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Notes: The effect of replacing 50% or 95% of the potassium by sodium on growth and on potassium and sodium levels in three genotypes of sugar beet (MONOHILL; ADA; FIA) has been studied in water culture over a period from 2 to 9 weeks.In all three genotypes there was a preferential uptake of potassium compared to sodium. Nevertheless, at high sodium supply most of the potassium was replaced by sodium, particularly in the leaves. At the same supply the accumulation of sodium in the leaves increased in the following order: ADA 〈 MONOHILL 〈 FIA. Even with high dominance of sodium in the medium, the youngest leaves of FIA held about 0.5 mmol potassium per g dry matter, and potassium was evidently translocated from old leaves to the new growth.Effects of sodium on growth became more important with time. After 9 weeks, 50% replacement of potassium by sodium increased growth of all plant organs of the three genotypes. Replacing 95% of potassium by sodium depressed growth of the storage root in MONOHILL and particularly in ADA, with simultaneous enhancement of leaf growth in the latter. In FIA, however, this treatment further stimulated both leaf and, particularly, storage root growth. Sodium in comparison with potassium increased the sucrose concentration in leaves and storage roots. The highest sucrose concentration in the storage roots of ADA and FIA was obtained in the treatment with 95% sodium.The results demonstrate pronounced genotypic differences in sugar beet with respect to the response to sodium. FIA has the most natrophilic behaviour and might be a promising genotype for breeding programmes for adaptation of sugar beet plants to soils high in sodium.

Notes: The effects of NaCl and replacement of K+ by Na+ on the lipid composition of the two sugar beet inbred lines FIA and ADA were studied (a) with increasing additions of NaCl to the basal medium, and (b) with increasing replacement of K+ by Na+ at the same total concentration as in the basal medium. Direct relations were noted between NaCl concentration of the nutrient solution and the phospholipid concentration in the roots of FIA, the genotype characterized by a low K+/Na+ ratio, as well as between NaCl in the medium and the phospholipid concentration in the shoots of ADA, the genotype with a high K +/Na + ratio. The sulfolipid level in the roots of FIA was maintained at higher NaCl concentrations, while it was decreased in ADA. The glycolipid concentration in the shoots of ADA and the degree of unsaturation of the fatty acids of the total lipid fraction were decreased by salinity, indicating reduced biosynthesis of chloroplast glycolipids and/or accelerated oxidation of these lipids in the presence of NaCl.In the Na+ for K+ replacement experiment a low content of K+ in the medium resulted in decreased levels of total lipids, phospholipids and sulfolipid in the roots of both genotypes, which did not relate to root growth. K+-leakage from the roots at low K+-level in the medium may be reduced by the increase in saturation of the lipids. In the shoots of ADA increased levels of total lipids, phospholipids and Sulfolipid were noted at a low K+-concentration of the nutrient solution.

Notes: A microsomal fraction (10,000–30.000 g) was prepared from roots of Cucumis satirus L. (cv. Bestseller Fl) grown in solution culture. The ATPase activity was stimulated by Mg and Mn with optima between pH 6 and 7. Stimulation by Ca was obtained only above pH 7. Activations by Mg and Mn were inhibited by Ca, Mn and Mg interacted, so that Mn appeared strongly inhibitory for activation by Mg and Mg weakly inhibitory for activation by Mn: the simplest interpretation for this would be two separate enzymes. Cucumber accumulates and deposits Ca contrary to wheat and oat, which contain Ca-activated ATPase in the pH region 6 to 7. The Ca data for cucumber are compared with earlier findings from wheat and oat and are tentatively related to known physiological differences.

Notes: Field grown leaves of sugar beet contained 0.89% of their fresh weight as chloroform : methanol 1 :2 extractable material, whereas climate chamber grown material contained 0.34, 0.15, and 0.16% in leaves, stalks, and roots respectively. A striking feature was the high proportion of sulfolipid: 7% of the total extractable of the field grown leaves, 19.5, 28.0, and 37.0% of the total extractable of respectively leaves, stalks, and roots from the climate chamber grown material. Among the fatty acids, all chain lengths from C12 to C28 were found, except only C17 and C19—Exceptionally high contents of fatty acids with a chain length of C26 or C28 were noted in some cases.The 2500–20,000 g fraction of root homogenates contained 19% of the total root lipids. Almost all of the phosphatidyl choline and about half of the phosphatidyl ethanolamine, but only 5% of the sulfolipid followed the fraction. A fractionation of conjugate lipid types was evident, with a loss of 18/2 and 18/3 conjugates, and with an increase in the proportions of 16/0 and, possibly, of the long-chain (around C26) conjugates.The unspecific ATPase activity of the 2500–20,000 g fraction was rendered specific for (Na++ K+) stimulation by treatment with 0.1% deoxycholate for 1 hour. This induced a more than 2-fold swelling of the preparation. About half of its total lipids were lost. Again, this loss was a fractional one, so that the phosphatidyl choline lost its long-chain (about C26) fatty acid conjugate while the short to medium length chain conjugates remained; whereas the reverse was the case with the sulfolipid.The ATPase activity of the 2500–20,000 g fraction was destroyed by a 24 hour treatment with deoxycholate. As compared with the 1 hour treatment, the preparation lost about 20% both of its volume and of its chloroform : methanol extractable material. The quantitatively dominating loss was found in the (pigment + neutral fat) fraction. The monogalactosyl diglyceride, the phosphatidyl inositol, and a strongly acidic unknown fraction survived the deoxycholate treatments comparatively well. In the sulfolipid the fractionating effect of the prolonged deoxycholate treatment expressed itself as a loss mainly from the long-chain (about C26) fatty acid conjugate.The (Na++ K+) stimulation of the ATPase function of the particulate preparation is thus correlated with the balance between the long-chain (about C26) fatty acid conjugates of zwitterionic phosphatidyl choline and anionic sulfolipid. This is of theoretical interest, since it indicates that the specific lipid composition under appropriate conditions may influence the charge and conformation of a lipoprotein complex, thereby determining its functional capacities.

Notes: Treatment of Nicotiana glutinosa L. cell suspension cultures with chitosan results in the co-induction of phenylalanine ammonia lyase, 4-eoumarate:CoA ligase, tyrosine decarboxylase and tyramine hydroxycinnamoyltransferase, all involved in the biosynthesis of hydroxycinnamoyltyramines. The highest enzyme activities were observed around 12 h after addition of 0.8 to 1 mg chitosan per g fresh weight of cells. No hydroxycinnamoyltyramines could be detected by TLC or HPLC of extracts made from non-treated or elicited cells. [14C]-Tyramine was incorporated into insoluble polymeric material at a higher rate in elicitor-treated than in non-treated cells of N. glutinosa. Tyramine hydroxycinnamoyltransferase could be induced in suspension cultured cells of Eschscholtzia califortnca Cham, but not in cells of Phaseolus vulgaris L. or Catharanthus roseus (L.) G. Don by addition of a yeast elicitor to the growth medium.

Notes: Lipid composition of whole roots of wheat (Triticum vulgare Vill. cv. Svenno Spring Wheat) and oat (Avena sativa L. cv. Brighton) and of cell wall fractions, mitochondrial fractions and microsomal fractions of these roots were studied. Lipid composition depended upon the level of mineral nutrition. In wheat total phospholipids, phosphatidyl choline and sulfolipid content was highest in the roots grown at the higher salt concentration, while the reverse was true for oat roots. In both species glycolipid and sterol content was lower in the high salt roots, at the same time as higher proportions of them were built into the microsomal fraction. Phosphatidyl choline content of the wheat root membrane fractions increased with the salt level, while the opposite occurred in the oat roots.The phosphatidyl choline content may be correlated with the (Ca2+, Mg2+)-stimulated ATPase activity.