Search

Camelina [Camelina sativa (L.) Crantz] has increased cold, heat, and drought tolerance and decreased susceptibility to diseases and pests than oilseed rape (Brassica napus L.). Because water deficit at sowing leads to unsatisfactory stand establishment due to irregular seed germination and emergence, the aim of this study was to understand the response of camelina germination under osmotic stress and identify critical soil moisture levels for successful establishment. Two spring cultivars, NS Slatka and NS Zlatka, developed at the Institute of Fieldand Vegetable Crops Novi Sad, Serbia, were compared under 9 levels of osmotic stress, ranging from 0 MPa to - 1.6 MPa. Polyethylene glycol was used to obtain the osmotic potential of the solutions. Results showed that the tested cultivars did not decrease germination under mild and medium osmotic stress levels (down to - 0.8 MPa). However, germination significantly decreased in both cultivars under higher levels of osmotic stress, and NS Zlatka was more sensitive. Germination speed significantly increased at - 0.4 MPa. The estimated osmotic potentialsto stop germination were - 1.45 MPa for NS Slatka and - 1.46 MPa for NS Zlatka. Time to 50% germination also showed a significant bi-linear trend in response to osmotic potential, but in the opposite direction than the one observed in germination. Inflection points were recorded at - 0.77 MPa for NS Slatka and - 0.78 MPa for NS Zlatka, thereafter time to 50% of germination rapidly increased. This study confirmed that camelina can withstand increased levels of drought stress at germination, so it could be considered a more suitable option than oilseed rape on marginal land, or environments with irregular precipitation. This is the peer reviewed accepted version of the published article [http://fiver.ifvcns.rs/handle/123456789/2560] that will be available from 30 July 2024

The ongoing climate change, coupled with the transformations of cultivation practices and land use in sole crop production, may cause a significant decline in sunflower yield stability. Considering that the sunflower is the third oilseed in the world oilseed market, with 45 million tons of grain per year, and that it takes the fourth position in the vegetable oil market, the implementation of sustainable growing technology in sunflower production is a necessity. Considering the above, the goal of the research was to analyze and recommend sustainable sunflower production technology in intercropping systems. A four-year trial was conducted in Serbia’s agroecological conditions (45∘34′23.2′′ N 19∘86′18.9′′ E) using a split-plot design. Two oil-type hybrids and one confectionary-type hybrid were intercropped with common vetch, red clover, and alfalfa. Common vetch × sunflower intercropping resulted in the decrease in almost all sunflower traits. Moreover, sunflower × alfalfa intercropping proved to be the most appropriate. The yield of NS Gricko and Rimi PR were statistically on the same level with sole cropping, while alfalfa biomass had better results after alfalfa was intercropped with NS Gricko, as compared to sole cropping. In view of the prevailing belief that yields are more stable in intercropping than in sole cropping, further research is needed in this respect, in addition to further research of the time and method of sowing.

The objective was to assess the effect of chemical desiccation on seed germination and storability in three sunflower female inbred lines and to point at possible indicators for optimal performance time. Desiccation was performed with Diquat (2 l ha-1) applied at 7-day intervals from the end of flowering to harvest maturity. There were 6 treatments and control (untreated). Germination was tested 2 and 21 months after harvest. The highest germination was recorded when the desiccation was performed 35 days after flowering. Results showed that optimal moment for applying chemical desiccation when there is no negative effect on the seed germination is specific for each sunflower genotype. Seeds with a high level of germination (>90%) can be stored for 19 months without significant loss in germination, namely, it was not negatively affected by chemical desiccation. Seed moisture and growing degree-days can be used as reliable indicators for optimal desiccation time. Cilj rada bio je da se ispita uticaj hemijske desikacije na klijavost i čuvanje kvaliteta semena tri inbred linije suncokreta, kao i da se ispitaju mogući indikatori za optimalno vreme izvođenja desikacije. Za desikaciju je korišćen Dikvat (2 l/ha) u intervalima od 7 dana od završetka cvetanja do žetvene zrelosti. Obavljeno je 6 tretmana i kontrola. Klijavost je ispitivana 2 i 21 mesec nakon žetve. Najveća klijavost je zabeležena pri desikaciji 35 dana posle cvetanja. Rezultati pokazuju da je optimalni momenat za izvođenje hemijske desikacije, u kom nema negativnog uticaja na klijavost, specifičan za svaki genotip suncokreta. Seme visokog kvaliteta (>90%) moguće je čuvati 19 meseci bez značajnog smanjenja klijavosti, takođe, kod takvog semena nije bilo ni negativnog uticaja hemijske desikacije. Vlaga semena i sume aktivnih temperatura se mogu koristiti kao pouzdani indikatori optimalnog vremena za izvođenje hemijske desikacije.

Association analysis or linkage disequilibrium mapping is a method for identification of quantitative trait loci (QTLs) in a panel of divergent unrelated individuals based on historical recombinations during a crop’s domestication and selection. It should account for the population structure, which can be the result of adaptation to local conditions or selection, to reduce the possibility of declaring false-positive associations. The aim of this study was to determine potentially significant and consistent associations between markers and agronomic important maize (Zea mays L.) traits using association analysis in a diverse breeding material that can be ultimately implemented in maize selection. To this end, 96 maize inbred lines were evaluated in field trials at three locations in Serbia for eleven agronomic traits and analysed with microsatellite markers. Twenty five microsatellites were used to assess the population structure using Bayesian model-based clustering method and to test the significance of associations between the markers and the traits with general (GLM) and mixed linear (MLM) models. The cluster analysis divided maize inbred lines in four subpopulations, corresponding to the BSSS (Iowa Stiff Stalk Synthetic), LSC (Lancaster Sure Crop), Iodent heterotic groups and exotic and independent germplasm. The models identified associations between twenty five microsatellite markers and eleven agronomic traits, resulting in 133 and 71 associations across the environments for GLM and MLM, respectively. Some of the identified marker-trait associations were significant and consistent in several environments. The associations stable in several environments were identified between the markers bnlg1067 and two flowering traits; nc005 and bnlg434 and plant height, bnlg434 and ear height; bnlg1643 and umc1127 and leaf number, bnlg1360 and ear diameter; umc1019 and umc1506 and number of rows per ear; bnlg2305 and bnlg1451 and ear length, and between bnlg1175 and thousand-kernel weight. The results of this study indicate that these microsatellites could be used in marker-assisted selection of inbred lines, after validation of the marker-trait associations and testing combining abilities of the inbreds during hybrid development. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31073]

The phenomenon of genotype by environment interaction (GEI) represents permanent interest for breeders, geneticists and biometricians with its practical and theoretical aspects. We investigated GEI for grain yield of medium early maturity maize (Zea mays L.) hybrids from the official variety trial network by the Department of Protection and Recognition of Varieties of the Republic of Serbia that includes experimental maize hybrids on eight sites over two years. Environmental variables explained 77.6% and 60.7% of the GEI variation for two consecutive years, respectively. Factorial regression combined with stepwise procedure revealed the model which includes variables precipitation in July (pr7), minimum temperature in May (mnt5), maximum temperature in May (mxt5) and insolation hours in April (sh4), in 2004, and environmental index (EI) and average temperature in September (mt9) in 2005, to be the most explanatory models in the region of Vojvodina (Serbia) in two consecutive years. These results provide a base for further research in GEI and stability analysis, and are a useful tool in characterizing the sub-regions of maize growing area and extending the existing results to new sites. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 451-03-68/2020-14/200032]

The aim of this study was to determine the effect of different seed treatments on germination parameters of three maize genotypes under optimal and suboptimal temperature conditions. Seed was treated with recommended doses of three commercial pesticide formulations: metalaxyl-m 10 g/L + fludioxonil 25 g/L, metalaxyl 20 g/kg + prothioconazole 100 g/kg and thiacloprid 400 g/L. Testing was conducted at 25°C and 15°C. Results of the study indicate that there are differences in response of maize genotypes to applied seed treatments, as well as to a specific treatment at optimal and suboptimal temperatures. Some treatments, depending on the mixing partner and temperature conditions, can affect final germination. In other cases, germination rate can be accelerated or prolonged, but with no effect on final germination. In order to provide fast and uniform emergence under different temperature conditions, further examination of the response of maize genotypes to specific seed treatments would be beneficial. Cilj istraživanja je bio da se utvrdi efekat različitih tretmana na parametre klijanja semena tri hibrida kukuruza na optimalnim i suboptimalnim temperaturama. Seme je tretirano preporučenim dozama komercijalnih pesticidnih formulacija: metalaksil-m 10 g/L+ fludioksonil 25 g/L, metalaksil 20 g/kg + protiokonazol 100 g/kg i tiakloprid 400 g/L. Ispitivanja su vršena u pesku, na 25°C i 15°C. Rezultati ispitivanja ukazuju da postoji razlika u reakciji genotipova kukuruza na primenjene tretmane, kao i na dati tretman u uslovima optimalnih i suboptimalnih temperatura. Neki tretmani, u zavisnosti od preparata koji se mešaju i temperaturnih uslova, mogu uticati na konačnu klijavost. S druge strane, brzina klijanja može biti promenjena, ali bez uticaja na konačnu klijavost. Kako bi se obezbedilo brzo i ujednačeno nicanje u različitim temperaturnim uslovima, dalja analiza reakcije različitih hibrida na date tretmane bi bila od koristi.

Studies on genetic gains in grain yield and other traits may be very useful in providing necessary information to plant breeders about the effectiveness of their breeding programs. The objective of this research was to analyze changes in grain yield, yield stability and morphological characteristics of maize hybrids released in Serbia between 1978 and 2011. Five hybrids, representatives of different breeding periods, were chosen for this study. Field trials were conducted during 2013 and 2014 at three locations in Serbia. The estimated genetic gain per breeding period was 440 kg ha(-1) which corresponds to an approximate annual linear increase in yield of 63 kg ha(-1). Changes in morphological characteristics were presented graphically, compared to the reference value and defined by the third period of breeding. Plant and ear height, kernel row number, number of kernels per row and leaf number were reduced compared to the third breeding period. Kernel depth showed higher variation through periods while in other analyzed traits, major changes in value through the periods were not found. Stability analysis distinguished the hybrids from the sixth and seventh period of breeding as the most stable, whereas the most unstable were representatives of the fifth and third period. Changes in certain morphological traits and yield stability have led to an increase in the genetic potential of the hybrids most probably through the increased tolerance to biotic and abiotic stress factors.

Field trials supposed to enable selection of the most successful genotypes which is critical because of the existence of Genotype by Environment interaction. To assess this interaction we are forced to conduct field trials in several environments and/or years. When we asses grain yield of maize hybrids during the breeding process, it is always based on multi-environment small plot field trial (MESPT). That is why this part of the breeding process is most demanding in terms of technical, financial and labor requirements. In this paper, one possible systematic approach to assessing multi-environment field trials conduction is described. The main goal of the de-scribed approach is to provide the best possible results with the use of reasonable resources. As the results of trials cannot be directly interpreted without previous statistical processing, quality of raw data as input for biometrical (statistical) analysis is essential for obtaining a relevant and objective measure of genotype relative value in terms of productivity and adaptability (reliability) of new advanced maize hybrids. There are many definitions of data quality but data is generally considered high quality if it is fit for intended uses in operations, decision making and planning. The main aim of this paper is to underline the importance of the data cleaning process in MESPT. Svrha poljskih ogleda u oplemenjivanju biljaka je da omogući odabir najuspešnijeg genotipa, što nije uvek jednostavan zadatak prevashodno zbog postojanja interakcija genotipa i spoljašnje sredine. Upravo zbog postojanja interakcija sortni ogledi se izvode u brojnim lokacijama i godi-nama, kako bi se dobila pouzdana procena vrednosti genotipa. U toku oplemenjivačkog procesa, procena prinosa, recimo, hibrida kukuruza, je zasnovana isključivo na rezultatima višelokaci-jskih sortnih mikro ogleda (VSMO). Ovaj deo oplemenjivačkog procesa je stoga najzahtevniji sa tehničkog i finansijskog aspekta ali i sa stanovišta angažovanja obučene radne snage i specifične opreme. U ovom radu prikazan je jedan od mogućih sistematskih pristupa u proceni višelokaci-jskog sortnog ogleda. Glavni cilj predstavljenog pristupa je da obezbedi najbolji mogući rezultat uz angažovanje razumnih resursa. Kako rezultati poljskog ogleda ne mogu biti direktno interpre-tirani bez prethodne obrade podataka, kvalitet ulaznih-sirovih podataka je od krucijalne važno-sti za dobijanje relevantnih i objektivnih procena relativne vrednosti novostvorenih genotipova (hibrida kukuruza) u smislu njihove produktivnosti i stabilnosti. Postoje brojne definicije kvalite-ta podataka, ali se podaci generalno mogu smatrati visoko kvalitetnim ako su odgovarajući za planirane statističke obrade, donošenje odluka i planova. Cilj izloženog rada je da naglasi značaj pročišćavanja/čišćenja podataka pre procesa statističke obrade podataka sortnih mikro ogleda.

Seed priming is a useful technique, applied prior to planting, which partially hydrates the seeds to a point of germination process initiation, followed by drying, which prevents radicle emergence. The objective of this study was to evaluate the effect of various seed priming treatments on germination parameters of maize at different temperatures. Seeds were primed in water (hydropriming) and KNO3 solution (0.1% and 0.5%) by soaking at 25°C for 17h. Germination parameters were tested at 25°C, 15-25°C and 15°C. Seed priming had a positive effect on some seed germination parameters at low and mixed temperature. Treatment with 0.5% KNO3 had the most improving effect. This treatment reduced MGT, T50 and increased GE at low and mixed temperature. Priming showed no positive effect on the final germination. This study showed that seed priming with KNO3 could be used to achieve better seedling establishment at low temperature conditions in maize. Potapanje semena je metod tretmana semena. Primenjuje se neposredno pre setve, pri čemu se seme vlaži do pokretanja procesa klijanja, nakon čega se suši kako bi se sprečilo izbijanje korenka. Cilj ovog ispitivanja bila je procena efekta različitih metoda potapanja semena na parametre klijanja semena kukuruza pri različitim temperaturama. Tretman je vršen potapanjem semena u vodu i rastvore KNO3 (0,1% i 0,5%) pri temperaturi od 25° C u trajanju od 17h. Parametri klijanja praćeni su pri temperaturama 25°C, 15/25°C i 15°C. Potapanje semena je imalo pozitívne efekte na pojedine parametre klijanja pri niskoj i kombinovanoj temperaturi. Najbolji rezultati uočeni su pri potapanju u 0,5% KNO3. Ovaj tretman je smanjio MGT i T50 a povećao GE pri niskoj i kombinovanoj temperaturi. Potapanje semena nije uticalo na klijavost semena. Ovo istraživanje ukazuje na mogućnost primene potapanja u KNO3 u cilju postizanja bržeg nicanja i boljeg sklopa kukuruza pri nižim temperaturama.

Low temperature has a negative effect on germination parameters and early seedling growth. Seed priming is a beneficial pre-sowing treatment that partially hydrates the seeds to the point of germination process initiation, followed by drying which prevents radicle protrusion. The aim of this study was to evaluate the effect of different seed priming treatments on some maize seed vigor and early seedlings growth parameters at different temperature conditions. Seeds were primed in water (hydropriming) and KNO3 solution (0,1% and 0,5%) at 25°C for 17 h. Germination was tested at 25°C, 15/25°C and 15°C. Seed priming treatments had more improving effects on studied seed and seedlings traits under suboptimal (15°C and 15/25°C) than at optimal temperature conditions. Seed priming treatment with 0,5% KNO3 had the most beneficial effects and increased the most of studied parameters under suboptimal conditions. Seed priming with KNO3 could be used to achieve higher seed vigor and seedling growth at suboptimal temperature conditions in maize. Niske temperature imaju negativan uticaj na parametre klijanja i početni porast klijanca. Prajming semena predstavlja tretman kojim se seme delimično hidrira tako da se inicira proces klijanja, a zatim suši kako bi se klijanje zaustavilo pre izbijanja korenka iz semena. Cilj ovog eksperimenta bio je da se ispita uticaj različitih prajming tretmana na vigor i porast klijanca kukuruza u različitim temperaturnim uslovima. Prajming semena izvršen je sa vodom (hidroprajming) i KNO3 rastvorom (0,1% i 0,5%) na temperaturi 25°C u trajanju od 17 h. Seme je naklijavano na 25°C, 15/25°C i 15°C. Pozitivniji efekat prajminga utvrđen je pri suboptimalnim (15°C i 15/25°C) nego pri optimalnim temperaturnim uslovima. Kao najbolji, pokazao se tretman sa rastvorom 0,5% KNO3 uvećavši posmatrane parametre na suboptimalnoj temperaturi. Ovi rezultati ukazuju da je primenom prajminga sa rastvorom KNO3 moguće poboljšati vigor semena i početni porast ponika kukuruza pri suboptimalnim temperaturama, odnosno, obezbediti sigurnije nicanje pri ranim rokovima setve.

2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) is a secondary metabolite in plants that renders defense against phytopatogenic bacteria, fungi, insects and other pest organisms. The biosynthesis of DIMBOA is controlled by nine genes, the first bx1 gene governs the transcription of a key enzyme in DIMBOA biosynthesis. The aim of this study was to genotype maize inbred lines used in breeding programmes for the presence of resistant allele in order to identify the source of biotic stress resistance. The variability of bx1 gene was assessed in a set of 96 diverse inbred lines with a functional microsatellite marker umc1022 located in bx1 gene. Two marker alleles, the length of 91 and 97 bp, were found in the majority of inbred lines, the former being predominant among Lancaster inbred lines and the latter in the BSSS heterotic group. By comparing previous findings on the inbred lines with high level of DIMBOA and resistance with the pedigree information of the maize inbred lines analyzed in this study, we postulated that the allele 91 bp could be associate with DIMBOA accumulation and pest resistance. The DIMBOA quantification and evaluation of pest infestations in field trials are needed to verify our results. 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) je sekundarni metabolit koji omogućava biljkama zaštitu od fitopatogenih bakterija, gljiva, insekata i drugih štetnih organizama. Biosintezu DIMBOA-e regulišu devet gena, od kojih prvi bx1 upravlja transkripcijom ključnog enzima u biosintezi DIMBOA-e. Cilj ovog rada bio je da se među inbred linijama kukuruza iz oplemenjivačkog programa utvrdi prisustvo otpornog alela bx1 gena kako bi se identifikovali izvori otpornosti na biotički stres. Varijabilnost gena bx1 je ocenjena kod 96 genetički divergentnih inbred linija pomoću funkcionalnog mikrosatelitskog markera umc1022 koji se nalazi u genu bx1. Dva alela markera, dužine 91 bp i 97 bp, ustanovljeni su kod većine inbred linija, prvi alel je bio zastupljeniji među Lancaster linijama, dok je drugi alel bio frekventniji u BSSS heterotičnoj grupi. U inbred linijama kod kojih je utvrđen alel 91 bp (Mo17, B97 i H99) u prethodnih istraživanjima je određen visok nivo DIMBOA-e i otpornost prema štetočinama. Shodno tome, pretpostavljamo da je alel 91 bp u vezi sa nakupljanjem DIMBOA-e i sa otpornošću prema biotičkom stresu. Kvantifikacija DIMBOA-e i ocena štete od insekata u poljskim ogledima potrebna je da bi se potvrdili izneti rezultati.

The aim of this study was to investigate field emergence parameters, number of plants that reached reproductive stage and yield of seed lots with different count of abnormal seedlings. In standard germination test these seedlings are discarded from the count of germinated seed, presuming that they will not develop into normal plants. Five lots of hybrid NS 640 with different percentage of abnormal seedlings were tested. Results showed that in favourable environment conditions, large number of abnormal seedlings emerged, reached reproductive stage and participated in yield formation. However, emergence of seed lots with high percentage of abnormal seedlings was longer than for lots with small number of abnormal seedlings. Laboratory germination and germination energy were more correlated with indicators of field emergence rate, while total percentage of germinated seedlings (normal and abnormal) was more correlated with grain yield. However, it can be expected that in adverse environment conditions, abnormal seedlings are less likely to develop into normal plants. Cilj ovog ispitivanja bio je da se kod partija semena sa različitim udelom atipičnih ponika ispitaju parametri brzine klijanja u polju, broj biljaka u reproduktivnoj fazi i prinos. Ovakvi ponici se u standardnom testu klijavosti ne ubrajaju u klijava zrna, jer se pretpostavlja da neće dati normalnu biljku. Testirano je pet partija hibrida NS 640 sa različitim udelom atipičnih ponika. Rezultati su pokazali da je u povoljnim uslovima veliki broj atipičnih klijanaca nikao, dostigao reproduktivnu fazu i učestvovao u formiranju prinosa. Sa druge strane, nicanje partija sa velikim brojem atipičnih klijanaca je bilo usporeno. Laboratorijska klijavost i energija klijanja su bile u većoj korelaciji sa parametrima brzine nicanja, dok je ukupna klijavost (normalni i atipični klijanci) bila u većoj korelaciji sa prinosom. Ipak, u nepovoljnim uslovima spoljašnje sredine, atipični klijanci imaju manje šanse da se razviju u normalnu biljku.

One of the most important phases in commercial maize breeding programs is the assessment of the value of newly-developed progeny by testing in hybrid combinations. In this study, non-parametric stability measures were applied to analyze the genotype × environment interaction and to assess phenotypic stability of two half-sib maize populations, each consisting of 40 genotypes, across 9 variable environments. Non-parametric tests of significance determined the presence of qualitative interaction for grain yield in both observed populations. Results of the stability analysis showed no significant differences between the two progeny groups indicating that the used testers did not bring significant increase in stability in either of the analyzed half-sib populations. Individual genotypes were also compared based on grain yield stability within both progeny groups using the stability parameters Si(1), Si(2), Si(3) and Si(6). Association between the grain yield and stability indices Si(1) and Si(2) of the analyzed genotypes was presented graphically enabling the identification of genotypes which can be recommended for further breeding process as the most promising ones. The correlations between grain yield and stability parameters were tested by Spearman’s rank correlations. Both progeny groups (HS1 and HS2) showed no significant correlations between the grain yield and stability parameters Si(1) and Si(2), but the rank correlations between Si(1) and Si(2) values were very strong and highly significant. Highly significant negative correlations were found between grain yield and stability indices Si(3) and Si(6) in both progeny groups, and very strong and highly significant correlations were found between Si(3) and Si(6) values. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31073: Improvement of maize and sorghum production under stress conditions]

The objectives of this study were to determine the effects of different priming treatments and genotypes on maize germination and early seedling growth traits, as well as to examine the associations among these traits. In addition, the application of genotype by trait biplot methodology in this type of analysis was evaluated. Seed priming treatment was conducted on ten maize inbred lines by soaking seeds in water (hydropriming) or in 0.5% KNO3 solution. Seed was sown in sterile moistened sand and placed at suboptimal (15°C) and optimal temperature (25°C) for seven days. After that, seedling length and seedling weight were measured, final germination, time to 50% emergence and vigour index were calculated. The results showed that seed priming can improve seedling growth traits at both temperatures. There are differences in genotype responses to various seed priming solutions. The observed differences represent useful information for the selection of adapted maize inbred line and adjustment of priming treatment for sowing in different temperature conditions. This study showed that biplot could easily be used for assessing the effect of seed priming, or some other treatment, on seedling growth traits. Moreover, it can be used to understand the associations among the seedling growth traits. Cilj ovog ispitivanja bilo je utvrđivanje uticaja prajming tretmana i genotipa na klijanje i rani porast ponika kukuruza, kao i sagledavanje povezanosti ovih osobina. Takođe, analizirana je mogućnost primene GT biplot metodologije u ovom tipu ispitivanja. Prajming tretman se sastojao od potapanja semena deset inbred linija kukuruza u vodu (hidroprajming) i rastvor KNO3. Seme je zatim posejano u posude sa vlažnim sterilnom peskom i stavljeno na suboptimalnu (15°C) i optimalnu temperaturu (25°C) u trajanju od 7 dana. Nakon toga je izmerena dužina i masa ponika, utvrđena je klijavost i izračunato vreme potrebno za 50% nicanja, kao i vigor indeks. Rezultati su pokazali da početni porast ponika na obe temperature može biti poboljšan prajmingom semena. Primećena je različita reakcija linija na korišćene prajming tretmane. Ove razlike predstavljaju korisnu informaciju za izbor odgovarajuće inbred linije i pogodnog prajming tretmana za setvu u različitim temperaturnim uslovima. Ispitivanje je pokazalo da se biplot analiza može koristiti kao brz vizuelni metod za proučavanje efekta prajminga ili nekog drugog tretmana semena na različite parametre klijanja, nicanja i početnog porasta ponika. Takođe, ova analiza se može koristiti i za sagledavanje veze između ispitivanih osobina.

Grain yield is a result of the combined effects of genotype, environment and their interaction. The importance of the genotype x environment interaction is that it causes different reactions of maize hybrids when they are grown in different environments. This study was performed to analyse discriminativeness, representativeness and relationships of test locations for a grain yield of nine maize hybrids grown at nine locations in a 5 year period 2007-2011 in the South Pannonian Basin, a part of central and south European corn belt. A three-way mixed model revealed the highly significant (P lt 0.01) REML variance components for year x location, year x location x hybrid and residuals. The grain yield was also significantly (P lt 0.05) affected by the year x hybrid and location x hybrid interaction effect. The sites regression (SREG) model was used to determine whether mega-environments exist, and/or whether the test locations used are suitable for maize hybrids zoning. To determine which environmental factors mostly affect the hybrid x location interaction, the partial least squares regression approach was applied. The "which-won-where" pattern of the SREG biplot confirmed a rank change interaction between the locations, indicating the presence of strong and unpredictable rank-change location-by-year interactions. The main characteristic of the grouping pattern was poor repeatability, since most of the locations that made one mega-environment tended to change from year to year. Therefore, it is preferable to develop hybrids with high yielding potentials, wide adaptability and stability, rather than to develop hybrids specially designed for narrow agro-ecological regions.

Maize (Zea mays L.) displays large genetic diversity created during the history of introduction from its Mexican centre of origin to other parts of the world and adaptation to a range of diverse environments. Despite such diversity, maize breeders use only a small portion of the available maize germplasm to develop modern hybrids. Broadening diversity of breeding collections by the introduction of new germplasm, as a source of favourable traits, requires its characterisation and classification of new germplasm into heterotic groups. The aim of this study was to estimate genetic diversity of maize breeding material from the Institute of Field and Vegetable Crops in Serbia, including previously uncharacterised inbred lines, elite lines with known pedigrees and historically important inbred lines. Microsatellite-based cluster analysis and principal coordinate analysis separated 96 inbred lines into six clusters, Iowa Stiff Stalk Synthetic (BSSS), Lancaster Sure Crop (LSC), Iodent (IDT) heterotic group, a cluster with unrelated independent inbreds and two clusters of miscellaneous germplasm crossed with inbreds of BSSS and Lancaster background. The microsatellites umc1035, bnlg666, dupssr23, umc1083 and dupssr10 contributed most to the differentiation between the groups. The largest values of molecular diversity parameters were detected in the BSSS group, following by the Lancaster and then the other groups. An analysis of variance showed that almost all traits significantly varied among the groups and between the years. The investigated lines demonstrated sufficient variation in most of the analysed phenotypic traits, proving suitable for further genetic studies. A principal component analysis based on agronomic traits differentiated inbred lines from the BSSS and Lancaster pools, but failed to separate the other groups. The characterisation and classification of genetic resources using microsatellite markers may assist hybrid breeding by efficient exploitation of heterotic patterns.

Two main questions in programs introgressing exotic maize germplasm into temperate materials are the choice of available exotic sources to work with, and the proportion of exotic germplasm that should be incorporated into adapted germplasm. The objective of this study was to compare effects of different proportions of tropical maize inbred line NC298 in hybrids male parent on grain yield and grain moisture content, using method of orthogonal polynomials. Methods of direct crosses and backcrosses were used to form four hybrid groups (six hybrids each) containing 0, 25, 50 and 75 percent of tropical exotic germplasm, respectively, by their male parent (or one half of mentioned proportions in the corresponding hybrids). The linear components of the germplasm proportions sum of squares, were significant (p lt 0.01) for both grain yield and moisture content and the cubic effect (p lt 0.05) for grain yield only. Results in this study clearly suggested backcross foundation populations with an adapted line to be appropriate selection sources for both grain yield and grain moisture content. Inkorporacija egzotične germplazme u genetički materijal umerenog klimata nameće dva osnovna pitanja: izbor i proporciju odgovarajućih egzotičnih izvora. Cilj ovog istraživanja je bio poređenje efekata različitog udela tropske linije kukuruza NC298 u očinskoj komponenti hibrida, na prinos zrna i udeo vode u zrnu, primenom metode ortogonalnih polinoma. Metodom direktnih i povratnih ukrštanja dobijene su četiri grupe hibrida (po šest hibrida u svakoj) koje su sadržale 0, 25, 50 i 75 procenata tropske germplazme, u njihovoj očinskoj komponenti (ili jednu polovinu pomenutih procenata u odgovarajućim hibridima). Sume kvadrata linearne komponente, bile su značajne (p lt 0.01) za prinos zrna i za udeo vode u zrnu, dok su sume kvadrata kubnog efekata bile značajne (p lt 0.05) samo za prinos zrna. Rezultati ovih istraživanja jasno ukazuju da su početne populacije nastale povratnim ukrštanjem sa adaptiranom linijom pogodan izvor za selekciju na prinos zrna i udeo vode u zrnu.

GGE biplot analysis is a method used to identify mega-environments (i.e grouping, division of locations, which are examined in a joint mega-environment), evaluate the genotypes within these mega-environments and select the most discriminating and the most representative locations within a single mega-environment. This paper analyses twenty hybrids at five locations in 2006 and 2007. For the first year, mega-environment analysis showed a greater similarity between locations Rimski Šančevi, Pančevo and Srbobran classifying them into one group (the potential mega-environment), whereas Sombor and Sremska Mitrovica were classified into another group. In 2007 grouping was different from the previous in that Rimski Šančevi and Sombor comprised one mega-environment, whereas Sremska Mitrovica and Pančevo comprised the other, while Srbobran was separated from both groups. Discrepancies in formation of the mega-environments can be explained by different climatic conditions in two research years. This was confirmed by analyzing the ideal environment where the discrepancies between those two years are also reported. The results in this study suggest that more reliable data on the mega-environments formation should be sought in multi-year studies of the certain genotypes in a number of locations. Multilokacijski ogledi za prinos zrna izvode se svake godine kako bi se ocenila reakcija hibrida kukuruza na različite agroekološke uslove. Osnovni problem ovog načina ispitivanja hibrida jeste prisustvo interakcije genotip-spoljna sredina. Uzimajući u obzir interakciju, GGE biplot analiza pruža vizuelni prikaz ponašanja hibrida u različitim sredinama. Dvadeset hibrida kukuruza je ispitivano u toku 2006. i 2007. na pet lokaliteta po godini. Rezultati su predstavljeni preko GGE biplotova u cilju grupisanja sredina u tzv. megasredine i izdvajanja idealne sredine. Značaj izdvajanja megasredine ogleda se u odsustvu unakrsne interakcije koja remeti njihov rang, pa se hibridi mogu odabrati na osnovu prosečnih vrednosti određene osobine. Određivanje tzv. idealne sredine može biti od velikog značaja za izbor najreprezentativnijeg lokaliteta za testiranje, koji takođe ima i najveću moć diskriminacije hibrida.

Association analysis is a relatively novel approach in quantitative traits studies that allows high resolution mapping and time efficient and direct application on breeding material. Since the markers, which are close to the quantitative trait loci stable across environments and genetic BACKGROUND: s, may be valuable for marker assisted selection, we chose microsatellite markers previously linked to traits of interest in various mapping studies. A set of 36 microsatellite markers positioned near important maize (Zea mays L.) agronomic loci was used to evaluate genetic diversity and determine population structure. To verify the associations between the markers and traits, a panel of diverse maize inbred lines was genotyped with microsatellites and phenotyped for flowering time, yield and yield components. A relatively high level of polymorphism detected in number of alleles per locus (8.2), average polymorphic information content value (0.64), and average gene diversity (0.684) lines showed the analyzed panel of maize inbred contained significant genetic diversity and was suitable for association mapping. The population structure estimated by model-based clustering method grouped maize inbred lines into three clusters. The association analysis using the general linear and mixed linear models determined significant correlations between several agronomic traits and three microsatellites on chromosomes 3, 5, and 8, namely umc1025, bnlg1237, and bnlg162 consistent across the environments, explaining from 4.7% to 18.2% of total phenotypic variations. The results suggest that the chromosome regions containing quantitative trait loci (QTLs) associated with multiple yield-related traits consistently across environments are potentially important targets for selection.

National audience; Traditional landraces adapted to local conditions harbour alleles for traits of interest and may be of valuable contribution in enhancing the stability of maize production under increasing challenges of climatic changes. It is therefore of great importance to preserve and assess local maize populations as a potential source of favourable agronomic traits. As a part of the bilateral project DIVERZEATY between Serbia and France (2014-2015), ten local landraces and ten inbred lines, derived from local landraces of the Maize Research Institute Zemun Polje gene bank and the Institute of Field and Vegetable Crops collection, were characterised at a pilot scale. The analysed accessions from diverse regions of former SFR Yugoslavia were genotyped with MaizeSNP50 BeadChip and allelic frequencies for landraces were estimated from the bulked DNA. Principal coordinate analyses showed the genotypes cover a range of diversity. Four local dent landraces grouped with Corn Belt populations, four populations grouped closely to European OPVs and Northern flints, one landrace with Italian flints and one was grouped in the Mexican cluster within the first two axes and with Corn Belt on the third and fourth coordinates. Two inbred lines, developed from the Montenegrin landraces, and one inbred line, derived from a Slovenian landrace, grouped with Northern flint lines, whereas the others clustered with Stiff Stalk ones. The landraces and lines fit well to historical data about their origin and introduction of maize in the region.

Within maize breeding program at the Institute of Field and Vegetable Crops Novi Sad, Serbia, there have been seven distinct breeding cycles spanning from the mid-1960s. Each cycle is characterised by introduction of new hybrids with higher genetic yield potential. Breeding cycles were defined based on the period of hybrid introduction into production and the growing areas. In this study we analysed grain yield and moisture percentage in grain of five maize hybrids, namely NS 606, NS 640, NS 6010, NS 6030 and NS 6140, which are the representatives of the third, fourth, fifth, sixth and seventh breeding cycles. Seed of hybrids which are representatives of the first and second breeding cycles, namely NS 802 and NSSC 70, could not be produced because their parent inbred lines have lost their authenticity. According to the results of the combined ANOVA, significant differences (P lt 0,001) in grain yield were found among hybrids representatives of various breeding cycles and various environments, while the interaction cycle/ environment was found to be insignificant. A linear increase of yield by 0.44 t ha-1 (expressed by coefficient of linear regression) was found between individual breeding cycles. Since one breeding cycle lasts for approximately 7 years, average grain yield increase in maize from the third to the seventh breeding cycle was found to be 63 kg ha-1 per year. U programu oplemenjivanja kukuruza u Institutu za ratarstvo i povrtarstvo Novi Sad se može izdvojiti sedam ciklusa selekcije od sredine šesdesetih godina prošlog veka do danas. Svaki ciklus se karakteriše uvođenjem novih hibrida sa višim genetičkim potencijalom rodnosti. Kao kriterijum za definisanje ciklusa selekcije je korišten period uvođenja hibrida u proizvodnju i njegova zastupljenost. U ovom radu smo ispitivali prinos zrna i procenat vode u zrnu u berbi kod pet hibrida kukuruza: NS 606, NS 640, NS 6010, NS 6030 i NS 6140, glavnih predstavnika trećeg, četvrtog, petog, šestog i sedmog ciklusa selekcije. Seme hibrida NS 802 i NSSC 70 koji su glavni predstavnici prvog i drugog ciklusa selekcije nismo mogli proizvesti pošto su roditeljske inbred linije izgubile autentičnost. Na osnovu rezultata kombinovane ANOVE, signifikantne razlike (P lt 0.001) u prinosu zrna ustanovljene su između hibrida predstavnika pojedinih ciklusa selekcije i između sredina, dok je interakcija ciklus/spoljašnja sredina bila nesignifikantna. Između pojedinih ciklusa selekcije je ustanovljeno linearno povećanje prinosa od 0,44 t ha-1 ciklusu-1 (izraženo koeficijentom linearne regresije). Obzirom da jedan ciklus selekcije traje približno 7 godina, prosečno povećanje prinosa zrna kukuruza od trećeg do sedmog ciklusa selekcije iznosi 63 kg ha-1 godini-1.

The goal of this study was to determine correlations between grain yield and other morphological and agronomical traits in two groups of maize half-sib (HS) progenies. Progenies were obtained by crossing every S1 family with two unrelated inbred lines as testers, NS732 and NS27. Field trials with incomplete block design, with replicates within set were conducted in 2008 and 2009 at four locations. The following traits were observed: grain yield, ear length, kernel row number, kernel number per row, 1000-kernel weight, plant height, ear height, number of leaves above ear and grain moisture. Significant moderate strong negative correlation between grain yield and ear length was determined in HS1 progeny. High significant correlations occurred among plant and ear height in both HS and between plant height and number of leaves. Observed differences in levels of correlation imply significant influence of tester in each group on HS progeny. Cilj ovog istraživanja je bilo određivanje korelacija između prinosa zrna i drugih morfoloških i agronomskih osobina dve polusrodničke grupe potomstava (HS) kukuruza. Nasumično odabrane biljke iz svake S1 familije su ukrštene sa testerima NS732 i NS27. Dve polusrodničke grupe potomstava su formirane tako da je svaka S1 familija ukrštena sa oba testera. Poljski ogledi sa nepotpunim blok dizajnom sa tri ponavljanja po setu su posejana 2008. i 2009. na četiri lokaliteta. Praćene su sledeće osobine: prinos zrna, dužina klipa, broj redova zrna, broj zrna po redu, masa 1000 zrna, visina biljke, visina klipa, broj listova iznad klipa i vlaga zrna. Kod HS1 potomstva je uočena srednje jaka negativna korelacija između prinosa zrna i dužine klipa. Takođe, visina biljke i visina klipa su bile u jakoj vezi kod oba HS potomstva. Dobijene razlike u stepenu korelacije ukazuju na značajan uticaj testera u svakoj grupi HS potomstava.

The interpretation of new varieties performance is disturbed under the influence of genotype-by-environment interaction. Among several methods used for understanding this effect, one of the most frequently used methods is Additive Main Effects and Multiplicative Interaction (AMMI) analysis. In this study we used AMMI method with the aim to estimate the genotype - environment interaction of 14 barley genotypes, and to identify barley genotypes that have high and stable performance in different environments. The trials were conducted during 11 growing seasons (1995/96 - 2005/06), arranged in a randomized complete block (RCB) design with four replications in location Rimski Šančevi. The results showed that the influence of environment (seasons), genotypes and their interaction on barley grain yield were significant (p < 0.01). Based on AMMI method, two-rowed variety Novosadski 317 and the six-rowed variety Novosadski 331 can be distinguished due their high and stable yields. [Projekat Ministarstva nauke Republike Srbije, br. TR-31066]

One of the final stages in the process of maize breeding is testing the potential hybrids in pre-registration multi-location trials. The aim of this study was to evaluate six locations (Pančevo, Sremska Mitrovica, Ruma, Srbobran, Rimski Šančevi and Sombor) in the northern Serbia for testing yields of maize seed hybrid by GGE (Genotype and Genotype by Environment Interaction) biplot method in the period from 2007 to 2011. This study comprised 24 maize hybrids tested across 6 environments. Different sets of hybrid were used every year. Hybrids served as 'a random' factor for the evaluation of locations. The ANOVA indicated significant effects of genotypes (G) and environments (E) every year, while their interaction (GE) was significant in 2007, 2009 and 2011. On average, the SO location provided the smallest amount of information and therefore can be excluded from further trials and analysis. The sites SM and RU were the most similar locations and only one of these two locations should be included in further trials. The location RŠ presented the smallest repeatability. For analysis that is more detailed it is necessary to include more locations in trials and analysis. Jedna od krajnjih faza u procesu oplemenjivanja kukuruza je testiranje potencijalnih hibrida u više-lokacijskim pretkomisijskim ogledima. Cilj ovog istraživanja bila je procena šest lokaliteta (Pančevo, Sremska Mitrovica, Ruma, Srbobran, Rimski Šančevi i Sombor) u severnoj Srbiji za testiranje prinosa zrna hibrida kukuruza GGE biplot metodom u periodu od 2007 do 2011. god. Ovo istraživanje je obuhvatilo 24 hibrida kukuruza testirana na šest lokaliteta. Različiti setovi hibrida su korišćeni svake godine. Hibridi su služili kao 'random' faktor za procenu test lokaliteta. ANOVA test je pokazao značajne efekte genotipa (G) i životne sredine (E) svake godine, dok je njihova interakcija (GE) bila značajna u 2007, 2009. i 2011. U proseku, lokalitet SO je pružio najmanje informacija, pa se stoga može isključiti iz daljih ogleda i analiza. Lokaliteti SM i RU su bili najsličniji, tako da samo jedan od njih treba da se uključi u dalja testiranja. Lokalitet RŠ je imao najmanju ponovljivost. Takođe trebalo bi uključiti, druge, do sada nekorišćene lokalitete u budućim višelokacijskim ogledima.

Genetic markers, from morphological to molecular, in function with early Heterosis is a prerequisite for the successful commercial maize production. It does not appear in any cross of two inbred lines, and therefore, the determination of combining abilities of parental lines is essential. The most commonly used method for determining combining abilities is diallel analysis. Besides conventional methods for diallel analysis, a new biplot approach has been sugested. In this paper, we studied the combining ability for grain yield in a set of genotypes obtained by diallel crossing system of six inbred lines. Both, the Griffing's conventional method and the biplot approach have been used for diallel analysis. Comparing the GCA values from biplot analysis and Griffing's method, similar results can be observed, with the exception of NS L 1051 and NS L 1000 whose ranks are interchanged. Biplot analysis enables the SCA estimation of parent inbred, and the highest SCA has inbred B73D. Biplot analysis also allows the estimation of the best crosses. Inbred B73D shows the best results when crossed with testers Mo17Ht, NS L 1051 and N152, inbred N152 combines best with testers NS L 1001 and NS L 1000, whereas the cross of inbred NS L 1051 with tester B73D results with the highest grain yield per plant in comparison with other testers. Određivanje kombinacionih sposobnosti roditeljskih inbred linija, radi iskorištavanja heterozisa, je od suštinske važnosti. Najčešće korišćen metod je dialelna analiza. Pored konvencionalnih metoda dialelne analize za procenu kombinacionih sposobnosti, u poslednje vreme prisutan je i novi pristup analize kombinacionih sposobnosti. U ovom radu smo proučavali kombinacione sposobnosti za prinos zrna u setu genotipova dobijenih dialelnim sistemom ukrštanja šest linija. Pored primene konvencionalne metode analize po Griffingu, korišten je i biplot pristup za sagledavanje podataka. Upoređujući vrednosti OKS dobijenih biplot analizom i primenom Griffing-ovog metoda, dobijeni su slični rezultati, sa izuzetkom NS L 1051 i NS L 1000 čiji su rangovi zamenjeni. Biplot analiza omogućava i procenu PKS samih roditeljskih linija. Najveća vrednost PKS zapažena je kod linije B73D, a zatim slede: NS L 1051, NS L 1001, Mo17Ht, N152 i NS L 1000. Biplot analiza takođe omogućava i procenu najboljih ukrštanja. Inbred linija B73D pokazala je najbolje rezultate u ukrštanju sa linijama Mo17Ht, NS L 1051 i N152, N152 sa NS L 1001 i NS L 1000, dok se linija NS L 1051 najbolje kombinuje sa testerom B73D.