The effect of increasing NaCl concentrations on biomass, hydrogen peroxide (H2O2), ascorbic acid (ASC), proline and total thiol, and the activity of some antioxidant enzymes in alfalfa (Medicago sativa L. cv. Gara-Yonjeh) were investigated. The dry weights of roots and shoots with increasing NaCl concentrations decreased progressively, and the strongest toxicity was detected at NaCl treatment of 200 mM. Superoxide dismutase (SOD) activity in the leaves increased gradually up to NaCl concentrations of 100, while the higher concentration of NaCl reduced SOD activity in both leaves and roots. The maximum levels of ascorbate peroxidase (APX) activity were increased at 150 mM and 100 mM NaCl in leaves and roots of Gara-Yonjeh, respectively. Peroxidase (POD) activity in roots of Gara-Yonjeh increased (82% at 200 mM) by salinity, while it decreased (43% at 200 mM) in leaves. In contrast, catalase (CAT) activitiy increased (84% at 200 mM) in leaves, and decreased (57% at 200 mM) in the roots of Gara-Yonjeh. Electrophoresis analysis suggested that different patterns in SOD, CAT and POD isoenzymes depend on NaCl concentrations, and the staining intensities of these isoforms are supported the results obtained from the spectrophotometric determinations. In POD and CAT, activity of isoform III was detected at all concentrations, by a “low-high-low” pattern, with the maximum activity at 50 mM of NaCl. Results imply that the function of antioxidant systems in higher NaCl concentration is responsible for the salt tolerance observed in Gara-Yonjeh.
Authors:S.-C. Ye, L.-Y. Hu, K.-D. Hu, Y.-H. Li, H. Yan, X.-Q. Zhang, and H. Zhang
Hydrogen sulfide (H2S) has been recently found to be a gaseous signaling molecule in plants. In this work, we studied the role of H2S in alleviating salinity stress during wheat grain germination (Triticum aestivum L. Yangmai 158). Pretreatment with NaHS, a H2S donor, during wheat grain imbibition, could significantly attenuate the inhibitory effect of salinity stress on wheat germination. NaHS-pretreated grain showed higher amylase and esterase activities than water control. NaHS pretreatment differentially stimulated the activities of catalase (CAT), guaiacol peroxidase (POD) and ascorbate peroxidase (APX), decreased the level of malondialdehyde (MDA) and reduced NaCl-induced changes in plasma membrane integrity in the radicle tips of seedlings compared with water control. We conclude that H2S plays an important role in protecting wheat grain from oxidative damage induced by salinity stress.
Authors:A. Joshi, K. Rejith Kumar, and H. Hinglajia
Highly significant temporal variations of salinity, Na
content were observed in the habitat. Although quantity of major amino acids was significantly different in leaves, stems and roots of
Rott. ex Willd., their concentrations did not reflect any temporal effects. Accumulation of sugars in vegetative organs and their fluctuations were not significant for thin leaved species
, but their content in
was affected by temporal changes. Amounts of Na
in plant organs were positively related with changes in salinity and mineral ion composition of the habitat. Two species remarkably differed in accumulating amino acids, sugars and mineral ions.
A simple method for the determination of trace concentrations of metals in saline water is described. The analytical procedure
involves the separation of metal ions of Cu, Zn, Hg and Fe by precipitation with diethyldithiocarbamate (DDTC). The radioisotope
X-ray fluorescence method using Si(Li) detector has been applied for the determination of metal ions closed in the DDTC deposition.
The aim of the study was to determine K-factors of homogeneous zones in
palm-groves in order to make possible the interpolation of these values to
other similar areas, and by this way to help the calculation of draining
parameters. Another goal was to interpret the agronomical aspects of the
results. Investigations for the determination of conductivity factors
(K-factors) were carried out in the palm-groves of the Oued Rhir Valley. The
measurements - conducted three times -
were made by the auger-hole method. After boring the hole, a perforated
cylinder was placed into it to prevent falling in. K-factor values were
calculated after van Beers. The mean of the three calculations was given as the
end result for the K-factors. Our results show that K-factor values are
influenced by the porosity, type, bulk density and texture of soils, their salt
content and the form of gypsum. The K-factor was extremely high in case of
sandy soils and soils containing crystallized gypsum. Water conductivity was
moderate in case gley and pseudogley were located in deeper layers. The lowest
values occurred when gypsum was found in cemented coherent particles.
Salinization in deeper layers influenced hydraulic conductivity only in case it
was associated with finer texture and airless layers. Besides date production, the traditional growing of
nitrogen-fixing perennial legumes (alfalfa, Egyptian clover, melilot, etc.) in
palm-groves is essential. Systemic
flooding irrigation decreases the salt content of soils, increases date and
legumes yields. Legumes - by their root-system - improve the nitrogen balance,
structure and water drainage of soils. The green parts of the cultivated
legumes serve as fodder for animals (goats, sheep, cows), which turn it to
manure. This manure increases the nutrient supply of the soils for palm-trees
and vegetables. The positive results of stubble and root manuring (green
manuring) of legumes is also confirmed by experiments on sandy soils. The
elaboration of a good plant rotation is possible. At last, date and vegetables
produced in this way could be sold better on the world market as bioproducts.
Authors:S. L. Krishnamurthy, S. K. Sharma, D. K. Sharma, P. C. Sharma, Y. P. Singh, V. K. Mishra, D. Burman, B. Maji, B. K. Bandyopadhyay, S. Mandal, S. K. Sarangi, R. K. Gautam, P. K. Singh, K. K. Manohara, B. C. Marandi, D. P. Singh, G. Padmavathi, P. B. Vanve, K. D. Patil, S. Thirumeni, O. P. Verma, A. H. Khan, S. Tiwari, M. Shakila, A. M. Ismail, G. B. Gregorio, and R. K. Singh
Genotype × environment (G × E) interaction effects are of special interest for identifying the most suitable genotypes with respect to target environments, representative locations and other specific stresses. Twenty-two advanced breeding lines contributed by the national partners of the Salinity Tolerance Breeding Network (STBN) along with four checks were evaluated across 12 different salt affected sites comprising five coastal saline and seven alkaline environments in India. The study was conducted to assess the G × E interaction and stability of advanced breeding lines for yield and yield components using additive main effects and multiplicative interaction (AMMI) model. In the AMMI1 biplot, there were two mega-environments (ME) includes ME-A as CARI, KARAIKAL, TRICHY and NDUAT with winning genotype CSR 2K 262; and ME-B as KARSO, LUCKN, KARSA, GOA, CRRI, DRR, BIHAR and PANVE with winning genotypes CSR 36. Genotypes CSR 2K 262, CSR 27, NDRK 11-4, NDRK 11-3, NDRK 11-2, CSR 2K 255 and PNL 1-1-1-6-7-1 were identified as specifically adapted to favorable locations. The stability and adaptability of AMMI indicated that the best yielding genotypes were CSR 2K 262 for both coastal saline and alkaline environments and CSR 36 for alkaline environment. CARI and PANVEL were found as the most discernible environments for genotypic performance because of the greatest GE interaction. The genotype CSR 36 is specifically adapted to coastal saline environments GOA, KARSO, DRR, CRRI and BIHAR and while genotype CSR 2K 262 adapted to alkaline environments LUCKN, NDUAT, TRICH and KARAI. Use of most adapted lines could be used directly as varieties. Using them as donors for wide or specific adaptability with selection in the target environment offers the best opportunity for widening the genetic base of coastal salinity and alkalinity stress tolerance and development of adapted genotypes. Highly stable genotypes can improve the rice productivity in salt-affected areas and ensure livelihood of the resource poor farming communities.
Authors:V. Kakade, A. Dubey, O. Awasthi, and A. Dahuja
Garcia-Sanchez, F., Carvajal, M., Sanchez-Pina, M. A., Martinez, V. (2000): Salinity resistance of Citrus seedlings in relation to hydraulic conductance, plasma membrane ATPase and anatomy of the roots. J. Plant Physiol. , 156 , 724
of starch in cotyledons Plant Growth Regulation 26 85 90
Leopold, A. C., Willing, R. D.: Evidence of toxicity effects of salt on membranes. In: Staples, R. C., Toeniessen, G. H. (eds), Salinity tolerance in plants
By using 188Re as a radiotracer, the extraction behavior of Re(VII) by a tertiary amine extractant N-235 from HCl and the back-extraction behavior of Re(VII) by HNO3 and ammonia were studied. A chemical separation procedure, which combined the acid alumina column and solvent extraction was established. The procedure was rapid and efficient for the separation of 186Re from 186W irradiated by 16 MeV deuterons. No-carrier-added 186ReO4– saline solution with high specific volume activity was obtained. The overall recovery yield of 186Re was about 85%.
Authors:K. Kondo, S. Ueda, Y. Chikuchi, H. Kawabata, N. Akata, H. Hasegawa, O. Mitamura, Y. Seike, and J. Inaba
Lake Obuchi is on the Shimokita Peninsula, Aomori Prefecture, Japan, near several nuclear fuel-related facilities. The lake
contains from oligohaline to polyhaline regions, and the salinity fluctuates greatly both spatially and temporally. This study
examined the possible effect of salinity on biological concentrations of 137Cs in phytoplankton on the basis of a culture experiment using stable Cs and phytoplankton species isolated from the lake.
In both Cyclotellaand Skeletonema, the biological concentrations of Cs varied with salinity conditions, and a positive linear relation was found between maximum
proliferation and biological concentrations of Cs.