Monitoring of residues of sulfonylurea in soil under real conditions by using high pressure liquid chromatography

U okviru doktorske disertacije razvijena je brza i selektivna metoda za određivanje i praćenje ostataka herbicida na bazi sulfonilurea (nikosulfuron, oksasulfuron, tribenuron metil, tritosulfuron, triasulfuron, rimsulfuron i prosulfuron) u zemljištu primenom visoko pritisne tečne hromatografije sa UV detektor sa nizom fotoosetljivih dioda (HPLC-UV-DAD). Razdvajanje sulfonilurea je izvedeno uz primenu Zorbax Eclipse XDB-C18 kolone. U cilju definisanja odgovarajućih uslova analize, ispitan je i definisan uticaj najznačajnijih eksperimentalnih faktora. Usvojeni su sledeći optimalni uslovi gradijentne elucije: mobilna faza acetonitril (A) i 0,1% sirćetna kiselina (B) t = 0 min, 52% A; t = 2-2,5 min, 47% A; t = 2,5-5 min, 52% A, pri konstatnom protoku od 1 mL min-1 i temperaturi kolone od 250C. Na osnovu odziva analitičkog signala, njegove reproduktivnosti i linearnosti, talasna dužina od 240 nm je usvojena kao odgovarajuća. Utvrđeno je da je uticaj matriksa bio izražen te je stoga za kvantitativno određivanje sadržaja SU u uzorcima zemljišta primenom HPLC-UV-DAD metode korišćena MMC kalibraciona kriva. Pri analizi ekstrakata nekontaminiranog zemljišta ostvarena je granica kvantitativnog određivanja za nikosulfuron, oksasulfuron, tribenuron metil, tritosulfuron, triasulfuron, rimsulfuron i prosulfuron od 3,16 μg kg-1, 3,40 μg kg-1, 3,76 μg kg-1, 4,13 μg kg-1, 3,60 μg kg-1, 3,04 μg kg-1 i 2,97 μg kg-1, redom. Za potrebe osetljivijih, selektivnijih i tačnijih određivanja SU u zemljištu, definisana je metoda uz primenu tečne hromatografije sa tandemskom masenom spektrometrijom (HPLC-MS-MS). HPLC-MS-MS je korišćena kao referntna tehnika za proveru rezultata koji su dobijeni primenom HPLC uz UV-DAD detektor. Definisan je efikasan postupak za pripremu uzoraka zemljišta u cilju hromatografskog određivanja SU. Najefikasnija ekstrakcija ostvarena je primenom smeše dihlormetanacetonitril (2:1, v/v), zakišeljene sirćetnom kiselinom (0,8%, v/v), uz dodatak uree (0,3 g/ 10g zemljišta). Postupak mikrotalasne estrakcije u zatvorenom sistemu omogućio je najbolje uslove za ekstrakciju SU. U cilju izdvajanja SU, iz matriksa ekstrakata zemljišta, primenjena je ekstrakcija na čvrstoj fazi (SPE) sa silika gelom kao adsorbensom. Definisana metoda za određivanje ispitivanih SU, kao i razvijeni postupak pripreme uzoraka, uspešno je primenjen u analizi realnih uzoraka zemljišta. Veoma dobre vrednosti testa povrata ostvarene pri analizi primenom HPLC-UV-DAD metode, potvrdile su pre svega ispravnost postupka pripreme uzoraka, a delom i kompletne metode. Tačnost razvijene metode za određivanje SU u zemljištu potvrđena je paralelnim analizama uzoraka zemljišta korišćenjem HPLC-MS-MS. Primenom Studentovog t-testa (upareni), utvrđeno je da se rezultati paralelnih analiza statistički značajno ne razlikuju (P=95%). Istraživanja u okviru disertacije obuhvatila su i praćenje disipacije nikosulfurona, rimsulfurona, oksasulfurona i prosufurona u različitim komercijalnim dozama primene tokom 50 dana u polju na tri različite dubine (0-15 cm, 15-30 cm i 30-45 cm), kao i laboratorijskim uslovima na dve temperature (250C i 300C). Vreme polurazgradnje (DT50) ispitivanih SU (nikosulfuron, oksasulfuron i prosulfuron) definisano Mitttag-Lefler-ovom funkcijom u ogledima u laboratorijskim uslovima na 250C iznosilo je 0,65 dana (50 g ha-1 a.k.), 0,64 dana (160 g ha-1 a.k.) i 0,66 dana (30 g ha-1 a.k.), redom, a na 300C za nikosulfuron 0,20 dana (50 g ha-1 a.k.) i prosulfuron 0,49 dana (50 g ha-1 a.k.). DT50 za ispitivane SU u polju, takođe definisano Mitttag-Lefler-ovom funkcijom, iznosilo je 72 minuta (0,05 dana), 0,23 dana, 0,12 dana i 0,15 dana, za nikosulfuron, rimsulfuron, oksasulfuron i prosulfuron, redom. Značajno veća disipacija koja je utvrđena istraživanjima u okviru ove disertacije najverovatnije je uzrokovana uticajem abiotičkih i biotičkih procesa, kao i faktora spoljašnje sredine.In this thesis a fast and selective method for determination and monitoring of residues sulfonylurea herbicides (SU) (nicosulfuron, oxasulfuron, tribenuron methyl, tritosulfuron, triasulfuron, rimsulfuron and prosulfuron) in soil, by applying high-performance liquid chromatography with UV detector with diode array diodes (HPLC-UV-DAD) was developed. The separation of the sulfonylurea was performed by use of a Zorbax Eclipse XDB-C18 column. In order to define appropriate conditions of analysis, the influence of the most significant the experimental factors was investigated and defined. The following optimal conditions for gradient elution: mobile phase acetonitrile (A) and 0.1% acetic acid (B) t = 0 min, 52% A; t = 2-2.5 min, 47% A; t = 2.5-5 min, 52% A were adopted at a constant flow rate of 1 mL min-1 and column temperature of 250C. On basis of the response of the analytical signal, its reproducibility and linearity, the wavelength of 240 nm was adopted as an appropriate. The influence of the matrix was expressed and therefore for the quantitative determination of investigated SU in soil samples application of HPLCUV- DAD methods was used MMC calibration curve. In the analysis of extracts of nocontaminated soil limits of quantitation for nicosulfuron, oxasulfuron, tribenuron methyl, tritosulfuron, triasulfuron, rimsulfuron and prosulfuron was achieved 3.16 μg kg-1, 3.40 μg kg-1, 3.76 μg kg-1, 4.13 μg kg-1, 3.60 μg kg-1, 3.04 μg kg-1 and 2.97 μg kg-1, respectively. The method by using liquid chromatography-tandem mass spectrometry (HPLC-MSMS) was defined in order to find more sensitive, more selective and more accurate way to determine concentration SU in soil. HPLC-MS-MS was used as the reference technique for checking results that have been obtained by HPLC with UV-DAD detector. An efficient procedure preparation of soil samples for the purpose chromatographic determination of SU was defined. Using a mixture of dichloromethane-acetonitrile (2: 1, v / v), acidified with acetic acid (0.8%, v / v), with the addition of urea (0.3 g / 10 g soil) was applied as the most effective way for extraction SU. Microwave extraction process in a closed system allowed the best conditions for the extraction of SU. In order to extract SU from matrix exctracts soil the solid phase the extraction (SPE) with silica gel as an adsorbent was used. The defined method for determination of investigated SU, as well as the developed procedure of sample preparation, was successfully applied in the analysis of real samples of soil. The correctness of procedure of sample preparation was confirmed with very good values of recovery test which was applied in the analysis by using HPLC-UVDAD. The accuracy of the developed method for determination of SU was confirmed by coupled analysis soil samples using HPLC-MS-MS. The results of parallel analysis does not differ significantly at 95% confidence level. It was obtained using Student t-test (paired). The method developed in this thesis was used for monitoring the dissipation of nicosulfuron, rimsulfuron, oxasulfuron prosufuron, in different commercial doses of application during 50 days in field at three different depths (0-15 cm, 15- 30 cm and 30-45 cm) and for laboratory conditions at two temperatures (25ºC and 30ºC). The half-life time (DT50) of investigated SU were calculated by use of Mitttag-Lefler function in experiments under laboratory conditions at 25ºC. The values of DT50 for nicosulfuron, prosufuron and oxasulfuron read: 0.65 days (50 g ha-1 a.k.), 0.64 days (160 g ha-1 a.k.) and 0.66 days (30 g ha-1 a.k.), respectively. In the same type of experiments at 30ºC we get DT50 for nicosulfuron equals 0.20 days (50 g ha-1 a.k.) and for prosulfuron equals 0.49 days (50 g ha-1 a.k.). The values of DT50 on experiments in field were obtain also by use of Mitttag-Lefler's function, and half-life times for nicosulfuron, rimsulfuron, oxasulfuron and prosufuron from the commercially recommended doses, equal 72 minutes (0.05 days), 0.23 days, 0.12 days and 0.15 days, respectively. Significantly greater dissipation which was determined in this thesis was probably caused by the influence of abiotic and biotic processes as well as environmental factors

Sulfonylurea herbicides residues analysis in soil

Prosulfuron, rimsulfuron, thifensulfuron-methyl and tritosulfuron are widely used sulfonylurea herbicides (SUs), applied in low-dose rates. However, these herbicides under specific conditions as low temperature, poor rainfall, microbial activity. high pH of soil, can remain at low concentrations in soil and can affect the growth of sensitive plants. This paper presents the method that we developed for determination of prosulfuron, rimsulfuron, thifensulfuron-methyl and tritosulfuron residues in soil. Determination and quantification were performed by HPLC/DAD using Agilent Zorbax SB-C18 column (3.0 mm*250 mm. 5 um particle size). Mobile phase was acetonitrile/0.1% CH3COOH solution. Analyzed SUs showed linear calibrations from 0.05 to 0.2 mg/ml with correlation coefficient (1°) above 0.990%. The recovery data were obtained by spiking blank soil samples at two concentration levels (2.5-5.0 mg/kg), yielding average recovery between 95.56 and 99.79%. Precision values expressed as relative standard deviation (RSD) were between 0.91-1.11% for all SUs herbicides for the intraday precision. Considering the obtained values of analytical parameters, the proposed method proved to be an efficient and sensitive method for the determination of prosulfuron, rimsulfuron, thifensulfuron-methyl and tritosulfuron in soil samples

Legal regulations of dangerous and harmful substances, the problem of pesticide residues in soil

Zemljište je neobnovijivi resurs i veoma dinamičan sistem, koji obavija mnogo funkcija i pruža usluge od vitalnog značaja za Ijudske delatnosti i opstanak ekosistema. Proizvodnja zdravstveno ispravne hrane, zaštita zdravlja Ijudi, životinjskog i biljnog svijeta, nesmetanog korištenja i zaštite prirode životne sredine mogući su jedino uz zaštitu poljoprivrednog zemljista od zagađenja. Zaštita poljoprivrednog zemljišta se sprovodi zabranom, ograničavanjem i sprečavanjem od direktnog unošenja te unošenja vodem i vazduhom štetnih materija i preduzimanjem drugih mera za očuvanje i poboljšanje njegove plodnosti. U radu su navedeni ključni aspekti regulatorne politike Srbije i zemalja u okruženju sa osvrstom na direktivu EU (91/414/EEC) za postojanost poljoprivrednih pesticida (aktivnih materija) u zemljištu. U radu je predstavijen Evropski regulatorni stav za zemljište po pitanju ne-ekstrahovanih ili vezanih pesticida i njihov uticaj na životnu sredinu kao i uticaj đubrenja na vezivanje pesticida u poljoprivrednom zemljištu.The paper set out key aspects of regulatory policy of Serbia and neighboring countries with regard to the EU directive (91/414/EEC) for the stability of agricultural pesticides (active substances) in soil. This paper presents European regulatory position regarding land for non-extracted or related pesticides and their impact on the environment and the impact of fertilization on the binding of pesticides in agricultural soil

Effects of environmental variation in time of filling seeds on oil content of rapeseed

U radu je analiziran uticaj temperature i padavina na prosečan sadržaj ulja,proteina, vlage i primesa uljane repice. Korišćeni su višegodišnji rezultati (2007-2018) kvaliteta semena uljane repice kao sirovine za dalju proizvodnju dobijeni od firme „Victoriaoil” a.d, Šid. Sadržaj ulja i proteina je kvantitativno svojstvo i uslovljeno je kako faktorima spoljašnje sredine tako i genotipa i njihovom interakcijom. Vremenski uslovi tokom vegetacionog perioda proizvodnje uljane repice, posebno temperatura i padavine imali su značajan uticaj na sadržaj ulja i proteina u semenu.This work analysed the influence of temperature and precipitation on the average content of oil, protein, moisture and yield of rapeseed. The results of long-term experiment (2007-2018) were used. The content of oil and protein is a quantitative property and conditioned both by environmental and genetic factors. Weather conditions had a significant impact on the content of oil and protein in grain during the growing rapeseed season, especially temperature and precipitation

Comparison of Two Different CEC Determination Methods Regarding the Soil Properties

Cation Exchange Capacity (CEC) is a parameter which reveals extent of the soil surface sites that can potentially retain cations by electrostatic forces. Different soil types vary in CEC values, which in turn depend on many factors (soil pH, texture, organic matter content, etc.). CEC is a good indicator of soil quality and fertility. CEC can be measured using different methods and it is difficult to recommend a universal one. The most commonly used methods include exchange of cations with a specific solution of known salt concentrations that are not present in the soil, followed by analytical detection of these cations by standard techniques. The aim of this study was to determine and compare the CEC and the amount of exchangeable cations measured on the same samples (n = 50) of soil with different characteristics, using two common methods (one with BaCl2 and the other with CH3COONH4 solution), and to determine their dependence on soil pH, content of organic matter and clay content. Correlation between the values of CEC measured with two different methods was very high (r=0.83). Still, significant difference between the two methods (F test, p ≤ 0.05) was noted. Transformation of the CEC values achieved by one method into the estimated values of the other method is possible. Very high correlation was observed between CEC (CECBaCl2 and CECCH3COONH4) and OM content in soil (r=0.78 and r=0.80), high correlation with soil pH (r=0.58 and r=0.52), and very weak or no correlation with clay content (r=0.12 and r=-0.04). Also, soil salt content influenced measured values of CEC (in CH3COONH4) and sum of exchangeable cations (in BaCl2)

Composition investigation of the sunflower seed of the latest NS confectionary hybrids

Because of the favorable amino acid composition of sunflower protein and low content of antinutritive components, the confectionary/non-oil sunflower seed is increasingly gaining in importance. This is why there is a need for increasing the number of this type of hybrids. Breeding new hybrids of different characteristics are obtained. In order to investigate the composition of the seed, three samples of the latest NS hybrids of second filial (F2) generation (NS-H-6792, NS-H-6489, NS-H-6311) were analyzed and compared with the results of the hybrid seed already-used (Cepko). The content of moisture was determined according to SRPS EN ISO 665, 2008, the content of the oil according to SRPS EN ISO 659, 2011, while the mass of 1000 seeds and the content of hull and kernels were made according to Karlović & Andrić, 1996. The moisture content ranged from 5.75±0.00% in the sample NS-H-6792 to 6.57±0.03%, in the sample NS-H-6489. The oil content was in the range of 25.62±0.22%, found in the sample NS-H-6311 to 23.12±0.16%, found in the sample NS-H 6489. The highest content of the hull was found in the NS-H-6792 sample, 46.74±0.80%, while the smallest content of the hull was found in the sample NS-H-6311 and amounted to 41.91±0.71%

Variability and correlations between soybean yield and quality components

The aim of this research was to determine variability and correlations between yield, protein content and oil content in soybean cultivars. The research was carried out on ten NS soybean cultivars in 2008, 2009 and 2010. All of the analysed traits significantly varied depending on cultivar and year. The highest yield in the analysed period was found in cultivar Proteinka (4,947 kg ha(-1)) which was significantly higher than that of cultivars Becejka, Tara, Afrodita and Diva. The highest average yield in 2010 was found in cultivars Irina (5,590 kg ha(-1)) and Bdejka (5,340 kg ha(-1)). The highest protein content was found in cultivars Afrodita and Galina, while the highest oil content was found in cultivars Alisa, Valjevka and Alisa. Significantly higher yield were obtained in 2010, while significantly higher protein and oil content was recorded in 2008. Yield was insignificantly positively correlated with oil content both in 2008, 2009 and 2010 (0.06, 0.31 and 0.17, respectively), and negatively but not significantly correlated with protein content (-0.06, -0.12 and -0.19, respectively). Oil content was significantly negatively correlated with protein content (-0.47(star)) in 2009, while in 2008 and 2010 this correlation was insignificant (-0.25, -0.11). This research is a basis for further breeding of soybeans with improved grain yield and content of protein and oil

Iskorišćenje i kapacitet proizvodnje hladno presovanog ulja semena uljanih i konzumnih hibrida suncokreta

U svetu, prema podacima Organizacije za hranu i poljoprivredu (Food and Agriculture Organization, FAO) i Departmana za poljoprivredu Sjedinjenih Američkih Država (United States Department of Agriculture, USDA) proizvodnja semena suncokreta raste. Takođe, u svetu rastu i potrebe za proizvodnjom ulja i visokokvalitetnih proteina, zbog čega su se izdiferencirali i hibridi suncokreta u cilju zadovoljenja pomenutih potreba na uljane i konzumne (neuljane, proteinske). Istraživanjem u ovom radu pokazano je da je proizvodnja ulja postupkom hladnog presovanja moguća i od konzumnih hibrida suncokreta, ne samo od uljanih, međutim razlike u iskorišćenju i kapacitetu tj. količini dobijenog ulja su značajne. Iskorišćenje ulja i semena bili su 2,12 i 2,17 puta veći kod uljanih u odnosu na konzumne hibride suncokreta, dok za 1 h kroz presu prođe 1,84 puta više semena i dobije se 3,89 puta više ulja, kod uljanih u odnosu na konzumne hibride suncokreta.According to the Food and Agriculture Organization (FAO) and the United States Department of Agriculture (USDA), world sunflower seed production is increasing. The needs for the production of oil and high-quality proteins are growing in the world, which is the reason for sunflower hybrids divergence in oily and confectionary (non-oily, protein) hybrids, in order to meet the mentioned needs. Research in the paper has shown that the production of oil by cold pressing is possible from confectionary sunflower hybrids, not only from oily, but the differences in the oil yield and amount of obtained oil are significant. Oil and seed yield were 2.12 and 2.17 times higher for oily compared to confectionary sunflower hybrids, while 1.84 times more seed and 3.89 times more oil of oily hybrids passed through the press in 1 hour compared to confectionary sunflower hybrids