the physical, biological, and chemical properties of soil as well as on plant condition and improvement are extensively acknowledged. The amendment of biochar has also been frequently debated for its properties of suppression of diseases. Nevertheless, the principal mechanisms for these properties are extremely complex and generally unidentified. It is anticipated that the composition of plant root exudate that alters the biochemical and microbial properties in the soil and the stimulation of defense mechanisms of plants due to the amendments of biochar are some critical reasons influencing pathogenic dominance. Further comprehensive studies are required for understanding the detailed connections of plant-pathogen coordination with various types of biochar that will support accomplishing maximum aid of biochar addition for the protection of plants from numerous soil-borne pathogens. In this chapter, the perspective of biochar for the regulation of pathogenic diseases is discussed, specifically the communications with plant pathogenic fungi under contradictory environmental circumstances. It is concluded that the amendment of biochar with soil could be an encouraging approach for the combined management of pests and pathogens. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023.
Biochemical and histochemical analyses revealing endophytic Alcaligenes faecalis mediated suppression of oxidative stress in Abelmoschus esculentus challenged with Sclerotium rolfsii
(Elsevier Masson SAS, 2016) Shatrupa Ray; Vivek Singh; Surendra Singh; Birinchi Kumar Sarma; Harikesh Bahadur Singh
Sclerotium rolfsii is a highly aggressive pathogen that causes huge economic losses, especially in temperate climates. Alcaligenes faecalis, particularly in endophytic form, has rarely been used to control this fungus. In this study, endophytic Alcaligenes sp. strain BHU 12, BHU 16 (isolated from Abelmoschus esculentus leaf) and BHU M7 (isolated from Andrographis paniculata leaf) were reported to trigger a wide range of host defenses in Okra plant against the collar-rot pathogen S. rolfsii. Endophytic colonization of the strains in ten days old plants was assessed through re-isolation of the rif-tagged strains on rifampicin augmented nutrient agar media. The ability of the endophytic strains to induce systemic defense responses in above-ground organs was assessed by collecting leaf tissues of the Okra plants grown under non-gnotobiotic conditions at different time intervals post seedling bacterization with the endophytic biocontrol agents. The pathogen challenged unprimed plants exhibited flaccidity of the stem and leaves at 48 h post infection (hpi) in contrast to the bioprimed and challenged plants. Biochemical and histochemical analyses explained the above phenomenon as activation of phyto-peroxidases leading to an increased metabolism of the reactive oxygen species (ROS), accompanied by activation of the phenylpropanoid network and a subsequent enhancement in plant phenolics. Interestingly, though the maximum increase in the defense pathways was observed in treatments with native endophytes of Okra plant, yet the enhancement in antioxidant pathway due to A. paniculata borne endophytes was also quite significant. Thus, this work clearly demonstrates how Okra plants respond to the “non-hostile” colonization of bacterial endophytes and how induced defense response can contribute to the biocontrol activity of the endophytic strains. © 2016 Elsevier Masson SAS
Biocontrol agents-mediated suppression of oxalic acid induced cell death during Sclerotinia sclerotiorum-pea interaction
(Wiley-VCH Verlag, 2015) Akansha Jain; Akanksha Singh; Surendra Singh; Birinchi Kumar Sarma; Harikesh Bahadur Singh
Oxalic acid (OA) is an important pathogenic factor during early Sclerotinia sclerotiorum-host interaction and might work by reducing hydrogen peroxide production (H2O2). In the present investigation, oxalic acid-induced cell death in pea was studied. Pea plants treated with biocontrol agents (BCAs) viz., Pseudomonas aeruginosa PJHU15, Bacillus subtilis BHHU100, and Trichoderma harzianum TNHU27 either singly and/or in consortium acted on S. sclerotiorum indirectly by enabling plants to inhibit the OA-mediated suppression of oxidative burst via induction of H2O2. Our results showed that BCA treated plants upon treatment with culture filtrate of the pathogen, conferred the resistance via. significantly decreasing relative cell death of pea against S. sclerotiorum compared to control plants without BCA treatment but treated with the culture filtrate of the pathogen. The results obtained from the present study indicate that the microbes especially in consortia play significant role in protection against S. sclerotiorum by modulating oxidative burst and partially enhancing tolerance by increasing the H2O2 generation, which is otherwise suppressed by OA produced by the pathogen. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Biological management of Sclerotinia rot of bean through enhanced host defense responses triggered by Pseudomonas and Trichoderma species
(Journal of Pure and Applied Microbiology, 2015) Ratul Moni Ram; Akansha Jain; Akanksha Singh; Harikesh Bahadur Singh
Plant growth promoting microorganisms have been reported to induce systemic resistance in plants. In the present study, a consortium comprising of Trichoderma harzianum and Pseudomonas aeruginosa were evaluated for their efficacy to control Sclerotinia rot of bean. Upon infection of bean plants with the S. scIerotiorum resulted in substantial changes in enzymatic and non-enzymatic defense related compounds. The induction of phenylalanine ammonia-lyase (PAL), peroxidase (POx), polyphenoloxidase (PPO), superoxide dismutase (SOD), and the accumulation of proline and phenols in bean leaves were studied periodically at 2 d intervals after pathogen infection. Levels of PAL and phenols were induced most rapidly and increased significantly in all the treatments after pathogen challenge and reached maximum after 2 d and 4 d of pathogen challenge, respectively. Similarly, the activities of POx, PPO, SOD, along with proline content was also found to increase consistently and reached maximum at 6 d after pathogen challenge and their content was maximum in plants treated with microbial consortium. These results demonstrated that interaction of microorganism in rhizosphere could provide enhanced tolerance against pathogen through induction of host defenserelated compounds.
Biological management of Sclerotinia sclerotiorum in pea using plant growth promoting microbial consortium
(Wiley-VCH Verlag, 2015) Akansha Jain; Akanksha Singh; Surendra Singh; Harikesh Bahadur Singh
The beneficial plant-microbe interactions play crucial roles in protection against large number of plant pathogens causing disease. The present study aims to investigate the growth promoting traits induced by beneficial microbes namely Pseudomonas aeruginosa PJHU15, Trichoderma harzianum TNHU27, and Bacillus subtilis BHHU100 treated singly and in combinations under greenhouse and field conditions to control Sclerotinia sclerotiorum. Plants treated with three microbe consortium enhanced plant growth maximally both in the presence and absence of the pathogen. Increase in plant length, total biomass, number of leaves, nodules and secondary roots, total chlorophyll and carotenoid content, and yield were recorded in plants treated with microbial consortia. Also, a decrease in plant mortality was observed in plants treated with microbial consortia in comparison to untreated control plants challenged with S. sclerotiorum. Furthermore, the decrease in disease of all the treatments can be associated with differential improvement of growth induced in pea. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Commercialization of arbuscular mycorrhizal technology in agriculture and forestry
(Springer Singapore, 2016) Sumita Pal; Harikesh Bahadur Singh; Alvina Farooqui; Amitava Rakshit
The ecto- and endomycorrhizal fungi are commonly occurring mycorrhizas and are very significant in relation to the growth of agricultural crops and forest trees. Mycorrhizal technology can advantageously be applied in agricultural and horticultural crops as well as forestry for better nutrient utilization offsetting ecological and environmental concerns by reduced chemical input use, disease management by reducing biotic stress by pathogenic fungi, and more effective land use management. However, even though the inoculation of plants with mycorrhiza is a familiar practice, the formulation of inocula with a dependable and steady effect under field situation is still a bottleneck for their wider use. The option of the technology for inocula production and of the carrier for the formulation is key to their booming application. In this review, we focus on the status of commercialization of mycorrhizal fungi as a gadget for enhancing plant growth and productivity. © Springer Science+Business Media Singapore 2016.
Comparative proteomic analysis in pea treated with microbial consortia of beneficial microbes reveals changes in the protein network to enhance resistance against Sclerotinia sclerotiorum
(Elsevier GmbH, 2015) Akansha Jain; Akanksha Singh; Surendra Singh; Vinay Singh; Harikesh Bahadur Singh
Microbial consortia may provide protection against pathogenic ingress via enhancing plant defense responses. Pseudomonas aeruginosa PJHU15, Trichoderma harzianum TNHU27 and Bacillus subtilis BHHU100 were used either singly or in consortia in the pea rhizosphere to observe proteome level changes upon Sclerotinia sclerotiorum challenge. Thirty proteins were found to increase or decrease differentially in 2-DE gels of pea leaves, out of which 25 were identified by MALDI-TOF MS or MS/MS. These proteins were classified into several functional categories including photosynthesis, respiration, phenylpropanoid metabolism, protein synthesis, stress regulation, carbohydrate and nitrogen metabolism and disease/defense-related processes. The respective homologue of each protein identified was trapped in Pisum sativum and a phylogenetic tree was constructed to check the ancestry. The proteomic view of the defense response to S. sclerotiorum in pea, in the presence of beneficial microbes, highlights the enhanced protection that can be provided by these microbes in challenged plants. © 2015 Elsevier GmbH.
Comparative Study of Trichoderma BHU-1 Mediated Drought Alleviation of Susceptible and Tolerant Rice Cultivars
(Journal of Pure and Applied Microbiology, 2025) Ram Nandan Yadav; Renu Yadav; Najam Waris Zaidi; Harikesh Bahadur Singh; Prashant Bisen; Md Mahtab Rashid; Sudheer Kumar Yadav
The study investigated Trichoderma-mediated morphological and biochemical responses in droughtsusceptible and tolerant rice cultivars, namely IR-64 and DRR-44, under drought-stressed and normal conditions. Various morphological and biochemical parameters were recorded 30, 60, and 90 days after transplanting. The shoot length was insignificant, while the root length was significant in droughtsusceptible DRR-44 compared to non-stressed plants. The number of roots was also significant in Trichoderma BHU-1 treated plants of both cultivars. Proline content was more substantial in drought susceptible cultivars than tolerant and similarly, lignin, TPC, PAL, and PO activities were higher in Trichoderma BHU-1 treated drought-stressed plants than in normal ones. The result revealed that Trichoderma BHU-1 treatment modulates an increase in root length, shoot length, and the total number of tillers and roots under drought conditions. It also maintained the level of phenolics in plants by upregulating the pathway thereby helping the plant to sustain drought. © The Author(s) 2025.
Compatible rhizosphere microbes mediated alleviation of biotic stress in chickpea through enhanced antioxidant and phenylpropanoid activities
(2013) Akanksha Singh; Birinchi Kumar Sarma; Ram Sanmukh Upadhyay; Harikesh Bahadur Singh
The study was conducted to examine efficacy of a rhizospheric microbial consortium comprising of a fluorescent Pseudomonas (PHU094), Trichoderma (THU0816) and Rhizobium (RL091) strain on activation of physiological defense responses in chickpea against biotic stress caused by the collar rot pathogen Sclerotium rolfsii. Results of individual microbes were compared with dual and triple strain mixture treatments with reduced microbial load (1/2 and 1/3rd, respectively, of individual microbial load compared to single microbe application) in the mixtures. Periodical studies revealed maximum activities of phenylalanine ammonia lyase [E.C. 4.1.3.5] and polyphenol oxidase [E.C. 1.14.18.1] and accumulation of total phenol content in chickpea in the triple microbe consortium treated plants challenged with the pathogen compared to the single microbe and dual microbial consortia. Similarly, the expression of the antioxidant enzymes superoxide dismutase [E.C.1.15.1.1] and peroxidase [E.C.1.11.1.7] was also highest in the triple microbial consortium which was correlated with lesser lipid peroxidation in chickpea under the biotic stress. Histochemical staining clearly showed maximum and uniform lignification in vascular bundles of chickpea stem sections treated with the triple microbes. The physiological responses were directly correlated with the mortality rate as least plant mortality was recorded in the triple microbe consortium treated plants. The results thus suggest an augmented elicitation of stress response in chickpea under S. rolfsii stress by the triple microbial consortium in a synergistic manner under reduced microbial load. © 2012 Elsevier GmbH.