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Plasmids are autonomous episomally replicating genetic elements, which carry backbone genes important for the replication and maintenance within their host, and accessory genes that might confer an advantage to their host under specific selective pressure in its ecological niche. The genome of dairy isolate L. lactis subsp. lactis bv. diacetylactis S50 was sequenced using the PacBio SMRT Cell Seq-RSII platform and revealed to possess one of the largest plasmidomes among L. lactis strains studied so far, harboring six plasmids: pS6 (5553 bp), pS7a (7308 bp), pS7b (7266 bp), pS19 (19,027 bp), pS74 (74,256 bp) and pS127 (127,002 bp) in total representing 8.9% of genome size (240,412 bp). Based on predicted plasmid replication proteins and origins it appears that all six plasmids replicate via the theta-type mechanism. The two the largest plasmids (pS74 and pS127), carry a number of genes known to be important for growth and survival in the dairy environment. These genes encode technological functions such as bacteriocin production, protein degradation, magnesium and cobalt/nickel transporters, selenium binding, exopolysaccharides (EPS) production, bacteriophage and stress resistance. Beside genes for replication, the small plasmids (pS6, pS7a, pS7a, and pS19) also carry genes important for mobilization and host survival such as type I restriction-modification (R-M) system, metal transporters, enzymes and transcriptional regulators. All plasmids in S50 strain are mobilizable, containing an oriT sequences, while pS127 is self-conjugative and allows for mobilization of the other plasmids. Small plasmids are prone to structural and segregational instability, while pS127 appeared to be segregationally stable thanks to the possession of two partition systems. The main characteristic of plasmid pS74 is EPS production, while plasmid pS127 is characterized by proteinase and multiple bacteriocins, tra locus, phage abortive systems and metal transporters. In addition to LcnA and LcnB, plasmid pS127 encodes several bacteriocin-pheromone molecules and a new bacteriocin named LcnS50, with narrow spectrum of action limited to lactococci, that has been successfully cloned and heterologously expressed., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The paper analyzes the effect of different doses of nitrogen and planting density on grain yield in nine winter wheat varieties and one variety of triticale. All these varieties have been created at the Institute of Field and Vegetable Crops in Novi Sad. It was found that all three individual factors: variety, planting density and the amount of applied nitrogen had a significant impact on yields. Also, the interaction of variety/sowing density had a highly significant effect on yield, while the other interaction effects were not statistically significant. The highest yield was obtained in cultivar NS-40S, and was significantly higher than the of other varieties. On average for all varieties tested, highest yield was obtained when fertilizing with 100 kg ha-1 nitrogen, but was significantly higher only in comparison to the control variant. The highest yield was obtained at densities of 500 germinated seeds per m2, but not statistically significantly different than the yield obtained at 300 and 700 germinated grains/m2. The lowest yield was obtained at the highest planting density of 900 germinated grains/m2.

Wheat cultivars have been studied for the effect of different rates of N fertilizer on their gluten content and its rheological properties, extensibility and adhesiveness. Four cultivars were found to possess HMW-GS 2+12, another four HMW-GS 5+10. It was observed in all cultivars that wet gluten increased in parallel with N rate increase. The cultivars reacted specifically regarding extensibility and adhesiveness. Libellula, a cultivar with poor bread making quality, did not react to the different N rates. Sremica, a cultivar with excellent bread making quality, reduced its gluten quality as the N rate increased. .

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. .

Field experiments with 3 winter wheat (Triticum, aestivum. L); Lasta, Sremica and Pobeda was applied nitrogen (rate N) as follows: 0, 60, 120 and 180 kg Nha-1 from 2000 to 2002. The varieties differed in their biological and production characteristics as well as in technological quality. The analyzed samples belonged to the international ISDV (Internationale Stickstoff Dauer Versuche) stationary field trial established at the Rimski Šančevi Experiment Field of the Institute of Field and Vegetable Crops in Novi Sad. Improvement of end use quality in winter wheat depends on thorough understanding of the influences of environment, variety, and their interaction. Grain protein content (GPC), sedimentation value (SED), energy dough, Hagberg falling number (HFN) and bread crumb quality number were measured. Highly significant differences were detected among the environments (A), rate N (B) and varieties (C) for each of the quality variables. Both variety (V) and environment (E) had a significant effect on quality traits. Significant Vx E interactions indicated that quality trait evaluations must be undertaken for environments. The most influence on protein content and sedimentation value have been climatitic condition. According to lot of environment influence on falling number and dow energy the main part of variance it is genotype and phenotype variability. .

Afield trial was carried out with eight cultivars (Libellula, Drina, Sremica NSR-2, Jugoslavija, Somborka, Lasta and Pobeda) of winter wheat (Trticum aestivum L) representing several different periods in our country's wheat selection and having different potentials for technological grain quality. Six different rates of nitrogen fertilizer were tested: 0, 60, 90, 120, 150 and 180 kgNha-1. Increasing N fertilizer rates resulted in a linear increase of the direct and indirect indicators of quality. The best results were obtained with the cultivar Sremica and the poorest with Lasta, while Jugoslavija and Pobeda were shown to be of approximately the same quality. The contribution of N fertilizer variance to total variance was the largest for protein content (43.7%). N nutrition had a greater influence on protein content in cultivars from the earlier periods of selection. Its effect on sedimentation value, on the other hand, was greater in the recently released cultivars. The contribution of the genetic factor to total variance was the highest for crumb value number (CVN) (58.7%) and bread volume yield (44.2%) and the lowest for protein content (20.8%). The absence of significant differences in the CVN means at any of the N nutrition levels studied resulted from the variability of the indirect indicators closely linked with the direct indicators of baking quality, showing the importance of N nutrition for maintaining the stability of technological quality in winter wheat cultivars.