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Winery wastewater treatment plants generally face severe nutrient deficiency, and therefore conventional technologies and supplementary nutrient dosing strategies may fail. The purpose of the paper is to show how traditional way of dosing N-source for marginal availability to nutrient deficient influents results in poorly settling activated sludge regardless of the application of aerated or non-aerated selectors. External N-source calculated for marginal availability resulted in nutrient deficiency due to the relatively high yield experienced (0.7 g biomass COD/g substrate COD). In the fully aerated system with overall N-deficiency, rapidly increasing overproduction of extracellular polysaccharide was experienced, leading to SVI (Sludge Volume Index) values up to 600 cm3 g−1. In the system with the non-aerated selector, initial nutrient deficiency could only be detected in the second reactor. Since neither overgrowth of floc-forming GAOs (Glycogen Accumulating Organisms) nor denitrification could be experienced, the non-aerated reactor operated as low-DO (Dissolved Oxygen) basin, attributing to the drastic overgrowth of filamentous bacteria leading to SVI values >1000 cm3 g−1. Since dosing external N-source for marginal availability is likely to cause severe biomass separability problems in activated sludge winery wastewater treatment, either pronounced N-overdosing and pre-denitrification or severe nutrient deficiency and GAO cultivation can rather be recommended.

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In order to decrease the organic load on the downstream domestic wastewater treatment plant, a three stage, fully aerated activated sludge system was established for the pretreatment of a vegetable processing wastewater. The results of the research verified that this design was inappropriate at the given, highly fluctuating wastewater quality. Nitrate formed through nitrification of the pea processing wastewater could not be denitrified, thus rising sludge occurred in the secondary clarifiers. On the other hand, during the corn campaign, severe deterioration of the COD (Chemical Oxygen Demand) removal efficiency, as well as the overproduction of extracellular polysaccharides leading to viscous bulking, were caused by the extremely high C/N ratio. In order to efficiently treat the wastewater of the vegetable processing industry, establishment of highly flexible systems with unaerated first stage proves to be necessary.

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Abstract  

An extensive investigation of elemental levels in cereals and their cultivation soils has been going on across the main production areas of mainland Portugal, with a view to an eventual biofortification of major cultivars through agronomic practices. Cereals are an obvious choice as primary vehicles for food-supplementation programs, especially in countries where they definitely weigh in the dietary intake (like Portugal), and regions whose geographical and/or pedological features may account for nutrient deficiencies in typical diets. Mature rye plants (Secale cereale L.; roots and grains) and local soils were collected in the summer of 2009 from two regions of northern Portugal, and put through k 0-standardized, instrumental neutron activation analysis (k 0-INAA). Overall, the results (elemental concentrations, enrichment factors, transfer coefficients) seem to confirm an efficient uptake of elements from soil and their translocation to the aerial parts of the plants, notably to the ones that really matter in human nutrition (grains).

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The polyamine (PAs), putrescine (Put), spermidine (Spd) and spermine (Spm) are small aliphatic amines that ubiquitous in all living organisms. PA metabolism in higher plants is involved in both biotic and abiotic stress responses, and also influenced by nutrient deficiency. Accumulated evidence suggests that in plants the cellular titers of PAs are affected by various nitrogenous compounds. Therefore, the present study analyzed the effects of different nitrogen levels viz. recommended doses of nitrogen (RDN, 120 kg N/ha), sub-optimal N dose (RDN −25%, 90 kg N/ha) and supra-optimal N dose (RDN +25%, 150 kg N/ha) on PA metabolism in grains of six wheat genotypes at 15 days post anthesis (DPA) and 30 DPA. The activities of polyamine synthesizing enzymes (arginine decarboxylase, ornithine decarboxylase), catabolizing (diamine oxidase, polyamine oxidase) and the PA content were increased at supra-optimal nitrogen dose as compared to RDN. Whereas at sub-optimal nitrogen dose, higher activity of polyamine catabolizing enzymes results in speeding up oxidation of various PAs to cope up with nitrogen deficiency in plant. In relation to PA content, Put was found to be higher at early stage whereas Spd and Spm were found to be higher towards mature stages of grain indicating the use of Put in grain filling process. Highly significant correlation was observed between PA metabolism, yield and nitrogen use efficiency at sub-optimal N dose as compared to supra-optimal dose.

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Sweet sorghum (Sorghum bicolor L. Moench cv. Róna) is a widely grown sugar crop that is used for bioenergy production. Since sorghum shows increased sensitivity to nutrient deficiency, the objective of this study was to reach an appropriate Cu level in plant tissues using various concentrations of Cu and ethylenediaminetetraacetic acid (EDTA) in order to enhance the photosynthetic activity and biomass production of plants. Copper accumulation increased in the root and stem of plants irrigated for 12 weeks with 0.1 μM CuCl2 both in the presence and absence of 300 μM EDTA and as a consequence, the plant-available Cu concentration in the soil extracts was lower at harvest. Although the copper content of leaves slightly increased, the transport of Fe and Mn, the microelements participating in light reactions of photosynthesis was negatively affected. In spite of this, 0.1 μM CuCl2 alone and with 200 or 300 μM EDTA enhanced the maximal CO2 assimilation rate (Amax) as a function of photon flux density (PPFD) and increased soluble sugar content in all plant parts. The dry mass of plants especially that of stems increased very significantly after 0.1 μM CuCl2 + 300 μM EDTA treatment. These results show that non-toxic concentration of copper in combination with suitable concentration of EDTA can enhance photosynthesis, biomass production, sugar content and the total copper accumulation in the shoot of sweet sorghum plants.

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In the present study, changes in the infectivity and effectiveness of four Glomus mosseae strains of different origin were investigated in calcareous loamy chernozem soils treated with Cd at three levels (0, 50, 100 mg Cd kg −1 ) in a pot experiment. Frequency of infection (F%), arbuscular richness (a%) and shoot dry matter, macro-(N, P, K, S, Ca, Mg) and microelements (Zn, Cu, Ni, Mn, Mo, Co) and the Cd content of the host plants were compared to determine whether there was any variability in infectivity and effectiveness between G. mosseae strains of different origin. Functional diversity was found in the infectivity and effectiveness of the studied G. mosseae strains. In Cd-treated soil, AMF inoculation was beneficial to the plant growth, P uptake and shoot Cd content of the host. However, the higher uptake of other macro- and microelements was noted for non-mycorrhizal plants compared to mycorrhizal plants. The lower shoot content of some elements did not cause nutrient deficiency in mycorrhizal plants. The present results support the hypothesis that in polluted soils, the development of mycorrhizal symbiosis has the potential for AMF to protect their hosts against Cd toxicity rather than to improve nutrient uptake.

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Növénytermelés
Authors: Nóra Bákonyi, Éva Gajdos, Brigitta Tóth, Marianna Marozsán, Szilvia Kovács, Szilvia Veres, and László Lévai

Összefoglalás

A növények tápanyagfelvétele a termés mennyiségét és a minőségét meghatározó egyik fő fiziológiai folyamat. A kedvezőtlen környezeti feltételek csökkentik a tápanyagfelvételt, a növény szervesanyag-felhalmozását, ezzel az elérhető termés mennyiséget is. A növénytermesztés eredményességét meghatározó, egyik legfontosabb abiotikus tényező a talaj pH-ja. Bár a talaj pH-jának hatása sokrétű, mégis az egyik leginkább kutatott terület a pH és a talajok felvehető tápanyagtartalmának összefüggése. Kísérleteinkben a tápoldat és az apoplazmatikus bikarbonát, valamint egy biotrágya (Phylazonit MC®) hatását vizsgáltuk laboratóriumi körülmények között, tápoldaton nevelt fiatal kukorica és uborka csíranövényekre. Meghatároztuk a növények relatív klorofill tartalmát, a hajtás és gyökér növekedését, szárazanyag-felhalmozását, elemtartalmát, különösen az egyik legfontosabb terméslimitáló elem, a vas felvételében. Megállapítottuk, hogy a környezet magas bikarbonát koncentrációja stresszként hat, a tápközeg pH-jának módosításán keresztül jelentősen befolyásolja a vizsgált folyamatokat. Megfigyelésünk alapján arra a következtetésre jutottunk, hogy a gyökér és a mezofillum sejtek tápanyagfelvétele azonos mechanizmus szerint történik. Ezen megfigyelésünk alátámasztja Marschner és Römheld (1994) eredményeit. A tápoldatba és az apoplazmába juttatott bikarbonát hatása hasonló, ami mögött a tápanyagfelvétel hasonló membránfolyamatait valószínűsítjük. A pH mellett a mezofillum sejtközötti járatainak bikarbonát koncentrációja is okozhat tápanyag hiányt (látens tápanyaghiány) megfelelő tápanyagellátás esetén is. Eredményeink szerint a bikarbonát okozta stresszhatás mérsékelhető volt egy baktérium tartalmú biotrágya (Phylazonit MC®) kiegészítő használatával. Feltételezzük, hogy a kedvező hatás mögött a baktériumok és a magasabb rendű növények tápanyag-felvételi hasonlóságai vannak.

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Hungarian national dietary survey, 2003–2004

Mikro-tápanyagok: ásványi sók

Orvosi Hetilap
Authors: Lajos Biró, Gábor Zajkás, Erika Greiner, Ildikó Szórád, Anna Varga, Andrea Domonkos, Helga Ágoston, Anikó Balázs, Erzsébet Mozsáry, József Vitrai, Dóra Hermann, Julianna Boros, Renáta Németh, Zsuzsanna Kéki, and Éva Martos

A 3. Országos Táplálkozási Vizsgálatban az adatgyűjtésre 2003-ban, az eredmények értékelésére 2004–2005-ben került sor. A 19 éven felüli lakosság 1179 főből álló mintájának energia- és tápanyagbeviteléről az Orvosi Hetilap 2005. év 34. számában jelent meg beszámoló, a jelen közlemény a mikrotápanyagok közül az ásványi sók beviteléről szól. Az eredményeket a szerzők elsősorban a két korábbi hazai táplálkozási vizsgálat adataival összehasonlítva, valamint magyar és nemzetközi ajánlásokhoz viszonyítva értékelték. Az ásványi anyagokat illetően kedvezőnek ítélhető a mindkét nemben megfelelő átlagos magnézium-, valamint a férfiak esetében az ajánlást kielégítő vas-, cink- és rézbevitel. Kedvezőtlen a mindkét nemben elégtelen kalcium- és a túlzott foszforbevitel, valamint a kalcium- és foszforbevitel aránytalansága. A kedvezőtlen eredmények közé tartozik a nők elégtelen vas-, cink- és rézbevitele, valamint a mindkét nemben rendkívül nagy nátriumbevitel. A szerzők hangsúlyozzák az egészséges táplálkozás elterjesztésének és az élelmiszeriparral való együttműködésnek a fontosságát az ásványianyag-hiányok megelőzése érdekében.

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The jasmonates, which include jasmonic acid and its methyl ester (MJ), play a central role in regulating the biosynthesis of many secondary metabolites, including flavonoids, and also are signaling molecules in environmental stresses. Synthesis of anthocyanins pigments is a final part of flavonoids pathway route. Accumulation of the pigments in young seedlings is stimulated by various environmental stresses, such as high-intensity light, wounding, pathogen attack, drought, sugar and nutrient deficiency. The anthocyanins take part in defense system against excess of light and UV-B light, and therefore it is probably main reason why young plant tissues accumulate enlarged levels of the pigments. The effects of exogenously applied MJ on level of anthocyanins, glycosides of apigenin, luteolin, quercetin and proanthocyanidins in seedlings of common buckwheat (Fagopyrum esculentum Moench) were studied. MJ decreased contents of all the found cyanidin glycosides and its aglycone in hypocotyls of buckwheat seedlings. However contents of particular anthocyanins in cotyledons of buckwheat seedlings treated with the plant hormone were not significantly different from the control. Applied doses of MJ did not affect levels of quercetin, apigenin and luteolin glycosides in the analyzed parts of buckwheat seedlings: cotyledons and hypocotyls. On the other hand, treatment of buckwheat seedlings with MJ clearly stimulated of proanthocyanidins biosynthesis in hypocotyls. We suggest that methyl jasmonate induces in hypocotyls of buckwheat seedlings the leucocyanidin reductase or anthocyanidin reductase, possible enzymes in proanthocyanidins synthesis, and/or inhibits anthocyanidin synthase, which transforms leucocyanidin into cyanidin. According to our knowledge this is the first report regarding the effect of methyl jasmonate on enhancing the accumulation of proanthocyanidins in cultivated plants.

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. 29 86 89 Gerloff, G. C. 1987: Intact-plant screening for tolerance to nutrient-deficiency stress. Plant & Soil , 99 , 3

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