Advancing crop disease resistance through genome editing: a promising approach for enhancing agricultural production.

Modern agriculture has encountered several challenges in achieving constant yield stability especially due to disease outbreaks and lack of long-term disease-resistant crop cultivars. In the past, disease outbreaks in economically important crops had a major impact on food security and the economy. On the other hand climate-driven emergence of new pathovars or changes in their host specificity further poses a serious threat to sustainable agriculture. At present, chemical-based control strategies are frequently used to control microbial pathogens and pests, but they have detrimental impact on the environment and also resulted in the development of resistant phyto-pathogens. As a replacement, cultivating engineered disease-resistant crops can help to minimize the negative impact of regular pesticides on agriculture and the environment. Although traditional breeding and genetic engineering have been instrumental in crop disease improvement but they have certain limitations such as labour intensity, time consumption, and low efficiency. In this regard, genome editing has emerged as one of the potential tools for improving disease resistance in crops by targeting multiple traits with more accuracy and efficiency. For instance, genome editing techniques, such as CRISPR/Cas9, CRISPR/Cas13, base editing, TALENs, ZFNs, and meganucleases, have proved successful in improving disease resistance in crops through targeted mutagenesis, gene knockouts, knockdowns, modifications, and activation of target genes. CRISPR/Cas9 is unique among these techniques because of its remarkable efficacy, low risk of off-target repercussions, and ease of use. Some primary targets for developing CRISPR-mediated disease-resistant crops are host-susceptibility genes (the S gene method), resistance genes (R genes) and pathogen genetic material that prevents their development, broad-spectrum disease resistance. The use of genome editing methods has the potential to notably ameliorate crop disease resistance and transform agricultural practices in the future. This review highlights the impact of phyto-pathogens on agricultural productivity. Next, we discussed the tools for improving disease resistance while focusing on genome editing. We provided an update on the accomplishments of genome editing, and its potential to improve crop disease resistance against bacterial, fungal and viral pathogens in different crop systems. Finally, we highlighted the future challenges of genome editing in different crop systems for enhancing disease resistance.

Uncovering the effect of waterlogging stress on plant microbiome and disease development: current knowledge and future perspectives.

Waterlogging is a constant threat to crop productivity and ecological biodiversity. Plants face multiple challenges during waterlogging stress like metabolic reprogramming, hypoxia, nutritional depletion, reduction in gaseous exchange, pH modifications, microbiome alterations and disease promotion all of which threaten plants survival. Due to global warming and climatic change, the occurrence, frequency and severity of flooding has dramatically increased posing a severe threat to food security. Thus, developing innovative crop management technologies is critical for ensuring food security under changing climatic conditions. At present, the top priority among scientists is to find nature-based solutions to tackle abiotic or biotic stressors in sustainable agriculture in order to reduce climate change hazards to the environment. In this regard, utilizing plant beneficial microbiome is one of the viable nature based remedial tool for mitigating abiotic stressors like waterlogging. Beneficial microbiota provides plants multifaceted benefits which improves their growth and stress resilience. Plants recruit unique microbial communities to shield themselves against the deleterious effects of biotic and abiotic stress. In comparison to other stressors, there has been limited studies on how waterlogging stress affects plant microbiome structure and their functional traits. Therefore, it is important to understand and explore how waterlogging alters plant microbiome structure and its implications on plant survival. Here, we discussed the effect of waterlogging stress in plants and its microbiome. We also highlighted how waterlogging stress promotes pathogen occurrence and disease development in plants. Finally, we highlight the knowledge gaps and areas for future research directions on unwiring how waterlogging affects plant microbiome and its functional traits. This will pave the way for identifying resilient microbiota that can be engineered to promote their positive interactions with plants during waterlogging stress.

Plant Immunity: At the Crossroads of Pathogen Perception and Defense Response.

Plants are challenged by different microbial pathogens that affect their growth and productivity. However, to defend pathogen attack, plants use diverse immune responses, such as pattern-triggered immunity (PTI), effector-triggered immunity (ETI), RNA silencing and autophagy, which are intricate and regulated by diverse signaling cascades. Pattern-recognition receptors (PRRs) and nucleotide-binding leucine-rich repeat (NLR) receptors are the hallmarks of plant innate immunity because they can detect pathogen or related immunogenic signals and trigger series of immune signaling cascades at different cellular compartments. In plants, most commonly, PRRs are receptor-like kinases (RLKs) and receptor-like proteins (RLPs) that function as a first layer of inducible defense. In this review, we provide an update on how plants sense pathogens, microbe-associated molecular patterns (PAMPs or MAMPs), and effectors as a danger signals and activate different immune responses like PTI and ETI. Further, we discuss the role RNA silencing, autophagy, and systemic acquired resistance as a versatile host defense response against pathogens. We also discuss early biochemical signaling events such as calcium (Ca2+), reactive oxygen species (ROS), and hormones that trigger the activation of different plant immune responses. This review also highlights the impact of climate-driven environmental factors on host-pathogen interactions.

Saffron, a Potential Bridge between Nutrition and Disease Therapeutics: Global Health Challenges and Therapeutic Opportunities.

Plants are an important source of essential bioactive compounds that not only have a beneficial role in human health and nutrition but also act as drivers for shaping gut microbiome. However, the mechanism of their functional attributes is not fully understood despite their significance. One such important plant is Crocus sativus, also known as saffron, which possesses huge medicinal, nutritional, and industrial applications like food and cosmetics. The importance of this plant is grossly attributed to its incredible bioactive constituents such as crocins, crocetin, safranal, picrocrocin, and glycosides. These bioactive compounds possess a wide range of therapeutic activities against multiple human ailments. Since a huge number of studies have revealed negative unwanted side effects of modern-day drugs, the scientific communities at the global level are investigating a large number of medicinal plants to explore natural products as the best alternatives. Taken into consideration, the available research findings indicate that saffron has a huge scope to be further explored to establish alternative natural-product-based drugs for health benefits. In this review, we are providing an update on the role of bioactive compounds of saffron as therapeutic agents (human disorders and antimicrobial activity) and its nutritional values. We also highlighted the role of omics and metabolic engineering tools for increasing the content of key saffron bioactive molecules for its mass production. Finally, pre-clinical and clinical studies seem to be necessary to establish its therapeutic potential against human diseases.

Revisiting the Role of Sensors for Shaping Plant Research: Applications and Future Perspectives.

Plant health monitoring is essential for understanding the impact of environmental stressors (biotic and abiotic) on crop production, and for tailoring plant developmental and adaptive responses accordingly. Plants are constantly exposed to different stressors like pathogens and soil pollutants (heavy metals and pesticides) which pose a serious threat to their survival and to human health. Plants have the ability to respond to environmental stressors by undergoing rapid transcriptional, translational, and metabolic reprogramming at different cellular compartments in order to balance growth and adaptive responses. However, plants' exceptional responsiveness to environmental cues is highly complex, which is driven by diverse signaling molecules such as calcium Ca2+, reactive oxygen species (ROS), hormones, small peptides and metabolites. Additionally, other factors like pH also influence these responses. The regulation and occurrence of these plant signaling molecules are often undetectable, necessitating nondestructive, live research approaches to understand their molecular complexity and functional traits during growth and stress conditions. With the advent of sensors, in vivo and in vitro understanding of some of these processes associated with plant physiology, signaling, metabolism, and development has provided a novel platform not only for decoding the biochemical complexity of signaling pathways but also for targeted engineering to improve diverse plant traits. The application of sensors in detecting pathogens and soil pollutants like heavy metal and pesticides plays a key role in protecting plant and human health. In this review, we provide an update on sensors used in plant biology for the detection of diverse signaling molecules and their functional attributes. We also discuss different types of sensors (biosensors and nanosensors) used in agriculture for detecting pesticides, pathogens and pollutants.

Trichoderma Inoculation Alleviates Cd and Pb-Induced Toxicity and Improves Growth and Physiology of Vigna radiata (L.).

Heavy metals (HMs) pose a serious threat to agricultural productivity. Therefore, there is a need to find sustainable approaches to combat HM stressors in agriculture. In this study, we isolated Trichoderma sp. TF-13 from metal-polluted rhizospheric soil, which has the ability to resist 1600 and 1200 µg mL-1 cadmium (Cd) and lead (Pb), respectively. Owing to its remarkable metal tolerance, this fungal strain was applied for bioremediation of HMs in Vigna radiata (L.). Strain TF-13 produced siderophore, salicylic acid (SA; 43.4 µg mL-1) and 2,3-DHBA (21.0 µg mL-1), indole-3-acetic acid, ammonia, and ACC deaminase under HM stressed conditions. Increasing concentrations of tested HM ions caused severe reduction in overall growth of plants; however, Trichoderma sp. TF-13 inoculation significantly (p ≤ 0.05) increased the growth and physiological traits of HM-treated V. radiata. Interestingly, Trichoderma sp. TF-13 improved germination rate (10%), root length (26%), root biomass (32%), and vigor index (12%) of V. radiata grown under 25 µg Cd kg-1 soil. Additionally, Trichoderma inoculation showed a significant (p ≤ 0.05) increase in total chlorophyll, chl a, chl b, carotenoid content, root nitrogen (N), and root phosphorus (P) of 100 µg Cd kg-1 soil-treated plants over uninoculated treatment. Furthermore, enzymatic and nonenzymatic antioxidant activities of Trichoderma inoculated in metal-treated plants were improved. For instance, strain TF-13 increased proline (37%), lipid peroxidation (56%), catalase (35%), peroxidase (42%), superoxide dismutase (27%), and glutathione reductase (39%) activities in 100 µg Pb kg-1 soil-treated plants. The uptake of Pb and Cd in root/shoot tissues was decreased by 34/39 and 47/38% in fungal-inoculated and 25 µg kg-1 soil-treated plants. Thus, this study demonstrates that stabilizing metal mobility in the rhizosphere through Trichoderma inoculation significantly reduced the detrimental effects of Cd and Pb toxicity in V. radiata and also enhanced development under HM stress conditions.

Understanding the mechanobiology of phytoacoustics through molecular Lens: Mechanisms and future perspectives.

BACKGROUND: How plants emit, perceive, and respond to sound vibrations (SVs) is a long-standing question in the field of plant sensory biology. In recent years, there have been numerous studies on how SVs affect plant morphological, physiological, and biochemical traits related to growth and adaptive responses. For instance, under drought SVs navigate plant roots towards water, activate their defence responses against stressors, and increase nectar sugar in response to pollinator SVs. Also, plants emit SVs during stresses which are informative in terms of ecological and adaptive perspective. However, the molecular mechanisms underlying the SV perception and emission in plants remain largely unknown. Therefore, deciphering the complexity of plant-SV interactions and identifying bonafide receptors and signaling players will be game changers overcoming the roadblocks in phytoacoustics. AIM OF REVIEW: The aim of this review is to provide an overview of recent developments in phytoacoustics. We primarily focuss on SV signal perception and transduction with current challenges and future perspectives. KEY SCIENTIFIC CONCEPTS OF REVIEW: Timeline breakthroughs in phytoacoustics have constantly shaped our understanding and belief that plants may emit and respond to SVs like other species. However, unlike other plant mechanostimuli, little is known about SV perception and signal transduction. Here, we provide an update on phytoacoustics and its ecological importance. Next, we discuss the role of cell wall receptor-like kinases, mechanosensitive channels, intracellular organelle signaling, and other key players involved in plant-SV receptive pathways that connect them. We also highlight the role of calcium (Ca2+), reactive oxygen species (ROS), hormones, and other emerging signaling molecules in SV signal transduction. Further, we discuss the importance of molecular, biophysical, computational, and live cell imaging tools for decoding the molecular complexity of acoustic signaling in plants. Finally, we summarised the role of SV priming in plants and discuss how SVs could modulate plant defense and growth trade-offs during other stresses.

Deciphering the role of mechanosensitive channels in plant root biology: perception, signaling, and adaptive responses.

MAIN CONCLUSION: Mechanosensitive channels are integral membrane proteins that rapidly translate extrinsic or intrinsic mechanical tensions into biological responses. They can serve as potential candidates for developing smart-resilient crops with efficient root systems. Mechanosensitive (MS) calcium channels are molecular switches for mechanoperception and signal transduction in all living organisms. Although tremendous progress has been made in understanding mechanoperception and signal transduction in bacteria and animals, this remains largely unknown in plants. However, identification and validation of MS channels such as Mid1-complementing activity channels (MCAs), mechanosensitive-like channels (MSLs), and Piezo channels (PIEZO) has been the most significant discovery in plant mechanobiology, providing novel insights into plant mechanoperception. This review summarizes recent advances in root mechanobiology, focusing on MS channels and their related signaling players, such as calcium ions (Ca2+), reactive oxygen species (ROS), and phytohormones. Despite significant advances in understanding the role of Ca2+ signaling in root biology, little is known about the involvement of MS channel-driven Ca2+ and ROS signaling. Additionally, the hotspots connecting the upstream and downstream signaling of MS channels remain unclear. In light of this, we discuss the present knowledge of MS channels in root biology and their role in root developmental and adaptive traits. We also provide a model highlighting upstream (cell wall sensors) and downstream signaling players, viz., Ca2+, ROS, and hormones, connected with MS channels. Furthermore, we highlighted the importance of emerging signaling molecules, such as nitric oxide (NO), hydrogen sulfide (H2S), and neurotransmitters (NTs), and their association with root mechanoperception. Finally, we conclude with future directions and knowledge gaps that warrant further research to decipher the complexity of root mechanosensing.

ROS interplay between plant growth and stress biology: Challenges and future perspectives.

In plants, reactive oxygen species (ROS) have emerged as a multifunctional signaling molecules that modulate diverse stress and growth responses. Earlier studies on ROS in plants primarily focused on its toxicity and ROS-scavenging processes, but recent findings are offering new insights on its role in signal perception and transduction. Further, the interaction of cell wall receptors, calcium channels, HATPase, protein kinases, and hormones with NADPH oxidases (respiratory burst oxidase homologues (RBOHs), provides concrete evidence that ROS regulates major signaling cascades in different cellular compartments related to stress and growth responses. However, at the molecular level there are many knowledge gaps regarding how these players influence ROS signaling and how ROS regulate them during growth and stress events. Furthermore, little is known about how plant sensors or receptors detect ROS under various environmental stresses and induce subsequent signaling cascades. In light of this, we provided an update on the role of ROS signaling in plant growth and stress biology. First, we focused on ROS signaling, its production and regulation by cell wall receptor like kinases. Next, we discussed the interplay between ROS, calcium and hormones, which forms a major signaling trio regulatory network of signal perception and transduction. We also provided an overview on ROS and nitric oxide (NO) crosstalk. Furthermore, we emphasized the function of ROS signaling in biotic, abiotic and mechanical stresses, as well as in plant growth and development. Finally, we conclude by highlighting challenges and future perspectives of ROS signaling in plants that warrants future investigation.

A review on anti-nutritional factors: unraveling the natural gateways to human health.

Humans are constantly facing multiple health challenges from both communicable and non-communicable diseases that significantly affect their health. Additionally, drug resistance or failure has made the situation even worse and poses serious challenges for researchers to develop new drugs. Hence, to address these problems, there is an urgent need to discover and develop timely and long-term-based therapeutic treatments from different sources. One such approach is harnessing the potential of plant secondary metabolites. Plants have been utilized for therapeutic purposes in addition to being used for nutritional benefits. In the last two decades, plant-based drug developments have been one of the effective means of treating human diseases owing to their multiple functions. More recently, anti-nutritional factors (ANFs) have emerged as one of the important targets for novel plant-based drug development due to their multifaceted and potential pharmacological properties. However, their anti-nutritional properties have been the major setback for their limited success in the pharmacological sector. In this review, we provide an overview of ANFs and their beneficial roles in preventing human diseases with multiple case studies. We also highlight the recent developments and applications of ANFs in the food industry, agriculture, and pharmaceutics with future perspectives. Furthermore, we evaluate meta-analyses on ANFs from the last 30 years in relation to their function in human health benefits. This review is an endeavor to reevaluate the merit of these natural compounds and explore their potential for both human and animal health.

Plant beneficial microbiome a boon for improving multiple stress tolerance in plants.

Beneficial microbes or their products have been key drivers for improving adaptive and growth features in plants under biotic and abiotic stress conditions. However, the majority of these studies so far have been utilized against individual stressors. In comparison to individual stressors, the combination of many environmental stresses that plants experience has a greater detrimental effect on them and poses a threat to their existence. Therefore, there is a need to explore the beneficial microbiota against combined stressors or multiple stressors, as this will offer new possibilities for improving plant growth and multiple adaptive traits. However, recognition of the multifaceted core beneficial microbiota from plant microbiome under stress combinations will require a thorough understanding of the functional and mechanistic facets of plant microbiome interactions under different environmental conditions in addition to agronomic management practices. Also, the development of tailored beneficial multiple stress tolerant microbiota in sustainable agriculture necessitates new model systems and prioritizes agricultural microbiome research. In this review, we provided an update on the effect of combined stressors on plants and their microbiome structure. Next, we discussed the role of beneficial microbes in plant growth promotion and stress adaptation. We also discussed how plant-beneficial microbes can be utilized for mitigating multiple stresses in plants. Finally, we have highlighted some key points that warrant future investigation for exploring plant microbiome interactions under multiple stressors.

The chromosome-scale genome assembly of cluster bean provides molecular insight into edible gum (galactomannan) biosynthesis family genes.

Cluster bean (Cyamopsis tetragonoloba (L.) Taub 2n = 14, is commonly known as Guar. Apart from being a vegetable crop, it is an abundant source of a natural hetero-polysaccharide called guar gum or galactomannan. Here, we are reporting a chromosome-scale reference genome assembly of a popular cluster bean cultivar RGC-936, by combining sequencing data from Illumina, 10X Genomics, Oxford Nanopore technologies. An initial assembly of 1580 scaffolds with an N50 value of 7.12 Mb was generated and these scaffolds were anchored to a high density SNP linkage map. Finally, a genome assembly of 550.31 Mb (94% of the estimated genome size of ~ 580 Mb (through flow cytometry) with 58 scaffolds was obtained, including 7 super scaffolds with a very high N50 value of 78.27 Mb. Phylogenetic analysis using single copy orthologs among 12 angiosperms showed that cluster bean shared a common ancestor with other legumes 80.6 MYA. No evidence of recent whole genome duplication event in cluster bean was found in our analysis. Further comparative transcriptomics analyses revealed pod-specific up-regulation of genes encoding enzymes involved in galactomannan biosynthesis. The high-quality chromosome-scale cluster bean genome assembly will facilitate understanding of the molecular basis of galactomannan biosynthesis and aid in genomics-assisted improvement of cluster bean.

Chromium Toxicity in Plants: Signaling, Mitigation, and Future Perspectives.

Plants are very often confronted by different heavy metal (HM) stressors that adversely impair their growth and productivity. Among HMs, chromium (Cr) is one of the most prevalent toxic trace metals found in agricultural soils because of anthropogenic activities, lack of efficient treatment, and unregulated disposal. It has a huge detrimental impact on the physiological, biochemical, and molecular traits of crops, in addition to being carcinogenic to humans. In soil, Cr exists in different forms, including Cr (III) "trivalent" and Cr (VI) "hexavalent", but the most pervasive and severely hazardous form to the biota is Cr (VI). Despite extensive research on the effects of Cr stress, the exact molecular mechanisms of Cr sensing, uptake, translocation, phytotoxicity, transcript processing, translation, post-translational protein modifications, as well as plant defensive responses are still largely unknown. Even though plants lack a Cr transporter system, it is efficiently accumulated and transported by other essential ion transporters, hence posing a serious challenge to the development of Cr-tolerant cultivars. In this review, we discuss Cr toxicity in plants, signaling perception, and transduction. Further, we highlight various mitigation processes for Cr toxicity in plants, such as microbial, chemical, and nano-based priming. We also discuss the biotechnological advancements in mitigating Cr toxicity in plants using plant and microbiome engineering approaches. Additionally, we also highlight the role of molecular breeding in mitigating Cr toxicity in sustainable agriculture. Finally, some conclusions are drawn along with potential directions for future research in order to better comprehend Cr signaling pathways and its mitigation in sustainable agriculture.

Exploring the Potential of Multiomics and Other Integrative Approaches for Improving Waterlogging Tolerance in Plants.

Soil flooding has emerged as a serious threat to modern agriculture due to the rapid global warming and climate change, resulting in catastrophic crop damage and yield losses. The most detrimental effects of waterlogging in plants are hypoxia, decreased nutrient uptake, photosynthesis inhibition, energy crisis, and microbiome alterations, all of which result in plant death. Although significant advancement has been made in mitigating waterlogging stress, it remains largely enigmatic how plants perceive flood signals and translate them for their adaptive responses at a molecular level. With the advent of multiomics, there has been significant progress in understanding and decoding the intricacy of how plants respond to different stressors which have paved the way towards the development of climate-resistant smart crops. In this review, we have provided the overview of the effect of waterlogging in plants, signaling (calcium, reactive oxygen species, nitric oxide, hormones), and adaptive responses. Secondly, we discussed an insight into past, present, and future prospects of waterlogging tolerance focusing on conventional breeding, transgenic, multiomics, and gene-editing approaches. In addition, we have also highlighted the importance of panomics for developing waterlogging-tolerant cultivars. Furthermore, we have discussed the role of high-throughput phenotyping in the screening of complex waterlogging-tolerant traits. Finally, we addressed the current challenges and future perspectives of waterlogging signal perception and transduction in plants, which warrants future investigation.

Unraveling the Variability of Essential Oil Composition in Different Accessions of Bunium persicum Collected from Different Temperate Micro-Climates.

The present investigation was performed to evaluate the variability of the essential oil composition present in the seed extract of Kala zeera (Bunium persicum Bioss.) obtained from different geographical zones of Northwestern-Himalayan using Gas Chromatography-Mass Spectrum (GC-MS). The results of the GC-MS analysis revealed significant differences in the essential oil content. Significant variability was observed in the chemical constituents of the essential oils mainly for p-cymene, D-limonene, Gamma-terpinene, Cumic aldehyde and 1, 4-p-menthadien-7-al. Among these compounds, the highest average percentage across the locations was observed for gamma-terpinene (32.08%) which was followed by cumic aldehyde (25.07%), and 1, 4-p-menthadien-7-al (15.45%). Principal component analysis (PCA) also grouped the 4 highly significant compounds i.e., p-Cymene, Gamma-Terpinene, Cumic aldehyde, and 1,4-p-Menthadien-7-al into same cluster which are mainly distributed in Shalimar Kalazeera-1, and Atholi Kishtwar zones. The highest value of gamma-terpinene was recorded in Atholi accession (40.66%). However, among climatic zones Zabarwan Srinagar and Shalimar Kalazeera-1 was found to have highly positive significant correlation (0.99). The cophenetic correlation coefficient (c) was found to be 0.8334 during hierarchical clustering for 12 essential oil compounds showing that our results are highly correlated. Network analysis also showed the overlapping pattern and similar interaction between the 12 compounds as shown by hierarchical clustering analysis. From the results, it could be concluded that existence of variability among the various bioactive compounds of B. persicum which are probably to be incorporated to the potential list of drugs and may serve as good genetic source for various modern breeding programs.

Plant Microbiome: An Ocean of Possibilities for Improving Disease Resistance in Plants.

Plant diseases pose a serious threat to crop production and the agricultural economy across the globe. Currently, chemical pesticides are frequently employed to combat these infections, which cause environmental toxicity and the emergence of resistant pathogens. Moreover, the genetic manipulation of plant defense pathways and the breeding of resistant genes has attained limited success due to the rapid evolution of pathogen virulence and resistance, together with host range expansion. Additionally, due to climate change and global warming, the occurrence of multiple stresses during disease outbreak has further impacted overall crop growth and productivity, posing a serious threat to food security. In this regard, harnessing the plant beneficial microbiome and its products can provide novel avenues for disease resistance in addition to boosting agricultural output, soil fertility and environmental sustainability. In plant-beneficial microbiome interactions, induced systemic resistance (ISR) has emerged as a key mechanism by which a beneficial microbiome primes the entire plant system for better defense against a wide range of phytopathogens and pests. In this review, we provide the recent developments on the role of plant beneficial microbiomes in disease resistance. We also highlight knowledge gaps and discuss how the plant immune system distinguishes pathogens and beneficial microbiota. Furthermore, we provide an overview on how immune signature hormones, such as salicylic acid (SA), jasmonic acid (JA) and ethylene (ET), shape plant beneficial microbiome. We also discuss the importance of various high-throughput tools and their integration with synthetic biology to design tailored microbial communities for disease resistance. Finally, we conclude by highlighting important themes that need future attention in order to fill the knowledge gaps regarding the plant immune system and plant-beneficial-microbiome-mediated disease resistance.

Glutathione improves low temperature stress tolerance in pusa sheetal cultivar of Solanum lycopersicum.

To investigate the impact of Glutathione (GSH) in mitigating low-temperature stress in Pusa Sheetal cv. of Solanum lycopersicum and imparting low-temperature tolerance by evaluating the different physiological responses. The plant under research was also being studied for its growth and stress tolerance. Low temperatures (LT) stress was applied to seedlings with or without GSH application 12 h before LT stress (prophylactic dose), after 12 h-LT (preemptive dose), and post 12-h recovery (curative dose). Different concentrations of GSH [0, G1 (0.5 mM), G2 (1 mM) and G3 (2 mM)] against LT stress were used. Antioxidant activities, photosynthesis, growth, and stress tolerance indices were quantified. LT stress caused an oxidative burst in S. lycopersicum seedlings of the Pusa Sheetal cv. as indicated by increased peroxidation of lipids and H2O2 concentration. Glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities were enhanced. The best concentration was G2 (1 mM), which resulted in a rise in antioxidant activity. Moreover, a decline in lipid peroxidation and H2O2 levels was also seen. The purpose of this study is to identify the role of GSH in reducing LT stress and to find the best dose concentration. This is the first report to assess the GSH-mediated LT stress tolerance in S. lycopersicum (Pusa Sheetal cv.). Therefore, exogenous GSH application of optimal concentration of GSH to LT stressed S. lycopersicum can be an effective approach for augmenting the plant detoxification system and promoting its growth and development.

Nitric oxide and spermine revealed positive defense interplay for the regulation of the chromium toxicity in soybean (Glycine max L.).

Current investigation demonstrated that chromium (Cr) toxicity affects adversely on the normal growth of soybean plants. However, the seed priming with nitric oxide (NO; 100 µM), and spermine (Spm; 0.01 Mm) can significantly alleviate the Cr toxicity in soybean plant. Herein, the hydroponic experiment was conducted to observe the individual as well as the interactive behavior of NO, and Spm on the various morpho-physiological and, biochemical parameters in soybean such as plant growth, plant height, seed germination indices, photosynthesis-related indices such as chlorophyll biosynthesis, PS system II, nutrient uptake of soybean seedlings against Cr (VI) toxicity. Our outcomes deliberated that the alone treatment of NO, and Spm cause a significant improvement in seed germination ratio, photosynthetic pigments, and biomass of plants by restricting Cr uptake; while NO + Spm treatment being more effective in the improvement of soybean growth relative to their individual treatment under Cr stress. Relative to alone treatment of NO, and Spm, the combined treatment significantly modulated the antioxidant activities, and lowered the ROS accumulation, and electrolyte leakage. In addition, seed priming with NO, and Spm mitigate the Cr-induced toxicity by reducing Cr uptake and stimulating the antioxidative defense mechanisms. Hence, these findings confirmed the positive defense interplay of the NO and Spm in the modulation of the Cr tolerance in soybean. However, the underlying defense mechanism of these synergetic effects needs to be further explored.

Thiamin stimulates growth, yield quality and key biochemical processes of cauliflower (Brassica oleracea L. var. Botrytis) under arid conditions.

Thiamin is a crucial vitamin with a vast variety of anti-oxidative and physiological roles in plants subjected to abiotic stresses. We examined the efficiency of foliar-applied thiamin (50 and 100 mM) on growth, yield quality and key-biochemical characteristics of two cultivars (FD1 and FD3) of cauliflower (Brassica oleracea L.) under water-deficit stress. Water stress at the rate of 50% field capacity (F.C.) markedly decreased the plant biomass, leaf total phenolics and ascorbic acid (AsA) contents. In contrast, drought-induced increase was noted in the leaf [hydrogen peroxide (H2O2), AsA, proline, malondialdehyde (MDA), glycinebetaine (GB), total soluble proteins and oxidative defense system in terms of high activities of peroxidase (POD), and catalase (CAT) enzymes] and the inflorescence (total phenolics, proline, GB, MDA, H2O2, and activities of SOD and CAT enzymes) characteristics of cauliflower. However, foliar-applied thiamin significantly improved growth and physio-biochemical attributes except leaf and inflorescence MDA and H2O2 contents of both cauliflower cultivars under water stress. Overall, application of thiamin enhanced the plant growth may be associated with suppressed reactive oxygen species (ROS) and upregulated antioxidants defense system of cauliflower.

Harnessing plant microbiome for mitigating arsenic toxicity in sustainable agriculture.

Heavy metal toxicity has become an impediment to agricultural productivity, which presents major human health concerns in terms of food safety. Among them, arsenic (As) a non-essential heavy metal has gained worldwide attention because of its noxious effects on agriculture and public health. The increasing rate of global warming and anthropogenic activities have promptly exacerbated As levels in the agricultural soil, thereby causing adverse effects to crop genetic and phenotypic traits and rendering them vulnerable to other stresses. Conventional breeding and transgenic approaches have been widely adapted for producing heavy metal resilient crops; however, they are time-consuming and labor-intensive. Hence, finding new mitigation strategies for As toxicity would be a game-changer for sustainable agriculture. One such promising approach is harnessing plant microbiome in the era of 'omics' which is gaining prominence in recent years. The use of plant microbiome and their cocktails to combat As metal toxicity has gained widespread attention, because of their ability to metabolize toxic elements and offer an array of perquisites to host plants such as increased nutrient availability, stress resilience, soil fertility, and yield. A comprehensive understanding of below-ground plant-microbiome interactions and their underlying molecular mechanisms in exhibiting resilience towards As toxicity will help in identifying elite microbial communities for As mitigation. In this review, we have discussed the effect of As, their accumulation, transportation, signaling, and detoxification in plants. We have also discussed the role of the plant microbiome in mitigating As toxicity which has become an intriguing research frontier in phytoremediation. This review also provides insights on the advancements in constructing the beneficial synthetic microbial communities (SynComs) using microbiome engineering that will facilitate the development of the most advanced As remedial tool kit in sustainable agriculture.