Halophytes and climate change: adaptive mechanisms and potential uses最新文献

{"title":"Lipids in halophytes: stress physiology relevance and potential future applications.","authors":"B. Duarte, A. Matos, J. Marques, I. Caador","doi":"10.1079/9781786394330.0359","DOIUrl":"https://doi.org/10.1079/9781786394330.0359","url":null,"abstract":"Abstract\u0000 The present environmental conditions impose serious constraints on typical cultivar farming. Halophytes are known to be highly resistant to harsh environments, withstanding drought and salinity while maintaining positive biomass production rates. It is known that, in adapting to adverse conditions, plants suffer some lipid remodelling to maintain membrane stability and the efficiency of the metabolic processes associated with these systems. This thus opens a new door for potential biotechnological applications based in added-value fatty acids (FAs) produced by halophytes. These can be used in the food industry sector, as some halophytes show very interesting concentrations of essential omega 3 and 6 FAs, even under seawater irrigation schemes. Another physiological consequence of growing under stress conditions is the accumulation of storage lipids in the highly productive photosynthetic organs. Along with seeds, these are the major sinks of triacylglycerols (TAGs) found in halophytes. Under stress conditions, halophytes are able to maintain their productivity while increasing the TAG content in their photosynthetic leaves, with high levels of saturated FAs; this would be useful in biodiesel production. Halophytes can, therefore, be considered sources of added-value FAs with applications in both food production and biotechnology.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114279270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ROS signalling, and antioxidant defence network in halophytes.","authors":"E. Surwka, D. Latowski, M. Libik-Konieczny, Z. Miszalski","doi":"10.1079/9781786394330.0179","DOIUrl":"https://doi.org/10.1079/9781786394330.0179","url":null,"abstract":"Abstract\u0000 Halophytes have evolved a range of adaptations to tolerate disturbances in reactive oxygen species (ROS) homeostasis caused by high salinity alone or in combination with other stresses. Singlet oxygen (1O2), superoxide anion (O2.-), hydroxyl radical (OH.) and hydrogen peroxide (H2O2) are the major ROS generated during plant metabolism. The main sources of ROS are chloroplasts, mitochondria, peroxisomes, apoplasts, plasma membranes and cell walls. Regulation of ROS levels in these compartments plays a key role in response to salt stress. Many various defence strategies have been discovered in chloroplasts. These include stress-avoidance mechanisms (e.g. alteration in proteins involved in electron transport chains, changes in lipid composition, harmless dissipation of excess energy) and ROS-scavenging systems (enzymatic and non-enzymatic antioxidants, some osmoprotectants). The efficient antioxidant mechanisms in halophytes can prepare plants to cope with subsequent stress factors by inducing a signal to activate the stress response and suppress the oxidative burst within a short time after the stimulus action. The interrelationship between ROS scavengers leads to spatio-temporal modulation of the ROS signalling network. Although the ROS level is modulated by both: (1) specific mechanisms enabling delay/reduction in the oxidative burst; and (2) ROS-scavenging systems in each cell compartment, interactions between cell organelle and cytoplasm are critical in adjusting redox homeostasis, and the ROS signalling network plays a role in inducing salinity tolerance at the cellular and whole-plant levels.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115500916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antioxidant defence in halophytes under high salinity.","authors":"K. Neeraj, L. Shubham, K. Ashwani, K. Pratima, A. Mann, D. Sarita, P. Pooja, K. Anita, R. Babita","doi":"10.1079/9781786394330.0196","DOIUrl":"https://doi.org/10.1079/9781786394330.0196","url":null,"abstract":"Abstract\u0000 Understanding the various mechanisms of salt-stress tolerance is important for crop improvement, especially when approximately 20% of agricultural land and 50% of crop land in the world is under salt stress. Stomatal closure due to salt stress reduces the CO2:O2 ratio inside the leaf tissues and inhibits CO2 fixation. This inhibition leads to over-reduction of the photosynthetic electron transport chain and causes the generation of reactive oxygen species (ROS) such as singlet oxygen (1O2), superoxide anion (O2.-), hydrogen peroxide (H2O2) and hydroxyl radical (OH.). These ROS are responsible for various stress-induced damages to macromolecules and ultimately to cellular structure. Hence, to avoid excessive ROS accumulation during stress and maintain the correct levels of ROS for signalling, plants possess a complex antioxidant defence system including non-enzymatic antioxidants such as ascorbic acid, glutathione, tocopherols and carotenoids; and enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX) and ascorbate peroxidase (APX). Although ROS production and defence mechanisms are common in glycophytes and halophytes, detoxification strategies may vary in response to salinity with regard to total antioxidant activity and type of iso-enzymes expressed. In this chapter we describe salinity, the classification of saline soils, genetic variability within halophytes, sources and overproduction of ROS under high-salinity conditions, the antioxidant defence system, enzymatic antioxidant system and nonenzymatic antioxidant system.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123184400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Halophytic vegetation in south-east Europe: classification, conservation and ecogeographical patterns.","authors":"Z. Stevanović, S. Aćić, D. Stešević, Milica Luković, U. Šilc","doi":"10.1079/9781786394330.0055","DOIUrl":"https://doi.org/10.1079/9781786394330.0055","url":null,"abstract":"Abstract\u0000 Halophytic vegetation is very complex and diverse, and the main factors for its development are salinity and moisture. Investigations into different types of halophytic vegetation have been compiled in vegetation databases as scientific tools for classification analyses and interpretation of European saline habitats. Two major types of halophytic habitats exist in Europe: inland (continental) and coastal (maritime), with different halophytic plant communities. Inland halophytic vegetation is classified into two main classes: Thero-Salicornietea: annual succulent vegetation of extreme salt-rich soils, and Festuco-Puccinellietea: saline steppe grasslands. Coastal halophytic vegetation is represented by five classes: Saginetea maritimae: ephemeral vegetation, Crithmo-Staticetea: vegetation of salt-sprayed coastal cliffs, Cakiletea maritimae: pioneer vegetation of sandy and shingle beaches, Ammophiletea: tall-grass vegetation on mobile coastal dunes and Helichryso-Crucianelletea maritimae: dwarf shrub and grassland vegetation on stabilized dunes. Saline habitats are globally endangered; major threats are thought to be ploughing and melioration, as well as abandonment of traditional management (grazing and mowing), eutrophication and ruderalization. Several species of continental and maritime halophytic vegetation are listed in Annex I of the Habitats Directive, and saline habitats are part of the Natura 2000 network (Council Directive 92/43/EoEC 1992).","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128351073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intra-habitat variability of halophytic flora of north-west India.","authors":"D. Sarita, K. Ashwani, A. Mann, S. S. Arya, C Gurdev, K. Neeraj, K. Anita, P. Pooja, R. Babita, K. Arvind","doi":"10.1079/9781786394330.0038","DOIUrl":"https://doi.org/10.1079/9781786394330.0038","url":null,"abstract":"Abstract\u0000 The growth and ion-accumulating characteristics of different plant species native to saline-arid areas vis-à-vis the ionic status of their rhizospheric soils are important factors to consider when studying the survival of plant species under harsh conditions. A survey of saline areas in Haryana (CCS Haryana Agricultural University and Central Institute for Research on Buffaloes at Hisar) and Rajasthan (Lunkaransar in Bikaner, Sambhar Lake, Jaipur and Gangani-Kaparda at Jodhpur) was done to explore the variability in halophytic species in different arid and saline regions. It was observed that 44 species spread over 16 families of Angiosperms (i.e. Chenopodiaceae, Mimosaceae, Poaceae, Capparidaceae, Portulacaceae, Tamaricaceae, Fabaceae, Caesalpiniaceae, Aizoceae, Asteraceae, Salvadoraceae, Asclepiadaceae, Boraginaceae, Solanaceae, Amaranthaceae and Cyperaceae) were growing across these locations with most species from the Chenopodiaceae family. Among these highly flourishing species were Salsola baryosma, Suaeda fruticosa, S. nudiflora and Saccharum munja, producing the highest biomass per unit area of land. The rhizospheric soil of different locations was saline to highly saline. While exploring the ionic homeostasis, it was found that most ions (e.g. Na+, K+, Ca2+, Mg2+, Cl- and SO42-) were accumulating more in their leaves than in their stems, which may be a survival mechanism of these halophytic species under worse conditions of salinity. In terms of soil habitat across these surveyed regions, the rhizospheric salinity is patchy and supports both facultative halophytes and glycophytes.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124163705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defining halophytes: a conceptual and historical approach in an ecological frame.","authors":"M. Grigore","doi":"10.1079/9781786394330.0003","DOIUrl":"https://doi.org/10.1079/9781786394330.0003","url":null,"abstract":"Abstract\u0000 Halophytes have certainly been recognized since the beginning of the 18th century, but subtle earlier allusions to salt-tolerant plants can be found back to 1500. By the time of the French Encyclopédie (1751-1765), and Goethe (1786), consistent data about halophytes had already been accumulated. Halophytes were brought to scientific attention through the classic and iconic papers of the German botanist Schimper, and especially those of the Danish plant ecologist Warming. However, their definitions remain controversial; the lack of a unique definition is related mainly to the complex features of this ecological group of plants. There are many definitions of halophytes, and some reflect the scientific background of the researchers who defined them. The 'historical' evolution of a definition can be delineated, and it especially reflects the progress of accumulating knowledge about halophyte biology. The definition of halophytes is thus manifold. The criteria and the historical context in which their definitions occurred and developed are discussed in detail in this chapter. Special attention is given to textual analysis that reveals the convergent approaches of researchers who used different languages. Ecological perspectives in defining halophytes suggest that, although they in fact represent a large ecological group of plants, their common xeromorphic nature must be universally recognized.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125199478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practical uses of halophytic plants as sources of food and fodder.","authors":"T. Centofanti, G. Bauelos","doi":"10.1079/9781786394330.0324","DOIUrl":"https://doi.org/10.1079/9781786394330.0324","url":null,"abstract":"Abstract\u0000 Halophytes are plants that are adapted to saline soils in their natural habitats because they are salt tolerant. They are found in a range of environments with varied salinity and climatic conditions. These plant species can be irrigated with saline water and cultivated on saline soils that are unsuitable for commercial crops. Halophytes are rich in nutrients, such as antioxidants, fatty acids and amino acids, and many species have been used traditionally as herbs and vegetables, feed and fodder. Therefore, halophytes are considered one of the alternative solutions to problems related to food security, fresh water scarcity, salinization and diversification of diets for healthier nutrition. However, despite the promising future for multiple uses of halophytes, many problems related to halophyte cultivation for human and animal consumption and their commercialization have still not been tackled. This chapter is intended to provide an overview of the development of halophytes as vegetable, feed and fodder, and to highlight the importance of creating a demand in the marketplace for halophyte consumption.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115856203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"South African salt marshes: ecophysiology and ecology in the context of climate change.","authors":"P. T. Tabot, J. B. Adams","doi":"10.1079/9781786394330.0069","DOIUrl":"https://doi.org/10.1079/9781786394330.0069","url":null,"abstract":"Abstract\u0000 This paper reviews the distribution, zonation and ecophysiological tolerances of salt marsh plants in South Africa. In South Africa salt marsh covers 11,788.8 ha with the largest areas occurring in the Berg, Olifants, Orange and Langebaan Estuaries. The changing climate necessitates in-depth studies on the responses of these plants so that we can understand and predict future changes in their abundance and diversity. Responses of salt marsh plants to abiotic stressors are reviewed and it is shown that, on a local ecosystem scale, distribution of species is driven by moisture/inundation levels and salinity gradients. Ecophysiology studies have been completed on at least 15 salt marsh species in South Africa, focusing on the responses of salt marsh plants to various factorial combinations of abiotic stressors. Studies also exist on characterization and zonation of salt marsh habitats and have significantly affected salt marsh management policy. Salt marsh plants respond to osmotic and ionic stress through reduction in growth and increase in root:shoot ratio, ion sequestration and accumulation of ionic and compatible organic solutes for osmoregulation. These responses are similar, whether elicited by soil moisture deficit or salinity, but may vary in intensity. Submergence results in increased cytoplasmic acidosis, membrane lipid peroxidation and a rapid increase in reactive oxygen species. Physiologically, tolerant species respond to submergence by down-regulating metabolism, increased synthesis of antioxidant enzymes and up-regulating compatible osmolytes. This translates into increased species growth. These responses collectively determine salt marsh zonation and are important, especially in the context of climate change.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116180084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morpho-anatomical traits of halophytic species.","authors":"D. Rančić, I. Pećinar, S. Aćić, Z. Stevanović","doi":"10.1079/9781786394330.0152","DOIUrl":"https://doi.org/10.1079/9781786394330.0152","url":null,"abstract":"Abstract\u0000 Some aspects of plant tolerance to salt stress are based on morphological and anatomical traits. Halophytes with different preferences for increased salinity conditions show differences in anatomical features, as a consequence of evolving adaptive responses to salt stress. In this chapter we discuss the general morphological and anatomical structure of plants of saline habitats, aiming to provide a detailed review of literature on typical and special morphological and anatomical characteristics of halophytes. Species in the group most tolerant to saline conditions develop two main strategies for avoiding the toxic effect of salt uptake: dilution of salts by increasing leaf or stem succulence (such as Cakile maritima, Salsola soda, Suaeda maritima, Salicornia fruticosa); and/or or by excreting excess salts from specialized secretory structures such as bladders and salt glands (e.g. Halimione portulacoides, Limonium gmelinii). In addition to succulent and salt-excreting halophytes, other species exhibit various xeromorphic characteristics, similar to plants of drought conditions (thick epidermis covered with cuticle and wax, abundant trichomes, small leaves, presence of bulliform cells, etc.). The latter species have usually developed various salt-exclusion adaptive mechanisms, and are a common flora of saline steppe in Europe (Puccinellia distans, Camphorosma annua, Artemisia santonicum, etc.).","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127526423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elimination of salt by recretion: salt glands and gland-supported bladders in recretohalophytes.","authors":"U. Lttge","doi":"10.1079/9781786394330.0223","DOIUrl":"https://doi.org/10.1079/9781786394330.0223","url":null,"abstract":"Abstract\u0000 Elimination of mineral ions and salts by salt glands and salt hairs is called recretion, which has given the name recretohalophytes to plants using this mechanism for tolerance of salinity. There are about 370 vascular plant species of recretohalophytes comprising about 15% of all halophytes and 0.15% of angiosperms. Their evolutional origin is polyphyletic. Anatomical complexity shows trends from hydathodes to salt glands. There is different complexity between simple epidermal bladders and trichome-like salt hairs concentrating salt in terminal bladder cells. Transport pathways comprise cell-to-cell apoplastic and symplastic transport in salt gland and salt hair complexes, membrane transport by ion transporters and H+-ATPases (eccrine recretion) and possibly vesicle transport (granulocrine recretion). Salt-gland cell cytology is characterized by a very dense cytoplasm enriched in mitochondria, but lacking functional chloroplasts. The plasma-membrane surface is often inflated by a labyrinth of cell wall protuberances, typical of transfer cells. Materials recreted are preferentially Na+ and Cl-. However, many other ions and also some organic solutes may be found. Isolation of salt glands embedded in the epidermis has so far not been achieved, and salt hairs with their glandular stalk cells (which are easier to isolate) have not been used for identifying recretion-specific ion transporters. Nevertheless, transcriptomics and proteomics have been applied to compare plants with differing recretory activity, including specific recretion mutants, to identify transporters putatively involved in recretion. Recretion is under genetic control. Although the number of recretohalophytes among angiosperm halophytes is relatively low (ca 15%), individual recretohalophyte species can play an important role in saline habitats. Ecophysiologically the efficiency of recretion depends on the site characteristics to which plants are adapted. Water loss with the recreted fluid is an ecophysiological challenge. Recretion does not reduce habitat salinity, because recreted salt is recycled to the environment. Recretohalophytes provide multiple services to anthropogenic management of salinity-affected ecosystems under increasingly severe environmental challenges now and in the future of global changes. There are many promising applications of recretohalophytes in saline agriculture. They serve as pasture and fodder plants and have entered human diets. Due to salt recycling they do not appear to be applicable to phytoremediation of salinity but they may clear metals from soils, and may serve as sources of bio-energy and biofuel. Recretohalophyte species can be used in the restoration ecology of deteriorated land. Recretohalophytes provide gene pools for gene engineering and synthetic biology in managing future challenges.","PeriodicalId":285820,"journal":{"name":"Halophytes and climate change: adaptive mechanisms and potential uses","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124334693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}