Drought-Mediated Modulation in Metabolomic Profiling of Nigella Sativa Leaf, Growth, Ecophysiology and Antioxidants

Abiotic stresses,including drought,have been found to affect the growth and medicinal quality of numerous herbs.The proposed study aims to study the effects of different drought regimes on the metabolic profile,growth,ecophysiology,cellular antioxidants,and antioxidant potential of Nigella sativa(Black cumin)leaf.Forty-day-old seedlings of N.sativa were exposed to three regimes of drought(control,moderate and high)for a week.UPLCMS/MS metabolic profile of the leaf reveals the presence of more than a hundred metabolites belonging to anthocyanins,chalcones,dihydro flavonoids,flavonoids,flavanols,flavones,flavonoid carbonoside,isoflavones,etc.Drought was found to alter the contents of identified metabolites.Drought stress-induced oxidative stress and increased production of hydrogen peroxide and superoxide anions.Physiological changes,activities of antioxidant enzymes,contents of antioxidants,and proline were significantly high under drought to protect against the low water regimes.Furthermore,stressed leaf extract had higher antioxidant potential.Thus,N.sativa leaf bears multiple metabolic pathways and can tolerate a higher degree of drought or osmotic stress.

Exogenous Selenium Mitigates Salt Stress in Soybean by Improving Growth,Physiology,Glutathione Homeostasis and Antioxidant Defense

The mechanism of selenium(Se)-induced salt tolerance was studied in moderately sensitive soybean(Glycine max L.)plants.To execute this view,soybean plants were imposed with salt stress(EC 6 dS m^(−1))applying NaCl.In other treatments,Se(0,25,50 and 75μM Na_(2)SeO_(4))was sprayed as co-application with that level of salt stress.Plant height,stem diameter,leaf area,SPAD value decreased noticeably under salt stress.Altered proline(Pro)level,together with decreased leaf relative water content(RWC)was observed in salt-affected plants.Salt stress resulted in brutal oxidative damage and increased the content of H_(2)O_(2),MDA level and electrolyte leakage.Exogenous Se spray alleviated oxidative damage through boosting up the antioxidant defense system by increasing the activity of antioxidant enzymes such as catalase(CAT),peroxidase(POD)and glutathione reductase(GR),as well as by improving non-enzymatic antioxidants like glutathione(GSH)and GSH/glutathione disulfide(GSSG).The upregulated antioxidant defense system,restored Pro and leaf RWC,higher SPAD value conferred better growth and development in Se-sprayed salt-affected soybean plants which altogether put forth for the progressive yield contributing parameters and finally,seed yield.Among different doses of Se,soybean plants sprayed with 50μM Na_(2)SeO_(4)showed better salt tolerance.

Physiological and Molecular Analysis of Applied Nitrogen in Rice Genotypes

Ten genotypes of rice （Oryza sativa L.） were grown for 30 d in complete nutrient solution with 1 mmol/L （N-insufficient）,4 mmol/L （N-moderate） and 10 mmol/L （N-high） nitrogen levels,and nitrogen efficiency （NE） was analyzed.Growth performance,measured in terms of fresh weight,dry weight and lengths of root and shoot,was higher in N-efficient than in N-inefficient rice genotypes at low N level.Of these 10 genotypes,Suraksha was identified as the most N-efficient,while Vivek Dhan the most N-inefficient.To find out the physiological basis of this difference,the nitrate uptake rate of root and the activities of nitrate assimilatory enzymes in leaves of N-efficient and N-inefficient rice genotypes were studied.Uptake experiments revealed the presence of two separate nitrate transporter systems mediating high-and low-affinity nitrate uptake.Interestingly,the nitrate uptake by the roots of Suraksha is mediated by both high-and low-affinity nitrate transporter systems,while that of Vivek Dhan by only low-affinity nitrate transporter system.Study of the activities and expression levels of nitrate assimilatory enzymes in N-efficient and N-inefficient rice genotypes showed that nitrate reductase （NR） and glutamine synthetase （GS） play important roles in N assimilation under low-nitrogen conditions.

Morpho-Physiological,Biochemical and Molecular Adaptation of Millets to Abiotic Stresses:A Review

Abiotic stresses such as drought,heat,cold,nutrient deficiency,excess salt and hazardous metals can hamper plantgrowth and development.Intensive agriculture of only a few major staple food crops that are sensitive and intolerant to environmental stresses has led to an agrarian crisis.On the other hand,nutritionally rich,gluten free and stress tolerant plants like millets are neglected and underutilized.Millets sustain about one-third of the world’s population and show exceptional tolerance to various abiotic and biotic stresses.Millets are C4 plants that are adapted to marginal and dry lands of arid and semi-arid regions,and survive low rainfall and poor soils.Abiotic stresses significantly affect plant growth which ultimately results in reduced crop yields.However,various adaptation mechanisms have evolved in millets to withstand different stresses.This review aims at exploring various of these morphophysiological,biochemical and molecular aspects of mechanisms in millets.Morphological adaptations include short life span,smallplant height and leaf area,dense root system,adjusted flowering time,increased root and decreased shoot lengths,high tillering,and leaf folding.A high accumulation of various osmoprotectants(proline,soluble sugars,proteins)improves hyperosmolarity and enhances the activity of antioxidant enzymes(e.g.,Ascorbate peroxidase,Superoxide dismutase,Catalase,Peroxidase)providing defense against oxidative damage.Physiologically,plants show low photosynthetic and stomatal conductance rates,and root respiration which help them to escape from water stress.Molecular adaptations include the upregulation of stress-related transcriptional factors,signalling genes,ion transporters,secondary metabolite pathways,receptor kinases,phytohormone biosynthesis and antioxidative enzymes.Lack of genetic resources hampers improvement of millets.However,several identified and characterized genes for stress tolerance can be exploited for further development of millet resilience.This will provide them with an extra characteristic plant resistance to withstand environmental pressures,besides their excellent nutritional value over the conventional staple crops like rice,wheat and maize.

Pomegranate peel extract lessens histopathologic changes and restores antioxidant homeostasis in the hippocampus of rats with aluminium chloride-induced Alzheimer’s disease

Objective:To investigate the neuroprotective efficacy of pomegranate and ellagic acid on the histopathological changes in the hippocampus of an aluminium chloride(AlCl<sub>3)induced rat model of Alzheimer’s disease.Methods:Sprague Dawley rats were divided into 4 groups(n=10each):GroupⅠ:serving as negative control;GroupⅡ,Alzheimer model,induced by administration of 17 mg/kg bw AlCl3;GroupⅢ,administered the same dose of AlCl3 with 50 mg/kg of pomegranate peel extract and GroupⅣ:administered ellagic acid(50 mg/kg)in addition to the same dose of AlCl3.The medication given to all groups continued for 28 days.All were given the compounds by gastric gavage.Radial arm maze test,hippocampus antioxidant markers,histopathology of the dentate gyrus,and CA3 of the hippocampus were evaluated.Results:Rats treated with pomegranate peel extract exposed to radial arm maze test showed less number of errors and reduced time needed to reach the criterion.There was an increase in the levels of glutathione,catalase,and total antioxidant capacity and decreased lipid peroxidation products.Histopathological features in dentate gyrus and CA3 as apoptosis and chromatolysis of pyramidal cells and granular layer,respectively,were decreased.Alzheimer characteristic neurofibrillary tangles and senile plaques were reduced.Treatment with ellagic acid ameliorated the pathological results but to a statistically lower level.Conclusions:Pomegranate peel extract alleviates memory deficit and restores antioxidant homeostasis following degenerative changes in the hippocampus induced by aluminium chloride in rats.

Changes in Growth,Photosynthetic Pigments,Cell Viability,Lipid Peroxidation and Antioxidant Defense System in Two Varieties of Chickpea(Cicer arietinum L.)Subjected to Salinity Stress

Salinity is one of the most severe abiotic stresses for crop production.The present study investigates the salinityinduced modulation in growth indicators,morphology and movement of stomata,photosynthetic pigments,activity of carbonic anhydrase as well as nitrate reductase,and antioxidant systems in two varieties of chickpea(Pusa-BG5023,and Pusa-BGD72).On 20^(th) day of sowing,plants were treated with varying levels of NaCl(0,50,100,150 and 200 mM)followed by sampling on 45 days of sowing.Recorded observations on both the varieties reveal that salt stress leads to a significant decline in growth,dry biomass,leaf area,photosynthetic pigments,protein content,stomatal behavior,cell viability,activity of nitrate reductase and carbonic anhydrase with the rise in the concentration of salt.However,quantitatively these changes were less in Pusa-BG5023 as compared to Pusa-BGD72.Furthermore,salinity-induced oxidative stress enhanced malondialdehyde content,superoxide radicals,foliar proline content,and the enzymatic activities of superoxide dismutase,catalase,and peroxidase.The variety Pusa-BGD72 was found more sensitive than Pusa-BG5023 to salt stress.Out of different graded concentrations(50,100,150 and 200 mM)of sodium chloride,50 mM was least toxic,and 200 mM was most damaging.The differential behavior of these two varieties measured in terms of stomatal behavior,cell viability,photosynthetic pigments,and antioxidant defense system can be used as prospective indicators for selection of chickpea plants for salt tolerance and sensitivity.

Salt Stress Threshold in Millets:Perspective on Cultivation on Marginal Lands for Biomass

Millets hold an immense assurance for food safety and nourishment amid ever-rising agricultural expenses and climate alterations.They are healthful,have supplementary wellbeing profit and need remarkably fewer effort overheads for crop growing.These characters draw attention to millets as a plant of preference for the humankind in the course of emergent alarm about environmental changes.Millets have the prospect to provide biomass and thus bioenergy,reduced carbon emission,carbon footprint and sustainable modern agriculture.As the rate of expansion in budding countries is increasing day by day,the scarcity of energy is a big panic and there is a mounting turn in the direction and rehearsal of waste and biomass as an energy source.Globally,at least 20%of total irrigated land has been injured by salt and 1.5 million hectares is taken away of cultivation every year.Thus,in future,we will have a requirement of efficient crops and utilisation of marginal lands for agriculture.Millet is an answer to the efficient crop.Plants are subjected to various environmental pressures(high/low temperature,heavy metal,salinity,pesticides,etc.)as well as biotic stresses(virus,bacteria,fungi,etc.)and millets are not an exception to it.Millets are categorised as glycophytes and can tolerate average salt threshold of about 6(ECe)(dS/m)with some variation from specie to specie.Increase in the salt concentrations can lead to retarded growth and development,thus need for mitigants arise to reduce such stresses.Some mitigants to overcome the stress levels include proline,polyamine and betaines,Na2SeO3,H2S,KNO3,Mg(NO3)2,etc.

Recent Developments to Mitigate Selenium Deficiency in Agricultural Eco-Systems

Under changing climate,trace elements like selenium(Se)have emerged as vital constituent of agro-ecosystems enabling crop plants to off-set the adverse effects of suboptimal growth conditions.The available form of selenium is important for boosting its bioavailability to crop plants having varied agro-botanical traits and root architectural systems.As compared to selenite,the selenate has a weaker soil bonding,higher absorption in the soil solution which results in a comparatively absorption by plant roots.Various factors including dry climate,high pH,optimal ambient air temperature,less accumulation of water,and low concentration of organic matter in the soil tend to boost the selenate ratio in the soil.The use of selenium pelleted seeds has emerged as an interesting and viable alternative to alleviate selenium deficiency in agricultural eco-systems.Similarly,the co-inoculation of a mixture of Selenobacteria and Arbuscular mycorrhizal fungi represents an evolving promising strategy for the bio-fortification of wheat plants to produce selenium-rich flour to supplement human dietary needs.Furthermore,in-depth research is required to assure the effectiveness of biological fertilization procedures in field conditions as well as to explore and increase our understanding pertaining to the underlying main mechanisms and channels of selenium absorption in plants.The focus of this review is to synthesize the recent developments on Se dynamics in soil-plant systems and emerging promising strategies to optimize its levels for crop plants.Recent developments regarding the use of micro-organisms as a biotechnological mean to enhance plant nutrition and crop quality have been objectively elaborated.The study becomes even more pertinent for arid and semi-arid agro-ecosystems owing to the potential role of selenium in providing stress tolerance to crop plants.Moreover,this review synthesizes and summarizes the recent developments on climate change and bioavailability,and the protective role of selenium in crop plants.

The Primacy of Moringa(Moringa oleifera Lam.)in Boosting Nutrition Status and Immunity Defence Amidst the COVID-19 Catastrophe:A Perspective

A severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)led novel coronavirus disease(COVID-19)outbreak spread through China has become the biggest global public health challenge today.The virus upon several mutations has led to the resurgence of more infectious and lethal variants infecting over 298 million people with more than 5.46 million deaths worldwide by the end of December,2021.Though vaccines are available,various preventive measures particularly a high body immunity is still extremely important which determines the likelihood of disease severity and subsequent recovery in the current and future pandemics.This review acknowledges the potentiality of miraculous Moringa oleifera Lam.against recently evolved novel coronavirus and accompanying health complications.Moringa a well-proven super-food,densely packed with an abundant quantity of 92 minerals,several vitamins,46 antioxidants,and numerous bioactive compounds,thus own a massive therapeutic potential for healing all levels of nutritional deficiencies and poor immunities and cure above 300 diseases.Moringa acts as anti-asthmatic,anti-cancerous,anti-diabetic,anti-inflammatory,hypotensive,hepatic,renal and cardio-protective,and anti-viral in nature.Thus it may reduce the severity of COVID-19 infections and associated serious medical emergencies.In addition,self-isolation at home or the workplace has put people at increased risk of physical and mental sicknesses,which could be simply addressed by integrating this wonderful plant into everyday diet.Furthermore,the immune-modulatory properties and viral inhibiting nature of moringa contribute to reduced risk of COVID-19 infection and quicker recovery from its symptoms.As per the existing pieces of literature,it is a great time to harness the esteemed moringa for safeguarding people from the terrible ongoing COVID-19 situation and other future pandemics.

Nanotechnology-Based Advancements in Postharvest Management of Horticultural Crops

Horticulture is a branch of Agricultural science where it is defined as the science and art of cultivating and handling fruits,vegetables,ornamental plants and several plants having unique medicinal and aromatic values.Horticultural crops provide farmers with high income and have good export quality,but they have a concern about postharvest losses.Hence,increasing productivity and decreasing post-harvest losses by using scientific studies and techniques like biotechnology and nanotechnology could be the simplest possible solution to the above-mentioned problems.Using nanotechnology which is having the characteristics of nanoparticles is proven to be very useful in science and technological applications.Nanotechnology-based formulations increase the product quality and the shelf life of horticultural products and provide multiple ways of inhibiting the growth and development of microorganisms.It is precisely a new edible packaging coverage(film)that controls the exchange of gases and prevents damage from harmful rays such as ultraviolet radiation to a greater extent.Increasing strength by using nano biosensors for labeling products is considered a fundamental process to automated control of storage products.Postharvest rotting of vegetables is recognized to be an oxidative reaction and microbial deterioration as well.This review will address all such nanotechnology-based advancements for minimizing post-harvest losses of horticultural crops and enhancing the socio-economical progress of growers in particular.

Effect of Cadmium Stress on the Growth,Physiology,Stress Markers,Antioxidants and Stomatal Behaviour of Two Genotypes of Chickpea(Cicer arietinum L.)

The current work was performed to know the impact of cadmium(Cd)toxicity on two different genotypes of chickpea(Cicer arietinum L.)namely Pusa-BG1053 and Pusa-BG372.Cadmium was applied in the form of cadmium chloride(CdCl_(2)),in varying levels,0,25,50,75,and 100 mg Cd kg^(-1)soil.Plant growth as well as physiological attributes were decreased with increasing concentration of Cd.Both genotypes showed the maximum and significant reduction at the maximum dose of Cd(100 mg Cd kg^(-1)soil).Results of this study proved that the genotype Pusa-BG1053 was more tolerant and showed a lower decline in growth,photosynthetic and biochemical attributes than Pusa-BG372.This later genotype showed the maximum reduction and was sensitive to Cd stress.A better activity of antioxidants protected Pusa-BG1053 from Cd toxicity;on the other hand,the activity of antioxidants was much lower in Pusa-BG372.Scanning electron microscopic studies showed differences in both genotypes.In Pusa-BG1053,stomatal quantity was higher and stomata were slightly close to the characteristic guard cells.In Pusa-BG372 stomata were lower,slightly open and with highly affected guard cells.Root cell mortality due to the harsh effects of Cd appeared to be more evident in Pusa-BG372 than Pusa-BG1053,which was visible under a confocal microscope.As a result of this study,Pusa-BG1053 was a more tolerant genotype,and exhibited a minimum reduction in terms of all studied parameters than Pusa-BG372,which was a sensitive genotype to Cd toxicity.

Phenotypic and Molecular Assessment of Wheat Genotypes Tolerant to Leaf Blight,Rust and Blast Diseases

Globally among biotic stresses,diseases like blight,rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh.For sustainable productivity,the development of disease-resistant lines and high yielding varieties is vital and necessary.This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute with aims to identify genotypes having high yield potential and resistant to leaf blight,leaf rust and blast diseases.These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition.Out of 122 genotypes tested,20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve under both irrigated timely sown and irrigated late sown conditions.Forty-two genotypes were found completely free from leaf rust infection,59 genotypes were identified as resistant,and 13 genotypes were identified as moderately resistant to leaf rust.Eighteen genotypes were immune against wheat blast,42 genotypes were categorized as resistant,and 26 genotypes were identified as moderately resistant to wheat blast.Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions.The genotypes BAW 1322,BAW 1295,and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372,BAW 1373,BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height.The genotypes WMRI Gom 1,BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1,BAW 1297,BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition.The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.

Assessment of the Contribution of Foliar Trichomes towards Allelopathy

Plant trichomes vary in their structure and cellular composition.Glandular trichomes contain a bulk of specific(secondary)metabolites of diverse nature.Trichomes are connected with various adaptive processes,which include protection against herbivores and pathogens as well.Our study investigates the allelopathic contribution of structures present on the leaf surface of Nicotiana plumbaginifolia Viv.against seedling growth of Cicer arietinum L.The infusion obtained after dipping Nicotiana leaves in Dichloromethane(DCM)for 10 seconds(s)was the most phytotoxic among all the infusions.The observed inhibition in Cicer growth was not only dependent on type of infusion but also the concentration.Scanning electron microscopy of the leaf samples showed the modifications in trichomes under the influence of the different concentration of DCM.Glandular trichomes were most dehydrated at 10 seconds in DCM,suggesting their role for the observed allelopathy.Such study on the biochemistry of trichomes and their phytotoxicity may develop highly valuable objects for plant metabolic engineering.

Application of GIS for the identification and demarcation of selective heavy metal concentrations in the urban groundwater

Groundwater is the most appropriate and widely used source of drinking water, which is increasingly threatened by pollution from industrial and agricultural activities. To check the severity of the problem, 156 groundwater samples were collected from various depths （60-110 ft） of 52 different localities in Faisalabad city, the third largest metropolis in Pakistan, and analyzed for the metals （Zn, Cu, Cd, Ni, Pb, Mn and Fe） concentration in 2009. Quantification was done by using Flame Atomic Absorption Spectrophotometer technique and the results were compared with WHO standards for drinking water quality. Results showed that the levels of Cu, Mn and Fe were below the WHO standards while the concentrations of Zn, Cd, Ni and Pb were above the recommended levels of safe drinking water. Correlation analysis among the occurrence of these heavy metals revealed a highly significant and positive correlation of Mn with Zn and Fe. A significant and positive correlation of Cd was also found with Cu and groundwater depth showing that there is strong association between Cu-Cd pair and that the Cd concentration varies with depth of groundwater in the study area. Regional patterns of heavy metals occurrence were mapped using Geographical Information System （GIS） for the identification and demarcation of risk areas. The concentration maps may be used by policymakers of the city to mitigate groundwater pollution.