EFFECTS OF EXPERIMENTAL MODEL OF EXPLOSIVE STRENGTH IN REGULAR PHYSICAL EDUCATION CLASSES

.The study was conducted with the goal to determine the effects of explosive strength training on the transformation of motor skills and functional abilities during regular physical education classes, among students of primary schools. The sample of examinees consisted of 64 pupils from Niš, 14 years old. Experimental group comprised of 32 examinees, selected for the training of experimental model of explosive strength in the main part of regular physical education classes, three times per week, in duration of 45 minutes, for the period of eight weeks. One half of these classes was dedicated to regular PE curriculum, while the other half to an experimental program of explosive strength, in duration of eight weeks. Control group also comprised of 32 examinees, who attended regular physical education classes, three times per week in duration of 45 minutes, for the period of eight weeks. Following motor skill were assessed: coordination (two tests), sprint speed (two tests), repetitive strength (two tests), and explosive strength (two tests). Following functional abilities were assessed: pulse frequency after physical activity, Margaria test, and vital lung capacity. For processing of data, variance and covariance analysis were applied. Study results showed that experimental group of examinees achieved better results in motor skills and functional abilities, as well as that there were statistically significant effects at the final testin

MOTOR SKILLS IN FOURTH GRADE PRIMARY SCHOOL STUDENTS

The authors of this paper, which is a part of a more extensive research, provide an overview of anthropometric characteristics and motor skills in fourth-grade primary school students in Vranje and differences in these between boys and girls. The anthropometric characteristics included in the measurements were body height (Tv) and body weight (Tt), while the motor skills measured were the explosive leg power, explosive torso and shoulder power, speed, static (isometric) arm and shoulder strength, and flexibility (mobility).Body height was measured by a height meter, body weight by a weight scale, explosive leg power by a standing long jump (Sudm), explosive torso and shoulder power was measured by throwing a 2 kg medicine ball (Bm), speed was measured by a 30 m run from a high start (Tvs), static (isometric) arm and shoulder strength with pull-up endurance up to 120 seconds (Iuz) and flexibility (mobility) with standing hamstring stretch (Dpk). This research included 500 participants, fourth-grade primary school students in Vranje, both boys and girls. Statistical analysis provided us with descriptive data as well as with the differences between boys and girls in anthropometric and motor skill variables which were calculated using the t-test. The research results tell us that all the statistically significant differences are in favour of the boys. The same results that this research has provided can serve as a basis for further diagnostics efforts and  planning of physical education lessons. These findings have also shown us that it is necessary to identify reliable measuring instruments for monitoring and tracking the state and changes in the anthropometric characteristics of younger school age children.

Comparison of similarity coefficients used for cluster analysis based on SSR markers in sister line wheat cultivars

The objective of this study was to compared fourteen different similarity coefficients and their influence in sister line wheat cultivars clustering. Seventeen sister cultivars developed from two crosses were used and fingerprinted with 19 wheat microsatellite markers. Comparisons among the similarity coefficients were made using the Sperman correlation analysis, dendogram evaluation (visual inspection and consensus fork index CIc), projection efficiency in a two-dimensional space, and groups formed by the Tocher optimization procedure. The Sperman correlation coefficients among the fourteen similarity coefficients were all high showing a strong association between them. The correlation coefficient between Dice and Kulczinski and Ochiai I as well as between Hamann and Simple matching and between Kulczinski and Ochiai I was equal to 1. Although visual estimation of the dendograms shows almost identical clustering structures, CIc indexes indicate that all coefficients are not identical

Primena GIS-a u analizi intenziteta erozije u slivu reke Vlasine

This paper analyses the state of erosion intensity in the Vlasina River Basin, the right tributary of the Južna Morava River. To determine the erosion intensity (Z) and sediment production, the Gavrilović method was used, in combination with the bare-soil index (BSI), with the application of geographic information systems (GIS) and multispectral satellite imagery. An erosion coefficient of 0.31 has been identified in the territory of the Vlasina River Basin, which has an area of 1,061.72 km². The prominent vertical fragmentation of the relief, large amount of precipitation in the source parts, density of the river network (1.65 km/km 2), which is above the average river network density in Serbia, as well as inadequate land exploitation, are the main reasons why it is necessary to monitor the erosion intensity in the Vlasina River Basin. The annual production of the sediment is 462,496.30 m³, while the value of specific sediment production is 435,47 m³/km²/year. This study represents the attempt to apply modern technologies to d1etermine the intensity of erosion in the Vlasina River Basin, and the results obtained could be used for more adequate management of land and water resources, sustainable planning of the forest ecosystems and environmental protection.U ovom radu analizirano je stanje intenziteta erozije u slivu reke Vlasine, desne pritoke Južne Morave. Za određivanje intenziteta erozije (Z) i produkcije nanosa korišćen je metod Gavrilovića u kombinaciji sa indeksom ogolićenosti zemljišta (BSI), primenom geografskih informacionih sistema (GIS) i multispektralnih satelitskih snimaka. Na teritoriji sliva Vlasine koji ima površinu od 1.061,72 km2, identifikovan je koeficijent erozije od 0,31. Izražena vertikalna raščlanjenost reljefa, velika količina padavina u izvorišnim delovima, gustina rečne mreže (1,65 km/km2) koja je iznad prosečne gustine rečne mreže u Srbiji, kao i neadekvatan način korišćenja zemljišta predstavljaju glavne razloge zbog kojih je potrebno pratiti intenzitet erozije u slivu Vlasine. Godišnja produkcija nanosa iznosi 462.496,30 m3, dok je vrednost specifične produkcije nanosa 435,47 m3/km2/god. Ovaj rad predstavlja pokušaj primene savremenih tehnologija za određivanje intenziteta erozije u slivu Vlasine, a dobijeni rezultati se mogu koristiti za adekvatnije upravljanje zemljišnim i vodnim resursima, održivo planiranje šumskih ekosistema i zaštitu životne sredine

Varijacija NDVI vrednosti i veza sa prinosom kod ozimog dvoredog ječma

The simple methods used for indirect biomass determination are recognized as potentially important tools for crop growth prediction. The normalized difference vegetation index (NDVI) is widely used for assessing crop biomass, yield, photosynthesis, and nitrogen management. Aims of this study were to determine the variation in NDVI values and relationship of the NDVI with the most significant agronomic properties in the elite genotypes of two-rowed winter barley. The experiment included elite two-rowed winter barley genotypes and was carried out in two growing seasons. NDVI were measured at mid-anthesis, while grain yield and grain yield components were determined from combine harvested samples at maturity. Results from this study showed that the influence of genotype was mainly responsible for variation in most studied traits. Grain yield of two-rowed barley cultivars was more related to high grain number per unit area than to grain weight. NDVI values at anthesis in both growing seasons were positively associated with grain yield (R2 = 0.444 and R2 = 0.386), grain number (R2 = 0.387 and R2 = 0.507) and plant height (R2 = 0.352 and R2 = 0.364), while relationship with grain weight was not significant. Significant genotypic variation for NDVI values and the presence of significant positive relationship with grain yield and grain number indicated that NDVI measurement at anthesis could be efficiently used for indirect identification of productive two-rowed winter barley genotypes.Jednostavne analize koje se koriste za indirektno određivanje biomase predstavljaju potencijalno značajne metode za predviđanje rasta useva. Normalizovani diferencijalni vegetacioni indeks (NDVI) se često upotrebljava za ocenu biomase, prinosa i drugih osobina. Cilj ovog istraživanja je bilo utvrđivanje varijacije u NDVI vrednostima i veze sa najznačajnijim agronomskim osobinama kod elitnih genotipova dvoredog ozimog ječma. Ogled sa elitnim genotipovima ozimog ječma je izveden tokom dve sezone. Očitavanje NDVI vrednosti je izvršeno tokom sredine cvetanje, dok su prinos zrna i komponente prinosa određene iz uzorka nakon kombajniranja u punoj zrelosti. Rezultati ovog istraživanja ukazuju da je uticaj genotipa predstavaljao osnovni izvor varijacije kod većine proučavanih osobina. Prinos zrna kod genotipova ozimog dvoredog ječma je bio u većoj vezi sa brojem zrna po jedinici površine u odnosu na masu zrna. NDVI vrednosti u cvetanju u obe sezone su bile u pozitivnoj vezi sa prinosom, brojem zrna i visinom biljaka, dok veza sa masom zrna nije bila značajna. Značajna genotipska varijacija za NDVI vrednosti i značajna pozitivna povezanost sa prinosom zrna i brojem zrna ukazuje da vrednosti NDVI u cvetanju mogu da se efikasno koriste za indirektnu identifikaciju produktivnih genotipova ozimog dvoredog ječma

Kako neznatna modifikacija metode probnog pečenja kojom se ocenjujuje pecivost i mešavinska vrednost sorti pšenice utiče na najvažnije osobine hleba (zapreminu hleba i VBS)

The aim of the study was to examine how a slight modification of the standard bread-making procedure for the evaluation of wheat cultivars affects bread making properties of different quality samples, without α-amylase activity. For that purpose, two wheat cultivars of different quality (Zvezdana and NS 40S) were examined from four different localities without diastatic activity. Standard physicochemical and rheological parameters for wheat cultivars evaluation were analysed on the eight samples. Also, bread made from flour of these samples was produced according to the standard bread-making procedure for evaluation wheat cultivars and with addition of sugar and malt according to a modified procedure. The results showed that a slight modification of the standard breadmaking procedure can affect the most important properties of bread (bread volume and bread crumb quality). The average values of both parameters were statistically higher. Additionally, statistical analyses showed that bread volume of both cultivars of differing quality was statistically higher, whereas only Zvezdana had statistically higher bread crumb quality.Clij ovog istraživanja je bio da se ispita kako neznatna modifikacija standardne metode probnog pečenja kojom se ocenjuje pecivost i mešavinska vrednost sorti pšenice utiče na osobine hleba sorti pšenice različitog kvaliteta, u kojima nije izražena αamilazna aktivnosti. Standardna metoda probnog pečenja kojom se ispituje pecivost i mešavinska vrednost sorti pšenice u recepturi ne sadrži sredstva za povećavanje amilazne aktivnosti što može veoma uticati na ocenu hleba i vrednost zapremine hleba kada su u uzorcima sorti pšenice utvrđene visoke vrednosti broja padanja i maksimalnog viskoziteta. Zbog toga su odabrani uzorci dve sorte pšenice različitog kvaliteta (Zvezdana i NS 40 S) sa četiri lokaliteta u kojima je utvrđena niska amilazna aktivnost. U ovih osam uzoraka su ispitani standardni fizičkohemijski i reološki pokazatelji za ocenu tehnološkog kvaliteta sorti. Hleb od brašna ovih sorti je proizveden prema standardnoj metodi probnog pečenja kojom se ocenjuje pecivost i mešavinska vrednost sorti pšenice i sa dodatkom šećera i slada prema modifikovanom postupku. Rezultati su pokazali da neznatna modifikacija standardnog postupka probnog pečenja kojom se ocenjuje pecivost i mešavinska vrednost sorti pšenice može uticati na najvažnije osobine hleba (zapreminu hleba i VBS). Prosečne vrednosti oba ova pokazatelja bile su statistički više. Statistička analiza je dodatno pokazala da zapremina hleba obe sorte je statistički značajno visa, ali da samo sorta zvezdana ima statistički značajno višu vrednost VBS-a

Changes in physiological and quality traits related to the breeding progress

Constant grain yield improvement is the main objective of breeding programs worldwide. During the past century, grain yield potential of main European cereal crops, maize, barley and wheat has been continuously improved as the result of changes in production technology and development of modern high-yielding cultivars. Information about changes in physiological and quality traits and their contribution to the grain yield improvement are important for further adaptation of cereal breeding strategies. Growing conditions in the Pannonian Plain are negatively influenced by climate changes, limiting high and stable grain yield production of different main cereal crops. Therefore, constant development of new cultivars and hybrids with stable and higher grain yield is one of the most important strategies to mitigate the negative influence of changing climate, securing the higher grain yield production. During the past century, the grain yield of different cereal crops significantly increased at the rate of approximately 50 kg ha-1 in maize, winter wheat and winter barley under conditions of the Pannonian Plain

The variation of agronomic traits associated with breeding progress in winter barley cultivars

In the 20th century, grain yield of winter barley has increased due to advances in both breeding and crop management practices. Knowledge about the association of agronomic traits with genetic gains in yield potential is necessary to improve future breeding programs. Therefore, we studied the variation in grain yield, spike length, heading date, thousand grain weight, hectolitre mass and plant height of two-rowed winter barley cultivars that were released between 1977 and 2010, in a 2-year field trial. Our results showed that most of the analyzed traits were significantly affected by the cultivar, year and cultivar-by-year interaction. The present study showed that grain yield was positively correlated with the year of release. The average rate of grain yield increase in Serbia was 46 kg ha(-1) per year. Further, grain yield was negatively correlated with plant height and heading date. Plant height and hectolitre mass of modern cultivars showed a significant declining trend, from the oldest to the newest cultivars. An improved understanding of the changes in agronomic traits over the last 40 years of barley breeding will help to identify targets for further breeding progress and improve the genetic potential of barley

Atlas - nova sorta stočnog ječma palidum tipa klasa

This paper presents features of a new variety of winter six-rowed barley Atlas created at Institute of Field and Vegetable Crops Novi Sad, which was released in Serbia in 2005 and in Bosnia and Hercegovina in 2009. It belongs to a group of early varieties. In Serbian Varietal Release Committee trials the yield of variety Atlas was 347 kg/ha higher than the standard, while heading was three days earlier. This variety has moderately large grains and 1000-kernel weight of 35-37 grams, test weight of 72-75 kg/hl and a high protein content of over 14% cm. Variety Atlas would be sown at the beginning of October with a planting rate of approximately 350 viable seeds per square meter. It is recommended to be grown on moderately fertile soil, since its performance is weaker on soils of lower quality. .U radu su prikazane osobine nove sorte ozimog šestoredog ječma Atlas, koja je stvorena u Institutu za ratarstvo i povrtarstvo Novi Sad, registrovana u Srbiji 2005, a u Bosni i Hercegovini 2009. godine. Spada u grupu ranih sorti. U ogledima komisije za priznavanje sorti Republike Srbije prinos sorte Atlas bio je veći 347 kg/ha u odnosu na standard a klasanje tri dana ranije. Sorta ima zrno umerene krupnoće, sa masom hiljadu zrna od 35-37 grama, hektolitarsku masu 72-75 kg/hl i visok sadržaj proteina, preko 14% cm. Setvu sorte Atlas treba obaviti početkom oktobra, sa setvenom normom oko 350 klijavih zrna/m2. Na lošijim zemljištima daje slabe rezultate i preporučuje se za gajenje na zemljištima umerene plodnosti.

Povezanost između prinosa zrna i agronomskih osobina ozimog pivskog ječma

Grain yield is one of the most important and complex traits in cereal breeding and depends upon a combination of different plant traits. Therefore, an effective breeding program requires a proper understanding of the relationships between grain yield and agronomic traits. The objectives of this study were the evaluation of two-rowed winter malting barley genotypes and the perceiving of relationships among grain yield and their agronomic and quality traits. The trials with 19 two-rowed winter malting barley genotypes were conducted during three years. The relationships among plant lodging, height, thousand kernel weight, hectolitre mass, grain protein content and grain yield, were studied by PCA biplot analysis. The results showed that the influence of year, genotype and genotype by year interaction on barley grain yield were significant. Further, results indicate that two-rowed winter malting barley grain yield can be improved by selecting plants of average plant height with thousand kernel weight above 41.0 g and grain protein content of about 11.0 g 100-1g dm.Prinos zrna je jedna je od najznačajnijih i najsloženijih osobina u procesu oplemenjivanja strnih žita koja zavisi od većeg broja svojstava biljaka. Uspešni programi oplemenjivanja zahtevaju pravilno poznavanje povezanosti između prinosa i različitih agronomskih osobina. Cilj ovog ispitivanja je bila ocena genotipova ozimog pivskog ječma i asocijacija između pojedinih agronomskih osobina i prinosa zrna. PCA biplot analiza je korištena za proučavanja povezanosti između poleganja, visine, mase hiljadu zrna, hektolitarske mase, sadržaja proteina i prinosa zrna kod 19 genotipova ječma. Rezultati su pokazali značajan uticaj godine, genotipa i interakcije genotip-godina na ispitivane osobine ječma. Takođe, utvrđeno je da se prinos zrna ozimog pivskog ječma može unaprediti odabirom biljaka optimizovane visine otpornih na poleganje sa višom masom hiljadu zrna (preko 41,0 g) i nižim sadržajem proteina u zrna (oko 11,0 g 100-1g dm)