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Abiotic stresses including heavy metal toxicity, drought, salt and temperature extremes disrupt the plant growth and development and lowers crop output. Presence of environmental pollutants further causes plants suffering and restrict their ability to thrive. Overuse of chemical fertilizers to reduce the negative impact of these stresses is deteriorating the environment and induces various secondary stresses to plants. Therefore, an environmentally friendly strategy like utilizing plant growth-promoting rhizobacteria (PGPR) is a promising way to lessen the negative effects of stressors and to boost plant growth in stressful conditions. These are naturally occurring inhabitants of various environments, an essential component of the natural ecosystem and have remarkable abilities to promote plant growth. Furthermore, multifarious role of PGPR has recently been widely exploited to restore natural soil against a range of contaminants and to mitigate abiotic stress. For instance, PGPR may mitigate metal phytotoxicity by boosting metal translocation inside the plant and changing the metal bioavailability in the soil. PGPR have been also reported to mitigate other abiotic stress and to degrade environmental contaminants remarkably. Nevertheless, despite the substantial quantity of information that has been produced in the meantime, there has not been much advancement in either the knowledge of the processes behind the alleged positive benefits or in effective yield improvements by PGPR inoculation. This review focuses on addressing the progress accomplished in understanding various mechanisms behind the protective benefits of PGPR against a variety of abiotic stressors and in environmental cleanups and identifying the cause of the restricted applicability in real-world.
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Estrés Fisiológico , Contaminantes del Suelo , Microbiología del Suelo , Biodegradación Ambiental , Metales PesadosRESUMEN
Cd is highly mobile, non-essential trace element, that has become serious environmental issue due to its elevated concentration in soil. The present study was taken up to work out salutary effect of melatonin (Mlt) and PGPR ((Pseudomonas putida (Pp), Pseudomonas fluorescens (Pf) in 10 days old Cd stressed (0.3 mM) Brassica juncea L. seedlings. The present work investigated growth characteristics, photosynthetic pigments, secondary metabolites in melatonin-PGPR inoculated B. juncea seedlings. It was backed by molecular studies entailing RT-PCR and transcriptomic analyses. Our results revealed, substantial increase in photosynthetic pigments and secondary metabolites, after treatment with melatonin, P.putida, P. fluorescens in Cd stressed B. juncea seedlings, further validated with transcriptome analysis. Comparative transcriptome analyses identified 455, 5953, 3368, 2238 upregulated and 4921, 430, 137, 27 down regulated DEGs, Cn-vs-Cd, Cd-vs-Mlt, Cd-vs-Mlt-Pp-Pf, Cd-vs-Mlt-Pp-Pf-Cd comparative groups respectively. In depth exploration of genome analyses (Gene ontology, Kyoto encyclopaedia of genes), revealed that Cd modifies the expression patterns of most DEGs mainly associated to photosystem and chlorophyll synthesis. Also, gene expression studies for key photosynthetic genes (psb A, psb B, CHS, PAL, and PSY) suggested enhanced expression in melatonin-rhizobacteria treated Cd stressed B. juncea seedlings. Overall, results provide new insights into probable mechanism of Mlt-PGPR induced protection to photosynthesis in Cd stressed B. juncea plants.
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Cadmio , Melatonina , Planta de la Mostaza , Fotosíntesis , Transcriptoma , Melatonina/farmacología , Planta de la Mostaza/efectos de los fármacos , Planta de la Mostaza/genética , Planta de la Mostaza/microbiología , Planta de la Mostaza/metabolismo , Planta de la Mostaza/crecimiento & desarrollo , Fotosíntesis/efectos de los fármacos , Cadmio/toxicidad , Transcriptoma/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Plantones/efectos de los fármacos , Pseudomonas putida/efectos de los fármacos , Pseudomonas putida/genética , Pseudomonas putida/metabolismoRESUMEN
Bacterial resistance toward available therapeutic agents has become a nightmare for the healthcare system, causing significant mortality as well as prolonged hospitalization, thereby needing the urgent attention of research groups working on antimicrobial drug development worldwide. Molecular hybridization is a well-established tool for developing multifunctional compounds to tackle drug resistance. Inspired by the antibacterial profiles of isatin and thymol, along with the efficiency of a triazole linker in molecular hybridization, herein, we report the design, synthesis and antibacterial activity of a novel series of triazole tethered thymol-isatin hybrids. Most of the hybrids exhibited a broad-spectrum antibacterial efficacy against standard human pathogenic as well as clinically isolated multidrug-resistant bacterial strains listed in the WHO's 'priority pathogen' list and also in the ESKAPE group. Among them, hybrid compound AS8 was the most effective against methicillin-resistant Staphylococcus aureus (MIC = 1.9 µM and MBC = 3.9 µM), exhibiting biofilm inhibitory potential. AS8 exhibited dehydrosqualene synthase (CrtM) inhibitory potential in MRSA and decreased the production of virulence factor staphyloxanthin, which is one of the key mechanisms of its anti-MRSA efficacy, which was further supported by molecular docking and simulation studies. Moreover, AS8 was found to be non-toxic and showed a potent in vivo antibacterial efficacy (90% survival at 10 mg kg-1) as well as a modulated immune response in the larva-based (Galleria mellonella) model of systemic infections. Overall findings confirmed that AS8 can be a promising candidate or take the lead in the treatment and further drug development against drug-resistant infectious diseases, especially against MRSA infections.
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In the face of escalating salinity stress challenges in agricultural systems, this review article delves into the harmonious partnership between hydrogen sulfide (H2S) and nitric oxide (NO) as they collectively act as formidable defenders of plants. Once considered as harmful pollutants, H2S and NO have emerged as pivotal gaseous signal molecules that profoundly influence various facets of plant life. Their roles span from enhancing seed germination to promoting overall growth and development. Moreover, these molecules play a crucial role in bolstering stress tolerance mechanisms and maintaining essential plant homeostasis. This review navigates through the intricate signaling pathways associated with H2S and NO, elucidating their synergistic effects in combating salinity stress. We explore their potential to enhance crop productivity, thereby ensuring food security in saline-affected regions. In an era marked by pressing environmental challenges, the manipulation of H2S and NO presents promising avenues for sustainable agriculture, offering a beacon of hope for the future of global food production.
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Sulfuro de Hidrógeno , Óxido Nítrico , Óxido Nítrico/metabolismo , Sulfuro de Hidrógeno/metabolismo , Estrés Salino , Plantas/metabolismo , Estrés Fisiológico , SalinidadRESUMEN
A survey was undertaken to isolate entomopathogenic nematodes from Amritsar district of Punjab, India. Out of 20 soil samples collected, two were found positive for the presence of nematodes. 18S and ITS rDNA gene sequencing revealed their identity as Metarhabditis amsactae. To assess its biocontrol potential, Galleria mellonella larvae were treated with concentrations of 20, 40, 80 and 160 IJs/L (infective juveniles/larva) and mortality was recorded from 24 h up to 96 h of nematode exposure. Distilled water without nematodes was used as an untreated control. M. amsactae showed potent larvicidal activity against G. mellonella that was found to be concentration and time dependent. Nematode infection caused 93.33 % larval mortality at 80 IJs/L after 72 h of treatment. 100 % mortality was observed after 96 h. No mortality was observed in control. To evaluate the immunomodulatory effects of M. amsactae, G. mellonella larvae were infected with 100 IJs/L and activities of antioxidant and detoxifying enzymes viz., superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APOX), phenol oxidase (PO), glutathione-S-transferase (GST) and acetylcholine esterase (AChE) were appraised after 12, 24, 36 and 48 h of nematode exposure. Malondialdehyde content was also determined. The results obtained demonstrated a significant elevation in all the enzyme activities at all time intervals in treated larvae when compared with untreated control. MDA levels were also enhanced in response to nematode infection. Thus, the present study revealed high insecticidal potential and immunomodulatory effects of M. amsactae on G. mellonella that should be further explored on other insect pests as well.
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Insecticidas , Mariposas Nocturnas , Nematodos , Infecciones por Nematodos , Rhabditoidea , Animales , Agentes de Control Biológico/farmacología , Insecticidas/farmacología , LarvaRESUMEN
Farming, food processing, animal husbandry and other agro-based activities contribute to global environmental degradation by producing millions of tons of organic and inorganic solid waste. In terms of sustainable agriculture, agricultural waste management and conversion into useful products are essential. In addition, plants are facing various kinds of biotic stress, which ultimately affects their defense system. Altered defense systems in plants ultimately lead to the death of plants and a reduction in crop production. The present study is designed to keep the abovementioned fact in mind, which mainly focuses on the reuse of agricultural waste and its application to the antioxidant potential and structural components of tomato plants during nematode stress. In the present study, neem leaves were collected and mixed with cattle dung for the preparation of vermicompost. Then, tomato seeds were pre-treated with vermicompost extract before being germinated in earthen pots. After germination, they were transplanted to separate pots and inoculated with freshly hatched juveniles of Meloidogyne incognita. The experiments were conducted for 10 days under glass house conditions, and after that, plants were harvested and various physiological (antioxidant capacity, percent electrolyte leakage) and structural markers (carbohydrate content, Fourier transform infrared spectroscopy) were analyzed. Results revealed that all physico-chemical properties make vermicompost superior as compared to soil and pre-compost material. Further, nematode stress leads to altered physiological and structural markers as compared to uninfected seedlings. However, treatment with vermicompost significantly increases carbohydrate content and antioxidative capacity in a concentration dependent manner. In addition, electrolyte leakage was found to be decrease with an increase in the concentration of vermicompost. All these findings conclude that vermicompost has strong potential to limit the damage caused by nematodes and boost the antioxidant potential of the host plants. Further, this study provides strong evidence for using vermicompost as an eco-friendly alternative to chemical nematicides and a potential strategy for agricultural waste management. This is the first study in which the tomato plant's structural and physiological markers were assessed during nematode stress after being supplemented with vermicompost under glass house conditions for an initial 10 days of nematode exposure.
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Soil and water are two important basic ecosystems for the survival of different organisms. The excessive microplastic pollutants in soil have been directly discharged into the terrestrial ecosystems. Microplastic pollutants (MPs) constitute a ubiquitous global menace due to their durability, flexibility, and tough nature. MPs posed threat to the sustainability of the ecosystem due to their small size and easy transportation via ecological series resulting in the accumulation of MPs in aquatic and terrestrial ecosystems. After being emitted into the terrestrial ecosystem, the MPs might be aged by oxidative degeneration (photo/thermal), reprecipitation (bioturbation), and hetero-accumulation. The mechanism of adsorption, degradation, and breakdown of MPs into unaffected plastic debris is accomplished by using several biological, physical, and chemical strategies. This review presents the importance of ecosystems, occurrence and sources of MPs, its toxicity, and the alteration in the ecology of the ecosystems. The inhibitory impact of MPs on the ecosystems also documents to unveil the ecological hazards of MPs. Further research is required to study the immobilization and recovery efficiency of MPs on a larger scale.
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Worldwide, biotic stress severely degrades agricultural output and increases the risk of starvation. Root-knot nematodes (Meloidogyne incognita) are one of the important endoparasites that adversely affect the growth and development in plants, thus affecting their productivity. Contrarily, humans employ a number of unfriendly techniques, such as chemical applications, to manage biotic stressors. Use of Plant Growth Regulators is an environmentally safe alternative method against chemical pesticides that can be used to defend plants from biotic stressors. Melatonin and polyamines have been broadly found in multiple physiological processes and in diverse biotic and abiotic stresses faced by plants. In the contemporaneous study, we conducted an in vitro experiment which disclosed that pretreated seeds with melatonin and spermidine (a polyamine), decreased root galls in afflicted plants and uplifted the growth of Solanum lycopersicum seedlings. According to our findings, tomato plants' photosynthetic efficiency dropped and reactive oxygen species levels dramatically rose after nematode inoculation. On the other hand, melatonin and spermidine decreased oxidative stress by scavenging hydrogen peroxide and decreased malonaldehyde. The present work investigated improvement in growth characteristics, photosynthetic pigments, antioxidative enzymes and non-antioxidative enzymes in PGR treated tomato seedlings even during the nematode stress. Confocal studies evaluated nuclear damage within root apices and intensity of blue colour was directly proportional to nuclear damage. The findings of the present investigation support the use of plant growth regulators, melatonin and spermidine as seed priming agent to manage nematode stress in plants.
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Melatonina , Nematodos , Solanum lycopersicum , Humanos , Animales , Espermidina/farmacología , Melatonina/farmacología , Reguladores del Crecimiento de las Plantas , PoliaminasRESUMEN
In plants, hydrogen sulfide (H2S) is mainly considered as a gaseous transmitter or signaling molecule that has long been recognized as an essential component of numerous plant cellular and physiological processes. Several subcellular compartments in plants use both enzymatic and non-enzymatic mechanisms to generate H2S. Under normal and stress full conditions exogenous administration of H2S supports a variety of plant developmental processes, including growth and germination, senescence, defense, maturation and antioxidant machinery in plants. Due to their gaseous nature, they are efficiently disseminated to various areas of the cell to balance antioxidant pools and supply sulphur to the cells. Numerous studies have also been reported regarding H2S ability to reduce heavy metal toxicity when combined with other signaling molecules like nitric oxide (NO), abscisic acid (ABA), calcium ion (Ca2+), hydrogen peroxide (H2O2), salicylic acid (SA), ethylene (ETH), jasmonic acid (JA), proline (Pro), and melatonin. The current study focuses on multiple pathways for JA and H2S production as well as their signaling functions in plant cells under varied circumstances, more specifically under heavy metal, which also covers role of H2S and Jasmonic acid during heavy metal stress and interaction of hydrogen sulfide with Jasmonic acid.
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Sulfuro de Hidrógeno , Metales Pesados , Sulfuro de Hidrógeno/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrógeno/metabolismo , Metales Pesados/toxicidad , Plantas/metabolismo , Estrés FisiológicoRESUMEN
The clustered regularly interspaced short palindromic repeats (CRISPR-Cas9), a genome editing tool, has gained a tremendous position due to its therapeutic efficacy, ability to counteract abiotic/biotic stresses in plants, environmental remediation and sustainable agriculture with the aim of food security. This is mainly due to their potential of precised genome modification and numerous genetic engineering protocols with versatility as well as simplicity. This technique is quite useful for crop refinement and overcoming the agricultural losses and regaining the soil fertility hampered by hazardous chemicals. Since CRISPR/Cas9 has been widely accepted in genome editing in plants, however, their revolutionised nature and progress enable genetic engineers to face numerous challenges in plant biotechnology. Therefore, nanoparticles have addressed these challenges and improved cargo delivery and genomic editing processes. Henceforth, this barrier prevents CRISPR-based genetic engineering in plants in order to show efficacy in full potential and eliminate all the barriers. This advancement accelerates the genome editing process and its applications in plant biotechnology enable us to sustain and feed the massive population under varying environments. Genome editing tools using CRISPR/Cas9 and nanotechnology are advantageous that produce transgenic-free plants that overcome global food demands. Here, in this review, we have aimed towards the mechanisms/delivery systems linked with CRISPR/Cas9 system. We have elaborated on the applications of CRISPR/Cas9 and nanotechnology-based systems for sustainable agriculture. Moreover, the challenges and limitations associated with genome editing and delivery systems have also been discussed with a special emphasis on crop improvement.
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Sistemas CRISPR-Cas , Productos Agrícolas , Productos Agrícolas/genética , Edición Génica/métodos , Plantas Modificadas Genéticamente/genética , AgriculturaRESUMEN
In modern era, various inorganic fertilizers and pesticides are used as plant growth supplements in a variety of crop in order to gain maximum output and also reported as hazardous to mankind as well as environment. In addition, some of the plants died in initial phase of the growth after germination due to poor nutrient content of the soil or exposure to biotic stresses. In the beginning of sustainable agriculture, these chemical fertilizers were replaced with some alternative growth boosters such as organic fertilizers. In the present study, vermicompost was prepared using garden waste and cattle dung followed by analysis of various physico-chemical properties. Then tomato seeds were allowed to germinate in soil and supplemented with different doses of vermicompost (0-100%). The plants were harvested after 10 and 45 days of their germination and tissues were subjected to analysis of various morphological and biochemical parameters. Morphological parameters included root length, shoot length, root fresh weight, shoot fresh weight and number of leaves. Whereas biochemical parameters such as protein content, antioxidative enzymes (catalase, superoxide dismutase, ascorbate peroxidase, polyphenol oxidase), non-enzymatic antioxidants (ascorbic acid, glutathione, tocopherol), osmolytes (proline, carbohydrate), photosynthetic pigments (chlorophyll, carotenoid) and secondary metabolites (phenol, flavonoid, anthocyanin) were estimated on UV-visible spectrophotometer using standard protocols. Further, structural analysis of plant tissue was done using fourier transform infrared spectroscopy spectra (FTIR) and carbon hydrogen nitrogen (CHN) elemental analyzer. Results obtained from the present study revealed significant difference in all morphological and biochemical markers at both 10 and 45 days intervals of time. Further, growth of all plants was found to be directly proportional to the concentration of vermicompost and exposure duration. FTIR spectra and CHN analyses reveal the breakdown of various complex compounds and their transformation from Vcom amended soil to roots of plants. This is the first study in which significant changes were observed in growth, physiology and structural composition of tomato plants at two different exposure periods (10 and 45 days) under glass house conditions which further concluded that vermicompost has a significant potential for increasing plant growth.
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Solanum lycopersicum , Animales , Bovinos , Fertilizantes , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Plantas/metabolismo , Suelo/químicaRESUMEN
Nitric oxide (NO) is a diatomic gaseous molecule, which plays different roles in different strata of organisms. Discovered as a neurotransmitter in animals, NO has now gained a significant place in plant signaling cascade. NO regulates plant growth and several developmental processes including germination, root formation, stomatal movement, maturation and defense in plants. Due to its gaseous state, it is unchallenging for NO to reach different parts of cell and counterpoise antioxidant pool. Various abiotic and biotic stresses act on plants and affect their growth and development. NO plays a pivotal role in alleviating toxic effects caused by various stressors by modulating oxidative stress, antioxidant defense mechanism, metal transport and ion homeostasis. It also modulates the activity of some transcriptional factors during stress conditions in plants. Besides its role during stress conditions, interaction of NO with other signaling molecules such as other gasotransmitters (hydrogen sulfide), phytohormones (abscisic acid, salicylic acid, jasmonic acid, gibberellin, ethylene, brassinosteroids, cytokinins and auxin), ions, polyamines, etc. has been demonstrated. These interactions play vital role in alleviating plant stress by modulating defense mechanisms in plants. Taking all these aspects into consideration, the current review focuses on the role of NO and its interaction with other signaling molecules in regulating plant growth and development, particularly under stressed conditions.
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Antioxidantes , Óxido Nítrico , Plantas , Estrés Fisiológico/fisiología , Reguladores del Crecimiento de las PlantasRESUMEN
The agricultural sector is a foremost contributing factor in supplying food at the global scale. There are plethora of biotic as well as abiotic stressors that act as major constraints for the agricultural sector in terms of global food demand, quality, and security. Stresses affect rhizosphere and their communities, root growth, plant health, and productivity. They also alter numerous plant physiological and metabolic processes. Moreover, they impact transcriptomic and metabolomic changes, causing alteration in root exudates and affecting microbial communities. Since the evolution of hazardous pesticides and fertilizers, productivity has experienced elevation but at the cost of impeding soil fertility thereby causing environmental pollution. Therefore, it is crucial to develop sustainable and safe means for crop production. The emergence of various pieces of evidence depicting the alterations and abundance of microbes under stressed conditions proved to be beneficial and outstanding for maintaining plant legacy and stimulating their survival. Beneficial microbes offer a great potential for plant growth during stresses in an economical manner. Moreover, they promote plant growth with regulating phytohormones, nutrient acquisition, siderophore synthesis, and induce antioxidant system. Besides, acquired or induced systemic resistance also counteracts biotic stresses. The phytomicrobiome exploration is crucial to determine the growth-promoting traits, colonization, and protection of plants from adversities caused by stresses. Further, the intercommunications among rhizosphere through a direct/indirect manner facilitate growth and form complex network. The phytomicrobiome communications are essential for promoting sustainable agriculture where microbes act as ecological engineers for environment. In this review, we have reviewed our building knowledge about the role of microbes in plant defense and stress-mediated alterations within the phytomicrobiomes. We have depicted the defense biome concept that infers the design of phytomicrobiome communities and their fundamental knowledge about plant-microbe interactions for developing plant probiotics.
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The current study assessed the nematicidal and plant growth promoting potential of metabolites produced by Streptomyces hydrogenans strain DH-16 on morphological and physiological activities in 60 days old Solanum lycopersicum plants grown under Meloidogyne incognita stress. M. incognita infestation altered the levels of various photosynthetic pigments, various stress markers, enzymatic and non-enzymatic antioxidants in S. lycopersicum plants grown under in-vivo conditions. However, treatment with culture cells, supernatant and extract produced by S. hydrogenans strain DH-16 significantly reduced the number of galls in M. incognita infested plants when compared with untreated M. incognita infected plants. Moreover, the culture cells/ supernatant/ extract remarkably lowered the levels of stress markers (Hydrogen peroxide and Malondialdehyde) in infected plants and enhanced the activities of non-enzymatic antioxidants (glutathione, tocopherol) and enzymatic antioxidants (Catalase, Superoxide dismutase, Ascorbate peroxidase, Guaiacol peroxidase, Gluatathione-S-transferase and Polyphenol oxidase) in metabolites treated M. incognita infected plants. The enhanced level of different photosynthetic attributes were also evaluated by studying gas exchange parameters and different plant pigments. Moreover, an increment in the content of phenolic compounds such as total phenols, anthocyanin and flavonoids were also reflected in treated and nematode infested plants. The present study also evaluated the microscopic analysis depicting cell viability, nuclear damage and hydrogen peroxide localization in differently treated plants. The outcome of the present study therefore endorses the efficacy of DH-16 as a potential biocontrol agent that help plants in mitigating M. incognita stress.
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Solanum lycopersicum , Tylenchoidea , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Peróxido de Hidrógeno/metabolismo , Solanum lycopersicum/metabolismo , Fenoles/metabolismo , Extractos Vegetales/metabolismo , Streptomyces , Tylenchoidea/metabolismoRESUMEN
Arsenic (As) is highly toxic metal (loid) that impairs plant growth and proves fatal towards human population. It disrupts physiological, biochemical and molecular attributes of plants associated with water/nutrient uptake, redox homeostasis, photosynthetic machineries, cell/membrane damage, and ATP synthesis. Numerous transcription factors are responsive towards As through regulating stress signaling, toxicity and resistance. Additionally, characterization of specific genes encoding uptake, translocation, detoxification and sequestration has also explained their underlying mechanisms. Arsenic within soil enters the food chain and cause As-poisoning. Plethora of conventional methods has been used since decades to plummet As-toxicity, but the success rate is quite low due to environmental hazards. Henceforth, exploration of effective and eco-friendly methods is aimed for As-remediation. With the technological advancements, we have enumerated novel strategies to address this concern for practicing such techniques on global scale. Novel strategies such as bioremediation, phytoremediation, mycorrhizae-mediated remediation, biochar, algal-remediation etc. possess extraordinary results. Moreover, nitric oxide (NO), a signaling molecule has also been explored in relieving As-stress through reducing oxidative damages and triggering antioxidative responses. Other strategies such as role of plant hormones (salicylic acid, indole-3-acetic acid, jasmonic acid) and micro-nutrients such as selenium have also been elucidated in As-remediation from soil. This has been observed through stimulated antioxidant activities, gene expression of transporters, defense genes, cell-wall modifications along with the synthesis of chelating agents such as phytochelatins and metallothioneins. This review encompasses the updated information about As toxicity and its remediation through novel techniques that serve to be the hallmarks for stress revival. We have summarised the genetic engineering protocols, biotechnological as well as nanotechnological applications in plants to combat As-toxicity.
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Arsénico , Contaminantes Ambientales , Contaminantes del Suelo , Antioxidantes/metabolismo , Arsénico/análisis , Biodegradación Ambiental , Contaminantes Ambientales/metabolismo , Humanos , Plantas/metabolismo , Suelo , Contaminantes del Suelo/análisisRESUMEN
Increasing inorganic fertilizer and pesticide use has been linked to increased health risks for humans and cattle, as well as substantial water and soil contamination. In recent years, vermicomposting has shown to be a viable alternative to chemical pesticides. Vermicompost and vermicompost products such as extract and leachate assist plants in a number of ways. According to recent studies, vermicompost extract (VCE), when used as a supplement, is thought to work as a growth and stress tolerance booster for plants. These liquid supplements also help to suppress a range of pests, such as root knot nematodes. In the present study, neem- and cattle dung-based vermicompost extracts of different concentrations (0, 20, 40, 60, 80 and 100%) were prepared and used for their application against nematode infection in tomato seedlings under laboratory conditions. Apart from its antagonistic action against Meloidogyne incognita, the influence of VCE on plant growth was investigated by analyzing its morphological characteristics in tomato seedlings infected and uninfected with M. incognita. Seeds were pre-soaked in VCE for the seed priming process before being allowed for germination. After 10 days of nematode inoculation, biochemical parameters like protein content, activity of antioxidative enzymes, non-enzymatic antioxidants, stress indices, photosynthetic pigments, proline content and secondary metabolites were also analyzed. The results revealed that neem-based VCE was fatal to second-stage juveniles, with an 82% mortality rate following exposure to the highest dose. When eggs were exposed to 100% VCE, 33.8% of hatching was suppressed, indicating that VCE had an antagonistic effect on nematode egg hatching. Further, all the morphological and biochemical parameters were significantly enhanced in VCE-treated tomato seedlings as compared to untreated seedlings. Stress indices were also found to be significantly lowered by the VCE treatments in the infected plants. The effect of VCE on seedling growth and physiology was shown to be concentration dependent. As a result, the current findings show that VCE has the potential to be used as a plant growth accelerator as well as an environmentally friendly biocontrol agent against nematode pathogenesis in tomato plants.
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Solanum lycopersicum , Tylenchoidea , Animales , Biomasa , Bovinos , Humanos , Extractos Vegetales/farmacología , PlantonesRESUMEN
Roots of Withania somnifera, an important medicinal herb, are prone to the infection of Meloidogyne incognita (a root parasitic nematode). The infection lowers the quality and quantity of plant material and poses a challenge in crop cultivation and obtaining desirable yield. In the present study, in vitro inhibitory activity of vermicompost leachate (Vcom-L) was assessed against % hatch and survival of M. incognita in a 96 h assay. Then, Vcom-L was used as soil supplement in combination with vermicompost (Vcom) to evaluate their nematode inhibitory and stress alleviating effect in W. somnifera, in a pot experiment. Root galling intensity and growth performance of nematode-stressed W. somnifera raised from seeds pre-soaked in distilled water (DW), Vcom-L, vermicompost tea (Vcom-T) and different dilutions of Vcom-L were assessed. We observed 79% suppression of egg hatching and 89% juvenile (J2) mortality after 96 h compared to control, at 100% concentration of Vcom-L. Significant reduction in gall formation with increase in growth parameters of seedlings was observed after combined application of Vcom (60% or 100%) + Vcom-L and was evident as enhancement in seedling biomass and contents of chlorophyll and protein. However, proline, total phenolics and malondialdehyde (MDA) content declined significantly in these combinations compared to the control (0% Vcom). Activity of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidise (APX), guaiacol peroxidise (GPX) and glutathione reductase (GR) declined with Vcom as well as Vcom + Vcom-L and corresponded with decline in the accumulation of reactive oxygen species in leaves. Further, 1:5 and 1:10 dilutions of Vcom-L in combination with Vcom (60%) proved beneficial in mitigating the nematode-induced stress in W. somnifera. Present results showed the potential of Vcom and Vcom-L in standardised combination as an effective strategy in controlling the pathogenicity of M. incognita in medicinal plants such as W. somnifera.
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Plantas Medicinales , Tylenchoidea , Withania , Animales , Hojas de la Planta , Plantones , SemillasRESUMEN
Cadmium (Cd) is considered to be one of the most toxic pollutants persistent in soil for thousands of years and is ranked on seventh position among all environmental pollutants. The higher concentration of Cd in plants inhibits their growth and metabolism and further enters the food chain. Cd toxicity initiates redox actions in plants by inducing oxidative stress through the production of free radicals. It alters mineral uptake by disturbing water potential or affects the microbial population in soils, opening and closing of stomata, transpiration, photosynthesis, antioxidant levels, sugar metabolism and productivities. It also causes chlorosis, mineral deficiencies, inhibition of nitrate reductase activity and ammonia assimilation in several plant species. The plants have adopted a number of mechanisms to facilitate reduction in the amount of ROS. They possess series of antioxidative defence responses to scavenge reactive oxygen species (ROS) levels. Furthermore, specific mechanisms such as such as efflux, immobilization, stabilization, complexation, sequestration and detoxification are generally observed to combat the Cd stresses. Moreover, endogenous phytohormonal signalling during stressed conditions within plants has also been focussed. Cd stimulates various hormonal signalling pathways and regulates many physiological processes in plants that in turn ameliorate Cd stress. Strikingly, phytohormones play an imperative role during signal transduction pathway along with regulating overall growth and development of plants under toxic conditions. Moreover, plant hormones boost antioxidant activities and plummet oxidative damage from plants along with maintaining cellular homeostasis. This review encompasses the ecotoxicological aspects of Cd within plants and plant responses to tackle such adversities.
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Contaminantes Ambientales , Contaminantes del Suelo , Antioxidantes/metabolismo , Cadmio/metabolismo , Contaminantes Ambientales/toxicidad , Estrés Oxidativo , Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Suelo , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidadRESUMEN
Communication among different species across kingdoms occurs through a chain of regulatory molecules that are transferred around cellular boundaries. These molecules are also crucial for defense, virulence, and pathogenesis. In the past, the transport of proteins in long distance communication was observed, but in the present era, the discovery of extracellular vesicles (EVs) has changed our understanding of molecular communication. EVs are not only involved in cell signaling and immunity but also can transfer information by sRNAs, forming a basis for interactions among a wide variety of organisms. Despite extensive research on EVs in other areas, their role in communication between plants and the plant microbiome has been lacking. EVs are potentially involved in protein trafficking along with the transport of lipids and nucleic acids. Interactions between hosts and their microbiomes may also be mediated by EVs, which can be involved in stress responses, immune surveillance and defense, virulence, and signaling, along with many metabolic activities within plant microbiomes. In this review, we have focused on recent information about the role of EVs and the molecules they transport between hosts and microbes. The connection between biofilms and the generation of EVs is also considered. These findings enhance our knowledge about plant-microbiome interactions in terms of immunity and virulence and challenge the conventional viewpoint of inter-kingdom signaling.
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Vesículas Extracelulares , Microbiota , Comunicación , Vesículas Extracelulares/metabolismo , Plantas , Transducción de SeñalRESUMEN
Nanotechnology is an avant-garde field of scientific research that revolutionizes technological advancements in the present world. It is a cutting-edge scientific approach that has undoubtedly a plethora of functions in controlling environmental pollutants for the welfare of the ecosystem. However, their unprecedented utilization and hysterical release led to a huge threat to the soil microbiome. Nanoparticles(NPs) hamper physicochemical properties of soil along with microbial metabolic activities within rhizospheric soils.Here in this review shed light on concentric aspects of NP-biosynthesis, types, toxicity mechanisms, accumulation within the ecosystem. However, the accrual of tiny NPs into the soil system has dramatically influenced rhizospheric activities in terms of soil properties and biogeochemical cycles. We have focussed on mechanistic pathways engrossed by microbes to deal with NPs.Also, we have elaborated the fate and behavior of NPs within soils. Besides, a piece of very scarce information on NPs-toxicity towards environment and rhizosphere communities is available. Therefore, the present review highlights ecological perspectives of nanotechnology and solutions to such implications. We have comprehend certain strategies such as avant-garde engineering methods, sustainable procedures for NP synthesis along with vatious regulatory actions to manage NP within environment. Moreover, we have devised risk management sustainable and novel strategies to utilize it in a rationalized and integrated manner. With this background, we can develop a comprehensive plan about NPs with novel insights to understand the resistance and toxicity mechanisms of NPs towards microbes. Henceforth, the orientation towards these issues would enhance the understanding of researchers for proper recommendation and promotion of nanotechnology in an optimized and sustainable manner.