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The purpose of undertaken investigation was to test the possibility of decreasing nickel toxic influence on florescence and fructification of tomato (Lycopersicon esculentum Mill.) 'Koralik' cv. and cucumber (Cucumis sativus L.) 'Hermes F1' cv. plants by introducing into contaminated medium the ion exchange substrate BIONA 312 - ion exchange resin possessing sorptive properties and containing nutrient elements. In experiment, two levels of nickel (NiSO4·7H2O), i.e. 40 or 100 mg Ni·kg-1 of the substrate, as well as two doses of the ion exchange substrate BIONA 312 ie. 20 or 50 g·kg-1 of the substrate (relatively 2 and 5% of medium weight), were applied. As a substrate hortisol and quartz sand at rate 2:1 was used. Nickel significantly influenced florescence and fructification date of experimental plants. Nickel at dose 40 mg Ni·kg-1 of the substrate caused earlier florescence and earlier setting of tomato fruits, as well as significant decrease in the number of cucumber female flowers. Late and limited blooming of tomato plants growing in the medium contained 100 mg Ni·kg-1 of the substrate resulted in not ripping fruits till the ened of experiment. Under these circumstances, during florescence a complete lack of cucumber female and male flowers was recorded that resulted in complete lack of fruit crop. Ion exchange substrate BIONA 312 introduced to the contaminated medium decreased toxic influence of nickel on the experimental plant species significantly increasing flowers and fruits number. Irrespective of the nickel dose introduced to the medium more efficent for the reduction of this metal phytotoxicity turned out to be addition of ion exchange substrate BIONA 312 at the dosage 5 than 2%. Moreover after introducing 2 or 5% ion exchange substrate dose tomato plants groving in the medium containing 40 mg Ni·kg-1 earlier and more intensive florescence as well as eariel fruits ripeness were observed.
The author studied the effect of different nickel concentrations (0, 0.4, 40 and 80 μM Ni) on the nitrate reductase (NR) activity of New Zealand spinach (Tetragonia expansa Murr.) and lettuce (Lactuca sativa L. cv. Justyna) plants supplied with different nitrogen forms (NO3⁻–N, NH4⁺–N, NH4NO3). A low concentration of Ni (0.4 μM) did not cause statistically significant changes of the nitrate reductase activity in lettuce plants supplied with nitrate nitrogen (NO3⁻–N) or mixed (NH4NO3) nitrogen form, but in New Zealand spinach leaves the enzyme activity decreased and increased, respectively. The introduction of 0.4 μM Ni in the medium containing ammonium ions as a sole source of nitrogen resulted in significantly increased NR activity in lettuce roots, and did not cause statistically significant changes of the enzyme activity in New Zealand spinach plants. At a high nickel level (Ni 40 or 80 μM), a significant decrease in the NR activity was observed in New Zealand spinach plants treated with nitrate or mixed nitrogen form, but it was much more marked in leaves than in roots. An exception was lack of significant changes of the enzyme activity in spinach leaves when plants were treated with 40 μM Ni and supplied with mixed nitrogen form, which resulted in the stronger reduction of the enzyme activity in roots than in leaves. The statistically significant drop in the NR activity was recorded in the aboveground parts of nickel-stressed lettuce plants supplied with NO3⁻–N or NH4NO3. At the same time, there were no statistically significant changes recorded in lettuce roots, except for the drop of the enzyme activity in the roots of NO3⁻-fed plants grown in the nutrient solution containing 80 μM Ni. An addition of high nickel doses to the nutrient solution contained ammonium nitrogen (NH4⁺–N) did not affect the NR activity in New Zealand spinach plants and caused a high increase of this enzyme in lettuce organs, especially in roots. It should be stressed that, independently of nickel dose in New Zealand spinach plants supplied with ammonium form, NR activity in roots was dramatically higher than that in leaves. Moreover, in New Zealand spinach plants treated with NH4⁺–N the enzyme activity in roots was even higher than in those supplied with NO3⁻–N.
The sensitivity of six vegetable plants on nickel at early stages of their growth was investigated by index of tolerance. Besides the possibility of nickel fitostabilization by additional application of iron or calcium was tested. The experiment was conducted on Petri dishes. Different concentrations of nickel (O; 0,03; 0,06mM Ni as sulphate), iron (0,05; O,OlmM Fe as Fe2+ citrate) and calcium (0,50; 0,75; 1mM calcium carbonate) were added. Taking into consideration the sensitivity, investigated vegetables can be ordered in the following way: Cucurbita pepo conv. giroL.>Lactuca sativa L.>Sinapis alba L.>Spinacia oleracea L. = Zea mays var.saccharata Kcke.>Phaseolus vulgaris L. Positive, statistically significant effect of nickel fitostabilization (0,03 or 0,06mM Ni) on elongative growth by the iron application Fe) was shown for Zea mays var. saccharata Kcke independent1y of Ni .,tion in the nutrient medium as well as for Sinapis alba L. and Phaseolus ,L. in 0,06mM Ni. Addition as much as 0,75mM Ca in the presence 0,03mM , psitive result on Sinapis alba L and Phaseolus vulgaris L. seedlings as well as ,ys var. saccharata Kcke and Lactuca sativa L. roots and Cucurbita pepo i,romontiina L. shoots. Addition of 0,75mM Ca in the presence 0,06mM Ni elongative growth of Zea mays var. saccharata Kcke seedlings. Application resulted in the promotion of elongative growth of Zea mays var. saccharata (0,03mM Ni) as well as Spinacia oleracea L. roots (0,06mM Ni).
The objective of the studies undertaken was to assess the possibility of ion exchange substrate BIONA 312 use for nickel bioavailability limitation in cucumber (Cucumis sativus L.) 'Hermes' cv. as determined on the ground of chlorophyll and Ni content. BIONA 312, regarding the chemical composition, is a mixture of strongly acid cation exchanger KU-2x8 and polyfunctional weakly alkaline anion exchanger EDE-10P. The experiment was differentiated in regard to nickel and ion exchanger content. The following doses of Ni (in the form of NiSO₄ ) were introduced: 0, 30 or 75mg Ni·dm⁻³ of the substrate. BIONA 312 was added to the medium in the following doses: 0, 2 or 5% of substrate volume. Together with Ni dose increase in the medium there was recorded a significant increase of this metal concentration in the cucumber biomass. Nickel in the amount 30 mg·dm⁻³ did not affect considerably the changes in any of chlorophyll form, but a dose 75mg Ni·dm⁻³ has caused a significant decrease in chlorophyll ,,a” concentration in cucumber leaves. Simultaneously with the increase in the nickel content in the nutritive environment the decrease in the value of organic mass productivity coefficient was observed. The introduction of 5% ion exchange substrate BIONA 312 into the medium containing nickel in the amount 30 or 75 mg·dm⁻³ induced a significant growth of the studied chlorophyll fractions in the cucumber leaves. BIONA 312 introduced to the environment contaminated with nickel in the amount of 30 or 75 mg·dm⁻³ has significantly reduced Ni content in the cucumber biomass simultaneously increasing participation of roots in organic mass production. More efficient for the reduction of harmful Ni effect on the cucumber plants turned out to be introduction of ionite sorbent BIONA 312 at the dosage 5% than 2%.
W pracy określono zmiany zawartości cukrów redukujących w roślinach słonecznika (Helianthus annuus L.) zależnie od stężenia i drogi wnikania niklu. Dodatkowo w organach asymilacyjnych oznaczano zawartość chlorofilu, a w korzeniach, łodygach i liściach zawartość niklu. Doświadczenie przeprowadzono metodą kultur wodnych na pożywce Hoaglanda. Eksperyment zróżnicowano pod względem dawki oraz drogi wnikania (przez korzeń lub liść) niklu, podanego w formie NiSO₄·7 H₂O. Dokorzeniowo nikiel wprowadzono w stężeniach: 0, 35, 100 lub 200 µmol·dm⁻³. Aplikację dolistną wykonano opryskując rośliny 10 cm³ roztworu siarczanu niklu o stężeniu 5 lub 10 µmol·dm⁻³. Rośliny kontrolne opryskano 10 cm³ wody destylowanej. Uzyskane wyniki wskazują, że zawartość niklu w korzeniach, łodygach i liściach słonecznika, niezależnie od drogi wnikania, istotnie wzrastała wraz ze wzrostem aplikowanej dawki tego metalu i na ogół była skorelowana ze wzrostem zawartości węglowodanów redukujących w liściach oraz spadkiem koncentracji tych związków organicznych w łodygach i korzeniach, jak również chlorofilu w organach asymilacyjnych.
Celem badań było określenie wpływu wysokiego poziomu Ni w podłożu na zawartość Fe w roślinach bobu odmiany Windsor Biały. Doświadczenie wegetacyjne przeprowadzono w wazonach w warunkach kontrolnych. Podczas wegetacji roślin wilgotność podłoża utrzymywano na poziomie około 60% pełnej pojemności wodnej przy pH 4.5. Doświadczenie zlikwidowano w początkowym okresie kwitnienia roślin bobu w serii kontrolnej. W suchym materiale części nadziemnych i korzeni oznaczono zawartość żelaza i niklu metodą spektrofotometrii atomowej ASA. Analiza wyników oznaczeń chemicznych pozwala wnioskować, że na zawartość żelaza w częściach nadziemnych i korzeniach wyraźnie wpływa poziom niklu w podłożu. Spadek koncentracji Fe szczególnie w częściach nadziemnych był skorelowany z wysoką dawką Ni. Ponadto wykazane zróżnicowane gromadzenie Ni w poszczególnych organach rośliny było uzależnione od zasobności podłoża w ten pierwiastek.
The purpose of this paper was to determine the sunflower (Helianthus annuus L.) reaction to nickel depending on the metal concentration and penetration way, i.e. through roots or leaves. Nickel was introduced into the nutritional solution (intraroot application) at amounts: 0 (control), 35, 100 or 200 μM, while intraleaf application was performed by spraying plants with water (control) or nickel containing solution at the concentration of 5 or 10 μM. Plants treated with nickel intraroot than intraleaf were characterized by a considerably higher metal content in roots and lower in leaves. Independently of the penetration way increasing metal concentrations caused a significant decrease of the parameters of physiological root activity, i.e. the root volume, total and active adsorption surface and 1 cm³ root active surface, in that a greater decrease of the root parameters was shown on intraroot than intraleaf application of the metal. Environment contamination with nickel caused also a chlorophyll concentration decrease in leaves, in that intraleaf nickel application, in contrast to intraroot, resulted in a higher decrease of chlorophyll b than a. Older than younger leaves showed a higher susceptibility to nickel applied intraroot, whereas roots were resistant to nickel applied intraleaf. The content of S-SO₄ in the sunflower depended on the nickel concentration and penetration way – intraleaf nickel application caused significant S-SO₄ increase in leaves and roots, whereas intraroot application resulted in S-SO₄ content increase especially in roots.
W prezentowanej pracy podjęto próbę określenia wpływu zasolenia gleby jonami Na⁺ i Cl⁻ na walory dekoracyjne żeniszka meksykańskiego (Ageratum houstonianum MILL.) oraz możliwość neutralizacji skutków zasolenia poprzez wprowadzenie do podłoża sorbentu jonitowego BIONA 111, jako resorbentu jonów zasalających. Doświadczenie przeprowadzono metodą kultur stałych w wazonach o pojemności 1 dm³. Eksperyment zróżnicowano pod względem zasolenia podłoża i zawartości sorbentu jonitowego. Zasolenie podłoża wynosiło 0 lub 2,83 mS·cm⁻¹. Bionę wprowadzono w ilości 0 lub 3% całej objętości wazonu. Żeniszek meksykański okazał się gatunkiem mało tolerancyjnym na zasolenie odpowiadające przewodności elektrycznej równej 2,83 mS·cm⁻¹. Badany poziom zasolenia spowodował istotny spadek wskaźników biometrycznych, decydujących o walorach dekoracyjnych żeniszka meksykańskiego, tj. liczby kwiatostanów, wysokości łodygi, liczby liści oraz zawartości chlorofilu. Zasolenie powodowało istotny wzrost koncentracji sodu i chloru oraz spadek zawartości wapnia we wszystkich analizowanych organach. Zmiany w zawartości potasu były zróżnicowane. Zasolenie powodowało wzrost koncentracji K w liściach i korzeniach, a spadek w łodygach i kwiatach. Sorbent jonitowy BIONA 111 okazał się dobrym komponentem gleb zasolonych. Powodował podwyższenie parametrów decydujących o wartości dekoracyjnej żeniszka meksykańskiego, jak również ograniczał dostępność jonów zasalających (Na⁺ i Cl⁻), powodując równocześnie wzrost akumulacji potasu oraz wapnia.
The boundary between beneficial and phytotoxic levels of selenium (Se) is narrow, and both induce alteration in plant growth and their physiology. In this study, the influence of two Se forms (selenite or selenate) with different concentrations (2–80 lM) on cucumber plants was investigated. The toxicity threshold for selenate and selenite was determined at the concentrations of 80 and 20 lM, respectively. In the Se-exposed plants, the growthpromoting effect was found at 6 lM of selenite and at 6–20 lM of selenate. The root activity considerably increased with increasing selenite concentrations suggesting the upregulation of mitochondrial dehydrogenases activity. Selenite treatment also impaired photosynthetic pigments accumulation and chlorophyll fluorescence parameters. Moreover, Se exerted a dual effect on lipid peroxidation in roots: at low concentrations it inhibited this process, whereas at high concentrations it enhanced the accumulation of harmful lipid peroxides. Under low Se concentrations (\10 lM), the accumulation of Se in shoots was similar in the presence of selenate and selenite. When Se concentration was[10 lM, the accumulation of Se in shoots was greater in selenate-exposed than seleniteexposed plants. However, in the roots the Se concentrations were always higher after selenite exposure comparing to selenate. The N level in plants was generally maintained constant, while the remaining macronutrients (especially K, P, and S) concentrations were significantly changed depending on the form and concentrations of Se. These results imply that an application of either selenate or selenite at concentrations\10 lM may be potentially used for biofortification of cucumber with Se and changes in plant macronutrient contents are not expected under these conditions.
The aim of the present study was to evaluate the possibility of using a protein hydrolysate, Hemozym N-K 4.5-6, as a component of salinized soil in the cultivation of flossflower (Ageratum houstonianum Mill., Asteraceae). The experiment was focused on the yield and decorative value of A. houstonianum, grown under different concentrations of NaCl and/or Hemozym. Ageratum houstonianum plants were grown in the soil under different NaCl salinity (EC: 0.28 – as control or 3.25 dS m−1 – salt stress) or/and Hemozym dose (0, 0.07 or 0.14 ml kg−1). The results of the experiment imply that A. houstonianum is sensitive to salinity. The application of Hemozym to both unsalinized and salinized soils caused an increase in the yield of the plant organs (roots, stems, leaves, and inflorescence), the number of leaves, and the chlorophyll content without significant changes in the carotenoids. Moreover, an increase in the number and size of first-order inflorescences (heads) as well as more intensive flower color were observed. Thus, it can be stated that the protein hydrolysate studied can be a beneficial component of both salinized and unsalinized soils in the cultivation of A. houstonianum.
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