Halophytic crops for a salinising world

Soil salinisation is an increasing problem for agriculture, affecting the most productive crop areas in the world those cultivated under irrigation in arid and semi-arid regions. In addition, a significant fraction of the world's land surface is naturally saline and is not available for agriculture. Cultivation of these salinised areas, if possible, would contribute to the increase in food production needed in the next few decades to feed a growing world population. Unfortunately, our present crops are all salt-sensitive, to a greater or lesser degree, and classical breeding has not succeeded in improving their resistance to salinity. Similarly, genetic engineering approaches have not yet delivered commercial salt-tolerant 'biotech' (GM) crops. Yet a small percentage (ca. 0.25%) of wild angiosperm species halophytes are adapted to saline soils in their natural habitats, and many are able to complete their life cycle at salinity levels similar to, or even higher than sea water. Halophytes could be cultivated in salinised land already lost for agriculture, and also in naturally saline, marginal soils, using brackish water, reclaimed industrial/urban waste water, or even sea water for irrigation. Most important, this 'saline agriculture' will not compete with conventional crops for increasingly scarce resources, such as fertile land and good-quality irrigation water. Several salt-tolerant taxa are being investigated as potential 'new' halophytic crops and others can be developed in the near future, to be used, for example: i) as human food or for animal feed; ii) for production of biofuels: biomass generation for bioethanol, and biodiesel obtained from oleaginous seeds; iii) for the production of secondary metabolites with medical, nutraceutical, cosmetic or other industrial applications; iv) as new ornamental plants, for gardening and landscape architecture. As the crop potential of many of these species is unknown and some may have undesirable agronomic characteristics, we propose that more effort should be invested in the domestication of promising halophytic taxa, establishing breeding programmes to transform these amazing wild plants into useful crops.Boscaiu Neagu, MT.; Vicente Meana, Ó. (2013). Halophytic crops for a salinising world. Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca : Horticulture. 70(1):1-9. doi:10.15835/buasvmcn-hort:9349S1970

ENZYMATIC ACTIVITY AND SOLUBLE PROTEIN CONTENT IN SEEDLINGS OF CALENDULA OFFICINALIS L. UNDER SALT STRESS

[EN] Enzymatic activity and soluble protein content in relation to salt stress tolerance were investigated in Calendula officinalis seedlings after 24 days of treatment with different salt treatments, including NaCl, CaCl2, MgCl2 and mixtures of them. The marigold seedlings were used in order to investigate the possible salt-inducible responses and the possible alleviative role of calcium and magnesium salts in respect with adverse salinity conditions. Activity of superoxide dismutase (SOD; EC 1.15.1.1) and peroxidase (POD; EC 1.11.1.7) generally slightly decreased under salt treatments, with minor variations from the value recorded for control series and within applied treatments. Catalase (CAT; EC 1.11.1.6) activity was stimulated by NaCl salinity and MgCl2 addition; its activity was found to be lowest under calcium and magnesium chloride treatments solelyOprica, L.; Vicente Meana, Ó.; Boscaiu Neagu, MT.; Grigore, MN. (2016). ENZYMATIC ACTIVITY AND SOLUBLE PROTEIN CONTENT IN SEEDLINGS OF CALENDULA OFFICINALIS L. UNDER SALT STRESS. Journal of Plant Development (Online). 23:71-79. http://hdl.handle.net/10251/91887S71792

Mechanisms of Response to Salt Stress in Oleander (Nerium oleander L.)

[EN] mulation, activation of antioxidant systems), have been studied in Nerium oleander, a xerophytic species widely used as ornamental. Salt strongly inhibited growth, but the plants survived one month in the presence of 800 mM NaCl, indicating that the species is also relatively resistant to salt stress. Salt induced a slight increase in the levels of proline, glycine betaine and soluble sugars; the latter compounds showed much higher absolute contents, suggesting a functional role in osmotic adjustment, and the presence of constitutive mechanisms of response to salt stress. High salinity generated oxidative stress in the plants, as shown by the increase of malondialdehyde levels. Antioxidant systems, enzymatic andKumar, D.; Al Hassan, M.; Vicente Meana, Ó.; Agrawal, V.; Boscaiu Neagu, MT. (2016). Mechanisms of Response to Salt Stress in Oleander (Nerium oleander L.). BULLETIN OF UNIVERSITY OF AGRICULTURAL SCIENCES AND VETERINARY MEDICINE. 73(2):249-251. doi:10.15835/buasvmcn-hort:12287S24925173

Seasonal variation in proline contents in several halophytes from a littoral salt marsh in Alicante (SE Spain)

[EN] In the present study, we have investigated spatial and temporal changes in Pro levels in several monocotyledonous and dicotyledonous halophytes growing in a littoral salt marsh located near the city of Alicante (SE Spain).Supported by grants from the Spanish Ministry of Science and Innovation, with contribution from the European Regional Development Fund (project CGL2008–00438/BOS) to O.V., and from Polytechnic University of Valencia (programme ‘PAID-06–09’) to M.B. M.-N.G. acknowledges the support provided by COST Action FA0901 for his stay in Valencia in the frame of a Short Term Scientific Mission, and by the Romanian POSDRU/89/1.5/S/49944 project “Developing the innovation capacity and improving the impact of research through post-doctoral programmes”.Marius-Nicusor, G.; Boscaiu Neagu, MT.; Vicente Meana, Ó. (2011). Seasonal variation in proline contents in several halophytes from a littoral salt marsh in Alicante (SE Spain). Ecological Questions. 14:15-16. https://doi.org/10.12775/v10090-011-0003-xS15161

Responses to Drought and Salinity in the Endangered Species Ligularia sibirica (L.) Cass

[EN] The negative effects of environmental stress factors on plant distribution and survival are increasing due to climate change and anthropogenic activities. We have analysed some responses to abiotic stress in Ligularia sibirica, a postglacial relict that is critically endangered in Europe. L. sibirica seedlings were subjected to water or salt stress treatments in the greenhouse. After the treatments, plant material was harvested and several growth parameters were measured; leaf contents of common osmolytes, the degree of oxidative stress affecting the plants and the level of antioxidant phenolic compounds were also determined. Both, drought and, especially, salt stress had a negative effect on the growth of L. sibirica plants. Treated plants showed an increase in proline (Pro) and total soluble sugars (TSS) levels, stronger under salt stress. Malondialdehyde (MDA, an oxidative stress biomarker) contents almost doubled, and antioxidant phenolics increased significantly in salt-stressed, but not in water-stressed plants. Pro accumulation can be used as a salt and drought stress biomarker in L. sibirica and, together with TSS, likely contributes to osmotic adjustment under stress. Increase of antioxidant phenolics appears to partly compensate the salt-induced generation of oxidative stressMatei, AN.; Al Hassan, M.; Boscaiu Neagu, MT.; Alexiu, V.; Vicente Meana, Ó. (2016). Responses to Drought and Salinity in the Endangered Species Ligularia sibirica (L.) Cass. BULLETIN OF UNIVERSITY OF AGRICULTURAL SCIENCES AND VETERINARY MEDICINE. 73(2):252-253. doi:10.15835/buasvmcn-hort:12286S25225373

Biotechnological improvement of drought and salt tolerance of crops:a new paradigm for increasing food production

Vicente Meana, Ó.; Al Hassan, M.; Boscaiu Neagu, MT. (2015). Biotechnological improvement of drought and salt tolerance of crops:a new paradigm for increasing food production. Studia Universitatis Babes-Bolyai. Biologia. 60:73-74. http://hdl.handle.net/10251/79132S73746

Ecological notes in Mediterranean halophytes. Towards an integrative approach

[EN] In this work we try to propose an integrative manner in which halophytes could be ecologically approached. Taking into considerations many factors related to environmental conditions, as well as corresponding adaptations in halophytes, we can obtain a good picture of interrelationships established within a typical ecosystem.Supported by grants from the Spanish Ministry of Science and Innovation, with contribution from the European Regional Development Fund (project CGL2008–00438/BOS) to O.V., and from Polytechnic University of Valencia (programme ‘PAID-06–09’) to M. B. M.-N. G. acknowledges the support provided by COST Action FA0901 for his stay in Valencia in the frame of a Short Term Scientific Mission, and by the Romanian POSDRU/89/1.5/S/49944 project “Developing the innovation capacity and improving the impact of research through post-doctoral programmes”.Marius Nicusor, G.; Boscaiu Neagu, MT.; Vicente Meana, Ó. (2011). Ecological notes in Mediterranean halophytes. Towards an integrative approach. Ecological Questions. (14):11-13. https://doi.org/10.12775/v10090-011-0002-yS11131

Expression of the Vacuolar Na+/H+ Antiporter Gene (NHX1) in Three Plantago Species Differing in Salt Tolerance

[EN] We have isolated full-length cDNA clones of the NHX1 gene – encoding the vacuolar Na+ /H+ antiporter – from three Plantago species (P. crassifolia, P. coronopus and P. major) differing in salt tolerance. A phylogenetic tree of their deduced protein sequences and those of NHX1 antiporters previously isolated from other species suggested the presence of some structural features characteristic of the proteins of salt tolerant taxa. The expression patterns of the NHX1 genes in the presence of salt correlated with the relative degree of salt tolerance of the three species: no induction was detected in the least tolerant P. major – and in the glycophyte A. thaliana – and the highest and quickest induction was observed in the most tolerant P. crassifolia. These data support the hypothesis that the NHX1 antiporters play a functional role in the mechanisms of salt tolerance in plants.Al Hassan, M.; Daniso, E.; Boscaiu Neagu, MT.; Vicente Meana, Ó. (2015). Expression of the Vacuolar Na+/H+ Antiporter Gene (NHX1) in Three Plantago Species Differing in Salt Tolerance. Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca : Horticulture. 72(2):441-442. doi:10.15835/buasvmcn-hort:11544S44144272

Drought Responses in Six Hazelnut (Corylus avellana L.) Cultivars

[EN] Drought is one of the major causes of reduction of crop yields worldwide, a problem that will increase in the next decades due to climate change. We describe here an initial attempt to define biochemical markers associated to water stress in several hazelnut cultivars, by measuring the levels of common osmolytes and the generation of secondary oxidative stress, in plants subjected to water stress, and after recovery from the stress treatment. Proline (Pro) appears to be a reliable marker in this species, as its accumulation in leaves correlates well with the degree of stress affecting the plants. Differences between cultivars in relative Pro accumulation and oxidative stress suggested that some cultivars are more tolerant than others and could be selected for cultivation in drought-affected areas.Shahi-Gharahlar, A.; Fatahi, MR.; Zamani, Z.; Al Hassan, M.; Boscaiu Neagu, MT.; Vicente Meana, Ó. (2016). Drought Responses in Six Hazelnut (Corylus avellana L.) Cultivars. BULLETIN OF UNIVERSITY OF AGRICULTURAL SCIENCES AND VETERINARY MEDICINE. 73(2):259-261. doi:10.15835/buasvmcn-hort:12288S25926173

Opportunistic germination behaviour of Gypsophila (Caryophyllaceae) in two priority habitats from semi-arid Mediterranean steppes

[EN] Gypsophila tomentosa and G. struthium are closely related species, characteristic of two European priority habitats, salt and gypsum inland steppes, respectively. Germination strategies of the two taxa were investigated in plants from two nearby populations, growing under the same climatic conditions but on different types of soil, and belonging to different plant communities. Their germination patterns were studied at five constant temperatures in darkness: 5 degrees C, 10 degrees C, 15 degrees C, 20 degrees C and 25 degrees C, and the base temperature and the thermal time requirement were calculated. As the distribution area of both species is subjected to a Mediterranean continental climate with significant differences between day and night, the possible preferences for an alternating temperature regime (25/10 degrees C) were contrasted, as well as the influence of cold stratification and freezing. The effects on seed germination of light at constant 20 degrees C and a 12/12 h photoperiod were also compared in the two species. The main conclusions of the work are the similarity of behaviour of both species, with an absence of seed dormancy, their opportunistic germination strategy, and water availability as the principal limitation to seed germination and plant establishment. The base temperature and thermal time indicate higher competitiveness of G. struthium at low temperatures, but seed germination of G. tomentosa is the most efficient at temperatures higher than 13.3 degrees C. Optimal temperature and illumination conditions for nursery propagation depend on the species. The high viability of seeds observed after freezing prove the orthodox character of these seeds, providing additional information for long term seed conservation procedures.The experiments were conducted at the Botanical Garden of the University of Valencia and were co-financed by the European Union Interreg Project GENMEDOC (Création d’un reseau de centres de conservation du matériel génétique de la flore des régions méditerranéennes de l’espace MEDOCC), project number 2003-03-4.1-E-060, and Generalitat Valenciana (Consellería de Medio Ambiente, Agua, Urbanismo y Vivienda).Moruno, F.; Soriano, P.; Vicente Meana, Ó.; Boscaiu Neagu, MT.; Estrelles, E. (2011). Opportunistic germination behaviour of Gypsophila (Caryophyllaceae) in two priority habitats from semi-arid Mediterranean steppes. NOTULAE BOTANICAE HORTI AGROBOTANICI. 39:18-23. doi:10.15835/nbha3916078S18233