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The present study was focused on synthesis and characterization of copper nanoparticles to evaluate their efficacy against fruit rot pathogen of chilli crop. The green synthesis of nanoparticles was carried out by using extracts of Eucalyptus and Mint leaves. The synthesis of copper nanoparticles was confirmed by XRD, PSA, SEM and TEM. The average size of these particles synthesized by Eucalyptus leaf extract (CuNP-E) ranged from 10 to 130 nm, while as size of Mint leaf extract synthesized particles (CuNP-M) ranged from 23 to 39 nm, thus confirming their nano size. These green synthesized copper nanoparticles were evaluated against Colletotrichum capsici where Carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm served as standard checks. The mycelia inhibition of Colletotrichum capsici caused by copper nanoparticles was studied on PDA medium. CuNP-M @ 1000 ppm showed highest mycelial inhibition of 99.78% followed by 93.75% at 500 ppm and CuNP-E @ 1000 ppm compared to standard fungicides, carbendazim 50 WP @ 500 ppm (72.82%), and copper oxychloride 50 WP @ 2500 ppm (85.85%). The CuNP-M @ 500 ppm were significantly superior to carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm, but was statistically at par with CuNP-E @ 1000 ppm. This shows effectiveness of much lower concentration of copper nanoparticles compared to conventional fungicides. In detached fruit method, nanoparticles applied before inoculation of pathogen showed better results with regard to incubation period, lesion number and lesion size than after inoculation of pathogen. The present study reveals a simple, convenient, non-toxic and cost-efficient technique for the synthesis of nanoparticles and their effectiveness against Colletotrichum capsici. CuNP-M first time synthesized and evaluated against Colletotrichum capsici performed better than CuNP-E.

Spodoptera litura Fab. is a polyphagous pest causing damage to many agriculture crops leading to yield loss. Recurrent usage of synthetic pesticides to control this pest has resulted in resistance development. Plant-derived diterpenoid compound andrographolide was isolated from the leaves of Andrographis paniculata. It was analysed by gas chromatography-mass spectroscopy and quantified by HPLC. Nutritional indices and digestive enzymatic profile were evaluated. Third, fourth and fifth instar larvae were treated with different concentrations of andrographolide. At 3, 6 and 9 ppm-treated concentrations the larvae showed decreased RGR, RCR, ECI, ECD values with adverse increase in AD. The digestive enzymes were significantly inhibited when compared with control. Conspicuously, andrographolide showed pronounced mortality of S. litura by inhibition of enzyme secretion and intake of food. The binding ability of andrographolide with CYTP450 showed high affinity with low binding energy. Andrographolide has the potential to be exploited as a biocontrol agent against S. litura as an eco-friendly pesticide.

Levels of arsenic (As), chromium (Cr), and copper (Cu) are increasing in the soils worldwide. Such contaminants cause toxicity in the plant systems which adversely affects growth and productivity. The objective of the present investigation was to elucidate individual and combined effects of As, Cr, and Cu (100 μM each) stress in metal hyper-accumulator plant Indian mustard (Brassica juncea L.), exposed for a week. The highest accumulation was in the roots and in decreasing order viz. Cu > As > Cr. The magnitude of oxidative stress was maximal in combined stress, followed by As, Cr, and then Cu stress. Glutathione in conjunction with glutathione reductase, glutathione peroxidase, and glutathione S-transferase increased in all set of stress treatments, notably when exposed to Cr alone. In addition, the level of sulfur-rich compounds like cysteine, phytochelatins, and non-protein thiols increased under each stress indicating efficient coupling of the enzyme system and sulfur-containing compounds during stress conditions. The highest tolerance or growth index of plants was recorded for Cu. Protein profiling of leaf tissues showed modulation of protein patterns in each stress. Mediator of RNA polymerase II transcription subunit 1 isoform X1, RuBisCO (large subunit), and ribosomal protein S3 proteins were more abundant under Cr and Cu stress. Zinc finger A20/AN1 domain-containing stress-associated protein 5–like protein was more abundant under Cu stress. HSP (15.7 kDa) and autophagy protein 5–like were in higher abundance under As and combined stress. Our results suggest that Indian mustard has a differential mode of defense against a particular stressor at the level of protein expression profile.

Arsenic (As) is a toxic ubiquitous metalloid. Exposure of plants to As can result in various morphological, physiological and biochemical variations. Hydroponic experiment was conducted to study the growth response, lipid peroxidation, proline and antioxidant defence system under arsenic (As) stress in the cowpea. Ten day old seedlings of cowpea grown hydroponically, were treated with 0, 25, 50, 75 and 100 µM (Na2HAsO4) sodium arsenate for 7 days and analysed for morphological and biochemical traits under As stress. Significant decline in plant root and shoot length along with biomass was recorded with increased arsenic doses, as compared to control. The As treatment resulted in increased proline and decrease in malondialdehyde (MDA) content in seedlings of cowpea with increased concentration. Enzymatic antioxidants like catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) showed increased activity in dose dependant manner over control under As stress. Results indicated lower content of MDA and enhanced activities of the enzymatic antioxidant perform a significant role in As tolerance in cowpea.

The effects of climate temperature and water stress on growth and several stress markers were investigated in sweet basil plants. Some growth parameters (shoot length and number of leaves) and photosynthetic chlorophyll contents were determined every two days during plant growth, and foliage leaf material was collected after 15 and 21 days of treatment. Both climate temperature and water stress inhibited sweet basil plant growth; especially, total chlorophyll levels were decreased significantly in response to high-temperature treatments. Under strong stresses, basil plants induced the synthesis and accumulation of glycine betaine (GB) as a secondary osmolyte, although at less content when compared with the proline content under the same stress conditions. Proline concentrations particularly increased in leaves of both basil stressed plants, accomplishing levels high enough to play a crucial role in cellular osmoregulation adjustment. Stress-induced accumulation of these antioxidant compounds was detected in sweet basil. Therefore, it appears that sweet basil-treated plants are able to synthesize antioxidant compounds under strong stress conditions. On the other hand, total sugar concentrations decreased in stress-treated basil plants. Both temperature and water stress treatments caused oxidative stress in the treated plants, as indicated by a significant increment in malondialdehyde (MDA) concentrations. An increase in total phenolic and flavonoid concentrations in response to water stress and a highly significant decrease in carotenoid concentrations in basil leaves were observed; flavonoids also increased under high climate temperature conditions.

Nano-titanium dioxide (nTiO2) has been reported to improve tolerance of plants against different environmental stresses by modulating various physiological and biochemical processes. Nitric oxide (NO) has been shown to act as an important stress signaling molecule during plant responses to abiotic stresses. The present work was planned to investigate the involvement of endogenous NO in nTiO2-induced activation of defense system of fava bean (Vicia faba L.) plants under water-deficit stress (WDS) conditions. Water-suffered plants showed increased concentration of hydrogen peroxide (H2O2) and superoxide (O2 −) content coupled with increased electrolyte leakage and lipid peroxidation which adversely affected nitrate reductase (NR) activity, chlorophyll content and growth of the plants. However, application of 15 mg L−1 nTiO2 to stressed plants significantly induced NR activity and synthesis of NO which elevated enzymatic and non-enzymatic defense system of the stressed plants and suppressed the generation of H2O2 and O2 − content, leakage of electrolytes, and lipid peroxidation. Application of nTiO2, in association with NO, also enhanced the accumulation of osmolytes (proline and glycine betaine) that assisted the stressed plants in osmotic adjustment as witnessed by improved hydration level of the plants. Involvement of NO in nTiO2-induced activation of defense system was confirmed with NO scavenger cPTIO [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide] which caused recurrence of WDS.

The present study was conducted to evaluate the differences in photosynthetic parameters and antioxidant enzyme activity among two genotypes of soybean (Glycine max L.) in response to salinity stress. Ten-day-old seedlings, grown hydroponically, were treated with 0, 25, 50, 75, 100, 125 and 150 mM NaCl for 7 days and analysed for the traits as biomarkers for identification of salt-tolerant soybean genotype. It was observed that NaCl stress caused severe impairments in photosynthetic rate, chlorophyll fluorescence and chlorophyll content in both the genotypes, but the damage were much more pronounced in salt-sensitive genotype VL SOYA-47. Moreover, chlorophyll fluorescence measurements showed higher non-photochemical quenching in genotype VL SOYA-47 and lower in genotype VL SOYA-21. The antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) was observed much higher in VL SOYA-21 than in VL SOYA-47 at various levels of NaCl treatments. From the results, it could be suggested that VL SOYA-21 is the salt tolerant and VL SOYA-47 is a salt sensitive soybean genotype. The tolerance capacity of VL SOYA-21 against NaCl stress can be related with the ability of this genotype in possessing vital photosynthetic system and ROS scavenging capacity.

Soybean, the worldwide main source of oil and high protein feeds for the livestock sector has a high cadmium (Cd) accumulation capacity. With this background, the hydroponic culture experiments were conducted to investigate the effects of different concentrations of Cd (0-100 µM) on growth, water relations, photosynthetic variables, oxidative stress, and antioxidant response in two soybean genotypes P-218 and P-898. Ten days old seedlings were subjected to (0-100 µM CdCl2) for 15 days. The results indicated that the growth of genotype P-218 was not affected significantly upto 75 µM CdCl2 treatment growth of P-828 was reduced significantly beyond 25 µM CdCl2 treatments. Cd toxicity caused severe impairments in photosynthetic variables like photosynthetic rate, chlorophyll fluorescence and chlorophyll content, in P-898 than in P-218. The activities of antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) were higher in P-218 than in P-828 at various levels of Cd treatments. Chlorophyll fluorescence measurements revealed that non-photochemical quenching increased in P-218 and decreased in P-828 whereas the electron transport rate increased under Cd stress in P-828 and decreased in P-218. It is concluded that tolerance capacity of P-218 against Cd can be associated with the capability of this genotype in keeping an active photosynthetic system and strong antioxidant defense system.

The present investigation was conducted to evaluate salt tolerance in ten genotypes of soybean (Glycine max L.). Twelve-day-old seedlings, grown hydroponically, were treated with 0, 25, 50, 75, 100, 125 and 150 mM NaCl for 10 days. Growth, lipid peroxidation and antioxidant enzyme activities were evaluated. Growth, measured in terms of length, fresh weight and dry weight of plants, was drastically reduced in Pusa-24 while there was little effect of NaCl treatment on Pusa-37 genotype of soybean. High level of lipid peroxidation was observed in Pusa-24 as indicated by increased level of malondialdehyde. Activities of superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were maximum in Pusa-37 where 9-, 1-, 5- and 6-fold increase over control were observed, respectively. The results suggested that Pusa-24 and Pusa-37 are salt-sensitive and salt-tolerant genotype of soybean, respectively, and antioxidant defence system is involved in conferring the sensitiveness and tolerance in these genotypes. Salt-tolerant genotype Pusa-37, was further analysed by 2-dimensional gel electrophoresis to analyse the differential expression of proteins at high salt stress. In the present study, 173 protein spots were identified. Of these, 40 proteins were responsive to salinity in that they were either up- or downregulated. This study could help us in identifying the possible regulatory switches (gene/s) controlling novel proteins of the salt-tolerant genotype of the crop plants and their possible role in defence mechanism.

Ten genotypes of wheat (Triticum aestivum L.) were grown for 20 days in complete nutrient solution with 1 mM (nitrogen-insufficient), 4 mM (nitrogen-moderate) and 10 mM (nitrogen-sufficient) nitrogen (N) levels, and nitrogen efficiency (NE) was analyzed. Of these 10 genotypes, VL829 was identified as the most N-efficient, while HUW234 the most N-inefficient. To find out the physiological basis of this difference, we investigated the possible role of influx across the root cell plasma membrane in conferring NE by measuring the short-term uptake in selected 10 genotypes. 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 VL829 is mediated by both high- and low-affinity nitrate transporter systems, while that of HUW234 by only low affinity nitrate transporter system. The study suggests that root uptake rate may play an important role in conferring N- efficiency of whea...

The present investigation was conducted to evaluate salt tolerance in nine genotypes of soybean (Glycine max L.). Ten-day-old seedlings, grown hydroponically, were treated with 0, 25, 50, 75, 100, 125 and 150 mM NaCl for five days. Growth, lipid peroxidation and antioxidant enzyme activities were evaluated. Growth, measured in terms of length, fresh weight and dry weight of plants, was drastically reduced in PK-416, while there was little effect of NaCl treatment on Pusa-37 genotype of soybean. A high level of lipid peroxidation was observed in PK-416 as indicated by increased level of malondialdehyde. Activities of superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were maximum in Pusa-37 where 9-fold, 1-fold, 5-fold and 6-fold increases over control were observed, respectively. The results suggested that PK-416 and Pusa-37 are salt-sensitive and salt-tolerant genotypes of soybean, respectively, and antioxidant defence systems involved in conferring the sensitiveness ...

The exploitation of DNA polymorphisms by an ever-increasing number of molecular marker technologies has begun to have an impact on animal and plant genome research and breeding. A large number of different molecular techniques for genetic diversity analysis are available and each of them differs in its informational content. These techniques not only helped in understanding the different structure and behavior of species genome, but also revolutionized and modernized the ability to characterize genetic variation. Identification of marker linked to useful traits has been based on complete linkage maps and bulked segregation analysis. Markers are therefore used to identify traits, their inheritance and characterize germplasm.

The growing area of genetically modified (GM) crops has significantly expanded since they were first commercialized in 1996. Currently 400 million acres of the fertile land worldwide are used to cultivate genetic engineering (GE) crops such as rice, corn, cotton, and soybeans. Genetically modified crops are increasingly gaining acceptance and their adoption has brought huge economic and environmental benefits. In the past 17 years, these achievements have been primarily supported by two simple traits of herbicide tolerant and insect resistant crops. Concurrently GM crops generated intense consumer debate in many parts of the world. The issues under debate include the costs and benefits of the GM crops and the inherent safety concerns. It is widely claimed, however, that biotechnology, particularly genetically engineered food offers dramatic promise for meeting some of the twenty-first century’s greatest challenges; as do all new technologies, it also poses certain apprehensions and risks, both known and unknown. The introduction of Bacillus thuringiensis (Bt) genes into the plants has raised issues related to its risk assessment and biosafety. The chapter presents an overview of the production of GM crops, their adequacy, detection strategies, biosafety issues, and potential impact on society. Furthermore, the future prospects of the GM crops are also highlighted.

Among abiotic factors, salinity and drought stress affect every aspect of plant from physiology to metabolic activities. Understanding of abiotic stress responses and signal transduction to control adaptive pathways is a crucial step in determining the plant resistance exposed to unfavorable environments. Molecular and genomic findings have shown several changes in gene expression profiling under drought and salt stresses in plants. Numbers of transcription factors which are accountable for inducing stress-responsive genes have been documented. To survive in adverse condition, plants have stress‐specific and adaptive responses which provide them necessary protection. Although, there are several signaling pathways and stress-responsive perceptions, some of which are definite in function, while others may have cross talk. Expressions of a large number of transcripts and genes are induced by these abiotic stresses in plants which facilitate stress tolerance and stress response. Recently, progress has been made in investigating the complex cascades of gene expression in stress responses. Knowledge about plant stress signaling is essential for the development of transgenic and improving breeding strategies in crops under stress environment. This chapter provides an outline of the common features of stress signaling in plants with some current studies on the functional analysis of signaling machineries under salt and drought stresses.

Nitrogen (N) is an essentially critical element which is involved in signalling and can affect plant growth and development. The plants have evolved different strategies involving short- and long-ranged signalling pathways to cope with the changes in N regulations in the soil. These pathways work at cell and plant level for coordination of N metabolism, growth, and development in accordance with the external and the internal N status. Currently, identification and characterization of local and systemic signalling has been emphasized, but information about integrating coordination and organization of N response of the plants is still lacking. Tracing out the full N pathway could help us to devise and produce high N-efficient genotypes and increase Nitrogen use efficiency (NUE). In this chapter, we discuss the physiological as well as molecular means to understand the mechanisms involved in local and systemic nitrogen responses and how these responses are coordinated.

26 páginas, 6 figuras, 7 tablas., [Background]: The combination of high-throughput transcript profiling and next-generation sequencing technologies is a prerequisite for genome-wide comprehensive transcriptome analysis. Our recent innovation of deepSuperSAGE is based on an advanced SuperSAGE protocol and its combination with massively parallel pyrosequencing on Roche’s 454 sequencing platform. As a demonstration of the power of this combination, we have chosen the salt stress transcriptomes of roots and nodules of the third most important legume crop chickpea (Cicer arietinum L.). While our report is more technology-oriented, it nevertheless addresses a major world-wide problem for crops generally: high salinity. Together with low temperatures and water stress, high salinity is responsible for crop losses of millions of tons of various legume (and other) crops. Continuously deteriorating environmental conditions will combine with salinity stress to further compromise crop yields. As a good example for such stress-exposed crop plants, we started to characterize salt stress responses of chickpeas on the transcriptome level. [Results]: We used deepSuperSAGE to detect early global transcriptome changes in salt-stressed chickpea. The salt stress responses of 86,919 transcripts representing 17,918 unique 26 bp deepSuperSAGE tags (UniTags) from roots of the salt-tolerant variety INRAT-93 two hours after treatment with 25 mM NaCl were characterized. Additionally, the expression of 57,281 transcripts representing 13,115 UniTags was monitored in nodules of the same plants. From a total of 144,200 analyzed 26 bp tags in roots and nodules together, 21,401 unique transcripts were identified. Of these, only 363 and 106 specific transcripts, respectively, were commonly up- or down-regulated (>3.0-fold) under salt stress in both organs, witnessing a differential organ-specific response to stress. Profiting from recent pioneer works on massive cDNA sequencing in chickpea, more than 9,400 UniTags were able to be linked to UniProt entries. Additionally, gene ontology (GO) categories over-representation analysis enabled to filter out enriched biological processes among the differentially expressed UniTags. Subsequently, the gathered information was further cross-checked with stress-related pathways. From several filtered pathways, here we focus exemplarily on transcripts associated with the generation and scavenging of reactive oxygen species (ROS), as well as on transcripts involved in Na+ homeostasis. Although both processes are already very well characterized in other plants, the information generated in the present work is of high value. Information on expression profiles and sequence similarity for several hundreds of transcripts of potential interest is now available. [Conclusions]: This report demonstrates, that the combination of the high-throughput transcriptome profiling technology SuperSAGE with one of the next-generation sequencing platforms allows deep insights into the first molecular reactions of a plant exposed to salinity. Cross validation with recent reports enriched the information about the salt stress dynamics of more than 9,000 chickpea ESTs, and enlarged their pool of alternative transcripts isoforms. As an example for the high resolution of the employed technology that we coin deepSuperSAGE, we demonstrate that ROS-scavenging and -generating pathways undergo strong global transcriptome changes in chickpea roots and nodules already 2 hours after onset of moderate salt stress (25 mM NaCl). Additionally, a set of more than 15 candidate transcripts are proposed to be potential components of the salt overly sensitive (SOS) pathway in chickpea. Newly identified transcript isoforms are potential targets for breeding novel cultivars with high salinity tolerance. We demonstrate that these targets can be integrated into breeding schemes by micro-arrays and RT-PCR assays downstream of the generation of 26 bp tags by SuperSAGE, Work of the authors was supported by a grant from the Aquarhiz project (INCOCT- 2004-509115) to GK, grants from the Grain Legumes project (Food-CT- 2004-506223) to GK and GenXPro GmbH, and from DFG to GK (Ka 332/22-1).