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The contents of Na, K, CI, chlorophyll and the foliar ultrastructure of rice seedlings grown in NaCl solution at various concentrations were investigated under light and dark conditions. The seedlings were first grown in water for 7 d under a light condition and then in NaCl solutions at various concentrations for 24 h under a light or dark condition. The Na and CI contents in the 3rd leaves increased as the concentration of NaCl in the culture solution increased, and were significantly higher under a light condition than under a dark condition. The K content was scarcely influenced by the NaCl concentration under both conditions. The chlorophyll content in the 3rd leaves of the seedlings decreased as the NaCl concentrations of the culture solution increased under a light condition but not under a dark condition. In the 3rd leaves of the seedlings grown in the NaCl solution under a light condition, the thylakoids of chloroplasts in mesophyll cells were swollen and showed a wavy configuration. Under a dark condition, however, the thylakoids appeared intact under saline conditions although the leaves accumulated a large amount of Na and CI than in a light condition. The present study suggests that the damages in the chloroplasts, such as a decrease in the chlorophyll content and the degradation of thylakoids, were caused by a light-dependent reaction and not directly by accumulation of excess salt.

Segments of rice leaves at different nodal positions were incubated in NaCl solutions for various periods, and the chlorophyll content, Na content, CI content, Na/K ratio and the ultrastructure of excised leaf tissues were examined. The chlorophyll content of the leaf tissues decreased with increasing NaCl concentration and incubation period. Na and CI contents of the leaf tissues also increased with increasing NaCl concentration, but the decrease in chlorophyll content by salt stress was greater in old than in young tissues even when both tissues contained comparable amounts of Na and CI. The presence of benzylaminopurine (BAP) alleviated the salt stress-induced decrease in chlorophyll content, but did not significantly affect the element contents. Ultrastructural damages were apparent in the chloroplasts of the leaf tissues subjected to salt stress. In 0.1% NaCl-treated old leaf tissues, the thylakoids were swollen, the envelope was partly destroyed causing leakage of the chloroplast contents. However, these damages were alleviated by the addition of BAP to the NaCl solution. In young leaf tissues, the thylakoids were swollen by incubation in 1.0% NaCl solution, but no structural distortion was observed in a 0.1% NaCl solution even without BAP added. The present study suggests that the leaf tissues were damaged by an increasing salt content and became more sensitive to salt stress with advancing leaf age. BAP seemed to alleviate the damages by salt stress through retardation of leaf aging.

The distributions of Na and chlorophyll in the leaves of rice (Oryza sativa L.) seedlings grown under a saline condition were examined in relation to the anatomical changes caused by salinity. In salt-treated plants, the Na content was higher in older leaves and basal part of the leaf. In the 4th leaf of salt-treated plants, Na content was the highest in the middle part of the leaf sheath and decreased toward the tip of the leaf blade. The chlorophyll content in the 4th leaf was decreased by salt treatment at the tip and middle parts of the leaf blade, whereas it was unaffected in the leaf sheath and at the base of the leaf blade. Electron microscopic studies revealed that salt-treatment caused plasmolysis, vesiculation of cellular membranes and degradation of cytoplasm at the tip of the leaf blade, but scarcely caused such alterations at the base of the leaf blade. The present study suggests that the damage by salinity correlates more strongly with the age of the tissue than the Na content of the tissue.

Abstract: The objective of this work is to study the influence of Na on the properties of Cu(In,Ga)Se2 (CIGS) absorber layers and finished solar cell devices on polyimide substrates. For this study Na is added to 3-stage grown CIGS thin films by evaporation of a NaF precursor layer prior to the absorber deposition. The precursor layer modifies the CIGS growth kinetics. A stronger Ga-gradient and a decrease of grain size are observed when the Na content increases. An increase in V oc for a higher Na concentration at a nominal growth temperature of T sub,max =500 °C during CIGS deposition is explained by a higher carrier density, as obtained by DLCP measurements. The higher carrier concentration for the higher Na content could be attributed to the reduction of a compensating donor. However, a low J sc does not allow for an enhanced efficiency possibly due to a shorter depletion region, as observed by admittance spectroscopy, and effective diffusion length. [Copyright &y& Elsevier]

Synthetic reaction of aluminum isopropoxide, which is used as a starting material for catalytic-grade alumina, has been studied in the presence of a small amount of HgI2, HgCl2, I2 or FeCl3 from aluminum dross. It was synthesized by solid-liquid reaction between the aluminum metal and isopropyl alcohol, using vacuum distillation process. The purity of the synthesized aluminum isopropoxide was obtained over 97.6% experimentally, which had been analyzed quantitatively by complexometric method. The initial amount of sodium, which directly affects the catalytic activation in the alumina catalyst, was in the range of 0.926 to 1.563 wt% in the aluminum dross. Finally, it was decreased to 0.007 wt% in the aluminum isopropoxide product. Yield was changed according to the amount of aluminium existing in the aluminum dross. Aluminum could mostly be recovered regardless of the amount of aluminium existing in the aluminum dross. [ABSTRACT FROM AUTHOR]

Changes in the K, Na and P content of solution‐grown and soil‐grown winter wheat (Triticum aestivum L. cv. Martonvásári 8) were followed during the life cycle. In parallel experiments the influx of K+(86Rb) and H232PO‐4 and the translocation of these ions to the shoot were also measured. The K content increased during the seedling and tillering stages (autumn and winter period), but then decreased rapidly as the temperature rose. The influx and translocation of K+ increased during vegetative growth and declined in the generative phase. Na+ replaced K+ when K+ uptake was limited. The P content changed less than the K content, but influx was maximal during elongation. Both influx and translocation slowed greatly in the grain‐filling period. For both minerals the ratio of influx to net uptake was estimated for the life cycle. This ratio was high for the soil‐grown plants but low for the solution‐grown plants, suggesting that the supply of K and P was limiting the growth of the former but not of the latter plants. It is suggested that the transport of K and P during the life cycle is regulated by metabolism‐dependent direct routes (i.e. negative feedback mechanisms) during vegetative growth and by passive, indirect routes in the generative stage. The possibility of hormone‐directed transport processes is also discussed. [ABSTRACT FROM AUTHOR]

Some of the measures suggested for amelioration of drought effects include application of N fertilizer and plant growth regulators (PGRs). Since N-fixing bacteria produce plant growth substances (PGRs), the effect of foliar application of an active strain of Klebsiella sp. (KUPOS) on IR-50 rice was examined using three foliar sprays applied at 10-day intervals. Irrigation once every 3 days was essential for plant growth. Application of KUPOS and 40 kg N ha improved grain yield of acutely water stressed plants from 330 kg ha to more than 1300 kg ha along with an improvement in several growth variables and yield determinants. Indole acetic acid, kinetin and GA, in a mixture of 10 M of each, were less effective than KUPOS in alleviating stress effects. The adverse effects of water stress on respiration and photosynthesis as indicated by CO exchange were also alleviated by these treatments. While uptake of K, Mg, Ca, Fe and Mo was increased, Na content decreased, accompanied by an increase in proline content. The order of effectiveness of the treatments was 40 kg N ha >KUPOS>PGRs. [ABSTRACT FROM AUTHOR]

• Most ecotypes germinated even in severe salinities but germination speed decreased. • Carotenoid content increased but chlorophyll content decreased by salinity. • Electrolyte leakage was higher in low yielding ecotype. • Shoot and root Na content negatively correlated with grain and biomass. • Higher activities of anti-oxidant enzymes did not correlate with salt tolerance. Rocket (Eruca sativa L.) is an old native plant well adapted to diverse climates in Iran. It's known for the ability to grow and produce seeds rich in protein and oil as well as edible foliage under marginal conditions and has a potential as a promising oil seed. Nonetheless, little is known about its response to salt stress. This study aimed to evaluate possible genetic diversity of local landraces of rocket in terms of salinity tolerance both in germination and whole plant level. In the first experiment, germination characteristics of seven ecotypes of rocket named based on the region of collection as Sirjan, Bardsir, Rigan, Shahdad, Abadeh, Lamerd and Darejove were assayed under increasing salinity from 0 to 18 dS/m. Increasing salinity decreased all germination indices but ecotypes significantly differ in the magnitude of response. Averaged over salinity levels and based on scoring values for final germination percentage, germination rate and seed vigor, one superior (Sirjan), one inferior (Bardsir) and one moderate (Darejove) ecotype were selected for further investigation in the second experiment in which plants were subjected to three salinity levels (1.8, 6 and 12 dS/m) in a hydroculture system and some of their biochemical, physiological and dry matter accumulation attributes were evaluated. Results showed that increasing salinity decreased grain and biological yield, relative water content, leaf chlorophyll content and leaf area but increased leaf carotenoids content, electrolyte leakage, proline and soluble sugars concentrations and shoot and root Na content. Also, in all three ecotypes activities of catalase, superoxide dismutase, guaiacole peroxidase and ascorbate peroxides increased in response to application of 6 or 12 dS/m salinity, but these alterations were not correlated with dry matter or grain production. Na shoot content, however, was closely and negatively associated with grain and biological yield and differ significantly among ecotypes. Interestingly, Bardsir, the least salt tolerant ecotype at germination, was the best in hydroculture experiment and often showed the highest values for the most growth parameters measured. These differential responses suggest a possible change in salt tolerance mechanism along with developmental stages transition. [ABSTRACT FROM AUTHOR]