The ef.ects of.three nitrogen sources (ammonium, nitrate and ammonium+nitrate) and three salt treatments (0, 100 and 200 mM NaCl) on nitrate reductase activity, proline, soluble protein and carbohydrate contents ...
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The ef.ects of.three nitrogen sources (ammonium, nitrate and ammonium+nitrate) and three salt treatments (0, 100 and 200 mM NaCl) on nitrate reductase activity, proline, soluble protein and carbohydrate contents in psylliom (Plantago ovata) plants were Studied. The nitrate reductase activity tended to increase when NO3- was included in the root-zone solution, but decrease as salinity increased. All N sources stimulated plant growth and nutrient uptake. Shoot and root dry matter tended to decrease as salinity increased, but less so when both NH4+ and NO3- were present. Shoot biomass accumulated to signif.cantly greater quantities under the mixed-N treatments than when produced using either NH4+ or NO3- N-f.rm alone. Although not statistically signif.cant, the root biomasses showed a similar tendency. Generally, leaf.proline and soluble shoot carbohydrate contents increased with increasing salinity in contrast to soluble protein which decreased regardless of.the N source. Under salinity conditions, the concentration of.Na+ in shoot and root tissues was highest in ammonium-N treatment, while that of.K+ was highest in the mixed-N treatment.
Some years ago, we published a new species of.Pelvetia, namely, P. siliquosa and brief.y discussed its distribution. This species was reported f.om the eastern coast of.the Shantung Peninsula, f.om Dairen on the Liaot...
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Some years ago, we published a new species of.Pelvetia, namely, P. siliquosa and brief.y discussed its distribution. This species was reported f.om the eastern coast of.the Shantung Peninsula, f.om Dairen on the Liaotung Peninsula and f.om South Huangcheng Island of.the Miaotao Islands at the Strait of.Pohai. Since 1953, more data on the distribution of.this plant have been accumulated, showing its much wider distribution than we f.rst thought. According to the new data, at the Shantung
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