Elementi retkih zemalja - itrijum i više biljke

Rare earth elements (REEs) form a chemically uniform group with very similar physical and chemical properties. The REEs include the elements scandium, yttrium, and the lanthanides from lanthanum to lutetium. They are widely distributed and present in all parts of the biosphere. REEs are required in industry, agriculture, medicine, biotechnology, environmental problems and many other fields. Lately, many experiments show their positive or negative, first of all nonspecific, effect on life processes of higher plants as well as growth and yield of cultivated species, but the physiological mechanisms are still not well understood. It has been determined that yttrium is widely distributed in plants, as well as that certain plant species uptake yttrium at different extent. Its highest accumulation is in the root and the leaf. Although yttrium was discovered more than two centuries ago, its effect on higher plants - their anatomical and morphological built, physiological and biochemical processes etc. - is very little known. One of the basic reasons is that yttrium, as well as other REEs elements, according to current knowledge, is not biogenic for higher plants and - wider - for live organisms. The objective of this paper is to concisely show previous knowledge about yttrium in the plant world.Elementi retkih zemalja (REEs) su iz hemijski uniformnih grupa sa veoma sličnim fizičkim i hemijskim osobinama. REEs uključuju elemente kao što su: skandijum, itrijum i lantanide od lantana do lutecijuma. Oni su široko rasprostranjeni i prisutni u svim delovima biosfere. REEs se koriste u industriji, poljoprivredi, medicini, biotehnologiji, kod problema zaštite životne sredine i u mnogim drugim poljima. U novije vreme, u mnogobrojnim ogledima je utvrđeno njihovo pozitivno ili negativno, pre svega nespecifično, dejstvo na životne procese viših biljaka kao i na rastenje i prinos gajenih vrsta, ali fiziološki mehanizmi dejstva još uvek nisu razjašnjeni. Utvrđeno je da je itrijum široko rasprostranjen u biljnom svetu, kao i da pojedine biljne vrste itrijum u različitoj meri usvajaju. Najveće je njegovo nakupljanje u korenu i listovima. Iako je itrijum otkriven pre više od dva veka, o njegovom dejstvu na više biljke, na njihovu anatomsku i morfološku građu, fiziološke i biohemijske procese i dr. veoma malo je poznato. Jedan od osnovnih razloga za to je da itrijum, kao i ostali elementi REEs prema dosadašnjim saznanjima nisu biogeni za više biljke i šire za žive organizme. Cilj ovog pregleda je da u sažetom obliku prikaže dosadašnja saznanja u vezi sa itrijumom u biljnom svetu

Management of soil organic carbon in maintaining soil productivity and yield stability of winter wheat

The objective of this study was to estimate how soil organic carbon influences winter wheat yield in the South Pannonian Basin. The treatments evaluated were: fertilized 3 year and 2 year crop rotation, fertilized wheat monoculture and unfertilized 3 year and 2 year crop rotation in the 38 years of continuous cropping (1970-2007). These treatments showed a declining trend of soil organic carbon in the 0-30 cm soil layer, respectively. On average, the plow-layer of the treatments lost 10% of soil organic carbon found at the beginning of the investigated period. The plow-layer of the unfertilized treatments reached a possible soil organic carbon threshold (1.16%) after balance on decomposition and formation was observed. We found that soil organic carbon preservation coupled with proper management such as crop rotation and fertilization is important for preserving soil productivity, and when soil organic carbon increases it could benefit winter wheat yield. Obtained results are valuable for developing a sustainable cropping technology for winter wheat and soil conservation

Mikrobiološka svojstva zemljišta pod povrćem - osnova za kontrolu plodnosti

Microorganisms are important elements in the soil-plant system. They are indicators of fertility and/or degradation processes taking place in the soil. Dominance of beneficial groups of microorganisms control the processes of synthesis and decomposition and determine soil quality for production of organic food. Reduced diversity of microorganisms is an indication of soil degradation and its low usefulness as a habitat for fauna, microbes and plants. Microbiological analyses of soil under peas, string beans, tomato pepper and cabbage in different locations (Bečej, Dala, Futog) showed that the number and biodiversity of microorganisms may be used to assess soil applicability for production of organic food. Biological activity of the soil was evaluated on the basis of the following parameters: total number of microorganisms, numbers of diazotrophs (Azotobacter and free N-fixing bacteria), ammonifiers, actinomycetes, fungi and the activity of dehydrogenase enzymes. Dehydrogenases (oxidoreductases) are fundamental in the enzymatic systems of all microorganisms. The dehydrogenase activity is an indicator of the microbiological redox system in the soil and it may serve as a measure of the microbial oxidative activity. The microbiological properties of the analyzed soils (average results) showed their high biological value. The total numbers of bacteria and ammonifiers ranged up to xlO8, of Azotobacter up to xlO3, free N-fixing bacteria up to xlO6, of fungi up to xlO4, and of actinomycetes up to xlO5.Mikroorganizmi su značajna karika u sistemu zemljište-biljka. Dominantnost korisnih grupa mikroorganizama usmeravaju procese sinteze i razgradnje i određuje kvalitet zemljišta za proizvodnju zdravstveno bezbedne hrane. Smanjena raznovrsnost mikroorganizama je indikacija degradacije i plodnosti zemljišta, kao staništa za faunu, mikrobe i biljke. Mikrobiološka istraživanja zemljišta pod graškom boranijom, paradajzom, paprikom kupusom na različitim lokalitetima (Bečej, Dala, Futog) pokazuju da se na osnovu zastupljenosti mikroorganizama i njihove bioraznovrsnosti delimično može izvršiti karakterizacija zemljišta za proizvodnju zdrave hrane. Biološka aktivnost zemljišta (biogenost) praćena je na osnovu sledećih parametara ukupnog broj mikroorganizama, zastupljenosti diazotrofa (Azotobacter-a i oligonitrofila), amonifikatora, aktinomiceta, gljiva i aktivnosti enzima dehidrogenaze. Dehidrogenaze su fundament u enzimatskim sistemima svih organizama. Aktivnost dehidrogenaze je indikator mikrobiološkog redoks sistema u zemljištu i mogu biti dobra mera oksidativne aktivnosti. Mikrobiološka svojstva ispitivanih zemljišta (prosečni rezultati) pokazuju visoku biogenost zemljišta. Zastupljenost ukupnog broja bakterija, i amonifikatora kreće se čak do x IO8, Azotobacter-a do xlO, oligonitrofila do xlO6, brojnost gljiva xlO4, a aktinomiceta do xlO5. Velika zastupljenost korisnih mikroorganizama koji učestvuju u procesima azotofiksacije i usvajanja fosfora omogućavaju biljci lakše usvajanje hraniva potrebnog za rast i razviće

Classification of Jerusalem artichoke accessions by linear discriminant analysis of mineral concentration in tubers and leaves

Linear discriminant analysis (LDA) was used to classify 138 accessions of Jerusalem artichoke (Helianthus tuberosus L.). The analysis was performed using mineral element concentrations of tubers and leaves for N, P, Ca, Mg, K, Fe, Mn, Zn and Cu. Higher classification accuracy was obtained using tuber (92.8%) than leaf (78.3%) mineral concentrations. Elements that contributed most to discrimination were Zn, Mg, and Cu for tubers and P, Mg, Zn and Cu for leaves. Accession separation in LDA figures was acceptable. Three distinctive groups that matched accession origins from the USA, Montenegro and cultivars were found according to tuber mineral concentrations. Leaf mineral concentrations provided a LDA graph where accessions from Montenegro and cultivars were grouped in two distinctive groups while accessions from the USA overlapped mostly with cultivars and to a certain degree with Montenegrin accessions. The obtained results indicate that LDA of tuber mineral composition can be useful as an additional tool for classification of Jerusalem artichoke accessions according to their origin using data of five elements (Na, Zn, Mg, Cu, Fe and K)

Superkritična ekstrakcija organohlornih pesticida iz vode

Recoveries of solid phase disk extraction and supercritical fluid extraction of natural groundwater samples were compared in this study. Deionised water sample (1 dm3) was spiked with a mix of lindan (g-HCH) and its metabolites (a-HCH, b-HCH, d-HCH) at level of 2.25 ng l-1 of each component. Extraction of spiked groundwater was performed by C-18 solid phase disks. Captured analytes were eluted from the disk in two different ways: 1) eluate obtained by the use of a solvent was evaporated to dryness and then again dissolved in acetone and 2) elution with supercritical fluid (CO2). Extracts were analysed by GC-ECD and an internal standard. Recoveries of extracts achieved with supercritical elution were much better than those with classical elution with a solvent.U ovom radu su upoređeni prinosi čvrsto fazne ekstrakcije i superkritične ekstrakcije pesticida iz vode. U 1 dm3 dejonizovane vode dodata je mešavina lindana i njegovih metabolita u koncentraciji od 2,25 ng/dm3 za svaki analit. Ekstrakcija vode je izvedena upotrebom C-18 ekstrakcionih diskova. Analiti su sa diska eluirani na dva načina: 1) eluat dobijen upotrebom rastvarača uparen je do suva i ponovo rastvoren u acetonu, i 2) elucija sa superkritičnim fluidom (CO2). Dobijeni ekstrakti su analizirani upotrebom GC-ECD i internog standarda. Prinosi dobijeni superkritičnom ekstrakcijom su značajno viši od prinosa dobijenih eluiranjem analita pomoću rastvarača

Tolerancija klijanaca pšenice na visoke koncentracije bora

Present in excessive amounts, micronutrient boron may become toxic for plants. The aim of this study was to investigate boron tolerance in seedlings of 12 wheat (Triticum aestivum L.) genotypes treated with boric acid. Selection criterion was root growth suppression in the presence of boron, which varied between 15.2 (Apache) and 46.3% (Renan). Root lengths on control and root growth suppression on treatments were not correlated. Boron content and dry weight of seedlings varied in vast intervals in all groups on control, as well as on treatments, which is probably caused by different boron tolerance mechanisms. Root growth suppression in genotypes Apache, Trakija and Bezostaja 1 was less than 20% and they may be considered as boron tolerant. Renan, Fundulea 4, Magdalena, Pergamino Gaboto and Donjecka 48 are marked as boron sensitive owing to more than 30% shorter roots on boron treatments. Norin 10/Brevor 14, Radika, Žitarka and Mironovska 808 were medium tolerant to excess boron.Mikroelement bor može imati toksično dejstvo na više biljke ukoliko se u spoljašnjoj sredini nade u visokoj koncentraciji. Cilj rada je bilo ispitivanje tolerancije na bor kod klijanaca 12 genotipova pšenice (Triticum aestivum L.) tretiranih bornom kiselinom. Selekcioni kriterijum je bila redukcija rasta korena u prisustvu bora, koja je varirala između 15,2 (Apache) i 46,3% (Renan). Nije zabeležena korelacija između dužine korenovog sistema na kontroli i redukcije rasta korena na tretmanima. Sadržaj bora i masa suvih klijanaca su varirali u širokim intervalima u svim grupama, i na kontroli i na tretmanima, čemu su verovatno uzrok različiti mehanizmi tolerancije na bor. Kod genotipova Apache, Trakija i Bezostaja 1 je redukcija rasta korena bila manja od 20% i oni bi se mogli smatrati tolerantnim na bor. Renan, Fundulea 4, Magdalena, Pergamino Gaboto i Donjecka 48 su svrstani u grupu osetljivih genotipova. Redukcija rasta korena je u ovoj grupi iznosila preko 30%. Sorte Norin 10/Brevor 14, Radika, Žitarka i Mironovska 808 su bile srednje tolerantne na visoke koncentracije bora

Occurrence and distribution of the cyclodiene-type organochlorine pesticides in soils of Vojvodina Province, Serbia

Aldrin, endrin and dieldrin are highly toxic and persistent cyclodiene-type organochlorine pesticides. Although these compounds have been banned over the last few decades in many countries, they can still be found in the environment, especially in the agricultural soil. In order to determine the residue levels of cyclodiene-type organochlorine pesticides in soils of Vojvodina Province, and to obtain detailed information on their spatial distribution, 1370 soil samples under different land uses were collected from Vojvodina Province and analyzed for the presence of aldrin, dieldrin and endrin. The residues of those pesticides residues of those pesticides residues of those pesticides residues of those pesticides residues of those pesticides residues of those pesticides residues of those pesticides were detected in the soils of Vojvodina in measureable concentrations and dieldrin was the most dominant compound in the soil. However, the concentrations of analysed cyclodiene-type organochlorine pesticides in the most soil samples from Vojvodina province were lower than Dutch target values for soil quality. Soil organic matter and clay content were found to be positively associated with aldrin content while clay content was found to be negatively associated with endrin

Influence of photoperiod on vegetation phases and tuber development in topinambour (Helianthus tuberosus L.)

A topinambour collection was analyzed to determine the genetic variability of 141 accessions in reaction to the length of day (light), its influence on vegetative and flowering phases, tuber number and mass. Day length significantly influenced flowering, which started with the first shorter days (15.6 h) in the third decade of June, while the majority of accessions flowered in the third decade of August (13.3 h). Differences between accessions were statistically significant for the analyzed phenotype traits. A significantly longer vegetative phase was found in Montenegrin accessions in comparison to the other groups of origin. Duration of the vegetative phase was significantly and positively correlated to tuber mass and negatively to their number, while duration of the reproductive phase had an opposite effect. For further work on topinambour breeding, it would be important to describe the mechanism of photoperiodic control of flowering initialization. Only by obtaining accessions neutral to the photoperiod could topinambour become a cultivated crop

Plodnost oranica ratarskih proizvodnih rejona Vojvodine u privatnom vlasništvu

The paper presents the results of soil fertility analysis for different crop growing areas of Vojvodina, Serbia. The analysis was conducted on a total of 76,868 plowland samples, accounting for 87% of the total number of samples tested in a larger project. On average, the neutral soil reaction, which is the most favorable type of reaction for crop production, was found in one quarter of all samples in our study. The percentage of samples with such reaction ranged from 12.6% (northern Bačka) to 46.5% (northern Srem). Looking at the free CaCO3 content by area, the highest mean value (10.54%) and proportions of calcareous (30.6%) and highly calcareous (53.1%) samples were found in northern Bačka, while the lowest values of these parameters were recorded in northern Srem. When it comes to the soil humus content, all three areas of Srem were found to be mostly slightly humic, as according to our analysis they had between 72.1 and 83.3% of samples that were slightly humic and only a small proportion (16.2-27.3%) of samples that are characterized as humic. Considering the readily available phosphorus content in Vojvodina as a whole, our analysis has shown that only one third of the soils in the province have an optimum supply of this element. What is of concern is that a considerable proportion of our samples were determined to be either very poor (6.9%) or poor (15.5%) in phosphorus, while about 7% had harmful or toxic levels of this macronutrient. In the case of the levels of readily available potassium, the largest number of the samples had either an optimum or high supply of the element. The sum of such samples ranged from 77.4 to 94.1% depending on the area.U radu su prikazani rezultati analize plodnosti zemljišta izdvojeni u odnosu na proizvodne rejone u Vojvodini. Analiza je obuhvatila 76.868 uzoraka zemljišta koji pripadaju oraničnom načinu korišćenja, što predstavlja 87% od ukupnog broja uzoraka. Neutralna reakcija zemljišta, koja je i najpovoljnija za biljnu proizvodnju, zastupljena je u 1/4 uzoraka i u zavisnosti od regiona kreće se od 12,6% (severna Bačka) do 46,5% (severni Srem). Ako se posmatra sadržaj slobodnog CaCO3 po rejonima, najveća srednja vrednost (10,54%) kao i zastupljenost u klasama karbonatno (30,6%) i jako karbonatno (53,1%) utvrđena je za rejon severna Bačka, a najniže vrednosti ovih karakteristika za rejon severni Srem. Rezultati ispitivanja obezbeđenosti zemljišta humusom pokazuju da sva tri rejona u Srema većim delom pripadaju slabo humoznoj klasi i to od 72,1% do 83,3% sa veoma malim udelom uzoraka humoznih zemljišta 16,2% do 27,3%. Analiza sadržaja lakopristupačnog fosfora za celokupno područje Vojvodine pokazuje da se u klasu optimalne obezbeđenosti zemljišta fosforom može svrstati samo trećina uzoraka. Zabrinjavajuće je da znatan deo uzoraka spada u vrlo siromašnu (6,9%) i siromašnu klasu (15,5%), dok oko 7% pripada klasama sa štetnim i toksičnim sadržajem ovog makrohraniva. Najveći broj uzoraka u pogledu sadržaja lakopristupačnog kalijuma u ispitivanim proizvodnim rejonima nalazi se u klasama optimalne i visoke obezbeđenosti, čija se suma kreće u intervalu od 77,4% do 94,1%

Određivanje sadržaja metribuzina u formulacijama pesticida primenom elektroanalitičke metodologije

The work presents results of the determination of metribuzin content in commercial pesticide formulations by applying chronopotentiometry with thin film mercury electrode as an electrochemical sensor. In the analyzed pesticide formulations, a single well defined reduction peak of metribuzin is observed at the potential around -880 mV. The content of the herbicide in commercial formulations is determined using the calibration curve method, by applying the initial potential of -0.21 V, and the final potential of -1.10 V. Recovery values based on the declared and found content of the active ingredient are in the range from 100.67% to 101.68%, with the values of relative standard deviation lower than 1.00%, indicating high accuracy and precision of the presented method