The effect of water potential on accumulation of some essential elements in sugarbeet leaves, Beta vulgaris ssp. vulgaris

An investigation has been conducted on the effect of reduced water potential in nutrient solution on the accumulation of some essential macro- and micro nutrients in the aboveground pails of young sugarbeet plants. Plants of 8 different sugarbeet genotypes were exposed for 21 days to a nutrient solution whose water potential of 0.1 MPa was regulated by PEG. Contents of N, P, K Ca, Mg, Fe, Mn, Cu and Zn declined in all genotypes under water deficiency but the intensity of reduction varied among the genotypes. The results indicated that some harmful effects of water deficiency could be attributed to disturbances in plant mineral nutrition, especially the lack of N, P, and Mg, as well as to impaired ratios between the contents of particular elements, especially K/Ca

Bioenergetic aspects of competition between nitrogen metabolism and carbohydrate synthesis in small grains

Yields of small grains have been significantly increased in recent decades primarily by breeding. No corresponding progress has been made regarding protein content in the grain. That was mostly due to a negative correlation existing between yield level and protein content. Protein synthesis requires a much larger amount of energy that that required for carbohydrate synthesis. A hypothesis explains this negative correlation by competition for energy between nitrogen metabolism and carbohydrate synthesis. The proponents of this hypothesis surmise that nitrate reduction unfolds mostly at the expense of the energy released upon oxidation of carbohydrates and organic acids (heterotrophic), and not at the expense of light energy (autotrophic). In small grains, nitrate reduction takes place mostly in leaves, i. e., it is autotrophic. Under conditions of optimum nitrogen supply, protein content and yield per unit area increase but grain yield does not decrease although it could be expected if there existed a competition for energy between nitrogen metabolism and carbohydrate synthesis. Protein content reduction in consequence to yield increase could be explained by the dilution effect, as evidenced by similar reductions of other substances in the grain, for example mineral elements. When considering the competition for energy between nitrogen metabolism and carbohydrate synthesis, it should not be overlooked that nitrogen stimulates the energy transport in plants indirectly, by stimulating the photosynthetic activity and thus the utilization of light energy by plants

Effects of Mo, Zn, Sr and Ba loads on these elements' uptake and oil content and fatty acid composition of rapeseed

Studied in the present paper were the long-term effects of the application of high Mo, Zn, Sr and Ba rates (0, 90, 270, and 810 kg ha-1 on rapeseed oil content and oil fatty acid composition. The trace elements were applied in the spring of 1991, while the rapeseed was sown on a calcareous сhernozem soil in 2001. The trace elements differed significantly in their rates of accumulation in rapeseed plants. Relative to the control, the Mo content of the stem increased up to 1,000 times, that of the chaff over 100 times, and that of the seed around 60 times. The levels of the other trace elements increased considerably less relative to the control. The increases were typically twofold to threefold, depending on the plant part involved. The trace elements accumulated the most in the vegetative plant parts, except for Zn, a major quantity of which was found in the seed as well. The application of the high rates of Sr, Zn and, to an extent. Mo reduced the seed oil content of rapeseed. However, the differences were not statistically significant. The application of the trace elements had no significant effect on the fatty acid composition of the rapeseed oil, either. The increased levels of the trace elements found in the rapeseed plants indicate that 11 years after application significant amounts of the applied elements are still present in the soil in a form available to plants. However, the rates were not high enough to affect the synthesis of oil and its fatty acid composition

Effect of lead contamination of maize seed on its biological properties

Effect of treatment of seed with various lead concentrations (0, 10-5, 10-4, 10-3, and 10-2 mol/dm3) on accumulation and distribution of lead (Pb) in seedling, seed germination, seedling growth, and mobilization of mineral matter during seed germination was investigated. Content of Pb in the root and the shoot indicates that seeds imbibed in solutions of various Pb concentrations took up Pb intensively. Content of Pb in the root and the shoot increased with increase of Pb concentration and it was much larger in the root than in the shoot. Contrary to this, the accumulation coefficient was greater in the shoot than in the root. Treatment of seed with Pb did not significantly affect its biological properties. Increase of Pb concentration decreased germination ability, germination energy, and percentage of typical seedlings, while increasing the number of atypical seedlings and non-germinated seeds. Contamination of seed by Pb did not affect the dry matter mass and the growth of young plants shoots, while the length of the primary root, the mesocotyl root as well as the root mass at the highest Pb concentration, significantly decreased. Translocation of mobilized mineral matter from the seed during germination and growth of young plants into the root and shoot was specific, depending on elements. Only the implementation of the highest implemented Pb concentration affected mobilization and translocation of some elements. Based on the obtained results, it can be concluded that maize is characterized by significant tolerance to Pb contamination during seed germination and growth of seedlings

Seed protein variability in safflower

Total seed proteins in two safflower species (Carthamus tinctorius L. and C. lanatus L) have been separated by the SDS-PAGE method. Their molecular masses ranged from 120 to 20 kDa. All C. tinctorius genotypes under study exhibited identical electrophoretic patterns which differed from the pattern exhibited by the wild species C. lanatus in the number and position of protein bands. Differences in protein profiles occurred in regions around 60 kDa, from 43 to 36 kDa and around 30 kDa. Statistically significant differences in seed protein content were found among safflower genotypes from different countries as well as among genotypes from the same country but from different sites. The highest seed protein content was found in a genotype originating from the USA

The concentration ratio of alkaline earth elements calcium, barium and strontium in grains of diploid, tetraploid and hexaploid wheat

Even though calcium (Ca), strontium (Sr) and barium (Ba) belong to the same group of the periodic table of elements, and thus have similar chemical features, their importance for plants differs greatly. Since plants do not have the ability to completely dis­criminate between essential (e.g. Ca) and non-essential elements (e.g. Sr and Ba), they read­ily take all of them up from soil solution, which is reflected in the ratios of concentrations of those elements in plant tissues, and it influences their nutritive characteristics. The ability of plant species and genotypes to take up and accumulate chemical elements in their different tissues is related to their genetic background. However, differences in chemical composition are the least reflected in their reproductive parts. Hence, the aim of this study was to evaluate ratios of concentrations of Ca, Sr and Ba in the whole grain of diploid and tetraploid wheat - ancestors of common wheat, as well as in hexaploid commercial cultivars, grown in the field, at the same location, over a period of three years. The investigated genotypes accumulated Ca, Sr and Ba at different levels, which is reflected in the ratio of their concentrations in the grain. The lowest ratio was established between Ba and Sr, followed by Ca and Ba, while the highest ratio was between Ca and Sr. Moreover, the results have shown that the year of study, genotype and the combination highly significantly affected the ratio of the concentration Ca:Sr, Ca:Ba, and Ba:Sr