Search

Intensive agricultural practices affect soil compaction, and their indirect and direct effects on crop growth and development are an increasingly important focus of scientific research. The objective of this study was to determine the influence of different tillage systems on soil compaction and to observe the influence of tractor tire pressure on penetrometer resistance during sowing. The three-year study was conducted on the heavy pseudogley soil of Brod-Posavina County in the Republic of Croatia. During the research, crops were observed in the following cropping sequence: soybean (Glycine max L.) in the first year, maize (Zea mays L.) in the second year and winter wheat (Triticum aestivum L.) in the third year. The tillage systems as the main study factor were conventional tillage (CT) plowing to a depth of 35 cm, disc tillage (DH) to a depth of 15 cm, loosening (CH) to a depth of 30 cm, and undermining (SS) to a depth of 50 cm. The following pressures were used as a subfactor of this study, namely the pressure of the front and rear tires of the tractor during sowing: p1 (front 1.0 bar/rear 0.8 bar), p2 (front 2.0 bar/rear 1.6 bar), and p3 (front 3.0 bar/rear 2.4 bar). The tillage systems applied resulted in different soil compaction, thus the deepest tillage SS had the lowest resistance and the DH tillage had the highest resistance in all three experimental years. Penetrometer measurements showed the influence of tire pressure p1 on reducing compaction as early as the first year in 2017, while in the last year of research in 2019, tractor tire pressure p3 during sowing contributed to a significant increase in soil compaction.

Effects of soil tillage (CT-conventional, SS-subsoiling, CH-chiselling, DH-disk-harrowing and NT-no-till) and nitrogen rate (reduced N1, optimal N2 and luxury N3) on yield and yield components of maize and winter wheat in two different agricultural subregions of Croatia (Magadenovac and Cacinci site), have been studied in years 2013–2014 as a part of long-term experiment. Maize yield and yield components were influenced by site properties, tillage and nitrogen treatments. The highest yields and yield components were recorded at site Magadenovac on N2 and N3. The lowest values of the yield and yield components of maize were recorded on NT and were significantly lower than CT, SS, CH and DH, among which no significant differences were recorded. Winter wheat yield and yield components were affected by site properties and nitrogen rates while soil tillage treatments had influence only on grain and straw yield and plant height. Winter wheat achieved maximum yield and yield components on a N3 and N2 and at Magadenovac site. Winter wheat grain yield was decreasing in following order: SS &gt, DH &gt, CH &gt, NT &gt, CT. The obtained results indicate the importance of optimal nitrogen fertilization and the possibility of implementation of conservation tillage for maize and winter wheat production in different agroecological conditions.

Enormous fossil fuel consumption and rising of CO2 exhaust gasses emission has serious influence on greenhouse effect and global climate warming. Nowadays rising fossil fuel prices are leading to an increasing of agricultural products value and awareness of energy efficiency importance. Soil tillage is the largest fuel energy consumer, so there is a need to conduct studies to innovate techniques which can lower fuel consumption. This study evaluates the effects of four different tillage treatments (CT - conventional, DH - disc harrowing, CH - chiselling, SS - subsoiling) on fuel consumption and wheel slippage. For this research a four-wheel drive tractor was aggregated with reversible plough, discs harrow and with subsoiler as tillage implements. The results indicated that fuel consumption was highest on CT and the lowest on DH treatment. CH treatment had the lowest wheel slippage percentage and average fuel consumption 19, 7% higher than DH treatment in all three years of the study. Mean wheel slippage at CT, DH, CH, SS treatments was as follows: 17, 54% ; 21, 47% ; 8, 64% ; 23, 56% respectfully. Wheel slippage at CT, CH and SS treatments was related to fuel consumption (as follows: 30, 84 lha‒1, 12, 92 lha‒1, 23, 1 lha‒1) and all systems were affected by tillage depth.

One necessary precondition for achieving stable and high grain and oil yields of sunflower for a certain agroecological area is the right choice of hybrids, but also the determination of the optimal plant density (number of plants per unit area) for these hybrids. Therefore, in order to determine the influence of plant density and hybrid on grain yield, oil content and oil yield of sunflower, an experiment was conducted with three plant densities (57000, 65000 and 75000 plants ha-1) and 24 sunflower hybrids at the Osijek locality. The hybrid had the largest influence on the phenotypic expression of the mentioned traits, while the plant density and the plant density x hybrid interaction had a much smaller influence. On average, the highest grain yield, oil content and oil yield were achieved in the highest plant density. Hybrid H-16 had the highest grain yield (6.712 t ha-1), hybrid H-11 had the highest oil content (54.89%), and hybrid H-13 had the highest oil yield (3.144 t ha-1). High grain yield, oil content and oil yield of experimental sunflower hybrids indicate improvement in the breeding process at the Agricultural Institute Osijek. These hybrids can be considered as promising material in further research for the purpose of applying for recognition and commercial production.

The effect of different conservation soil tillage (CST) treatments and different level of nitrogen fertilization on Fusarium wheat grain infection on two locations are presented in this paper. The research was conducted on winter wheat with different soil tillage treatments: conventional tillage to 30 cm depth, subsoiling to 35-40 cm depth, chiselling up to 25 cm, disk-harrowing to 10-15 cm and no-tillage, without any tillage treatments and three different nitrogen rates (N1 - amount reduced by 30% of recommended; N2 - according to standard recommendation and N3 - amount increased by 30% of recommended). The occurrence of Fusarium species was determined in all the tested variants of tillage and fertilization treatments. The effect of reduced fertilization (N1) on Fusarium sp. grain infection in all tillage treatments was statistically lower in comparison with other (N2 and N3) nitrogen treatments. The lowest percentage of wheat grains infected with Fusarium sp. was recorded in conventional tillage on location Magadenovac and no tillage treatments on location Cacinci.

The almost closed structure of the Pannonian Basin makes it an exceptional natural laboratory for the study of the water and energy cycles, focusing on the physical processes of relevance. The Pannonian Basin Experiment, under the umbrella of the Global Energy and Water Exchanges project of the World Climate Research Programme, aims to achieve a better understanding of the Earth System components and their interactions in the Pannonian Basin. The scientific basis of the PannEx supports research that can better translate and deliver relevant climate data, information and knowledge for societal decision making through the national hydro-meteorological and climate services, research institutes and universities. We outline the framework for the development of the PannEx in the light of international efforts to provide scientific support and involve international research community in integrated approach towards identifying and increasing adaptation capacity in the face of climate change in the Pannonian Basin. As such, PannEx dedicated observational and modeling efforts also strive to reach results with the global impact. Keywords: Pannonian Basin, Pannonian Basin Experiment (PannEx), Earth System, Integrated modeling, GEWEX, Adaptation, Mitigation

The hypothesis that the optimal nitrogen rate for crop yield and nitrogen use efficiency (NUE) are affected by tillage treatment, crop type and soil properties (type) was evaluated by an experiment which include five different tillage treatments (CT-conventional, SS- subsoiling, CH-chiselling, DH-disk-harrowing and NT-no-till), three levels of nitrogen rates (N1-reduced, N2-optimal and N3-luxury), on two different soil types (Stagnosol and Gleysol) and with two different crops (maize and winter wheat). Soil and plant samples were taken from the first and second year in the second four- year crop rotation cycle. The highest value of soil compaction (ρb-bulk density and PD-packing density) as well as the lowest soil total porosity (P) was found, on average for all tillage treatments, on Gleysol in both experimental year in the root zone (20–40 cm). At all depths the highest values of ρb and PD were recorded for DH treatment on Gleysol and for soil porosity for NT treatment on Stagnosol. Grain yields, biomass, and harvest index of maize and winter wheat on both soil type respond positively to conservation tillage treatment, but with different significations. Soil cover crop residues were significantly affected by soil treatment and nitrogen fertilization (P < 0.01), and decreasing in the following order: NT > CH > SS > DH > CT on both soil types. The average NUE in general decreased successively under N1, N2 and N3 with respective NUEs on Stagnosol 58.5, 49.5 and 36.0 kg kg−1 for maize and 59.9, 45.3 and 35.9 kg kg−1 for winter wheat. Corresponding values on Gleysol were 78.5, 69.4, 52.0 kg kg−1 and 46.3, 51.3, 44.0 kg kg−1. The grain and biomass of winter wheat increased from N1 to N2, whereas from N2 to N3 they decreased, increased or remained almost the same depending on the tillage system and soil type. The effect of all the investigated tillage treatments on NUE and crop yield was variable depending on particular tillage system, crop type and soil type. The results indicate that, from the NUE and crop yield viewpoints, the N2 and N3 nitrogen rates are respectively most and least suitable on both soil types, depending on soil treatment. Irrespective of the nitrogen application rate and tillage treatments, the NUEs were the most comparable treatments higher in the more productive Gleysol (32.7–92.5 kg kg−1) than in Stagnosol (26.4-76.7 kg kg−1).

Cover cropping in fallow period brings many benefits in organic farming and weed suppression is one of the possible effect. The main aim of this two year research (2008/09-2010) was to determine the influence of winter cover crops incorporation on weediness in organic popcorn (Zea mays everta Sturt) production. The field trial was set up at the lessive soil of the Eastern Croatia (45°38' 46, 52'' N / 18°23' 32, 73'' E) as complete randomized block design in four repetitions. The five cover crops treatments were used: Wr – winter rye, Ww – winter wheat and V - hairy vetch, as single crops, and cover crops mixtures WrV and WwV. Fallow area was used as a control: Z (zero). Sampling to quantify the dry matter and incorporation of cover crops were performed just before full flowering period of cover crops and the popcorn maize was sown right after. Dominant weed species determined in this trial were Ambrosia artemisiifolia L., Amaranthus retroflexus L., Echinochloa crus – galli (L.) PB. and Setaria glauca (L.) PB. Treatments with the highest shoot production were Wr and WrV. The weediness in popcorn maize was higher at winter cover crops treatments compared to control. Looking at winter cover crops treatments only, the least weeded was WwV mixture regarding total weed number, and V and Wr treatment showed the lowest weed height, whereas height of the popcorn maize was the lowest at Wr treatment. The highest weed aboveground biomass was recorded on WrV treatment. Results of this experiment indicate the increasing of weed infestation caused by winter cover crops incorporation.

Eight different soil tillage systems (TS) for winter wheat after soybean crop production were compared at the chernozem soil type in Croatian Baranya region in a 4-year period (2001/2002, 2002/2003, 2003/2004, 2004/2005). Tillage systems were: CT) conventional tillage, based on autumn mouldboard ploughing; DH) autumn disc harrowing; CH) autumn disc harrowing + chiselling; NT) No-tillage; CSDW) DH for winter wheat, alternated with CT for previous crop soybean; CWDS) CT for wheat, DH for soybean; CsNw) NT for wheat, CT for soybean; and CwNs) CT for wheat, NT for soybean. The dry conditions experienced in 2002/2003 decreased at half winter wheat grain yield at treatments NT and CwNs. The most stable grain yields were obtained by CT, CH, and CSDW in the third of 4 experimental years. CsNw, DH and CWDS did not result in significant crop yield reduction when compared to CT. There was no striking regularity regarding applied TS at the grain yield components. The strongest effects on yield and yield components for winter wheat were due to the climate conditions. TS had a significant effect on the grain yield and crop population in the earing stage in all 4 experimental years. The biggest difference in stem height was determined between CWDS and CsNw. Mass of plant, number of grains per spike, and hectolitre mass were greater under CT than under other TS. Coefficient of tillering and mass of 1000 grains had approximate values for all applied TS. In conclusion, CH, CSDW, and CsNw produced similar or slightly better quality properties than CT and these systems could be presented as an even-handed replacement for soil tillage.

Post-harvest cropping is one of the solutions to the growing demands both in food and bio- energy. The sudan grass (Sorghum bicolor subsp. drummondii), trials were set up at three sites in northeastern Croatia during the summers of 2009 and 2010. After the harvests of main crops (winter barley, winter wheat or oilseed rape), three soil tillage treatments were applied: CT) mouldboard ploughing (25-30 cm deep), followed by disk harrowing and seedbed preparation ; HDH) two passes by disk harrow (15-20 cm deep), followed by seedbed preparation, and ; LDH) single pass of disk harrow only. Beside the no- side-dressing control (NO), four sidedressing were applied twice: KAN) 100 kg ha-1 KAN (27 % N) in granular form ; UF) 60 kg ha-1 urea (46 % N), applied as 5 % foliar fertilizer ; PM1) 8 l ha-1 of foliar fertilizer "Profert Mara", which contains macro and micro nutrients, and PM2) double rate of PM1. Significant differences among soil tillage treatments were present. In both years, all side-dressing treatments had higher yield than control. Treatments KAN, UF and PM1 were not different among themselves, whereas PM2 had higher dry matter yield. Results are suggesting better effects of foliar than granular fertilizers for post-harvest sown sudan grass, either in drought (year 2009) or over wet (year 2010) conditions.

Winter wheat and soybean were grown under field conditions on chernozem soil of Knezevo, Croatia, for four years (from 2002 to 2005) in three applied soil tillage treatments: a) CT – conventional soil tillage, based on mouldboard ploughing, b) DH – soil tillage based on diskharrowing instead of ploughing ; and c) NT – no-tillage. Both crops in showed decreasing concentration of Zn within the plant tissue as a result of the soil tillage reduction in the order CT>DH>NT, presumably due to the limited roots growth in lesser disturbed soil at DHand NT treatments. Winter wheat recorded generally lower than optimal Zn concentrations and higher P:Zn ratios at reduced soil tillage treatments, as a result of lower Zn uptake. The recommendation for the winter wheat production by reduced soil tillage is additional Zn fertilization, whose exact amounts and way of application shall follow further research.

The use of cover crops is a recognized and well known method for soil tilth, soil nutrients conservation and weed suppression, whereas the utilization of winter cover crops for early spring fodder is not sufficiently investigated, especially in organic agriculture, where special rules have been applied. The experimental set up near Valpovo, Croatia, at the eutric brown cambisol soil type, during the years of 2007 and 2008, aimed toward effects of different cover crops and their mixtures on the biomass production and cover crops potential for early spring fodder. The experimental set- up was CRBD in four repetitions, with eight cover crop treatments after soybean (Glycine max L.) and pop-corn maize (Zea mays L. var. everta): WW – winter wheat (Triticum aestivum L.), RY – winter rye (Secale cereale L.) FP – field pea (Pisum arvense L.) ; HV – hairy vetch (Vicia vilosa L.) ; WF – mixture of WW and FP ; WH – mixture of WW and HV ; RF – mixture of RY and FP ; and RH – mixture of RY and HV. The highest dry biomass production treatments were WW and RY after soybean with 3123 and 2987 kg of dry matter per ha, and RY and WW after maize, with 1656 and 1399 kg of dry matter ha– 1, respectively. Regarding protein production potential, WW and RY treatments after soybean yielded 226 and 183 kg of proteins, whereas HV and WH treatments after maize produced 155 and 143 kg of proteins, respectively.

The winter barley crop growing has not been adequately researched regarding soil tillage systems, especially in crop rotation with the soybean, both crops gaining importance as food or fodder. Also, productivity of such crop rotation in low nitrogen environment is especially interesting for organic crop growing, where mineral nitrogen fertilization is not allowed. The research on two soil tillage systems, the conventional one, based on mouldboard ploughing (PLOW) and reduced soil tillage, based on discharrowing (DISC), with no other nitrogen source except symbiotic soybean bacterial fixation, was conducted at the experimental site Bokšić (Croatia), during the seasons 2004/05 and 2005/06. Results showed low but stable yields of winter barley, between 2.1 and 2.6 t ha-1, where PLOW treatment recorded lower yield than DISC in 2005, and usual soybean yields (between 2.8 and 3.4 t ha-1), with higher soybean grain yields for PLOW only in 2006. The absolute mass and hectolitre mass did not show any statistical differences among treatments either., Uzgoj ozimog ječma nije adekvatno istražen glede sustava obrade tla, posebice u plodoredu sa sojom, a oba usjeva dobivaju na važnosti kao hrana za ljude ili krma za životinje. Isto tako, produktivnost ovakvog plodoreda u uvjetima niske gnojidbe dušikom je osobito zanimljiva za ekološku poljoprivredu, gdje korištenje mineralnih dušičnih gnojiva nije dopušteno. Istraživanje dvaju sustava obrade tla, konvencionalnog, baziranog na oranju lemešnim plugom (PLOW), te reduciranog, baziranog na tanjuranju (DISC), bez ikakvog izvora dušika osim dušika simbiotski vezanog kvržičnim bakterijama na soji, provedeno je na pokušalištu Bokšić (Hrvatska), tijekom sezona 2004/05-2005/06. Rezultati su pokazali niske ali stabilne urode ozimog ječma, između 2.1 i 2.6 t ha-1, gdje je na PLOW tretmanu zabilježen niži prinos nego na DISC tretmanu u 2005. godini, te uobičajene urode soje (između 2.8 i 3.4 t ha-1), s višim urodima zrna soje na PLOW tretmanu samo u 2006. godini. Razlike apsolutne i hektolitarske mase među tretmanima nisu bile statistički opravdane.

Although organic crop production has numerous advantages, concerns about economic sustainability, both environmental and financial, make farmers reluctant to convert their conventional production into the organic production. Certain agricultural methods, such as second crop use, can alleviate some problems regarding soil tilth, erosion prevention, nutrients availability and weed control, thus contributing toward more sustainable crop production. Also, the added value crop growth, such as maize (Zea mais L.) hybrid's parental line production, with lower yields but higher prices, can contribute to sustainability of organic production. In order to test the hypothesis that the use of second crops can contribute toward the sustainability of organically grown maize after soybean (Glycine max L.) as a previous crop in the crop rotation, the experimental site was established in Valpovo, Croatia, in the eutric brown soil type, during the years 2005 and 2006. The experimental design was set up as a CRBD in four repetitions, with six second crop treatments: CT – Control, without second crop; WW – winter wheat (Triticum aestivum L.) second crop; RY – rye (Secale cereale L.) second crop; FP – fodder pea (Pisum arvense L.) second crop; WP – mixture of WW and FP; and RP – mixture of RY and FP. In order to assess the soil surface protection and evaluate the weed suppression, the second crop coverage had been recorded. Regarding the economic sustainability, the second crop use depending costs were analysed in relation to the extra produced maize yield. The RY treatment had the highest profitability, followed by WW, RP and O. The WP and FP revealed lower relative profitability than O, thus presenting the evidence of sustainability risk of these treatments., Premda ekološka poljoprivreda ima brojnih prednosti, zabrinutost zbog održivosti, i ekološke i ekonomske, farmere često odvraća od prijelaza s konvencionalne proizvodnje na ekološku. Intenzifikacijom plodoreda uporabom postrnih usjeva, mogu ukloniti neke probleme vezane za ugorenost tla, prevenciju erozije, dostupnost hraniva i suzbijanje korova, doprinoseći na taj način održivosti proizvodnje usjeva. Također, uzgoj usjeva s dodatnom vrijednošću, kao što su roditeljske linije za proizvodnju hibrida kukuruza (Zea mais L.), s nižim prinosima ali višom cijenom, može pridonijeti održivosti (profitabilnosti) ekološke proizvodnje. U namjeri da se potvrdi hipoteza da postrni usjevi mogu doprinijeti održivosti ekološkog uzgoja kukuruza u dvopoljnom plodoredu sa sojom (Glycine max L.) kao prethodnim usjevom, postavljeno je pokušalište u Valpovu, Hrvatska, na eutričnom smeđem tlu, tijekom 2005. i 2006. godine. Pokus je postavljen kao potpuno slučajan blok raspored u četiri ponavljanja, sa šest tretmana postrnih usjeva: CT – kontrola, bez postrnih usjeva; WW – ozima pšenica (Triticum aestivum L.); RY – ozima raž (Secale cereale L.); FP – stočni grašak (Pisum arvense L.); WP – smjesa WW i FP; te RP – smjesa RY i FP. U cilju određivanja zaštite površine tla i evaluacije suzbijanja korova, zabilježena je pokrivenost postrnim usjevima. Glede isplativosti, analizirani su relativni troškovi upotrebe postrnih usjeva u odnosu na dodatno proizvedeni urod kukuruza. RY tretman je zabilježio najvišu profitabilnost, a pratili su ga tretmani WW, RP i O. Tretmani WP i FP pokazali su se manje profitabilni od O, time pružajući dokaze o rizičnoj održivosti ovih tretmana.

Maize is one of the most important crops in Croatia, especially for the Panonian part - Slavonia and Baranja region, which is producing, in average, 30% of total maize production in the country (Kovacevic and Josipovic, 1998). The practice is mainly conventional, based on standard soil tillage including ploughing as primary tillage operation, which is the most expensive, slow, with high demands for fuel and labour. Also, it can be ecologically unfavourable and non- sustainable. Meanwhile, in the latest twenty years the knowledge about soil tillage in Croatia and its vicinity (Birkas and Gyuricza, 2000) has been changed, as in many countries in the world, toward simplification, reduced, rational tillage, which was the subject of research by Croatian authors, for instance Zugec (1984), Culjat and Tabakovic (1991) and Jug et al. (2006). Diskharrowing or chiselling, as a primary tillage operation, was not researched thoroughly enough, especially in the light of other reduced tillage systems, such as no-till, where equipment price of special no- till planters and heavier tractors can be limit for average farmers, especially in the changing climate conditions, as emphasised by Dobo et al. (2006). The scope of this paper was to optimise soil tillage for maize in longer period of time.

Four different tillage systems were compared in soybean [ Glycine max (L.) Merr.] production on one experimental field (chernozem) located in the Baranya region of northeastern Croatia in 2002 and 2003. The dry conditions experienced in 2003 exacerbated the negative effects of no-tillage on soybean yield. The 2-year average yield of soybean was significantly lower under no-tillage (NT) than in the conventional tillage (CT), soil loosening (SL) and disc harrowing (DH) treatments. The soybean oil and protein contents were very similar in all the tillage systems over the 2-year average. Soybean crude fibre (%) was affected by the main effect of tillage. Averaged over 2 years the crude fibre (%) of soybean grain was greater under NT than in the CT, DH and SL treatments. The ash (%) generally increased as tillage declined.

The trial for winter wheat (Tritictum aestivum L.) or spring barley (Hordeum vulgaris L.) in rotation with maize (Zea mais L.) on lessive- pseudogley in semiarid to semihumid climate of Eastern Croatia was set up during years 1996- 1999 with five soil tillage systems: PL) Conventional tillage based on ploughing ; PD) Conventional tillage after diskharrowing for previous crop in preceding season ; DP) Diskharrowing after conventional tillage for previous crop in preceding season ; DD) Continuous diskharrowing, and CD) Chiselling and diskharrowing. During first and second season (1996/97 and 1997/98), recorded winter wheat grain yields were not different, with PL having the highest and DD the lowest yield. Maize showed next differences in first season: PL=PD > CH=DD=DP, and in second season PD=PL=DP=CH > DD. In 1999, spring barley replaced winter wheat, and yields were: PL > DP > PD > CD > DD. Maize yields recorded were: PL > PD > DP > CH > DD. The grain yield results, together with hectoliter mass and mass of 1000 grains, supported that PL can be replaced with other tillage systems for winter wheat and spring barley, whereas continuous diskharrowing may have substantially lower yields for maize during unfavourable years.

Croatian Baranja region contains soils with highly quality crop production properties, but the knowledge of the effects of reduced tillage systems is lacking. Our investigations were conducted under field conditions at Knezevo site chernozem in four replications. They included four soil tillage systems (CT: conventional tillage, with ploughing up to the 30 cm as a primary tillage ; DS: diskharrowing up to the 15 cm ; CH: chiselling up to the 30 cm + diskharrowing ; NT: no-till seed drilling), both for winter wheat (Triticum aestivum L.) - soybean (Glycine max L.) in crop rotation during three growing seasons (2002- 2004). All measured crop properties were strongly affected by different seasons, especially with the season of 2003 with extreme drought. Crop biomass in five growth stages for winter wheat showed that at the beginning DS and CH had stronger growth than CT and NT, but differences vanished toward final stages. Winter wheat grain yield achieved by reduced tillage systems was in average either higher (CH=5.59 t ha-1) or not different (5.38 and 5.23 t ha-1 for DS and NT, respectively) than CT (5.28 t ha-1). Soybean growth was consistently the most impaired at NT system, especially at the full maturity stage, where also DS and CH had lower biomass than CT. Soybean grain yield confirmed biomass results, since NT (2.11 t ha-1) had always the lowest yield, when compared with other tillage systems (CT=2.88, CH=2.77 and DS=2.72 t ha-1). Our conclusion is that within the Croatian Baranja environmental conditions is possible to replace soil tillage based on the ploughing for winter wheat and soybean with reduced soil tillage systems based on disking and chiselling, whereas no-till system still needs solution which will address drought-related problems.

Soybean were grown under field conditions on chernozem soil for four growing seasons (from 2002 to 2005). Three treatment of soil tillage were applied as follows: a) conventional tillage, b) reduced tillage (diskharrowing instead of ploughing) and c) no-till (zero-tillage). In general, the characteristics of growing season (the factor „ year“ ) were more influncing factor of soybean nutritional status (aerial part in stage of full-developed pods) in comparison with the soil tillage. In our study, low influences of applied soil tillage treatments on nutritional status of soybean were found because significant differences on soybean composition were found only for four (Cu, Cr, Sr and Ba) from total 20 analysed elements. For example, conventional tillage resulted by the higher plant Cu (by 15% and 18% in comparison with DH and NT, respectively), and the lower plant Sr (by 12% and 16%, respectively) and Ba (by 26% and 23%, respectively), while under DH conditions by 22% lower plant Cr was found. Main nutrient status (P. K, Ca, Mg, S....) were independent on soil tillage. For this reason, usual fertilization practice is recommended for possible application of soil tillage reduction under conditions of calcareous chernozem.

Soil degradation refers to processes that lead to a decrease in its fertility or production capacity and other useful roles that the soil plays in the ecosystem due to human activity or natural conditions. The soil is exposed to the processes of physical, chemical and biological degradation. From the physical processes of degradation, the following can be distinguished: loss of fertile soil due to erosion by water and wind, deterioration of the structure and soil compaction, and desertification. Chemical processes of soil degradation refer to: leaching of nutrients and toxicity due to acidic or basic soil reaction (salinization or alkalization) and harmful substances in the soil. The decrease in the content of organic matter and biological diversity of the soil belongs to the biological processes of degradation. All these processes, which are primarily human-caused and less the result of natural conditions, adversely affect the fertility, productivity, quality and health of the soil. Milder forms of soil erosion by water in Croatia are possible on 27.2%, and stronger forms on 48.3% of the surface. On steep cliffs, soil collapse is also possible. Along with soil erosion, a big problem in the world and in our country is anthropogenic soil compaction. About 4% of the total area of degraded soils in the world belongs to compacted soils. One of the key problems is soil desertification, and about 30% of arable land in the world is exposed to this process. Eastern Slavonia, with its arid climatic conditions, is the most exposed to desertification in our country. Acidification, salinization and alkalization should definitely be distinguished from the chemical processes of degradation. About 14% of the world's total soil fund belongs to acidic soils, and 2.4% to saline and alkaline soils. Around 28% of acid soils and less than 0.01% of saline and alkaline soils can be distinguished here. Many authors point out that the degradation of the biological characteristics of the soil is a big problem in the world and in our country. In our soils, which are in intensive agricultural production, humus is often less than 2%, and this is of course reflected in the decline in soil biodiversity. In the paper, the causes and consequences of these degradation processes are detected and appropriate guidelines are given for better soil management and measures for its remediation are recommended.

Soil erosion by water is a pervasive and a significant environmental problem affecting all sloping terrains, causing soil physio-chemical changes and soil displacement. Considerable modification of the soil chemistry leads to decrease in soil fertility and in a disrupted nutrient balance. In this context, soil pH and organic matter content are of great importance as fundamental factors of soil fertility. Therefore, the basic objective of this work is to determine the influence of inter-row use on the soil quality affected by water erosion in the vineyards. The research included different treatments in two vineyards ; grassed inter-rows and bare inter-rows. The vineyards are located in the same position, slope and soil type. Grassed inter-rows in the vineyard belongs to the family farm Mladen Papak, while the treated bare soil in the rows belongs to the vineyard of the family farm Drago Papak. The results of laboratory analysis show the influence of different soil use in vineyards on the changes of soil pH and soil organic matter content. Based on them, it is recommended to grass the inter-row space due to reduced soil erosion by water, retention of plant mass and organic matter, non-compaction of the inter-row space and easier passage of machinery through the rows. Also, it is important to emphasize and determine the direction of planting rows in vineyards because the direction of the row itself negatively can affect the increase of soil erosion by water. The results of this research indicate the importance of applying all preventive measures in reducing soil erosion by water on sloping terrains.

Buckwheat and soybean are regarded as important crops in organic production and their pro- duction could contribute to achieving farm sustainability. However, this significance derives from a preceding effect, but less research is done on these crops as major crops. The aim of this study is to examine soil properties under different mulches and bio-fertilizers in soybean NS Kaca and buckwheat Novosadska. The experiment was set up in semiarid conditions in the Center for organic production in Selenca with 3 types of mulches: wood chips, straw, living mulch as well as commercial fertilizers and soil enhancers: organic NPK fertilizer, Ascophyl- lum nodosum extract and microbiological stimulator. Mulches were helpful in maintaining the physical properties of soil, but they could not preserve the chemical properties of soil. Buckwheat manifested better chemical and physical soil properties compared to soybean. Our results showed differences regarding mulch application in terms of impact on soil, which could serve as a basis for improving the management of buckwheat and soybean under organic pro- duction systems in semiarid conditions.

Microbiological liquid inoculants are becoming increasingly popular among agricultural producers because of easier and faster application. Production costs of liquid inoculants are lower in comparison to rigid, most often peaty, which for a long time occupy the first place in the production of soybean inoculants. The composition of liquid media that supports the growth of bacterial cells during the shelf life of the inoculants is crucial, and for maintaining a high number of cells, it is recommended to add suitable additives that improve the survival of cells in liquid medium. In order to determine the optimal composition of the nutrient medium, a study was conducted to determine the Bradyrhizobium japonicum strain viability on yeast-mannitol medium, modified yeast-mannitol medium and glycerol medium, two temperatures (4 and 25 °C) over a period of 6 months. The highest number of rhizobial populations was determined and ranged from average 5x108 to 4x109 cfu ml-1 depending on the type of nutrient medium at 4 °C. In further research, additional improvement of the liquid nutrient medium is required to maintain a high number of viable rizobial cells for a longer period of time.

The research was conducted on stagnic luvisol of loamy texture (N: 460 01´ 12ʺ ; E: 160 34´ 28˜) on testing ground of Križevci College of Agriculture. Research objectives were related to determining the influence of different tillage methods on the height of maize and soybean plants, number of soybean pods, average number of seeds in the pod, ear yield and maize grain yield. More intensive tillage varijants hade a more favourable influence on the height of maize plants, ear yield and grain yield, i. e. the application of autumn basic soil tillage achieved better results for almost all researched agricultural properties. In the process of soybean cultivation, the most intesive tillage method indicated the biggest plant height and the biggest number of pods per plant, as well as the highest number of seeds within a pod (variant E). It was established that more intensive tillage had more favourable influence on the researched agricultural properties of maize and soybean in comparison to reduced tillage methods.

The scope of this research was to determine concentration of chloroplast pigments in the winter wheat leaves influenced nitrogen fertilization under reduced soil tillage. The research for winter-wheat has been conducted at the Virovitica-Podravina County in 2008/2009 , with six different nitrogen rate (controla-0 kg N ha-1, 30 kg N ha-1, 60 kg N ha-1, 90 kg N ha-1, 120 kg N ha-1, 150 kg N ha-1, respectively) with following continuous soil tillage treatments: CT – conventional soil tillage, based on mouldboard ploughing ; DH – multiple pass diskharrowing ; and NT – No-tillage. The chloroplast pigments have been measured in stem extension (after Feekes: 6.0). This research showed that chlorophylls are very sensitive to changes in nitrogen content: concentration of chlorophyll a, chlorophyll b, chlorophyll (a+b) and carotenoids increased with higher fertilization rate. Tillage did not significantly effect on concentration of chloroplast pigments.

The scope of this research was to determine impact of different soil tillage on the morphological parameters (number of branch, pod weight and stem length) and physiological parameters (chlorophyll a, chlorophyll b, chlorophyll a+b and carotenoids) of soybean. The research for soybean has been conducted at the North-eastern Croatia chernozem soil type during the period of 2001/2002–2002/2003, with following continuous soil tillage treatments: CT – conventional soil tillage, based on mouldboard ploughing ; DH – multiple pass diskharrowing ; and NT – no-tillage. The influence of Year was significant for the production of chlorophyll b and carotenoids, while the soil treatment had significant effect on the concentration of chlorophyll (a + b) and chlorophyll b. The interaction Year x Tillage proved to be significant only for concentration chlorophyll b and carotenoids. Agroclimatic conditions significantly affected all the morphological characteristics of soybean, while the effect of tillage was not statistically significant.

The problem of compactness of heavy soils could be surpassed by mole drainage and subsoiling. The aim of this study was to investigate effects of mole drainage and subsoiling (treatment) on available nitrogen content in the soil profile, as well as, its uptake by maize and sunflower, on calcareous clay chernozem soil, in rainfed cropping during 2009. The total N output by plants, leaching and evaporation in control (without mole drainage and subsoiling) was higher by 15% in sunflower and by 43%, in maize. Moreover, N deprivation by leaching and evaporation during the growing season of sunflower was 338.13 kg N ha-1 in control and 287.37 kg N ha-1 in the treatment, while it was 475.03 kg N ha-1 in maize in control and 268.63 kg N ha-1 in treatment. The observed situation affected the plant growth during the growing season – biomass of both, sunflower and maize was higher, but the dry weight was lower in control. The N uptake by crops during the growing season was better in the treatment, resulting in the grain yield increase of 10% in maize and of 9% in sunflower.

There is the strong decline of mouldboard ploughing during transition period from 90% to 60% of arable land in Slovakia due to economic, marketing and environmental reasons. For adoption of environmental sound tillage systems the research and dissemination is needed. The aim of research was to evaluate the influence of conventional and reduced tillage, FYM and residue management on soil bulk density (SBD) and porosity. The field trial was carried out over the period 2004-2006 at the experimental farm PD Kalná nad Hronom in south-western Slovakia. The sugar beet-spring barley- sunflower crop sequence was evaluated. The soil tillage treatments as follows: T1 conventional mould board ploughing with farm yard manure (FYM) application to sugar beet and incorporation of aboveground biomass of growing crops ; T2 conventional mould board ploughing without organic fertilization ; T3 no-till Horsch CONCORD CO 9. During June the soil samples were taken from 0.05-0.10m, 0.1-0.20m, 0.2-0.3m. The SBD and total porosity was highly significantly influenced by growing crops and weather conditions of evaluated years and SBD was also significantly influenced by tillage system. The positive effect of FYM on total porosity was noted in 2004 during sugar beet phase which is in relationship with SBD 1.266 t m3-1.279 t m3 in topsoil layers 0.5-0.20m. In subsequent evaluated years 2005-2006 the topsoil layers 0.5-0.20 m were more compacted with comparison to 2004 after first year of FYM application. In three year average, the conventional mould board ploughing with farm yard manure and incorporation of aboveground biomass form the most suitable soil environment (SBD 1.395 m3, total porosity 43.65%) but we also recommended the no-till (SBD 1.455 m3, total porosity 42.31%) for Haplic Chernozems in this specific area of Slovak region.

This paper presents a computer model to determine land suitability for soil tillage in eastern Croatian based on geostatistical analysis of soil data. As the basis and source of soil types data was used the Croatian soil suitability map in digital form from which used data of soil types and soil chemical analysis data from the interpretative database fertility control of Osijek-Baranja County, a total of 17 341 samples of soil. Presents the model evaluation arable land workability uses a 6 indicators benefits of which three were identified accurately (pH, humus and elevation), and the remaining three are based on Digital Soil Map of Croatian and pedosystemic units whose inherent properties are ranked relative to particular indicators of suitability for soil tillage. Computer simulation using the described models and kriging geostatistical method obtained results showed that 66% of agricultural land belongs to the class of limited suitability for soil tillage (P3), approximately 21% is moderate and very convenient (P2 and P1), and only ~13% belong to the temporary or permanently unsuitable for soil tillage.

In the last centuries, the need for tillage was to provide suitable soil conditions for plant growth (crop-focusing tillage). During the last decades, traditional goals of soil tillage have really been improved considering environmental consequences (environment-focusing tillage). In the next decade a new task is stressed, that is mitigating the climate induced losses (climate- focusing tillage). New challenges for the future is to reduce climate induced damages by the use of environmentally-sound adaptable tillage. The relationship between soil quality factors and climate effects have been studied in parallel in Croatia, in Czech Republic and in Hungary in long term tillage experiments and by field monitoring. In the environmentally- sound tillage challenge ten important steps are suggested for this region, namely: 1) Awareness of the state of the soil to draw conclusions concerning the likely damage. 2) Preventing the development of compact layers impeding water transport. 3) Eliminating the compact layer in the soil with the aid of a suitable tillage technique. 4) Creating small surface at any time of the season, without compaction stress. 5) Covering the surface with crushed stubble residues to protect soil and moisture. 6) Preserving the soil organic C is crucial at any type of tillage. 7) Protecting the soil structure. 8) Adapting the primary tillage to the soil state improvement. 9) Causing smaller stress in over wet or dry soils. 10) Maintaining the soil’s capacity to take in and to store water in irrigated soils.

U novijoj, intenzivnoj poljoprivredi, sve se više vodi računa o održivom razvoju i zaštiti okoliša. Primjeri iz EU pokazuju nam kako je intenzivan razvoj i proizvodnja narušila sklad s prirodom pa su se počele uvoditi mjere i posebni zakoni kako isti ne bi uzeo maha. Novim zakonima u Republici Hrvatskoj kao i EU, posebice bi se utjecalo na tehničke sustave u zaštiti bilja i njihovim obaveznim testiranjima kako bi aplikacija pesticida bila opravdana i ispravna. Jedan od važnih čimbenika aplikacije pesticida je njihovo zanošenje ili „ drift“ . Gubitci ovim načinom iznose do 30 % svih gubitaka aplikacije pa mu treba pridodati više pažnje. Zanošenjem ne samo što imamo novčane gubitke, nego prije svega utječemo i na okoliš. Kapljice pesticida manjih promjera mogu biti daleko odnesene do otvorenih vodenih tokova, naseljenih područja, drugih kultura te tako utjecati na zdravlje ljudi i životinja ili prirod drugih kultura.