Molecular and genetic perspectives of cold tolerance in wheat.

Environmental variation is the most crucial problem as it is causing food insecurity and negatively impacts food availability, utilization, assessment, and stability. Wheat is the largest and extensively cultivated staple food crop for fulfilling global food requirements. Abiotic stresses including salinity, heavy metal toxicity, drought, extreme temperatures, and oxidative stresses being the primary cause of productivity loss are a serious threat to agronomy. Cold stress is a foremost ecological constraint that is extremely influencing plant development, and yield. It is extremely hampering the propagative development of plant life. The structure and function of plant cells depend on the cell's immune system. The stresses due to cold, affect fluid in the plasma membrane and change it into crystals or a solid gel phase. Plants being sessile in nature have evolved progressive systems that permit them to acclimatize the cold stress at the physiological as well as molecular levels. The phenomenon of acclimatisation of plants to cold stress has been investigated for the last 10 years. Studying cold tolerance is critical for extending the adaptability zones of perennial grasses. In the present review, we have elaborated the current improvement of cold tolerance in plants from molecular and physiological viewpoints, such as hormones, the role of the posttranscriptional gene, micro RNAs, ICE-CBF-COR signaling route in cold acclimatization and how they are stimulating the expression of underlying genes encoding osmoregulatory elements and strategies to improve cold tolerance in wheat.

Nanotechnologies for environmental remediation and their ecotoxicological impacts.

Environmental nanoremediation is an emerging technology that aims to rapidly and efficiently remove contaminants from the polluted sites using engineered nanomaterials (ENMs). Inorganic nanoparticles which are generally metallic, silica-based, carbon-based, or polymeric in nature serve to remediate through chemical reactions, filtration, or adsorption. Their greater surface area per unit mass and high reactivity enable them to treat groundwater, wastewater, oilfields, and toxic industrial contaminants. Despite the growing interest in nanotechnological solutions for bioremediation, the environmental and human hazard associated with their use is raising concerns globally. Nanoremediation techniques when compared to conventional remediation solutions show increased effectivity in terms of cost and time; however, the main challenge is the ability of ENMs to remove contaminants from different environmental mediums by safeguarding the ecosystem. ENMs improving the accretion of the pollutant and increasing their bioavailability should be rectified along with the vigilant management of their transfer to the upper levels of the food chain which subsequently causes biomagnification. The ecosystem-centered approach will help monitor the ecotoxicological impacts of nanoremediation considering the safety, sustainability, and proper disposal of ENMs. The environment and human health risk assessment of each novel engineered nanomaterial along with the regulation of life cycle assessment (LCA) tools of ENMs for nanoremediation can help investigate the possible environmental hazard. This review focuses on the currently available nanotechnological methods used for environmental remediation and their potential toxicological impacts on the ecosystem.

Osmoregulation and its actions during the drought stress in plants.

Drought stress, which causes a decline in quality and quantity of crop yields, has become more accentuated these days due to climatic change. Serious measures need to be taken to increase the tolerance of crop plants to acute drought conditions likely to occur due to global warming. Drought stress causes many physiological and biochemical changes in plants, rendering the maintenance of osmotic adjustment highly crucial. The degree of plant resistance to drought varies with plant species and cultivars, phenological stages of the plant, and the duration of plant exposure to the stress. Osmoregulation in plants under low water potential relies on synthesis and accumulation of osmoprotectants or osmolytes such as soluble proteins, sugars, and sugar alcohols, quaternary ammonium compounds, and amino acids, like proline. This review highlights the role of osmolytes in water-stressed plants and of enzymes entailed in their metabolism. It will be useful, especially for researchers working on the development of drought-resistant crops by using the metabolic-engineering techniques.

Nitrate and Nitrogen Oxides: Sources, Health Effects and Their Remediation.

Increased use of nitrogenous (N) fertilizers in agriculture has significantly altered the global N-cycle because they release nitrogenous gases of environmental concerns. The emission of nitrous oxide (N2O) contributes to the global greenhouse gas accumulation and the stratospheric ozone depletion. In addition, it causes nitrate leaching problem deteriorating ground water quality. The nitrate toxicity has been reported in a number of studies showing the health hazards like methemoglobinemia in infants and is a potent cause of cancer. Despite these evident negative environmental as well as health impacts, consumption of N fertilizer cannot be reduced in view of the food security for the teeming growing world population. Various agronomic and genetic modifications have been practiced to tackle this problem. Some agronomic techniques adopted include split application of N, use of slow-release fertilizers, nitrification inhibitors and encouraging the use of organic manure over chemical fertilizers. As a matter of fact, the use of chemical means to remediate nitrate from the environment is very difficult and costly. Particularly, removal of nitrate from water is difficult task because it is chemically non-reactive in dilute aqueous solutions. Hence, the use of biological means for nitrate remediation offers a promising strategy to minimize the ill effects of nitrates and nitrites. One of the important goals to reduce N-fertilizer application can be effectively achieved by choosing N-efficient genotypes. This will ensure the optimum uptake of applied N in a balanced manner and exploring the molecular mechanisms for their uptake as well as metabolism in assimilatory pathways. The objectives of this paper are to evaluate the interrelations which exist in the terrestrial ecosystems between the plant type and characteristics of nutrient uptake and analyze the global consumption and demand for fertilizer nitrogen in relation to cereal production, evaluate the various methods used to determine nitrogen use efficincy (NUE), determine NUE for the major cereals grown across large agroclimatic regions, determine the key factors that control NUE, and finally analyze various strategies available to improve the use efficiency of fertilizer nitrogen.

Molecular and ecological investigations on the wild populations of Glycyrrhiza L. taxa distributed in the East Mediterranean Area of Turkey.

This paper covers studies on the molecular and ecological aspects of G. glabra var. glandulifera, G. flavescens ssp. flavescens and G. echinata collected from Hatay (Turkey); with the aim to better understand their genetic variation and ecological requirements for possible conservation programs. The material including total genomic DNA was extracted by the CTAB, and for PCR reaction, a total of 14 SSR primers developed for Medicago truncatula were used. PCR amplifications were performed in a Multigen® Thermal Cycler. Soil samples were analysed for their texture, pH, total soluble salts, calcium carbonate, total N content, total phosphorus and organic matter content. In order to see the association between genetic, ecological and geographical data, a similarity matrix was generated. Genetic similarity distances between genotypes were correlated with those of Eucledian distances obtained from ecological and geographical data. Analysis of molecular variance (AMOVA) was performed using GenAlEx 6.5 software to determine variation among and within genetic variations. The genetic analysis showed that the highest expected heterozygosity values were obtained from G. glabra while the lowest were obtained from G. echinata. In general heterozygosity values were low, especially for G. echinata. Therefore, variation appears to be lower within each species than among three species. The physical and chemical analysis of soil and plant samples indicates that mineral accumulation in plants is substantially affected by the soil characteristics. There is a need for identification of better strategies for the improvement of varieties, especially for small farmers managing marginal soils. More studies should be conducted in order to safeguard these taxa, especially G. glabra var. glandulifera which is collected intensively due to its economic value, the same is true for endemic taxon G. flavescens ssp. flavescens.

ROS Homeostasis and Antioxidants in the Halophytic Plants and Seeds.

Reactive oxygen species (ROS) are excited or partially reduced forms of atmospheric oxygen, which are continuously produced during aerobic metabolism like many physiochemical processes operating throughout seed life. Previously, it was believed that ROS are merely cytotoxic molecules, however, now it has been established that they perform numerous beneficial functions in plants including many critical roles in seed physiology. ROS facilitate seed germination via cell wall loosening, endosperm weakening, signaling, and decreasing abscisic acid (ABA) levels. Most of the existing knowledge about ROS homeostasis and functions is based on the seeds of common plants or model ones. There is little information about the role of ROS in the germination process of halophyte seeds. There are several definitions for halophytic plants, however, we believed "halophytes are plants that can grow in very saline environment and complete their life cycle by adopting various phenological, morphological and physiological mechanisms at canopy, plant, organelle and molecular scales". Furthermore, mechanisms underlying ROS functions such as downstream targets, cross-talk with other molecules, and alternative routes are still obscure. The primary objective of this review is to decipher the mechanisms of ROS homeostasis in halophytes and dry seeds, as well as ROS flux in germinating seeds of halophytes.

Potential effect of luteolin, epiafzelechin, and albigenin on rats under cadmium-induced inflammatory insult: In silico and in vivo approach.

Introduction: Cadmium(Cd) an industrial poison present abundantly in the environment, causes human toxicity by an inflammatory process. Chronic exposure of cadmium can cause a number of molecular lesions that could be relevant to oncogenesis, through indirect or epigenetic mechanisms, potentially including abnormal activation of oncogenes and suppression of apoptosis by depletion of antioxidants. As induction of cyclooxygenase (COX)-2 is linked to inflammatory processes, use of luteolin, epiafzelechin, and albigenin alone or in different combinations may be used as anti-inflammatory therapeutic agents. Methods: We, herein, performed in silico experiments to check the binding affinity of phytochemicals and their therapeutic effect against COX-2 in cadmium administered rats. Wistar albino rats were given phytochemicals in different combinations to check their anti-inflammatory activities against cadmium intoxication. The level of alanine aminotransferases (ALT), 4-hydroxynonenal (4HNE), 8-hydroxy-2-deoxyguanosine (8-OHdG), tumor necrosis factor-alpha (TNF-α), isoprostanes (IsoP-2α), COX-2, and malondialdehyde (MDA) were estimated with their respective ELISA and spectrophotometric methods. Results: The generated results show that phytocompounds possessed good binding energy potential against COX-2, and common interactive behavior was observed in all docking studies. Moreover, the level of ALT, 4HNE, 8-OHdG, TNF-α, IsoP-2α, malondialdehyde, and COX-2 were significantly increased in rats with induced toxicity compared to the control group, whereas in combinational therapy of phytocompounds, the levels were significantly decreased in the group. Discussion: Taken together, luteolin, epiafzelechin, and albigenin can be used as anti-inflammatory therapeutic agents for future novel drug design, and thus it may have therapeutic importance against cadmium toxicity.

Effect of kiln dust from a cement factory on growth of Vicia faba L.

This study was undertaken to study the effects of different amounts of kiln dust mixed with soil on the seed germination, plant growth, leaf area and water content of Vicia faba cv. Eresen. The reason for this was that cement kiln dust generated as a by-product from the cement factories is rich in potassium, sulfate and other compounds. This product becomes a serious problem when it comes in contact with water. The dust was collected from a cement factory located in Canakkale. Various elements such as Al, Co, Mo, Ca, B, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Se and Zn were determined both in soil as well as kiln dust. Kiln dust was mixed with soil in pots (20 cm diameter) to make seven different treatments varying from 15 to 105 g kiln dust kg(-1) of soil. The experiment lasted for 4 months. Seeds of V faba were sown in the pots filled with mixtures of preanalysed kiln dust and soil. Germination was high in the pots with a lower treatment of cement kiln dust. However, lower germination rates were observed in the pots mixed with the highest and the medium amounts of cement kiln dust. Plants growing in the soil including 15 g kiln dust showed better performance in length as compared to control. Leaf area increased with increase in cement kiln dust content up to 60 g kiln dust kg(-1) of soil, but declined after 75 g kg(-1). Water content of leaves (mg cm(-2) leaf area) was found to be constantly decreasing with respect to increasing cement kiln content in the pots. Differences between the averages were evaluated by Tukey test and results were found to be significant.

Biodiversity and land degradation in the lower Euphrates subregion of Turkey.

Atotal of 107 plant taxa were determined in this study, 24 being new records for the area. Out of 813 plant taxa reported from the study area 100 species couldn't be verified. The number of endemics in the study area is around 46. The majorfamilies and genera are Asteraceae, Fabaceae, and Poaceae and Astragalus, Euphorbia, Allium and Trigonella. The area shows a relatively rich and highly diverse fauna. For terrestrial vertebrate species peculiarly showing marginal distribution, this area forms their northernmost distributional limits. Avifauna along the Euphrates valley is quite rich with 207 species. Globally threatened species, Geronticus eremita (Waldrapp), has been observed locally in the area. Many macromammal species once common have gone extinct. Out of 18 lizard species, 3 lizards are known only from the study area. There are 20 species of snakes, one being exclusively endemic to the study area. Nearly 30 fish species are found in Euphrates system. Very scanty information is available for the invertebrate fauna except for some groups of Mollusca and Arthropoda. The biodiversity of the area is under threat from recent developments and abiotic interferences.

Pharmacoinformatics approaches in the discovery of drug-like antimicrobials of plant origin.

Medicinal plants have served as an important source for addressing the ailments of humans and animals alike. The emergence of advanced technologies in the field of drug discovery and development has helped in isolating various bioactive phytochemicals and developing them as drugs. Owing to their significant pharmacological benefits and minimum adverse effects, they not only serve as good candidates for therapeutics themselves but also help in the identification and development of related drug like molecules against various metabolic and infectious diseases. The ever-increasing diversity, severity and incidence of infectious diseases has resulted in an exaggerated mortality and morbidity levels. Geno-proteomic mutations in microbes, irrational prescribing of antibiotics, antimicrobial resistance and human population explosion, all call for continuous efforts to discover and develop alternated therapeutic options against the microbes. This review article describes the pharmacoinformatics tools and methods which are currently used in the discovery of bioactive phytochemicals, thus making the process more efficient and effective. The pharmacological aspects of the drug discovery and development process have also been reviewed with reference to the in silico activities. Communicated by Ramaswamy H. Sarma.

Vulnerability of municipal solid waste: An emerging threat to aquatic ecosystems.

Dumping waste materials into aquatic ecosystems leads to pollution, which directly and indirectly poses a danger to all life forms. Currently, huge quantities of wastes are generated at a global scale with varying constituents, including organic fractions, emerging contaminants and toxic metals. These wastes release concentrated contaminants (leachates), which are lethal for all ecosystems around the globe because they contain varying concentrations of chemical constituents with BOD5 and COD in the order of 2 × 104-2.7 × 104 mg/L, and 3.4 × 104-3.8 × 104 mg/L, respectively. Herein, in-depth knowledge of municipal solid waste dumping into the aquatic ecosystems, changes in physicochemical characteristics, availability of in-/organic contaminants, and long-term unhealthy effects are presented. Moreover, an attempt has been made here to summarize the facts related to identifying the deadly impacts of waste on different ecosystem components. The unresolved challenges of municipal waste management are emphasized, which will help employ suitable waste management techniques and technologies to conserve the everlasting freshwater resources on earth.

Arsenic and Human Health: Genotoxicity, Epigenomic Effects, and Cancer Signaling.

Arsenic is a well-known element because of its toxicity. Humans as well as plants and animals are negatively affected by its exposure. Some countries suffer from high levels of arsenic in their tap water and soils, which is considered a primary arsenic-linked risk factor for living beings. Humans generally get exposed to arsenic by contaminated drinking waters, resulting in many health problems, ranging from cancer to skin diseases. On the other hand, the FDA-certified drug arsenic trioxide provides solutions for various diseases, including several types of cancers. This issue emphasizes the importance of speciation of the metalloid elements in terms of impacts on health. When species get exposed to arsenic, it affects the cells altering their involvement. It can lead to abnormalities in inflammatory mechanisms and the immune system which contribute to the negative impacts generated on the body. The poisoning originating from arsenic gives rise to various biological signs on the body which can be useful for the diagnosis. It is important to find true biomarkers for the detection of arsenic poisoning. In view of its application in medicine and biology, studies on understanding the biological activity of arsenic have increased. In this review, we aim at summarizing the current state of knowledge of arsenic and the mechanism behind its toxicity including genotoxicity, oxidative insults, epigenomic changes, and alterations in cellular signaling.

Molecular Biology of Cadmium Toxicity in Saccharomyces cerevisiae.

Cadmium (Cd) is a toxic heavy metal mainly originating from industrial activities and causes environmental pollution. To better understand its toxicity and pollution remediation, we must understand the effects of Cd on living beings. Saccharomyces cerevisiae (budding yeast) is an eukaryotic unicellular model organism. It has provided much scientific knowledge about cellular and molecular biology in addition to its economic benefits. Effects associated with copper and zinc, sulfur and selenium metabolism, calcium (Ca2+) balance/signaling, and structure of phospholipids as a result of exposure to cadmium have been evaluated. In yeast as a result of cadmium stress, "mitogen-activated protein kinase," "high osmolarity glycerol," and "cell wall integrity" pathways have been reported to activate different signaling pathways. In addition, abnormalities and changes in protein structure, ribosomes, cell cycle disruption, and reactive oxygen species (ROS) following cadmium cytotoxicity have also been detailed. Moreover, the key OLE1 gene that encodes for delta-9 FA desaturase in relation to cadmium toxicity has been discussed in more detail. Keeping all these studies in mind, an attempt has been made to evaluate published cellular and molecular toxicity data related to Cd stress, and specifically published on S. cerevisiae.

Nitrogen mineralization in a high altitude ecosystem in the mediterranean phytogeographical region of Turkey.

Interrelations exist in the terrestrial ecosystems between the plant type and characteristics of nutrient uptake. Annual net nitrogen mineralization in soils of different plant communities in the high altitude zone of Spil mountain located in the Mediterranean phytogeographical region of Turkey was investigated throughout one year by field incubation method. Seasonal fluctuations resulting from field incubation were markedly higher in autumn and spring than summer. These are mainly associated with the changes in soil moisture being at minimum in the Mediterranean summer. A significant correlation was developed between the net Nitrate (kg NO3(-)-N ha week(-1)) production and soil water content (p<0.05; r = 0.316 in soil of 0-5 cm; r = 0.312 in soil of 5-15 cm). The results showed that the annual productivity of nitrogen mineralization shows different values depending on communities. Annual net ammonium (NH4(+)-N) production in the soils of each community was negatively estimated. However annual net nitrate (NO3(-)-N) production (0-15 cm) was higher in grassland (27.8 kg ha y(-1)) and shrub (25.0 kg ha y(-1)) than forest (12.4 kg ha y(-1)) community. While annual net N(min) values were close to each other in grassland (14.5 kg ha y(-1)) and shrub (14.1 kg ha y(-1)), but negative in forest community (-3.6 kg ha y(-1)). The reasons for these differences are discussed.

Forest diversity, climate change and forest fires in the Mediterranean region of Turkey.

This paper reviews the forest resources in Turkey in the light of published literature and summarises extensive fieldwork undertaken in the Mediterranean phytogeograhical region of Turkey. The issues of landscape change and the associated drivers are addressed and the threats to the forest diversity are considered. It notes the impacts of climate change and forest fires and attemepts have been made to put forth future options for sustainable forest development.

Plant distribution-altitude and landform relationships in karstic sinkholes of Mediterranean region of Turkey.

The purpose of this study was to investigate the relationships between the plant distribution and the altitude-shape-size characteristics of sinkholes, and the landform characteristics inside sinkholes in the Mediterranean region of Turkey. Block kriging, Factor analysis, Cluster Analysis and Detrended Correspondence Analysis were performed. The sinkhole type and altitudinal zone were found to be the significant factors affecting the plant distribution. However, the sinkhole type was more important than the altitudinal zone. Hence, the sinkholes were first subdivided into groups according to types and then the groups were divided into subgroups according to the altitudinal zones. Consequently, 4 groups were defined; A-type sinkholes [1400-1550 m (A1), 1550-1700 m (A2)] and B-type sinkholes [1400-1550 (B1), 1550-1700 m (B2)]. The B-type was wider vertically and shorter horizontally than A-type sinkholes. Significant differences were found between the plant distribution and slope position inside the sinkholes. Plant distribution in the lower slopes was different from that in the flats and ridges in the B1 sub-type of B-type. Plant distribution in B2 subtype was different among the slope positions (ridge, middle slope, lower slope, and flat). Although distribution of plants is different in different parts (ridges, upper slope, middle slope, lower slope and basal flats) of A sinkhole, the differences between the parts of intermediate slope position are not significant. A high plant variability along short distances in the sinkholes was observed in the study area. That is why the site of sinkholes have a big potential for the distribution of many species. Hence, the area must be separated as strictly protected zone.

Carolina poplar (Populus x canadensis Moench) as a biomonitor of trace elements in Black Sea region of Turkey.

In this study the leaves, bark and the soil supporting Populus x canadensis Moench were tested as a possible biomonitor of trace element pollution in the Middle Black Sea region of Turkey. The investigations were carried out at 23 sites. The leaves, bark and soil were analyzed for Pb++, Cd++, Fe++, Cu++ and Zn++ contents. The values of Pb++, Cd++, Fe++, Cu++ and Zn++ in the leaves varied between 14.5-40.0, 0.5-1.5, 135-486, 5.0-14.0 and 43-246 ppm, respectively. In the bark the values were between 15.5-36.5 (Pb++), 1.5-2.0 (Cd++), 39-575 (Fe++), 5.0-14.0 (Cu++) and 40.0-1468 ppm (Zn++), whereas in the soil values for Pb++ were 1.0-4.1 ppm, for Cd++ 0.2 ppm, for Fe++ 0.6-1.8 ppm, for Cu++ 0.1-0.9 ppm and for Zn++ 0.1-1.9 ppm. A positive correlation was found between traffic density and the amount of Pb++, Fe++ and Cu++ in leaves, while a negative correlation was documented for Cd++ and Zn++. In the bark samples there was a positive correlation between traffic density and Pb++, and a negative one with Cd++, Fe++, Cu++ and Zn++. A positive correlation was determined between traffic density and the amount of Pb++, Fe++, Cu++ and Zn++ in soil. However, the amount of Cd++ was 0.2 ppm and no relationship between Cd++ and traffic density was observed.

Ecophysiological responses of some maquis (Ceratonia siliqua L., Olea oleaster Hoffm. & Link, Pistacia lentiscus and Quercus coccifera L.) plant species to drought in the east Mediterranean ecosystem.

The objective was to examine the adaptation strategies of four maquis species to drought prone environments; typical of the east Mediterranean area in degraded and healthy sites in Turkey. A comparison made between sites for Pistacia lentiscus and Quercus coccifera shows higher net daily photosynthesis in the degraded site, when compared with the healthy site; but Ceratonia siliqua and Olea oleaster exhibited no difference in their photosynthetic activity in environmentally contrasting conditions. The pattern of daily transpiration shows higher values in the degraded site in the case of P. lentiscus and Q. coccifera, while no site effect was observed for C. siliqua and O. oleaster. In the case of Q. coccifera, a behavior similar to C. siliqua was observed. A comparison made between C. siliqua and O. oleaster to observe seasonal differences in daily patterns of net photosynthesis and transpiration reveals that Q. coccifera had the highest water use efficiency (slope= 2.88; r2 = 0.61), followed by C. siliqua (slope = 2.74; r2 = 0.7), P. lentiscus (slope = 2.56; r2 = 0.52) and O. oleaster (slope = 2.40; r2 = 0.78). Olea oleaster and P. lentiscus performed as a drought tolerant species, being more resistant to aridity and thus indicative of the degradation state of the site. Ceratonia siliqua and Q. coccifera were found avoiding drought by adopting first a water-spending strategy, and then a water-saving strategy.