Browsing by Author "Pareek, Ashwani"

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Analysis of a salinity induced BjSOS3 protein from Brassica indicate it to be structurally and functionally related to its ortholog from Arabidopsis
(Elsevier, 2011) Kushwaha, Hemant R.; Kumar, Gautam; Verma, Praveen K.; Singla-Pareek, Sneh L.; Pareek, Ashwani
Arabidopsis has been a favorite model system for plant biologist. It is anticipated that comparative analysis of this plant with other members of Brassicaceae may aid in identification of orthologs playing role as key genetic determinants for salinity response. In this endeavor, we have recently identified SOS family members from Brassica juncea in our laboratory and reported their salinity responsive transcriptional induction in seedlings of various diploid and amphidiploids species. In the present study, we have carried out detailed time kinetics for BjSOS3 expression in a salinity tolerant B. juncea var. CS52. Transcript analysis at the sensitive growth stages of plants viz. seedling and reproductive stage indicated clear differential transcriptional regulation of BjSOS3 under non-induced as well as salinity induced conditions in a time and organ specific manner, mirroring their respective tolerance physiology. Similar to its ortholog from Arabidopsis thaliana, the modeled BjSOS3 protein show typical features of a Ca(2+) binding protein with four conserved EF-hands. We have also attempted to study the binding of SOS3 protein with the modeled SOS2 protein. It has been established that SOS3 protein senses Ca(2+) though the binding is very weak; we show the down regulation of BjSOS3 mRNA in presence of calcium chelator - EGTA under the various stress conditions including ABA. In situ localization of BjSOS3-GFP fusion protein in onion peel has shown its presence strongly in plasma membrane as well as cytosol. The leads presented in the paper will assist in understanding and establishing the SOS signaling machinery in B. juncea.
Can we secure food and nutrition through crop innovation ?
(John Wiley & Sons, 2025) Pareek, Ashwani; Gupta, Kapuganti Jagadis; Singla-Pareek, Sneh L.; Foyer, Christine H.
Climate change poses an existential challenge to global food and nutritional security by disrupting agricultural systems, altering crop yields, and affecting the availability of essential nutrients. Increasing temperatures, erratic rainfall patterns, and a greater frequency of extreme weather events negatively impact crop productivity, threatening the stability of food supply chains. Additionally, climate-induced stresses such as drought, salinity, and heat not only reduce yield quantity but also affect the nutritional composition of staple crops, potentially exacerbating micronutrient deficiencies. Addressing these challenges necessitates a multi-faceted approach, integrating genetic improvements, sustainable agricultural practices, and the development of climate-resilient crops that can thrive under adverse conditions. This special issue on ‘Food and Nutritional Security' brings together state-of-the-art reviews by experts and cutting-edge studies that highlight the importance of current research in crop science. The reviews and case studies that are contained in this volume provide a concise overview of the field, acknowledging current gaps in knowledge, while examining the potential of genetic innovations, sustainable agronomic practices, and biotechnological advancements in addressing food security challenges.
Cross-species expression of OsDJ-1C from rice enhances tolerance to salinity and drought stress in tomato
(Elsevier B.V., 2026) Mishra, Manjari; Chatterjee, Yajnaseni; Gupta, Brijesh Kumar; Tomar, Surabhi; Babuta, Priyanka; Gupta, Kapuganti Jagadis; Pareek, Ashwani; Singla-Pareek, Sneh Lata
Abiotic stresses such as salinity and drought induce the accumulation of methylglyoxal (MG), a highly cytotoxic dicarbonyl compound that disrupts cellular metabolism in plants. MG detoxification is primarily mediated by the glutathione-dependent glyoxalase pathway, classically comprising the enzymes glyoxalase I and II. In contrast, glyoxalase III (GLYIII) catalyzes detoxification of MG in a single-step without requiring glutathione. In the present study, we investigated the functional role of OsDJ-1C, a rice GLYIII enzyme, by heterologous overexpression in tomato (Solanum lycopersicum). Transgenic lines exhibited significantly enhanced stress tolerance through a more efficient antioxidant defense mechanism under stress conditions. This improvement was driven by increased GLYIII-mediated detoxification of MG, leading to effective suppression of reactive oxygen species (ROS) accumulation. Reduced ROS levels in the overexpression lines resulted in greater internal oxygen availability and enhanced cellular respiration than wild-type plants. Furthermore, transgenic plants maintained higher pyruvate levels than the wild-type controls, thereby sustaining tricarboxylic acid (TCA) cycle flux and ATP production under stress. Overall, these findings reveal a conserved, cross-species function of OsDJ-1C in enhancing abiotic stress tolerance emphasizing its relevance for improving agricultural sustainability and food security under changing climatic conditions.
Exploring the synergistic effects of drought and heat stress on chickpea seed development: Insights into nutritional quality and seed yield
(Elsevier B.V., 2024) Awasthi, Rashmi; Devi, Poonam; Jha, Uday Chand; Sharma, Kamal Dev; Roorkiwal, Manish; Kumar, Sanjeev; Pareek, Ashwani; Siddique, Kadambot H.M.; Prasad, PV Vara; Parida, Swarup K.; Nayyar, Harsh
Growing chickpea (Cicer arietinum L.) faces significant challenges due to rising temperatures and drought stress, particularly during the reproductive and seed-filling phases. This study investigated the single and joint impacts of drought and heat stress on seed development, focusing on the responses of drought-tolerant (DT) and droughtsensitive (DS) chickpea genotypes. Initially raised in an outdoor environment (mean day and night temperature of 27 and 16±1 ◦C, respectively, light intensity of 1230–1440 µmol m− 2 s − 1 , relative humidity of 70/43 %) until seed filling (around 110–113 days after sowing) commenced. The plants were subsequently exposed to single or combined heat and drought stress under controlled conditions until maturity. Control pots were maintained at day and night temperature of 25 and 15 ◦C, respectively with 500 µmol m− 2 s − 1 light, 60–65 % RH, and regular irrigation, and drought-stressed pots were kept at 50 % field capacity under the same conditions of light and humidity. Heat stress in pots was gradually increased to 32(day)/20 ◦C (night) under regular irrigation, while combined stress pots experienced both drought (50 % field capacity) and heat stress conditions 32(day)/20 ◦C (night) under the same light and humidity conditions with irrigation. All stress treatments adversely affected cell membranes, photosynthesis, and water regulation, with more pronounced effects under combined stress. While heat stress increased stomatal conductance, drought and combined stress significantly reduced it. Seed filling rate and duration decreased under all stress conditions, especially combined stress. The stresses in combination severely reduced seed weight and pod numbers compared to individual stresses. Enzyme activities involved in starch and sucrose synthesis and hydrolysis substantially decreased under the combined stress. Seed composition elements (starch, storage proteins, sugars, fat, crude fiber, and ash) exhibited significant reductions across all stress treatments, particularly for the combined stress. Thus, under combined stresses, starch, proteins, and soulube sugars were markedly decreased to 13–20 %, 6.4–12.4 %, and 3–5 % in seeds, compared to 37–39 %, 21–24 %, and 6 % in control seeds. The DT genotype outperformed the DS genotype for all traits under individual and combined stress conditions. Principal component analysis revealed a complex interplay among various physiological responses (membrane damage, chlorophyll, chlorophyll fluorescence, relative leaf water content, and stomatal conductance), seed yield, and seed composition under the combined stress. This study highlighted that combined heat and drought stress severely impacted chickpea yield and nutritional traits, such as seed starch and protein content, compared to individual stresses underscoring the need to develop cultivars tolerant to this stress combination.
Gaining acceptance of novel plant breeding technologies
(Elsevier B.V., 2021) Anders, Sven; Cowling, Wallace; Pareek, Ashwani; Gupta, Kapuganti Jagadis; Singla-Pareek, Sneh L.; Foyer, Christine H.
Ensuring the sustainability of agriculture under climate change has led to a surge in alternative strategies for crop improvement. Advances in integrated crop breeding, social acceptance, and farm-level adoption are crucial to address future challenges to food security. Societal acceptance can be slow when consumers do not see the need for innovation or immediate benefits. We consider how best to address the issue of social licence and harmonised governance for novel gene technologies in plant breeding. In addition, we highlight optimised breeding strategies that will enable long-term genetic gains to be achieved. Promoted by harmonised global policy change, innovative plant breeding can realise high and sustainable productivity together with enhanced nutritional traits.
Lactate dehydrogenase superfamily in rice and Arabidopsis: Understanding the molecular evolution and structural diversity
(MDPI AG, 2023) Chatterjee, Yajnaseni; Bhowal, Bidisha; Gupta, Kapuganti Jagadis; Pareek, Ashwani; Singla-Pareek, Sneh Lata
Lactate/malate dehydrogenases (Ldh/Maldh) are ubiquitous enzymes involved in the central metabolic pathway of plants and animals. The role of malate dehydrogenases in the plant system is very well documented. However, the role of its homolog L-lactate dehydrogenases still remains elusive. Though its occurrence is experimentally proven in a few plant species, not much is known about its role in rice. Therefore, a comprehensive genome-wide in silico investigation was carried out to identify all Ldh genes in model plants, rice and Arabidopsis, which revealed Ldh to be a multigene family encoding multiple proteins. Publicly available data suggest its role in a wide range of abiotic stresses such as anoxia, salinity, heat, submergence, cold and heavy metal stress, as also confirmed by our qRT-PCR analysis, especially in salinity and heavy metal mediated stresses. A detailed protein modelling and docking analysis using Schrodinger Suite reveals the presence of three putatively functional L-lactate dehydrogenases in rice, namely OsLdh3, OsLdh7 and OsLdh9. The analysis also highlights the important role of Ser-219, Gly-220 and His-251 in the active site geometry of OsLdh3, OsLdh7 and OsLdh9, respectively. In fact, these three genes have also been found to be highly upregulated under salinity, hypoxia and heavy metal mediated stresses in rice.
Modulation of nitric oxide mediated by Phytoglobin1 plays a role in salinity tolerance via reduced nitro-oxidative stress in Arabidopsis
(Elsevier B.V., 2026) Swain, Jagannath; Babuta, Priyanka; Pandey, Sonika; Samant, Sanjib Bal; Yadav, Reena; Manbir; Hebelstrup, Kim H.; Igamberdiev, Abir U.; Singla-Pareek, Sneh Lata; Pareek, Ashwani; Gupta, Kapuganti Jagadis
Salinity is one of the major abiotic stresses that induces nitro-oxidative stress, which severely diminishes plant growth, development, and survival by altering various metabolic pathways. Phytoglobin (Pgb) is a nitric oxide (NO) scavenger that plays an important role in various stresses. However, the role of differential levels of phytoglobin1 in regulation of salinity stress induced nitro-oxidative stress in plants is not known. Here we characterized the role of Pgb-mediated NO in salinity tolerance by regulation of nitro-oxidative stress using Pgb1 overexpressing (Pgb1-OE) and silencing lines (pgb1-AS) of Arabidopsis. We found that imposing salinity leads to enhanced expression of Pgb1. NO measurement by both chemiluminescence and DAF-FM-DA suggested that salinity stress induces NO production. Pgb1-OE lines showed reduced levels of NO which is accompanied by reduced ROS, superoxide and H2O2 levels. On the contrary, pgb1-AS lines showed increased NO and ROS under salt stress. Further, gene expression analysis revealed an elevated expression of antioxidant genes in Pgb1-OE line in comparison to WT and pgb1-AS lines under salinity stress. Pgb1-OE lines showed enhanced survival which is correlated with reduced peroxynitrite and tyrosine nitration and opposing effect was observed in pgb1-AS lines along with increased cell death. Taken together, our study revealed that modulation of Pgb1 enhances tolerance to salinity-induced nitro-oxidative stress.
Nitric oxide, energy and redox-dependent responses to hypoxia
(Oxford University Press, 2024) Samant, Sanjib Bal; Yadav, Nidhi; Swain, Jagannath; Joseph, Josepheena; Kumari, Aprajita; Praveen, Afsana; Sahoo, Ranjan Kumar; Manjunatha, Girigowda; Seth, Chandra Shekar; Singla-Pareek, Sneh Lata; Foyer, Christine H; Pareek, Ashwani; Gupta, Kapuganti Jagadis
Hypoxia occurs when the oxygen levels fall below the levels required for mitochondria to support respiration. Regulated hypoxia is associated with quiescence, particularly in storage organs (seeds) and stem cell niches. In contrast, environmentally-induced hypoxia poses significant challenges for metabolically-active cells that are adapted to aerobic respiration. The perception of oxygen availability through cysteine oxidases, which function as oxygen-sensing enzymes in plants that control the N-degron pathway, and the regulation of hypoxia-responsive genes and processes is essential to survival. Functioning together with reactive oxygen species (ROS), particularly hydrogen peroxide and reactive nitrogen species (RNS), such as nitric oxide (•NO), nitrogen dioxide (•NO2), S‐nitrosothiols (SNOs), and peroxynitrite (ONOO−), hypoxia signaling pathways trigger anatomical adaptations such as formation of aerenchyma, mobilization of sugar reserves for anaerobic germination, formation of aerial adventitious roots and hyponastic response. NO and hydrogen peroxide (H2O2) participate in local and systemic signaling pathways that facilitate acclimation to changing energetic requirements, controlling glycolytic fermentation, the GABA shunt and amino acid synthesis. NO enhances antioxidant capacity and contributes to the recycling of redox equivalents energy metabolism through the phytoglobin (Pgb)-NO cycle. Here, we summarize current knowledge, highlighting the central role of NO and redox regulation in adaptive responses that prevent hypoxia-induced death in challenging conditions such as flooding.
OsLdh3 interacts with OsGAPC3 and OsLos2 to maintain the glycolytic continuum for tolerance to multiple abiotic stresses in rice
(Oxford University Press, 2026) Chatterjee, Yajnaseni; Babuta, Priyanka; Gupta, Kapuganti Jagadis; Pareek, Ashwani; Singla-Pareek, Sneh Lata
Lactate dehydrogenases are oxidoreductases present in almost all living organisms. They catalyze the interconversion of pyruvate and L-lactate with simultaneous oxidation of NADH and reduction of NAD+. Since their function remains largely unexplored in rice, in this study we deciphered the role of the rice lactate dehydrogenase, OsLdh3. OsLdh3 showed optimum enzyme activity at pH 6.6 for the forward reaction (pyruvate to L-lactate) and pH 9 for the reverse reaction (L-lactate to pyruvate). Protein-protein interaction studies revealed that OsLdh3 interacts with the glycolytic enzymes glyceraldehyde 3-phosphate dehydrogenaseC3 (OsGAPC3) and Enolase2 (OsLos2), suggesting its role in regulating glycolytic flux. Further, overexpression of OsLdh3 in rice showed enhanced abiotic stress tolerance by exhibiting elevated NAD+ levels and OsGAPC3 activity, thereby facilitating an improved glycolytic continuum and higher pyruvate accumulation. Consequently, these lines also showed increased mitochondrial respiration and ATP synthesis, and reduced reactive oxygen species (ROS) accumulation. Further, enhanced photosynthetic efficiency and reduced yield penalty of the stress-imposed OsLdh3 overexpression lines underscore its importance in crop productivity under adverse climatic conditions. Thus, our findings show that OsLdh3 enhances stress tolerance in rice by regulating redox homeostasis and respiration, reducing ROS levels, and maintaining energy balance. This makes OsLdh3 a promising candidate gene for developing climate-resilient rice cultivars with reduced yield gap.
Overexpression of phytoglobin1 in rice leads to enhanced nitrogen use efficiency via modulation of nitric oxide
(John Wiley & Sons, 2025) Samant, Sanjib Bal; Swain, Jagannath; Yadav, Nidhi; Yadav, Reena; Singh, Pooja; Rai, Preeti; Sheri, Vijay; Sreeman, Sheshshayee; Subramanyam, Rajagopal; Pareek, Ashwani; Gupta, Kapuganti Jagadis
Nitric oxide (NO) is one of the byproducts of nitrogen metabolism. Excess amount of NO is scavenged by phytoglobins. The role of phytoglobin mediated NO homoeostasis in modulation of nitrate transporters was investigated using NO scavenger cPTIO, phytoglobin overexpressing rice and Arabidopsis. Growing plants under low nitrate leads to generation of reduced levels of NO accompanied by elevated expression of high affinity transporters (HATs) such as NRT2.1, NRT2.3 and NRT2.4. Scavenging of NO by cPTIO under optimal nitrate caused enhanced HATs expression. Phytoglobin overexpressing Arabidopsis showed improved growth and enhanced expression of HATs under low nitrogen in comparison to WT. Pretreatment of optimal nitrate grown plants with NO scavenger cPTIO enhanced HATs expression and shifting of these primed plants from optimal to low nitrate leads to further elevation of HATs expression accompanied by enhanced nitrogen uptake and its accumulation with positive effect on growth. Phytoglobin overexpression in rice leads to enhanced HATs expression, improved growth, nitrogen accumulation under low nitrate. Pgb OE lines showed enhanced accumulation of amino acids. Taken together our results suggest an important role of phytoglobins in nitrogen uptake and assimilation.
Raising crops for dry and saline lands: Challenges and the way forward
(John Wiley & Sons, 2022) Singh, Anil Kumar; Gupta, Kapuganti Jagadis; Singla-Pareek, Sneh L.; Foyer, Christine H.; Pareek, Ashwani
Plants are continuously exposed to various environmental stresses. Of these, soil salinity and drought are considered to be the most important environmental stresses globally because they have a negative impact on plant growth and crop productivity. Drought and salinity thus threaten global food and nutritional security. The estimated annual global loss in crop production due to saline soils in irrigated areas is approximately US$27.3 billion (Qadir et al., 2014). Drought caused direct losses to the developing world's agriculture in the order of US$ 29 billion between 2005 and 2015 (FAO, 2018). Conversely, there is an increasing pressure to enhance agricultural production by 70% to feed a predicted increase in the world population of 9.7 billion by 2050. Hence, agriculture systems must become extremely productive and less wasteful throughout the world. Achieving this goal will be extremely challenging under the prevailing environmental conditions coupled with reductions in arable land and freshwater availability, together with climate change-induced environmental uncertainties. Over the past six decades, classical plant breeding technologies have played a major role in increasing crop performance and productivity. However, the consensus of scientific opinion is that most major crops have reached their maximum yield potential. Hence, the challenge for plant science is to develop improved crop varieties that can achieve sustainable higher yields with limited soil water availability and on saline soils. Recent developments in gene editing and innovative plant breeding technologies are crucial to the nature-based roadmap for sustainable agriculture intensification and climate resilience.
Seedling-stage salinity tolerance in rice: decoding the role of transcription factors
(John Wiley & Sons, 2022) Tiwari, Shalini; Nutan, Kamlesh Kant; Deshmukh, Rupesh; Sarsu, Fatma; Gupta, Kapuganti Jagadis; Singh, Anil K.; Singla-Pareek, Sneh L.; Pareek, Ashwani
Rice is an important staple food crop that feeds over half of the human population, particularly in developing countries. Increasing salinity is a major challenge for continuing rice production. Though rice is affected by salinity at all the developmental stages, it is most sensitive at the early seedling stage. The yield thus depends on how many seedlings can withstand saline water at the stage of transplantation, especially in coastal farms. The rapid development of ‘omics’ approaches has assisted researchers in identifying biological molecules that are responsive to salt stress. Several salinity-responsive quantitative trait loci (QTL) contributing to salinity tolerance have been identified and validated, making it essential to narrow down the search for the key genes within QTLs. Owing to the impressive progress of molecular tools, it is now clear that the response of plants towards salinity is highly complex, involving multiple genes, with a specific role assigned to the repertoire of transcription factors. Targeting the transcription factors for improving salinity tolerance can have an inbuilt advantage of influencing multiple downstream genes, which in turn can contribute towards tolerance to multiple stresses. This is the first comparative study for TF-driven salinity tolerance in contrasting rice cultivars at the seedling stage that shows how tolerant genotypes behave differently than sensitive ones in terms of stress tolerance. Understanding the complexity of salt-responsive transcription factor networks at the seedling stage will be helpful to alleviate crop resilience and prevent crop damage at an early growth stage in rice.
Sensing and signalling in plant stress responses: ensuring sustainable food security in an era of climate change
(John Wiley & Sons, 2020) Pareek, Ashwani; Joshi, Rohit; Gupta, Kapuganti Jagadis; Singla-Pareek, Sneh L.; Foyer, Christine
‘EMBO India Symposium ‘Sensing and signalling in plant stress response’ held in New Delhi, India, 15–17 April 2019 Agriculture in the 21stcentury faces multiple challenges from biotic and abiotic stresses, which impose major constraints on crop yield. Under field conditions, the combined or sequential occurrence of environmental stresses poses a serious threat to global food security. Plants exhibit plasticity in their responses to environmental stresses, which may be attributed to their genetic and/or epigenetic makeup. One of the major challenges facing plant biology today concerns how gene regulatory networks function to generate morphological and adaptive diversity. Gaining a better understanding of the responses of crop plants to environmental stresses will allow the identification of improved genetic markers to increase yield stability and enhance productivity over a wide range of growth conditions. The availability of high-throughput sequencing technologies provides an opportunity to uncover the genetic/epigenetic basis of plant stress responses and adaptation. Furthermore, dissection of the molecular mechanisms underlying resilience will help us understand how plants cope with extreme environmental conditions, and ultimately lead to the development of climatesmart crops. Understanding the sensing and signalling mechanisms that plants use to perceive and respond appropriately to stress is crucial for the development of stress-resistant crops using current strategies and technologies.