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This paper presents the results of the cleaning tests of three different natural alfalfa seed lots and three different red clover seed lots performed using seed processing machines. The alfalfa (Medicago sativa L.) and the red clover (Trifolium pratense L.) are two of the most important perennial forage legumes in the Republic of Serbia. Alfalfa and red clover seeds for sowing should be clean, i.e. free from weeds and foreign matter, and of high germination and genetic values. Such requirements can only be achieved by cleaning, i.e. removing all undesirable impurities and poor-quality seeds. The following parameters important for the seed cleaning process and equipment were observed: seed purity, contents of weed and other crop seeds, inert substance content, amounts of processed seeds (kg), seed loss and processing output. The results obtained facilitate (depending on the amount and type of weeds and other impurities found in the alfalfa and red clover seed lots considered) the proper adjustment of the seed processing equipment to obtain the largest possible quantity of quality seeds that are in compliance with the laws and regulations of Serbia.

At present, spreading of mineral fertilizers in Europe is most commonly performed using centrifugal disk spreaders with attached vanes. The motion of an ideal spherical homogeneous fertilizer particle along the straight vane attached to a flat rotating disc was analyzed in this paper. The analysis was performed in the non-inertial reference coordinate system. From the assumptions introduced to enable analytical describing of the real particle motion as well as the general tools of solid mechanics, the ordinary in-homogenous second-order differential equation having constant coefficients arose. Its solution represents an approximation of the real relative motion of the fertilizer particle along the straight radial vane fixed to the flat horizontal disc rotating at a constant angular velocity. However, the solution of this kind can be very useful for the optimization of centrifugal spreader working parameters.

This paper shows the losses created during alfalfa mowing process performed by oscillatory mower with classic cutting apparatus. The losses detected during research process have been divided into two groups: losses caused by increased incision height (over 6 cm), and losses caused by crushing. The total losses made during mowing by the tested mower were calculated by adding the incision height losses and crushing losses. The research results indicate that the minimal losses caused by the incision height are 0.57 % of yields, at the aggregate mowing speed of 3.82 km/h. Aggregate mowing speed increase tend to slightly increase the losses up to maximum values of 1.17 % at the mowing speed of 8.17 km/h. The crunching losses ranged from minimal 0.31 % at the minimal aggregate mowing speed. The average total losses were 1.18 % of yields at the average aggregate mowing speed of 5.76 km/h.

Intensive crop production is based on the use of various means of mechanization. Significant place in applied mechanization take sowing aggregates. Emphasizing the importance of applied sowing aggregates and their technological characteristics and quality of work (appropriate and optimal deployment of seed depth, length and width of the sowing layer) is understandable, especially if one takes into account the fact that an omission made in the technological process of sowing later practically almost can't be removed. The aim of our study was based on field-laboratory and terrain to test the mechanical seeders 634.23 IMT in sowing rye, determination quality and reliability of drill work. Based on these results it was concluded that in terms of proper adjustment of drill and well-executed presowing preparation, planter IMT 634.23 can achieve a good distribution of seeds of rye on the surface, with a spacing of 40-60 mm over 60% of seeds. Transverse distribution of seed rye was satisfactory, given that the highest content of rye seeds were grouped at a distance of 120-140 mm and amounted to over 65%. No marked significant differences in seeding depth intervals in the group which have been investigated. IMT 634.23 seeder can be used successfully for sowing rye and it belongs to a group of reliable seeder with good productivity and reliability that has been shown during operation.

The study presents the effect of cutting height (10, 15 and 30 cm) on yield, nutritional value and chemical composition of silage corn. The experiment was carried out under dryland conditions and the silage corn was harvested with three types of self-propelled silage harvesters. Cutting height increased linearly with increasing operating speed of silage harvesters. For all types of silage harvesters, the cutting height of 30 cm had a statistically significant (p=0.05) effect on losses of yields. The numerical value of the R2 factor (from R2 = 0.8978 to 0.9896) shows a strong dependence in all harvesters for all three cutting heights. The regression coefficients (b) show a significant deviation from the theoretical cutting height at 10 and 15 cm (b = 0.6676 and b = 0.6715), and very significant (b = 2.0249) at the theoretical cutting height of 30 cm. With an increase in cutting height, the nutritional value of silage increased. At a cutting height of 30 cm, during the test period in all types of harvesters, the crude protein (CP) content was significantly (p=0.05) higher than at a cutting height of 10 cm (harvester C = 6.94% at 10 cm, harvester B = 8.15% at 30 cm). The cutting height of 30 cm influenced a significantly (p=0.05) lower crude fiber (CF) content of harvester Claas Jaguar 850 (21.19%), compared to John Deere 6810 (24.33%) at a height of 10 cm. The crude ash content (CAsh) did not vary significantly under the influence of cutting height. Starch content was statistically higher (p=0.05) in all types of silage harvesters during the test at a cutting height of 30 cm (28.2% harvester New Holland FX 28, 33.8% harvester Claas Jaguar 850). The content of calcium (Ca) was significantly higher at a height of 30 cm for harvesters John Deere 6810 and Claas Jaguar 850 in the third year, while no significant difference was found for harvester New Holland FX 28. For phosphorus (P), there was no significant difference depending on the cutting height, but it did exist depending on the year. [ABSTRACT FROM AUTHOR]

The paper presents the results of three - year tests (I, II, III) of finishing alfalfa seed of three different purities. Natural alfalfa seeds were classified into three groups: 1) without the presence of quarantine weeds; 2) with the presence of quarantine weeds of Cuscuta spp. and Rumex spp., but in smaller quantities; 3) in which there were also quarantine weeds in larger quantities. The alfalfa seeds were cleaned on a selector with sieves and on a magnetic separator manufactured by Emceka-Gompper. Depending on the purity of natural alfalfa seed, the finishing process had to take place in one to three passes through a system of machines, which caused different finishing output and losses of finishing processed alfalfa seed (9.2 to 38.0%). After finishing, the highest quality of processed seeds was from the group with the highest quarantine weeds (group 3), which was reflected in the lowest percentage of hard seeds (16%) and the highest percentage of germination (83%) in all years. This is also shown by a highly significant negative correlation between germination and hard seed (r=-430) after three years of seed processing. [ABSTRACT FROM AUTHOR]

Observed through agronomic and economic significance, cereals represent the most important group of field plants, and the protein content in grain is the most important chemical parameter of complex grain quality. The research was conducted in order to determine the influence of the variety and different doses of nitrogen on the grain yield and protein content in triticale grain. The experiment, set up according to a random block system in four replications on eutric cambisol soil in the north of Montenegro, included five varieties of winter triticale (Odyssey, Kg-20, Triumph, Rtanj and Tango). In addition to the control (variant without fertilization), four more fertilization variants were applied. The results of the research showed that the application of fertilizers has a significant influence on the values of the observed traits on the one hand, but also that the grain yield and protein content in the grain is largely conditioned by the genotype. In this regard, the highest average protein content in the grain had the variety Triumph in both tested years. The protein content of all tested varieties was significantly lower in the control variant compared to the fertilized variants. The highest grain yield in the first year had the variety Tango while the highest yielding variety in the second year was variety Rtanj. [ABSTRACT FROM AUTHOR]

The quality of combine harvester work in the rye harvest is reflected in terms of the amount of realized losses and quality of harvested grain weight. The quality of combine harvester work depends on several factors: the condition of the crop, defining the relevant parameters for combines, technical correctness and staff skills. Quality of work is significantly decrease when key parameters are not well coordinated, resulting in increased losses of rye grain and a high proportion of impurities in harvested mass in the harvester bunker. The aim was to determine the effects of combines ZMAJ 135B and ZMAJ 143 in the rye harvest in the observed area. Work method determines the loss on the header and harvesting device depending on the changes: peripheral winches speed; combine speed, underdrum-drum distance at the entrance and evaluating the quality of harvested weight (content of whole, broken, poorly grains and other particles). Header losses were determined using a wire frame of 1m², located after the passage of the side behind the combine header and harvesting device by setting the appropriate container, during harvester motion, between front and rear wheels at an angle of 10- 20° in regard to the movement direction. The quality of harvested mass was determined by taking samples from the harvester bunker and the determination of the percentage content of healthy (whole), broken grains and impurities was performed later in the laboratory. The applied methodology is standard for this issue and is related to field-testing laboratory and exploitation wheat combine in the single-phase rye grain harvesting. The obtained results allow to point out the advantages and disadvantages of the applied concepts of different wheat combine. Header largest losses were registered in the device combines ZMAJ 143 and were 25.77 kg ha-1 (1.18%) and lowest in combine ZMAJ 135B, amounting to 14.76 kg ha (0.65%-1). The highest content of whole rye grain was in combine ZMAJ 135B and amounted to 97.34 in 1500, and the lowest in combine ZMAJ 132 94.59%. Based on these results it was concluded that the ZMAJ 135B harvester worked better than the harvester ZMAJ 143, with lower losses of rye grain on the harvester unit header, and higher content of whole grain with a significantly lower share of impurities in relation to other investigated harvester. The general conclusion of our research is that harvester ZMAJ 135B can be successfully used in rye harvest in a given area and with proper optimization of labor exploitation and operator training can gain full expression. [ABSTRACT FROM AUTHOR]