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The lipopolysaccharide (O) and flagellar (H) surface antigens of Escherichia coli are targets for serotyping that have traditionally been used to identify pathogenic lineages. These surface antigens are important for the survival of E. coli within mammalian hosts. However, traditional serotyping has several limitations, and public health reference laboratories are increasingly moving towards whole genome sequencing (WGS) to characterize bacterial isolates. Here we present a method to rapidly and accurately serotype E. coli isolates from raw, short read WGS data. Our approach bypasses the need for de novo genome assembly by directly screening WGS reads against a curated database of alleles linked to known and novel E. coli O-groups and H-types (the EcOH database) using the software package srst2. We validated the approach by comparing in silico results for 197 enteropathogenic E. coli isolates with those obtained by serological phenotyping in an independent laboratory. We then demonstrated the utility of our method to characterize isolates in public health and clinical settings, and to explore the genetic diversity of >1500 E. coli genomes from multiple sources. Importantly, we showed that transfer of O- and H-antigen loci between E. coli chromosomal backbones is common, with little evidence of constraints by host or pathotype, suggesting that E. coli ‘strain space’ may be virtually unlimited, even within specific pathotypes. Our findings show that serotyping is most useful when used in combination with strain genotyping to characterize microevolution events within an inferred population structure.

Based on the comparative analysis of gross margins in 2006 and 2011, the economic impact of winter wheat production on farms in the Republic of Serbia was estimated. The subject of the analysis was variable costs for purchased seed, fertilizers, pesticides, and contract harvesting services. Based on the analysis of the gross margin for winter wheat, it was noted that the value of production (VP), total variable costs (TVC) and gross margin (GM) were significantly higher in 2011 than in 2006. In 2011, VP was higher due to a significantly higher yield and the higher price of winter wheat grain. In addition to higher prices of all inputs, the increase in variable costs was mostly influenced by the higher price of fertilizer. Comparing the two time periods in winter wheat production, it was concluded that the value of GM in 2011 increased by 30%. Na osnovu uporedne analize vrednosti bruto marži u 2006. i 2011. godini procenjen je ekonomski efekat proizvodnje ozime pšenice na poljoprivrednim gazdinstvima u Srbiji. Analizirani su varijabilni troškovi, koji su se odnosili na utrošak novčanih sredstava za nabavku semena, đubriva, pesticida i ugovorene usluge za žetvu. Na osnovu analize kalkulacija bruto marži za ozimu pšenicu konstatovano je da su u odnosu na 2006. vrednost proizvodnje (VP), ukupni varijabilni troškovi (UVT) i bruto marža (BM) bili značajno veći u 2011. godini. U 2011. godini veća VP uslovljena je značajno većim prinosom i višom cenom zrna ozime pšenice. Na povećanje varijabilnih troškova, pored viših cena svih inputa, u najvećoj meri uticala je cena đubriva. Poređenjem ova dva vremenska perioda u proizvodnji ozime pšenice, vrednost BM u 2011. godini bila je veća za 30%.

The lipopolysaccharide (O) and flagellar (H) surface antigens of Escherichia coli are targets for serotyping that have traditionally been used to identify pathogenic lineages. These surface antigens are important for the survival of E. coli within mammalian hosts. However, traditional serotyping has several limitations, and public health reference laboratories are increasingly moving towards whole genome sequencing (WGS) to characterize bacterial isolates. Here we present a method to rapidly and accurately serotype E. coli isolates from raw, short read WGS data. Our approach bypasses the need for de novo genome assembly by directly screening WGS reads against a curated database of alleles linked to known and novel E. coli O-groups and H-types (the EcOH database) using the software package srst2. We validated the approach by comparing in silico results for 197 enteropathogenic E. coli isolates with those obtained by serological phenotyping in an independent laboratory. We then demonstrated the utility of our method to characterize isolates in public health and clinical settings, and to explore the genetic diversity of >1500 E. coli genomes from multiple sources. Importantly, we showed that transfer of O- and H-antigen loci between E. coli chromosomal backbones is common, with little evidence of constraints by host or pathotype, suggesting that E. coli 'strain space' may be virtually unlimited, even within specific pathotypes. Our findings show that serotyping is most useful when used in combination with strain genotyping to characterize microevolution events within an inferred population structure.

The lipopolysaccharide (O) and flagellar (H) surface antigens of Escherichia coli are targets for serotyping that have traditionally been used to identify pathogenic lineages. These surface antigens are important for the survival of E. coli within mammalian hosts. However, traditional serotyping has several limitations, and public health reference laboratories are increasingly moving towards whole genome sequencing (WGS) to characterize bacterial isolates. Here we present a method to rapidly and accurately serotype E. coli isolates from raw, short read WGS data. Our approach bypasses the need for de novo genome assembly by directly screening WGS reads against a curated database of alleles linked to known and novel E. coli O-groups and H-types (the EcOH database) using the software package srst2. We validated the approach by comparing in silico results for 197 enteropathogenic E. coli isolates with those obtained by serological phenotyping in an independent laboratory. We then demonstrated the utility of our method to characterize isolates in public health and clinical settings, and to explore the genetic diversity of >1500 E. coli genomes from multiple sources. Importantly, we showed that transfer of O- and H-antigen loci between E. coli chromosomal backbones is common, with little evidence of constraints by host or pathotype, suggesting that E. coli 'strain space' may be virtually unlimited, even within specific pathotypes. Our findings show that serotyping is most useful when used in combination with strain genotyping to characterize microevolution events within an inferred population structure.

Objective of the research were phenotypic and genetic correlation coefficients of three species of Sorghum genus - forage sorghum S. bicolor Moench. (genotype NS-Džin), Sudan grass S. sudanense L. (genotype Zora) and interspecies hybrid S. bicolor x S. sudanense (genotype Siloking). Studies were carried out on samples of plant material from the first cut. The following morphological-productive traits were studied: plant height, number of leaves per plant, mass of leaves on the stem, average stem mass and yield of green biomass. In the analysis of genetic and phenotypic coefficients, differences depending on the impact on studied morphological-productive traits are observed. The highest value of the stem height was recorded in Sudan grass (2.281 m), as well as number of leaves per plants (7.917). The greatest mass of leaves per plant was established in forage sorghum (49.05 g), and the highest average stem mass was recorded in interspecies hybrid plants (80.798 g). Variation of morphological-productive indicators per species was significant and very significant. Coefficients of simple correlations indicate the presence of very strong to almost complete, statistically very significant positive correlations, so these effects were expected. Plant height and number of leaves were not directly but indirectly statistically significant to yield of green biomass and varied from insignificant and very weak to sporadically medium strong and statistically significant. [Projekat Ministarstva nauke Republike Srbije, br. TR 31078]

The study shows the results of a four-year study on the effects of Siforga, a certified organic fertilizer on the yield and market quality of the root of the parsley variety Berliner medium long. The researched fertilizer quantities were at the rates of 500, 1.000, 2.000 and 3.500 kg ha-1 and the control treatment was a plot where no organic fertilizer was applied. Field trials were conducted in the spring cycle of parsley growing, from 2005 to 2008, in Starcevo, on anthropogenic soil of subtype chernozem with signs of gley in loess. The results of these study show that the lowest root yield was found in the control treatment (23.22 t ha-1), while the highest yield was found in the treatment with 1.000 kg ha-1 of Siforga (37.03 t ha-1). The best market quality of parsley root, that is, the largest portion of 1st class roots had 3.500 kg ha-1 at rate of Siforga, whereas the poorest quality was obtained at 500 kg ha-1 rate of Siforga (75.11%).Key words: Root parsley, organic fertilizer, root yield, market quality.

The aim of this study was to determine the effects of three different inoculation methods with selected Azotobacter chroococcum strains on productive and technological traits of sugar beet, as well as on the total number of microorganisms and azotobacter in rhizosphere. The results of this two-year study showed that effectiveness of the tested inoculation methods in increasing root yield and sugar content varies greatly, depending on year and azotobacter strains. Effectiveness of inoculation methods was not largely impacted by year on granulated sugar. Achieved granulated sugar yield was significantly higher by using pre-sowing azotobacter application, than by using seed inoculation. A significantly increased number of microorganisms in sugar beet rhizosphere was determined, not only by using pre-sowing azotobacter application but also by using sugar beet seed inoculation. Pre-sowing azotobacter application and inter-row cultivation both caused an equal increase in the number of these bacteria in sugar beet rhizosphere (42.2% and 46.9%). Use of sugar beet seed inoculation caused an increase of 33.7% in the number of azotobacter. In order to achieve higher effectiveness in applying azotobacter on productive and technological traits of sugar beet, and considering determined interaction between a certain year, an inoculation method and a strain, it is necessary for future research to focus on determining efficiency of these strains when they are in a mixture. Cilj ovog rada je utvrđivanje uticaja tri različita načina inokulacije sa sojevima Azotobacter chroococcum na proizvodne i tehnološke osobine šećerne repe i ukupnu brojnost mikroorganizama i brojnost azotobaktera u rizosferi. Na osnovu dvogodišnjih istraživanja utvrđeno je da je efektivnost ispitivanih načina inokulacije na povećanje prinosa korena i sadržaj šećera značajno varirala u zavisnosti od godine i soja azotobaktera. Uticaj godine na efektivnost inokulacije azotobakterom nije bio od većeg značaja za prinos kristalnog šećera. Pri inkorporaciji azotobaktera neposredno pre setve ostvaren je značajno bolji prinos kristalnog šećera u poređenju sa inokulacijom semena. Utvrđena je značajno povećana brojnost mikroorganizama u rizosferi šećerne repe pri inkorporaciji azotobaktera neposredno pre setve i inokulacijom semena šećerne repe. Inkorporacija azotobaktera neposredno pre setve i prvog međurednog kultiviranja uslovila je podjednako povećanje brojnosti ove bakterije u rizosferi šećerne repe (42,2% i 46,9%). Inokulacijom semena šećerne repe ostvareno je povećanje brojnosti azotobaktera za 33,7%. S obzirom da je u radu utvrđena interakcija između godine, načina inokulacije i soja, a u cilju postizanja veće efektivnosti pri primeni azotobaktera na proizvodne i tehnološke osobine šećerne repe, neophodno je buduća istraživanja usmeriti ka utvrđivanju efektivnosti ovih sojeva kada su u smeši.

In sugar beet production, one of the most important factors that affect the yield, apart from genetic properties, is the use of mineral fertilizers. Considerate amounts of mineral fertilizers are used in sugar beet production. However, if agroecological conditions are not optimum, mineral fertilizers cannot be completely absorbed, which may lead to soil contamination. Therefore, research has been focusing on ways of using atmospheric nitrogen by means of nitrogen-fixing bacteria. Numerous researches have proved that one part of mineral fertilizers can be replaced by biological nitrogen. The aim of this research was to determine the effect of genotype, azotobacter and the amount of mineral fertilizers on the root yield of sugar beet and on the microbiological activity of the sugar beet rhizospheric soil. Three hybrids of sugar beet were used during the two years of the research. The seed of the hybrids was inoculated with three strains of azotobacter. Various amounts of NPK were used (0;30;60;90 kg/ha). At the end of the vegetation period, the following were determined: root yield, total number of bacteria, number of azotobacter, oligotrophic bacteria, ammonifiers, fungi, and actinomycetes in soil. Dehydrogenase activity was measured. The results were processed statistically (analysis of variance for factorial trials) and the effect of the factors was determined upon the expected mean square values. The yield was mainly affected by the amount of mineral fertilizers. However, the effect of mineral fertilizers was different with different inoculation treatments. The effect of the examined factors was dependant upon genotype, amount of mineral fertilizers, inoculation and the year of trials. The interaction between genotype, mineral fertilizers, inoculation and the year of trials was the factor that had the greatest effect on the number of almost all the examined soil microorganisms.

Plant growth promoting rhizobacteria (PGPR) are a group of diverse soil bacteria which stimulate the growth of the host plant. It has been shown that Azotobacter chroococcum may be used as biofertilizer for increasing the yield and improving technological characteristics of sugar beet. The effect of three different ways of inoculation of sugarbeet with Azotobacter chroococcum on the production features of sugar beet and microbiological status of rhizosphere soil has been tested. One variety of sugar beet, Drena, was included in the tests in the region Rimski Šančevi, Novi Sad, during 2008 and 2009. Five strains of Azotobacter chroococcum (1, 5, 8, 10 and 14) were used as microbiological fertilizers. There were three variations of inoculation: (A) incorporation in the soil, (B) before the fi rst cultivation, and (C) applying the liquid culture of strain on the seed before sowing. The highest increase in yield of sugar beet roots 6.25 t ha-1 and yield of white sugar 0.91 t ha-1 was achieved with strain 10 with variant of inoculation of soil before the first cultivation. In both years, a positive effect of Azotobacter chroococcum was observed on the total number of microorganisms in the rhizosphere. Ispitan je efekat tri različita načina inokulacije šećerne repe sa sojevima Azotobacter chroococcum na parametre prinosa šećerne repe i mikrobiološki status zemljišta. U ispitivanjima je korišćena sorta Drena, a eksperiment je bio lociran na Rimskim Šančevima u toku 2008. i 2009. Kao mikrobiološko đubrivo korišćeno je pet sojeva Azotobacter chroococcum. Inokulacija je izvršena na tri načina: (A) inkorporacijom sojeva u zemljište pre setve, (B) inkorporacija sojeva u zemljište pred prvu međurednu kultivaciju i (C) nanošenjem inokuluma na seme pre setve. Najveće povećanje u prinosu korena od 6,25 t ha-1 i u prinosu kristalnog šećera od 0,91 t ha-1 dobijeno je sa sojem 10 na varijanti inokulacije zemljišta pre prve međuredne kultivacije. U obe godine dobijen je pozitivan efekat na ukupan broj mikroorganizama i broj azotobaktera u rizosferi.

The lipopolysaccharide (O) and flagellar (H) surface antigens of Escherichia coli are targets for serotyping that have traditionally been used to identify pathogenic lineages of E. coli. As serotyping has several limitations, public health reference laboratories are increasingly moving towards whole genome sequencing (WGS) for the rapid characterisation of bacterial isolates. Here we present a method to rapidly and accurately serotype E. coli isolates from raw, short read sequence data, leveraging the known genetic basis for the biosynthesis of O- and H-antigens. Our approach bypasses the need for de novo genome assembly by directly screening WGS reads against a curated database of alleles linked to known E. coli O-groups and H-types (the EcOH database) using the software package SRST2. We validated our approach by comparing in silico results with those obtained via serological phenotyping of 197 enteropathogenic (EPEC) isolates. We also demonstrated the utility of our method to characterise enterotoxigenic E. coli (ETEC) and the uropathogenic E. coli (UPEC) epidemic clone ST131, and for in silico serotyping of foodborne outbreak-related isolates in the public GenomeTrakr database.

Trail with sugar beet was set up during three years. Yield parameters were analyzed on five different origins of sugar beet varieties. Variety had a statistically significant affect on the yield sugar beet. The average yield for all tested varieties was 54.25 t ha-1. The highest average yield was achieved by varieties Chiara, 72.58 t ha-1, and Otis, 64.55 t ha-1 the variety Severina the lowest, 36.76 t ha-1. The variety Severina had the highest average crystal sugar content, 16.65%. Crystalline sugar yield, as the most important indicator of sugar beet yield, statistically significantly depended on the variety. Quality, namely technological root value largely depends of variety. Coarseness of the root was in inverse proportion to the content of sugar. Ogledi sa šećernom repom izvođeni su tokom tri godine. Analizirani su parametri rodnosti pet sorti šećerne repe različitog porekla. Sorta je imala statistički značajan uticaj na prinosa korena šećerne repe. Prosečan prinos korena za sve testirane sorte iznosio je 54,25 t ha-1. Najviši prinos imale su sorte Chiara, 72,58 tha-1 i Otis, 64,55 t ha- 1, a sorta Severina najniži, 36,76 tha-1. Sorta Severina imala je najveći sadržaj kristalnog šećera, 16,65%. Prinos kristalnog šećera, kao najvažniji pokazatelj rodnosti šećerne repe, statistički je značajno zavisio od sorte. Tehnološka vrednost korena u velikoj meri zavisila je od sorte. Krupnoća korena bila je u obrnutoj proporciji sa sadržajem kristalnog šećera.

Aim: To study the diversity of commensal Escherichia coli populations shed in faeces of cattle fed on different diets. Methods and Results: Thirty Brahman-cross steers were initially fed a high grain (80%) diet and then randomly allocated into three dietary treatment groups, fed 80% grain, roughage, or roughage + 50% molasses. Up to eight different E. coli isolates were selected from primary isolation plates of faecal samples from each animal. Fifty-two distinct serotypes, including nine different VTEC strains, were identified from a total of 474 E. coli isolates. Cattle fed a roughage + molasses diet had greater serotype diversity (30 serotypes identified) than cattle fed roughage or grain (21 and 17 serotypes identified respectively). Cluster analysis showed that serotypes isolated from cattle fed roughage and roughage + molasses diets were more closely associated than serotypes isolated from cattle fed grain. Resistance to one or more of 11 antimicrobial agents was detected among isolates from 20 different serotypes. Whilst only 2.3% of E. coli isolates produced enterohaemolysin, 25% were found to produce α-haemolysin. Conclusions: Diverse non-VTEC populations of E. coli serotypes are shed in cattle faeces and diet may affect population diversity. Significance and Impact of the Study: This study provides new information on the serotype diversity and phenotypic traits of predominant E. coli populations in cattle faeces, which could be sources of environmental contamination.

Two hundred verocytotoxigenic and 216 non-verocytotoxigenic Escherichia coli (VTEC and non-VTEC), isolated from a variety of sources were tested for their resistances to 11 antimicrobial agents. The strains included isolates from domestic food animals and both symptomatic and asymptomatic infections in man. A much higher level of resistance was found among the non-VTEC than among the VTEC, regardless of source. The resistant VTEC isolated from animals were predominantly from specimens associated with sick animals. Antibiotic resistance was detected in only four of the 59 (6.8 %) VTEC of human origin, whereas more of the human non-VTEC possessed antibiotic resistance determinants. It was particularly noteworthy that 24/87 (28 %) strains isolated from healthy babies, who had neither contact with antibiotics nor had gastrointestinal symptoms for at least 2 weeks prior to the specimen being taken, were resistant to one or more of the antibiotics tested.

The effect of storage was studied on grain metabolites, functional properties and digestibility of three oat cultivars selected in Serbia – Dunav, Vrbas and NS Tara. During the 12 and 24 months of storage, there was a decrease on average in total proteins (10.98% and 15.95%) lipids (7.55% and 11.82%), crude cellulose (6.65% and 14.77%) and starch concentration (6.48% and 9.48%), and an increase in total ash concentration (4.8% and 9%) and dry matter (4.53% and 5.92%). Storage period caused a decrease in β-glucan concentration. The concentration of total phenolics (28.79–41.19%) and caffeic acid markedly decreased after 24 months of storage. The storage period significantly influenced the ferric reducing ability (FRAP) (36.34–43.12%) and the DPPH radical scavenging activity (76.92–237.14%). Organic matter digestibility of oat grains was slightly changed, but remained over 70%. Based on the present study, oat grain should not be stored longer than 12 months since phenolics contribute markedly to health promoting effect of oats.

Environmental conditions significantly influence agricultural production, i.e. they are one of the main factors that affect its efficiency. Continuous monitoring of economic results makes it possible to identify the basic elements of revenues and expenditures in production of major agricultural crops, and use these data to plan future production – in other words, to choose the right enterprise for respective environmental conditions. The gross margin is a quick and efficient indicator used to analyse an enterprise when considering economic indicators of different enterprises and choosing the most efficient one in economic terms. In this paper we used the gross margin to compare the two production years with different production conditions, but on the same farms. Therefore, gross margin was used as an adequate indicator that aims to show the difference which is in function of various agro-ecological conditions, price and yield within the period of two years. The paper used the questionnaire carried out in 2011 and 2012 on a total of 69 chosen leader farms from the territory of 11 stations of the Agricultural Extension Service of Serbia. The questionnaire collected data on revenues and expenditures based on which gross margins for maize were calculated. The main indicator of this calculation is the gross margin, which is the difference between the value of production (value of the primary and the secondary product) and total variable costs that covers seed costs, fertilizer costs, costs of plant protection products, diesel fuels and contracted services (for sowing, harvest and labour). In these periods climatic conditions differed significantly. In 2012 there was considerably less precipitation with higher air temperatures, which was one of the main reason for reduced yields per area unit. In 2012, yields decreased by 28%, while price per kilogram of maize increased by about 37%, reducing total value of production by about 1%. It was estimated that total variable costs increased by 6%, while the gross margin was reduced by about 8%.

The effect of different agro-ecological conditions on morphoproductive properties of buckwheat cultivar Novosadska was investigated during 2011-2012 at three different localities. The types of soil on which the experiments were conducted were as follows: the eutric cambisol - in Valjevo, the chernozem - in Nova Pazova and the grey forest soil in Nova Varoš. Agro-ecological conditions affected the growth and productivity of the buckwheat crops at all three localities. The highest yields per unit area were obtained on the chernozem-type soil (1.65 t ha-1), while the average yields on the less fertile soils in the hilly and mountainous regions of Serbia were 1.31 t ha-1 on the grey forest soil and 0.80 t ha-1 on the eutric cambisol. The results showed that buckwheat can be successfully grown on different soil types, since the experiments on all locations were carried out without fertilization, i.e. using the natural fertility of the soil. Ispitivan je uticaj različitih agroekoloških uslova na morfološkoproduktivne osobine heljde sorte Novosadska u periodu od 2011-2012. na tri različita lokaliteta. Tipovi zemljišta na kome su postavljeni ogledi su: gajnjača - lokalitet Valjevo, černozem - lokalitet Nova Pazova i sivo šumsko zemljište na lokalitetu u Novoj Varoši. Agroekološki uslovi na sva tri posmatrana lokaliteta uticali su na rast i produktivnost heljde. Najveći prinosi zrna heljde po jedinici površine dobijeni su na zemljištu tipa černozem (1,65 t ha-1), dok na zemljištima manje prirodne plodnosti brdsko-planinskog područja Srbije, prosečan prinos bio je 1,31 t ha-1 na sivom šumskom zemljištu, a na gajnjači 0,80 t ha-1. Dobijeni rezultati su pokazali da se heljda može uspešno gajiti na našim zemljištima, budući da su ogledi na svim ispitivanim lokalitetima izvedeni bez prihrane tj. na prirodnoj plodnosti zemljišta.

Experiments were conducted during 2011-2012, at three localities in Serbia (Valjevo, Nova Varoš and Nova Pazova). The seed of spelt wheat cultivar Nirvana was used, having been selected at the Institute of Field and Vegetable Crops in Novi Sad. The objective of the research was to assess the effect of agro-ecological conditions on morphological and productive properties of spelt wheat grown on different types of soils. The effect of the locality was significantly expressed in all tested morphological properties of spelt wheat (plant height, number of spikelets, number of grains per spikelet), while meteorological conditions (year) affected spike length and grain mass per spike significantly. The average grain yield from all three localities was 3.20 t ha-1. A considerably higher yield was achieved on chernozem, locality Nova Pazova (3.89 t ha-1). The comparison of the grain yields from Valjevo (eutric cambisol) and Nova Varoš (grey forest soil) did not show any significant differences. Ispitivanja su sprovedena tokom 2011-2012 godine, na tri lokaliteta u Srbiji (Valjevo, Nova Varoš i Nova Pazova). Korišćeno je seme krupnika sorte Nirvana, selekcionisana u Institutu za ratarstvo i povrtarstvo, Novi Sad. Cilj istraživanja je bio da se oceni uticaj agroekoloških uslova na morfološke i produktivne osobine pod različitim tipovima plodnosti zemljišta. Uticaj lokaliteta značajno se ispoljio kod svih ispitivanih morfoloških osobina krupnika (visina biljke, broj klasića, broj zrna u klasiću), a meteorološki uslovi (godina) su značajno uticali na dužinu klasa i masu zrna u klasu. Prosečan prinos zrna krupnika na sva tri lokaliteta iznosio je 3,20 t ha-1. Značajno veći prinos ostvaren je na černozemu, lokalitet Nova Pazova (3,89 t ha-1). Poređenjem prinosa zrna na lokalitetima Valjevo (gajnjača) i Nova Varoš (sivo šumsko zemljište) nisu utvrđene značajne razlike.

Objective of the research were phenotypic and genetic correlation coefficients of three species of Sorghum genus - forage sorghum S. bicolor Moench. (genotype NS-Džin), Sudan grass S. sudanense L. (genotype Zora) and interspecies hybrid S. bicolor x S. sudanense (genotype Siloking). Studies were carried out on samples of plant material from the first cut. The following morphological-productive traits were studied: plant height, number of leaves per plant, mass of leaves on the stem, average stem mass and yield of green biomass. In the analysis of genetic and phenotypic coefficients, differences depending on the impact on studied morphological-productive traits are observed. The highest value of the stem height was recorded in Sudan grass (2.281 m), as well as number of leaves per plants (7.917). The greatest mass of leaves per plant was established in forage sorghum (49.05 g), and the highest average stem mass was recorded in interspecies hybrid plants (80.798 g). Variation of morphological-productive indicators per species was significant and very significant. Coefficients of simple correlations indicate the presence of very strong to almost complete, statistically very significant positive correlations, so these effects were expected. Plant height and number of leaves were not directly but indirectly statistically significant to yield of green biomass and varied from insignificant and very weak to sporadically medium strong and statistically significant. Predmet istraživanja ove studije su fenotipski i genetički koeficijenti korelacije tri vrste roda Sorghum, i to krmni sirak S. bicolor Moench. (genotip NSDžin), sudanska trava S. sudanense L. (genotip Zora) i interspecies hibrid S. bicolor x S. sudanense (genotip Siloking). Ispitivanja su vršena na uzorcima biljnog materijala iz prvog otkosa, Proučavane su sledeće morfološko-produktivne osobine: visina biljke, broj listova po biljci, masa listova na stablu, prosečna masa stabla i prinos zelene biomase. Analizom genetičkih i fenotipskih koeficijenata uočavaju se razlike i zavisnosti u delovanju na ispitivane morfološko-produktivne osobine. Najveću vrednost visine stabla imala je sudanska trava (2,281 m), kao i broj listova po biljci (7,917). Najveća masa listova po biljci bila je u krmnog sirka (49,05 g), a najveću prosečnu masu stabla imale su biljke interspecies hibrida (80,798 g). Variranja ovih morfološko-produktivnih pokazatelja po vrstama bila su signifikantna i vrlo signifikantna. Koeficijenti prostih korelacija ukazuju na postojanje vrlo jakih do skoro potpunih, statistički vrlo značajnih pozitivnih veza, ovakvi efekti su se mogli očekivati. Visina biljke i broj listova nisu bili direktno statistički značajni na prinos zelene biomase, ali indirektno jesu i varirali su od beznačajnih i jako slabih do sporadično srednje jakih i statistički značajnih.

This study characterizes the 21.4 kilobase plasmid pECTm80 isolated from Escherichia coli strain 80, an α hemolytic human clinical diarrhoeal isolate (serotype O108:H-). DNA sequence analysis of pECTm80 revealed it belonged to incompatibility group X1, and contained plasmid partition and toxin-antitoxin systems, an R6K-like triple origin (ori) replication system, genes required for replication regulation, insertion sequences IS1R, ISEc37 and a truncated transposase gene (Tn3-like ΔtnpA) of the Tn3 family, and carried a class 2 integron. The class 2 integron of pECTm80 contains an intact cassette array dfrA1-sat2, encoding resistance to trimethoprim and streptothricin, and an aadA1 gene cassette truncated by the insertion of IS1R. The complex plasmid replication system includes α, β and γ origins of replication. Pairwise BLASTn comparison of pECTm80 with plasmid pE001 reveals a conserved plasmid backbone suggestive of a common ancestral lineage. Plasmid pECTm80 is of potential clinical importance, as it carries multiple genes to ensure its stable maintenance through successive bacterial cell divisions and multiple antibiotic resistance genes. © 2012 Dawes et al.

The experiment focused on examining the effect of a mixture of azotobacter strains on the early growth of maize, grain yield and microbiological activity in rhizospheric soil of three maize hybrids: Tisa, NS5010 and NS444 ultra. Before seeding, the mixture of azotobacter strains was applied to one half of the experimental plot.The use of azotobacter led to an increase in the number of microorganisms. The mixture of azotobacter strains stimulated the early growth of maize to a great extent. With Tisa hybrid, the plants were up to 5 cm higher than the control plants and with NS444 ultra, the plants were up to 19,63 cm taller than the control plants. The grain yield in the variants with azotobacter increased with all three hybrids. The highest increase in yield was in NS5010 hybrid: 641 kg ha-1, in Tisa 403 kg ha-1 and in NS444 ultra, the grain yield increased by 396 kg ha-1.

The aim of the investigation was to examine the productive characteristics of the most successful and widely used maize hybrids. The paper shows the grain yield of two mid-early maize hybrids: ZP 544 and NS 444 ultra, as well as the yield of six late maturing hybrids: NS640, Zenit, ZP 684, ZP 704, ZP 677 and ZP 735. Both of the mid - early hybrids had a high grain yield. The ZP 544 hybrid achieved the yield of 9,411 t/ha wheareas the NS444 ultra hybrid achieved 9,1 t/ha. Concerning the late maturing hybrids, the highest yield was observed in NS640, Zenit and ZP684 (11,450 t/ ha, 11,196 t/ha and 10,346 t/ha). ZP 704 and ZP 677 had a signitificantly lower yield than the previous three hybrids (9,667 t/ha and 9,488 t/ha). The ZP 735 hybrid gave a yield of 8,190 t/ha which was the lowest yield of all the examined late maturity hybrids. According to the results of the experiment, the best hybrids to be used in the locality of Futog are NS640, Zenit and ZP 684. Cilj rada je da se sagledaju produktivne mogućnosti hibrida iz ogleda na određenom lokalitetu, do sada već dobro poznatih i zapaženih hibrida kukuruza iz šire proizvodnje. Prikazani su rezultati prinosa zrna dva srednje rana hibrida kukuruza: ZP 544, NS 444 ultra, i šest kasnostasnih: NS 640, Zenit, ZP 684, ZP 704, ZP 677, ZP 73. Visoku rodnost u svojstvu prinosa zrna iskazala su oba posmatrana srednje rana hibrida kukuruza. Hibrid ZP 544 ostvario je prosečan prinos suvog zrna 9,411 t/ha, NS 444 ultra 9,100 t/ha. Od kasnostasnih hibrida kukuruza najveću produktivnost u svojstvu prinosa zrna za posmatrani period iskazali su hibridi: NS 640, Zenit i ZP 684. NS 640 je relizovao prosečan prinos od 11,450 t/ha, Zenit 11,19t/ha6, a ZP 684 10,346 t/ha. Hibridi ZP 704 i ZP 677 sa ostvarenim prinosom zrna od 9,667t/ha i 9,488 t/ha, statistički su sa značajno nižom produktivnošću u posmatranom svojstvu od prethodna tri, a hibrid ZP 735 sa prosečnim prinosom zrna od 8,190 t/ha iskazao je visokoznačajno nižu produktvnost od svih kasnostasnih hibrida u ogledu. Prema rezultatima iz ogleda, po visini ostvarenog prinosa zrna stabilna i visoka proizvodnja kukuruza na futoškom ataru bila bi, ako se u sortimentu gajenja nađu hibridi: NS 640, Zenit i ZP 684.

Two typical coliforms from an intestinal biopsy from an adult case of bloody diarrhoea carried genes encoding intimin-β, stx 1 and ehxA, and produced verocytotoxin 1 and enterohaemolysin in culture. Both were biochemically typical Escherichia coli O5:H-, apart from producing urease. Such O5 isolates represent a human pathogenic E. coli lineage. © 2005 SGM.

Two typical coliforms from an intestinal biopsy from an adult case of bloody diarrhoea carried genes encoding intimin-beta, stx(1) and ehxA, and produced verocytotoxin 1 and enterohaemolysin in culture. Both were biochemically typical Escherichia coli O5 :H(-), apart from producing urease. Such O5 isolates represent a human pathogenic E. coli lineage.