Biology of fertilization and pomological traits of quince (Cydonia oblonga Mill.) cultivars

Код осам сорти дуње: Лесковачка, Врањска, Морава, Пазарџијска, Хемус, Асеница, Португалска и Тријумф испитиване су репродуктивне карактеристике, као и помолошке особине у београдском воћарском подручју, у периоду од 2010. до 2013. године. Методом светлосне микроскопије испитивани су: процес микроспорогенезе, клијавост полена и раст поленових цевчица in vitro, као и сингамија, постоплодни процеси и аномалије у грађи ембрионове кесице. Анализа морфолошких особина полена урађена је помоћу скенирајуће електронске микроскопије. Методом флуоресцентне микроскопије анализирани су квантитативни показатељи раста поленових цевчица (бројност и динамика раста), као и појава инкомпатибилности и специфичног раста поленових цевчица у тучку. Заметање плодова је утврђено у пољским условима. Стандардним методама проучаване су следеће помолошке особине: фенолошке особине (фенофазе од почетка вегетације до цветања, цветање и сазревање плодова, као и завршетак вегетације), морфолошке особине стабла, једногодишњег изданка, цвета, листа, плода и семена, родност и квалитет плода (хемијски састав и сензоричка оцена). Анализом процеса мејозе у микроспорогенези утврђено је да је он био у одређеном степену ирегуларан. Најправилнији ток мејозе и највећу клијавост полена имале су сорте Асеница и Тријумф, док је најнеправилнији ток мејозе и најмању клијавост полена имала сорта Лесковачка. На основу морфолошке анализе полена утврђено је да је облик поленових зрна варирао од пролатног (Лесковачка, Врањска, Морава, Хемус, Асеница и Тријумф) до перпролатног (Пазарџијска и Португалска). Орнаментика егзине код свих сорти је била стријатна, са мање или више паралелним лонгитудиналним гребенима. Динамика раста поленових цевчица кроз стубић и плодник тучка, сингамија, постоплодни процеси и рана ембриогенеза, као и заметање плодова првенствено су зависили од генотипа сорте, начина опрашивања и метеоролошких услова у време цветања. Код свих проучаваних сорти дуње установљен је бржи раст поленових цевчица, веће присуство ембриона, као и веће заметање плодова у варијанти слободног опрашивања у односу на самоопрашивање...Eight cultivars of quince: Leskovacka, Vranjska, Morava, Pazardzijska, Hemus, Asenica, Portugal and Triumph were the subject of investigating their reproductive characteristics, as well as pomological traits in the Belgrade fruit region, in the period from 2010 to 2013. Using light microscopy the following traits were studied: the process of microsporogenesis, pollen germination and growing of pollen tubes in vitro, as well as syngamy, post-fertilization processes and anomalies in the structure of embryo sac. The analysis of morphological traits of pollen was performed using scanning electron microscopy. Using the method of fluorescence microscopy, quantitative indicators of pollen tubes growing (number and growth dynamics) were analyzed, as well as incompatibility and unusual behavior of pollen tubes growth in the pistil. Fruit set was determined under field conditions. Standard methods were used to investigate the following pomological traits: phenological traits (phenophases from the beginning of vegetation to blooming, blooming, fruit ripening, as well as the end of vegetation), morphological traits of tree, shoot, flower, leaf, fruit and seed, productivity and fruit quality (chemical composition and sensory evaluation). Analyzing the process of meiosis in microsporogenesis, it was determined that it was irregular in some extent. The most regular course of meiosis and the largest pollen germination was noticed in Asenica and Triumph cultivars, while the most irregular course of meiosis and the smallest pollen germination was found in Leskovacka cultivar. Based on morphological analysis of pollen it is determined that the shape of pollen grains varied from prolate (Leskovacka, Vranjska, Morava, Hemus, Asenica and Triumph) to perprolate (Pazardzijska and Portugal). Ornamentation of the exine in all of the cultivars was striate, with more or less parallel longitudinal ridges. Dynamics of growing pollen tubes through the style and the pistil of ovary, syngamy, postfertilization processes and early embryogenesis, as well as fruit set primarily depended on the cultivar genotype, type of pollination and meteorological conditions during the blossoming period. In all of the investigated cultivars of quince, there was a faster growth of pollen tubes, greater presence of embryos, as well as higher fruit set in the variant of open pollination compared to self-pollination..

The use of information and communication technologies by enterprises in the European Union member countries

The paper analyzes the use of information and communication technologies (ICT) in enterprises in the European Union member states. The objectives of the analysis were to examine the level reached in the application of ICT in European enterprises and explore the differences in ICT usage that exist between the EU member states. The analysis is based on the Eurostat data on ICT usage in enterprises in the European Union countries (EU-28) for the years 2018 and 2017. The following indicators of ICT usage were analyzed: fixed broadband access, the speed of the internet connections, the presence of the Internet (enterprises having a website), the use of social media, the use of cloud computing services, e-commerce indicators (the share of the enterprises making e-sales and the share of e-commerce in the total turnover) and the indicators of e-business integration - the share of the enterprises using enterprise resource planning (ERP), customer relationship management (CRM) and the supply chain management (SCM) software applications. A comparative analysis of the EU countries by the value of these indicators was carried out. The main focus in the analysis was to identify the factors that influence the difference in the value of the ICT indicators between the countries. The analysis has shown that the regional position, the geographic characteristics, the size of the country and the level of its economic development are the factors that influence these differences.U radu se analizira primena informaciono-komunikacionih tehnologija (IKT) u preduzećima u zemljama članicama Evropske unije (EU). Ciljevi analize bili su da se ispita dostignuti nivo u primeni IKT u preduzećima i da se istraže razlike u korišćenju IKT koje postoje među zemljama članicama EU. U analizi su korišćeni podaci EUROSTAT-a o primeni IKT u preduzećima Evropske unije (EU-28) za 2017. i 2018. Analizirani su sledeći indikatori primene IKT u preduzećima: širokopojasna internet konekcija, brzina internet konekcije, prisustvo na internetu (posedovanje Web sajta), korišćenje društvenih medija, korišćenje cloud računarstva, indikatori e-trgovine (udeo preduzeća koja prodaju svoje proizvode preko interneta i učešće e-trgovine u ukupnom prometu), i indikatori integrisanosti e-poslovanja (udeo preduzeća koja koriste integralni poslovni software, software za upravljanje odnosima sa klijentima i softver za upravljanje lancem snabdevanja). Izvršena je komparativna analiza zemalja EU po vrednosti ovih indikatora, sa ciljem da se utvrdi koji faktori utiču na razlike u vrednosti indikatora među zemljama. Analiza je pokazala da su regionalni položaj, geografske karakteristike, veličina zemlje i dostignut nivo ekonomskog razvoja faktori koji utiču na ove razlike

The use of information and communication technologies by enterprises in the European Union member countries

The paper analyzes the use of information and communication technologies (ICT) in enterprises in the European Union member states. The objectives of the analysis were to examine the level reached in the application of ICT in European enterprises and explore the differences in ICT usage that exist between the EU member states. The analysis is based on the Eurostat data on ICT usage in enterprises in the European Union countries (EU-28) for the years 2018 and 2017. The following indicators of ICT usage were analyzed: fixed broadband access, the speed of the internet connections, the presence of the Internet (enterprises having a website), the use of social media, the use of cloud computing services, e-commerce indicators (the share of the enterprises making e-sales and the share of e-commerce in the total turnover) and the indicators of e-business integration - the share of the enterprises using enterprise resource planning (ERP), customer relationship management (CRM) and the supply chain management (SCM) software applications. A comparative analysis of the EU countries by the value of these indicators was carried out. The main focus in the analysis was to identify the factors that influence the difference in the value of the ICT indicators between the countries. The analysis has shown that the regional position, the geographic characteristics, the size of the country and the level of its economic development are the factors that influence these differences.U radu se analizira primena informaciono-komunikacionih tehnologija (IKT) u preduzećima u zemljama članicama Evropske unije (EU). Ciljevi analize bili su da se ispita dostignuti nivo u primeni IKT u preduzećima i da se istraže razlike u korišćenju IKT koje postoje među zemljama članicama EU. U analizi su korišćeni podaci EUROSTAT-a o primeni IKT u preduzećima Evropske unije (EU-28) za 2017. i 2018. Analizirani su sledeći indikatori primene IKT u preduzećima: širokopojasna internet konekcija, brzina internet konekcije, prisustvo na internetu (posedovanje Web sajta), korišćenje društvenih medija, korišćenje cloud računarstva, indikatori e-trgovine (udeo preduzeća koja prodaju svoje proizvode preko interneta i učešće e-trgovine u ukupnom prometu), i indikatori integrisanosti e-poslovanja (udeo preduzeća koja koriste integralni poslovni software, software za upravljanje odnosima sa klijentima i softver za upravljanje lancem snabdevanja). Izvršena je komparativna analiza zemalja EU po vrednosti ovih indikatora, sa ciljem da se utvrdi koji faktori utiču na razlike u vrednosti indikatora među zemljama. Analiza je pokazala da su regionalni položaj, geografske karakteristike, veličina zemlje i dostignut nivo ekonomskog razvoja faktori koji utiču na ove razlike

The use of information and communication technologies by enterprises in the European Union member countries

The paper analyzes the use of information and communication technologies (ICT) in enterprises in the European Union member states. The objectives of the analysis were to examine the level reached in the application of ICT in European enterprises and explore the differences in ICT usage that exist between the EU member states. The analysis is based on the Eurostat data on ICT usage in enterprises in the European Union countries (EU-28) for the years 2018 and 2017. The following indicators of ICT usage were analyzed: fixed broadband access, the speed of the internet connections, the presence of the Internet (enterprises having a website), the use of social media, the use of cloud computing services, e-commerce indicators (the share of the enterprises making e-sales and the share of e-commerce in the total turnover) and the indicators of e-business integration - the share of the enterprises using enterprise resource planning (ERP), customer relationship management (CRM) and the supply chain management (SCM) software applications. A comparative analysis of the EU countries by the value of these indicators was carried out. The main focus in the analysis was to identify the factors that influence the difference in the value of the ICT indicators between the countries. The analysis has shown that the regional position, the geographic characteristics, the size of the country and the level of its economic development are the factors that influence these differences.U radu se analizira primena informaciono-komunikacionih tehnologija (IKT) u preduzećima u zemljama članicama Evropske unije (EU). Ciljevi analize bili su da se ispita dostignuti nivo u primeni IKT u preduzećima i da se istraže razlike u korišćenju IKT koje postoje među zemljama članicama EU. U analizi su korišćeni podaci EUROSTAT-a o primeni IKT u preduzećima Evropske unije (EU-28) za 2017. i 2018. Analizirani su sledeći indikatori primene IKT u preduzećima: širokopojasna internet konekcija, brzina internet konekcije, prisustvo na internetu (posedovanje Web sajta), korišćenje društvenih medija, korišćenje cloud računarstva, indikatori e-trgovine (udeo preduzeća koja prodaju svoje proizvode preko interneta i učešće e-trgovine u ukupnom prometu), i indikatori integrisanosti e-poslovanja (udeo preduzeća koja koriste integralni poslovni software, software za upravljanje odnosima sa klijentima i softver za upravljanje lancem snabdevanja). Izvršena je komparativna analiza zemalja EU po vrednosti ovih indikatora, sa ciljem da se utvrdi koji faktori utiču na razlike u vrednosti indikatora među zemljama. Analiza je pokazala da su regionalni položaj, geografske karakteristike, veličina zemlje i dostignut nivo ekonomskog razvoja faktori koji utiču na ove razlike

The impact of education on entrepreneurs activity and employment among marginalized groups: an evidence of Serbia

Measuring human development and well-being is based on a numerous of indicators of social inclusion (Lelkes 2006). Mostly significant indicators of well-being include employment, health and education. When any individual or group is excluded from education or it is employed below the level of expertise, we can talk about the “marginalization”. Groups or individuals can be excluded from society on gender, religious and ethnic grounds or on the basis of a refugee status, physical and mental disabilities. There are multiple factors that make an impact on social exclusion. Most of all, economic restructuring of a system excludes certain groups from the labour market due to the fact that their skills and education level do not match the requirements of the new system. Beside that, certain population groups can be discriminated against because of various stereotypes, stigma and prejudice. In other words, various stereotypes, stigma and prejudice can be among the factors leading to their social and economic vulnerability. Therefore, reaching equality among all population groups and the absence of discrimination in contemporary society represent moral imperatives. Accordingly, the Europe 2020 Strategy pays special attention to social programs for the most sensitive social groups. These programs should enable their accelerated employment. Also, they are aimed at fighting all types of discrimination that exists. Addressing this issue is of special importance for Serbia on its path to EU accession. Despite the Anti-discrimination law was adopted in 2009, Serbia is still not among the most liberal and tolerant societies in Europe, where gender, age and other differences are respected. In line with this, educational institutions should play an important role and become more responsible in terms of providing support to the Romani, the disabled and those who are excommunicated and are not in an equal position with other groups. This is, perhaps, where we can find the key to overcoming inequalities and discrimination that starts back in school (Furlong et al. 2011). In this paper, special attention was paid to the following issues. These are: (a) the issues of determining the form of social exclusion that is the most common in Serbia; (b) determining the cause of the faster leaving the educational processes of marginalized groups compared to other population groups; (c) defining the development directions (forms and types) of education that would encourage learning and greater inclusion of these groups; (d) identifying the causes of difficult employment of marginalized groups in Serbia; (e) examining the possibilities for faster employment by fostering entrepreneurial activity and work in social enterprises

Uticaj promene dužine slobodnog sedla na promenu napona retencionih zuba i spoja jednostrane kompleksne parcijalne proteze

Background/Aim. Different types of dental restorations are used for the therapy of unilateral free-end saddle edentulism. Unilateral complex partial denture is one of the indications for the Kennedy class II partial edentulism. The abscence of major connector and denture plate is an advantage compared to the conventional restorations, because of better comfort and shorter period of adaptation. The aim of the study was to analyse the influence of free-end saddle length change on the behaviour of unilateral complex partial denture supporting structures. Methods. Stress levels of the canine and the first premolar as retentional teeth and the attachments were tested under the influence of physiological forces with the loading point shifting distally in relation to the saddle length change. A virtual real size 3D model of the fixed part of the restoration (the canine and the first premolar with milled crowns) was created using the CATIA computer program. It was connected to the mobile part of partial denture with the SD snap in latch attachment. Mobile part of the restoration was designed in the region of 2, 3 and 4 lateral teeth (second premolar, first, second and third molar). By using the finite element method (FEM) stress levels analysis was performed under the load of physiological forces of 150 N in the free-end saddle teeth zone. Results. The results of analysis show that physiological forces cause a different stress distribution on the abutment teeth and the attachment, depending on the saddle length. Conclusion. The stress level values obtained for the abutment teeth as well as the attachment are far lower than the marginal ones. The behaviour of the system changes under this defined stress, but no plastic deformation occurs.Uvod/Cilj. U terapiji jednostrano slobodnog sedla koriste se različiti oblici zubnih nadoknada. Jednostrana kompleksna parcijalna proteza (JKPP) jedna je od indikacija za bezubost klase Kenedi II. Odsustvo velike spojnice i protezne ploče predstavlja prednost u odnosu na konvencionalne nadoknade zbog boljeg komfora i kraćeg perioda adaptacije. Cilj rada bio je analiza uticaja promene dužine slobodnog sedla na ponašanje potpornih struktura JKPP. Metode. Ispitivani su naponi očnjaka i prvog premolara kao retencionih zuba i veze (spoja) pod dejstvom fizioloških sila sa pomeranjem tačke opterećenja distalno, u zavisnosti od dužine sedla. Primenom kompjuterskog programa CATIA u realnoj veličini urađen je virtulni 3D model fiksnog dela nadoknade (očnjak i prvi premolar sa namenskim krunama) koji je veza SD snap in latch priključena na mobilni deo parcijalne proteze. Mobilni deo nadoknade postavljen je u predelu dva, tri, odnosno četiri bočna zuba (drugi premolar, prvi, drugi i treći molar). Primenom metode konačnih elemenata obavljena je analiza naponskih stanja pri opterećenju fiziološkim silama od 150 N u predelu zuba slobodnog sedla. Rezultati. Analiza proračuna pokazala je da pod dejstvom fizioloških sila dolazi do različite raspodele napona na retencione zube i spoj u zavisnosti od dužine sedla. Zaključak. Dobijene vrednosti za napone kako na retencionim zubima, tako i na spoju, daleko su manje od graničnih. Pri zadatim naponima dolazi do promene ponašanja, ali ne i do plastične deformacije sistema

Incompatible pollen tubes in the quince style and their impact on fertilization success

Self-incompatibility presents one of the challenges in modern fruit production. It can be correlated with a lower yield of self-incompatible cultivars which also demand the planting of the pollinisers. The aim of this work was to investigate the phenomenon of incompatibility and its influence on fertilization success in quince (Cydonia oblonga Mill.), using the cultivars ‘Leskovacka’, ‘Vranjska’, ‘Morava’, ‘Pazardzijska’, ‘Hemus’, ‘Asenica’, ‘Portugal’ and ‘Triumph’. Incompatible pollen tubes were determined by using fluorescence microscopy. In two types of pollination (self-pollination and open pollination) pollen tubes showed signs of incompatibility, mostly in the upper third of the style. The most common sign of incompatibility is the formation of swelling at the tip of a pollen tube. Also, sometimes twisted, bifurcated, and short and thickened pollen tubes along their entire length are formed. The incompatibility was significantly more pronounced in the self-pollination than in the open pollination variant in all tested cultivars. The highest number of incompatible pollen tubes in both pollination types was present in the cultivar ‘Pazardzijska’, while the lowest number was present in the cultivars ‘Leskovacka’ and ‘Vranjska’. The appearance of incompatibility affected the degree of fertilization in quince. The results showed that only ‘Leskovacka’ and ‘Vranjska’ are self-compatible, while other studied cultivars (‘Morava’, ‘Pazardzijska’, ‘Hemus’, ‘Asenica’, ‘Portugal’ and ‘Triumph’) are self-incompatible. The results provide a good background for the future research of reproductive biology and also for adequate management of the quince orchards

Grašak i urov Tetovac - made in ranogvozdenodobni Leskovac, Deo drugi - ekstrakcija drevne DNK iz ugljenisanih semena sa nalazišta Hisar u južnoj Srbiji

The extracts were prepared from the samples of 3,200-year-old charred pea and bitter vetch seeds from the site of Hissar near Leskovac, South Serbia, using two different DNA extraction procedures. We used CTAB method with some modification and obtained low quantity of ancient DNA in comparison with the second method used - commercial available kit. After the extraction, a whole genome amplification using Phi29 DNA polymerase was performed. The amplified DNAs were used for PCR reaction using primers for 26S rDNA gene, which is located on the nuclear genome. The single band corresponding to 26S rDNA fragment from modern relatives was obtained. We conclude that DNA from charred pea and vetch seed can be extracted and used for further archaeobotanical analysis at the molecular level.Primenom dve različite procedure ekstrahovana je drevna DNK iz ugljenisanih semena graška i urova starih 3200 godina sa lokaliteta Hisar kod Leskovca. Korišćena je modifikovana CTAB metoda i dobijena je relativno mala količina drevne DNK u poređenju sa drugom primenjenom metodom - komercijalno dostupnim kitom za izolaciju DNK. Nakon ekstrakcije primenjeno je umnožavanje celog genoma pomoću Phi29 DNK polimeraze. Umnožena DNK je korišćena za PCR reakciju primenom prajmera za 26S rDNK gen, koji je lociran u jedarnom genomu. Dobijen je fragment iste veličine kao i PCR fragment 26S rDNK savremenih srodnika graška i urova. Može se zaključiti da je moguće ekstrahovati drevnu DNK iz ugljenisanih semena graška i urova i koristiti je za dalje arheobotaničke analize na molekularnom nivou

Pisum & Ervilia Tetovac: Made in Early Iron Age Leskovac, Part one: Two charred pulse crop storages of the fortified hill fort settlement Hissar in Leskovac, South Serbia

Arheološki lokalitet Hisar je gradinsko naselje Brnjičke kulturne grupe (gvozdeno doba I u Pomoravlju), podignuto na vrhu, odnosno na platou brda Hisar koje kontroliše zonu ušća Jablanice i Veternice u Južnu Moravu i najveći deo Leskovačke kotline. Prilikom arheoloških istraživanja 2005. godine u objektima koji se vezuju za Brnjica II a fazu (12. vek pre nove ere) pronađene su dve velike količine ugljenisanih semena graška (Pisum sativum L) i urova (Vicia ervilia (L) Willd). Zalihe ove dve zrnaste mahunarke bile su skoro čiste, sa malim procentom nečistoća koje su pre svega činili plodovi, pre svega žitarica, drugih mahunarki (sočivo - Lens culinaris Medik. i bob - Vicia faba L), ali i biljaka uljarica, što ukazuje da su grašak i urov bili odvojeno uzgajani, a potom i odvojeno skladišteni. Ovi nalazi, a pre svega nesvakidašnji nalaz zalihe graška, potvrđuju dugu tradiciju uzgajanja mahunarki u leskovačkom kraju.A lucky find of 2,572 charred pea (Pisum sativum L) seeds in a single archaeobotanical sample from the hill fort settlement Hissar near Leskovac represents a unique example in Bronze / Iron Age research in South East Europe. Another mass storage of bitter vetch (Vicia ervilia (L) Willd) from the same site and period (Brnjica cultural group, beginning of the Iron Age in the Morava valley) confirms a long tradition of the city of Leskovac region as a pulse crop production centre in modern Serbia. Both pulse storages were almost pure with small amount of admixture from other crops mainly cereals, other pulses, such as lentil (Lens culinaris Medik) and broad bean (Vicia faba L), and oil/fibre plants. Both pulses were cultivated as main crops and were stored separately

Pomološke osobine perspektivnih sejanaca maline sa žutom bojom ploda

From over a 100 seedlings obtained by open pollination of Meeker's yellow raspberry clone, 10 seedlings with yellow fruit were selected at the Experimental Station 'Radmilovac' of the Faculty of Agriculture, University of Belgrade. Phenological characteristics, as well as physical, chemical and sensorial fruit properties were investigated during the period 2007-2008 in selected seedlings and standard cultivar Meeker. Results showed that all examined seedlings expressed later flowering and maturing time than the standard cultivar. The best results of physical fruit properties had the standard cultivar, whereas for the majority of the chemical fruit characteristics selected seedlings showed much better results. Seedling 5 had the highest soluble solid content (15.3 %), while the highest vitamin C content was recorded in the fruits of seedlings 9 (51.04 mg/100g), 10 (51.92 mg/100g), and 17 (50.16 mg/100g). The highest values of the sensorial fruit quality achieved seedling 17 (18.9).Od preko 100 sejanaca dobijenih slobodnim oprašivanjem žutog klona sorte Miker izdvojeno je 10 sa žutom bojom ploda koji su kolekcionisani na Oglednom dobru 'Radmilovac' Poljoprivrednog Fakulteta, Univerziteta u Beogradu. U periodu 2007- 2008. godina kod izdvojenih sejanaca i standardne sorte Miker, pored fenoloških, ispitivane su fiziČke, hemijske i senzoricke osobine ploda. Rezultati istraživanja su pokazali da su svi ispitivani sejanci kasnije počinjali fenofaze cvetanja i zrenja u odnosu na sortu standard. Najbolje razultate fizičkih osobina ploda ispoljila je sorta standard, dok su prema većini hemijskih osobina izdvojeni sejanci bili daleko bolji od standardne sorte. Sejanac 5 se odlikuje najvišim sadržajem rastvorljive suve materije (15,3 %), a u pogledu sadržaja vitamina C najviše vrednosti su registrovane kod sejanaca 9 (51,04 mg/100g), 10 (51,92 mg/100g) i 17 (50,16 mg/100g). Najvišu senzoricku ocenu kvaliteta ploda imao je sejanac 17 (18,9)