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Increased Salinity (increased + salinity)
Selected AbstractsPurification and Kinetic Characterization of Peroxidase from Tomato Cultivated under Different Salinity ConditionsJOURNAL OF FOOD SCIENCE, Issue 1 2000J.N. Rodríguez-López ABSTRACT: By including hydrophobic chromatography in the purification scheme, 2 homogeneous tomato fruit peroxidase isoenzymes were obtained. The expression of these 2 peroxidases, one acid and the other basic, was determined in tomato fruits grown under different salinity conditions. Increased salinity modified the isoenzyme profile of tomato peroxidase. In tomatoes grown under highly saline conditions, there was an increase in the expression of the acid form with respect to the basic, the acid/basic ratio rising from 4.5 in tomatoes grown under normal saline conditions to 70 in those grown in highly saline conditions. Kinetic studies using 2,2,-azinobis(3-ethylbenzo-thiazolinesulfonic acid) as reducing substrate showed that increased salinity in the growth medium did not modify the kinetic parameter of tomato peroxidase over both hydrogen peroxide or reducing substrate. [source] The HOG pathway in the halophilic black yeast Hortaea werneckii: isolation of the HOG1 homolog gene and activation of HwHog1pFEMS MICROBIOLOGY LETTERS, Issue 2 2002Martina Turk Abstract The mitogen-activated protein kinase (MAPK) Hog1p plays an essential role in the yeast hyperosmotic response. A homolog of the HOG1 gene was isolated from the halophilic black yeast Hortaea werneckii encoding a putative 359 amino acid protein, HwHog1p, with high homology to Saccharomyces cerevisiae Hog1p and to other eukaryotic Hog1p homologs. HwHog1p contains a TGY motif within a protein kinase catalytic domain and a C-terminal common docking (CD) motif. Its activation by increased salinity is regulated at the posttranscriptional level. HwHog1p is located on the plasma membrane under nonstress conditions. Upon increased external salinity it is translocated from the membrane, presumably to the nucleus. [source] Germination of Salicornia bigelovii Ecotypes under Stressing Conditions of Temperature and Salinity and Ameliorative Effects of Plant Growth-promoting BacteriaJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2007E. O. Rueda-Puente Abstract Salinity is a major stress condition. Salicornia bigelovii is a valuable edible halophyte, considered to be a promising resource for cultivation in arid coastal zones. Its productivity depends on the supplementary provision of nitrogen, for which an option is chemical fertilization. Nevertheless, indiscriminate use of chemical fertilizers contributes to the problem of increased salinity. The inoculation of plant growth-promoting bacteria (PGPB) represents an alternative. Seed ecotypes from four coastal areas [Santa Rosa Chica, Santa Rosa Grande, Santa Cruz and Cerro Prieto (CP), Sonora, México] were collected, in order to inoculate them with two species of PGPB (Azospirillum halopraeferens and Klebsiella pneumoniae). Two germination tests were carried out to study the effect of salinity, temperature regime (night/day) and inoculation with PGPB on germination (percentage and rate), plant height, root length and biomass produced (fresh and dry matter). In the first test, all four ecotypes were considered, whereas in the second test only the CP ecotype was involved because it was found to be the outstanding ecotype in the previous test. Results showed inhibition of germination when salinity was higher in all ecotypes except CP. The CP ecotype showed a decrease of seed germination with an increase in NaCl concentrations at all temperatures tested. However, when it was inoculated with both PGPB, the germination percentage was influenced. [source] NITZSCHIA OVALIS (BACILLARIOPHYCEAE) MONO LAKE STRAIN ACCUMULATES 1,4/2,5 CYCLOHEXANETETROL IN RESPONSE TO INCREASED SALINITY,JOURNAL OF PHYCOLOGY, Issue 2 2009Fernando Garza-Sánchez The growth of microalgae in hypersaline conditions requires that cells accumulate osmoprotectants. In many instances, these are polyols. We isolated the diatom Nitzschia ovalis H. J. Arn. from the saline and alkaline water body Mono Lake (CA, USA). This isolate can grow in salinities ranging from 5 to 120 parts per thousand (ppt) of salt but normally at 90 ppt salinity. In this report, we identified the major polyol osmoprotectant as 1,4/2,5 cyclohexanetetrol by electron ionization-mass spectrometry (EI,MS), 1H, 13C nuclear magnetic resonance spectroscopy (NMR), and infrared (IR) and showed an increase in cellular concentration in response to rising salinity. This increase in the cyclitol concentration was evaluated by gas chromatography of the derived tetraacetylated cyclohexanetetrol obtaining an average of 0.7 fmol · cell,1 at 5 ppt and rising to 22.5 fmol · cell,1 at 120 ppt. The 1,4/2,5 cyclohexanetetrol was also detected in the red alga Porphyridium purpureum. Analysis of the free amino acid content in N. ovalis cultures exposed to changes in salinity showed that proline and lysine also accumulate with increased salinity, but the cellular concentration of these amino acids is about 10-fold lower than the concentration of 1,4/2,5 cyclohexanetetrol. The comparison of amino acid concentration per cell with cyclitol suggests that this polyol is important in compensating the cellular osmotic pressure due to increased salinity, but other physiological functions could also be considered. [source] Effect of salinity on carrying capacity of adult Nile tilapia Oreochromis niloticus L. in recirculating systemsAQUACULTURE RESEARCH, Issue 16 2006M A Kabir Chowdhury Abstract Effect of salinity on carrying capacity of a recirculation system for Nile tilapia, Oreochromis niloticus L.; production was assessed. Survival, growth and feed conversion ratio of adult Nile tilapia fed 30% crude protein diet for 88 days were measured at three different salinity levels (8, 15 and 25 g L,1) and two stocking densities (20 and 40 m,3) in three independent recirculating systems. Highest survival (98%) and a linear growth in net biomass (P<0.01) was observed in both densities at 8 g L,1 and in 20 m,3 treatment at 15 g L,1. Highest net biomass growth was observed in the 40 m,3 stocking density treatment at 8 g L,1 salinity level (P<0.05). Overall biomass growth was significantly affected by salinity indicating a decrease in Nile tilapia carrying capacity with increased salinity. About 11 000 kg ha,1 crop,1 of Nile tilapia can be obtained in recirculating systems at 8 g L,1 salinity, significantly higher than the net production at 15 g L,1 (5200 kg ha,1 crop,1) and 22 g L,1 (4425 kg ha,1 crop,1). [source] Sedimentation History of Neogene Lacustrine Sediments of Su,eo,ka Bela Stena Based on Geochemical Parameters (Valjevo-Mionica Basin, Serbia)ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2008AJNOVI, Aleksandra Abstract: Sediments of the western part of the Valjevo-Mionica basin (Serbia) were examined both geochemically and mineralogically to explain, on the basis of their sedimentological characteristics, the causes of changes in their qualitative and quantitative composition. A total of 62 samples obtained from the drillhole at depths up to 400 m was investigated. Using correlation of the obtained data, six geochemical zones were defined, two of which being specially distinguished by their mineralogical, geochemical and sedimentological characteristics. The first one, upper zone A, consists of banded marlstones interbedded with clay and oil shales and is characterized by presence of analcite and searlesite. These minerals and very high contents of Na2O indicate sedimentation in alkaline conditions with increased salinity in arid climate. That provided pronounced water stratification, as well as higher bioproductivity in the basin and sedimentary organic matter preservation. Therefore, the zone A sediments are characterized by high organic matter contents of the type which provides good potential for production of liquid hydrocarbons. Another specific zone, zone F, contains sediments with very high MgO, K2O and Li concentrations. Their geochemical correlation, as well as almost complete absence of illite in this zone, indicates the presence of interstratified clay mineral type illite-saponite (lithium-bearing Mg-smectite). [source] | |||||||||||||