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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.

The possible relations between main climate factors and soil state defects have received great attention in the recent years. These factors that are light, temperature, precipitation, and wind have positive and negative impacts on soils. We consider it our duty to assess the main consequences of moisture surplus and water shortage in soils. The third goal of this paper was presenting the combined effect of the climate induced and the tillage induced damages on soil condition. While crop production is one of the sectors adversely affected by climate damage, so steps to prevent and alleviate the deterioration of soils are also drawn up. Five of the important solutions are as follows: 1. Cover the surface to alleviate both the rain and the heat stress mainly in summer. 2. Create surface to be adaptable to water infiltration and water retention. 3. Prevent the pan compaction formation in soils and keep the soil in well- loosened state. 4. Prevent the situations may lead to clod (and dust, crust) formation and use crumb conserving tillage tools. 5. Manage the stubble residues rationally ; residue cover is primary in surface preservation, secondly, the residues are basic source of soil organic matter, and also, food of the earthworms

Based on available literature, practices, and agricultural movements, this study analyzed the conceptualization of agroecology in the West Balkans (Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Serbia, and North Macedonia). For decades, like Yugoslavia, they shared common agricultural development, and agroecology was viewed on a theoretical basis alone. Currently, cooperation exists between agroecology (scientific discipline) and organic agriculture (practical platform). All countries have committed to transition toward sustainable agriculture ; however, lower productivity and economical/structural impediments have resulted in variable acceptance of agroecology. Nevertheless, agroecology is recognized as an alternative approach to conventional agriculture, with the potential to meet future food demands.

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.

Sunflower, along with soybean and oilseed rape, is a very important oilseed crop in Croatia. In the period 1999-2018, it was grown on average of 32, 741 ha with an average grain yield of 2.54 t ha-1. The largest area under sunflower was in 1999 (49, 769 ha) while the highest grain yield was achieved in 2013 (3.20 t ha-1). In general, sunflower production is characterized by significant variations in areas and grain yields, due to number of reasons: agroecological conditions in previous growing season, prices of raw materials and repurchase, incentive and support system, applied technology and knowledge of the producers. However, in the last few years, there has been a slight increase in the areas and sunflower grain yield. Agroecological conditions, choice of hybrids, the possibility of crop rotation expansion, high grain yields in relation to almost all EU countries, processing capacities and repurchase security are in favour of the possibility of more intensive increase of areas and sunflower grain yield in Croatia.

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 Sudan grass plant (Sorghum bicolor (L.) Moench subsp. drummondii) density and yield were determined in this 2-year research with different tillage systems and fertilization at 3 locations. After harvesting the main crops, 3 tillage treatments were applied: conventional (CT) mouldboard ploughing (25-30 cm deep), followed by disk harrowing and sowing: reduced tillage 1 (HDH) with 2 passes by a disk harrow (15-20 cm deep), followed by seedbed preparation, and reduced tillage 2 (LDH) with a single pass by a disk harrow. Soil penetration resistance was measured at each tillage treatment. A total of 5 side dressing fertilizer treatments were applied: the control (NO), calcium ammonium nitrate (CAN) 100 kg ha-1 in granular form, 60 kg ha?1 urea applied as foliar fertilizer (UF), 8 L ha-1 of foliar fertilizer Profert Mara (0.9 kg N, 0.22 kg P, 0.38 kg K, 0.24 kg Ca, 0.01 kg S, and 0.03 kg Mg) (PM1), and double rate PM1 (PM2). Significant differences (P ≥ 0.05) among the tillage treatments were present (19.023, 18.934, and 17.489 t ha-1 of dry matter for CT, HDH, and LDH, respectively). The tillage treatments resulted in significant differences (P ≥ 0.05) in the average plant density in both experimental years, with the greatest plant number with HDH (104.11 m2) and highest soil penetration resistance value with CT (more than 2.00 MPa). All of the fertilizer treatments resulted in a higher yield than the control (14,698 kg ha-1). CAN, UF, and PM1 were not different among themselves, whereas PM2 resulted in significantly higher dry matter yield. The results suggested better effects of foliar than granular fertilizers for postharvest-sown Sudan grass in the drought of 2009 or the over-wet conditions of 2010.

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 tillage systems were compared in soybean production on one experimental field (chernozem) located in the Baranya region of Croatia over a 4-year period (2001/2002, 2002/2003, 2003/2004, 2004/2005). The dry conditions experienced in 2003 exacerbated the effects of NT and CWNS on the soybean yield. The most stable grain yield was obtained using CSNW and CSDW in all four experimental years. DH, CH and CWDS did not result in any significant reduction in crop yield compared to CT. There was no clear trend regarding the applied tillage systems and grain yield components. The greatest effects on soybean yield and yield components were due to climatic conditions. Different tillage systems had a significant effect on the soybean grain yield and yield components in the four experimental years. The largest differences in stem height were determined between CSNW and NT. The number of pods per plant, the hectolitre mass and the grain yield were significantly lower under NT than under the other tillage systems. The number of fertile nodes of soybean and the number of branches per plant in the experimental years had approximately the same values for all the tillage systems. To sum up, the results achieved with DH, CH, CSDW, CWDS and CSNW were on par with each other and slightly better than CT, and these systems could represent adequate replacements for conventional tillage. No tillage could not be considered as the most favourable for soybean growing.

The optimal planting terms, which contain favorable conditions for emergence and early growth, are one of the most important preconditions for achieving high grain yields. During this period, the most important environmental factors are temperature and soil moisture, which have a key role for optimal conditions needed for the young plants genotype potential expression. Beside genetic specificities which are preconditioning plant's growth and development, the seed size is one of the very important biological factors which has strong influence at faster sprouting and intensive growth within the heterotrophic stage, when seed reserves have the key role for supplying young plant with the nutrients. The tolerance of the maize hybrids at suboptimal temperatures which can frequently occur in early spring has been observed by Szundy et al. (2005) through the number of days to emergence and individual dry shoot mass. According to Pommel et al. (1995), plants developed from greater seed had higher leaf area if compared with plants from smaller seed. Gilbert et al. (1995) concluded that the dry weight of plants shoot and root is positively correlated with the seed size. Batistella et al. (2002) found out in their research that there were significant differences between hybrids and seed category and their influence at shoot and root length, together with shoot dry weight in favor of larger seed fractions. After Grzesiak (2001) smaller ratio of shoot and root length is indicating higher hybrid resistance on the induced stress. The aim of this research was to determine the influence of the temperature, genetic specificity and seed size fractions at phenologic and physiologic features of the maize in early growth.

The objectives of this experiment were to determine the chloroplast pigments dynamics of soybean leaves during the growth stages under different tillage systems, which can be a major factor limiting yield of soybean. The greatest differences between the photosynthetic productivity parameters of the investigated soybean were determined from reproductive stages (R2 and R3 – 4). The chlorophyll a, chlorophyll a/b and carotenoids content under CT, DH and NT were greater in the reproductive stages (R2 and R3 – 4) than in the early stages (V3 – 4 and R1). The concentration dynamics of chlorophyll b and chlorophyll a/b was very similar in all growth stages and under all tillage systems in the 2-yr average. The increased drought stress in 2003 was likely critical in the observed lower seed yields in 2003. The yield of soybean was significantly lower under NT than CT and DH treatments in both years. The relationship between the soybean yield and chloroplast pigments concentration is strongly influenced by external...

U radu je predstavljen model interpretacijske baze zemljišnih resursa Osječko-baranjske županije koja, nakon 10 godina provođenja projekta „Kontrola plodnosti tla na obiteljskim poljoprivrednim gospodarstvima“, obuhvaća površinu oko 75 000 ha, sadrži ~ 25 000 slogova i više od 1 000 000 podataka, odnosno informacija. Model je podržan originalnim računalnim programom (ALRxp) za utvrđivanje relativne pogodnosti poljoprivrednog zemljišta za usjeve, potrebe za kalcizacijom ili drugim vidom popravaka nepovoljnih fizikalno-kemijskih svojstava i izračun gnojidbene preporuke za konkretni usjev u sustavu konvencionalne, integrirane i ekološke proizvodnje. Automatska interpretacija rezultata temelji se na 50-ak ekspertnih pravila koja omogućavaju proračun potreba u gnojidbi i u narednom periodu za šest najzastupljenijih usjeva u Republici Hrvatskoj te i procjenu N-mineralizacije. Rezultati proračuna zajedno sa svim podacima spremaju se u izlaznu bazu (iBazu) namijenjenu geostatističkoj analizi poljoprivrednog prostora i vizualiziraju na tematskim kartama uz mogućnost online i offline pristupa svim podacima., This paper presents an interpretive base model of land resources of the Osijek-Baranja County. After 10 years of conducting the project “Control of soil quality on family farms” the base, covering an area of about 75 000 hectares, containing ~ 25 000 records and more than one million land data were created. The model is supported by an original computer program (ALRxp) which can determine the relative suitability of agricultural land for crops, the need for liming or other type of repairs like physical and chemical properties of soil and also calculate fertilizer recommendations for specific crops in conventional, integrated and organic agricultural production. Automatic interpretation of results is based on 50 expert rules which allow the calculation of fertilizer recommendations for upcoming period of six most represented crops in the Republic of Croatia and also the assessment of N-mineralization. The model results together with all other land data are stored in the so-called output base (iBase) which is ready for geostatistical analysis of the agricultural land and visualization on thematic maps with the possibility of online and offline access to all data.

Podlanak (kamelina, lanolik, Camelina sativa) uljarica je čiji je uzgoj itekako zanimljiv zbog visokokvalitetnog ulja, no i zbog drugih funkcija koje može ispuniti (pokrovni usjev, siderat, krmivo, bio-masa, pčelinja paša). Istraživanje uzgoja podlanka u egroekološkim uvjetima kontinentalne Hrvatske provedeno je u 2013. godini na trima lokacijama (Poljanci- ritska crnica, Široko Polje-eutrično smeđe tlo, Vraneševci-lesivirano tlo-luvisol), na kojima su s pomoću split-plota u četiri ponavljanja ispitani glavni tretman "Obrada" u trima razinama (CT-obrada tla oranjem ; MD-reducirana obrada višestrukim tanjuranjem ; SD-reducirana obrada jednostrukim tanjuranjem) i podtretman "Gnojidba" u sedam razina (GO-kontrola, bez prihrane ; G1-standardne prihrane KANom ; G2- prihrane 5%-tnom otopinom Uree ; G3-folijarna prihrana pripravkom "Profert Mara" ; G4- folijarna prihrana pripravkom "Profert NGT" ; G5-prihrane mikrobiološkim preparatom Thiofer ; G6-prihrane mikrobiološkim preparatom EM Aktiv). Prinosi zrna podlanka s obzirom na količinu i tip ishrane, tip obrade i zaštitu kretali su se od 686 do 1178 kg ha-1. Prinosi suhe biomase kretali su se od 3657 do 6566 kg ha-1. Urod zrna i biomase bio je najviši pri upotrebi EM aktiva za kamelinu, neovisno o primjenjenoj agrotehnici.

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 trial with different side-dressing fertilizations for winter wheat has been conducted at Vetovo site, Croatia, in vegetation seasons 2007/08 and 2008/09. The five side-dressing fertilizations has been tested (Control - no sidedressing, KAN - 100 kg KAN ha-1 in tillering and jointing stages; M1 - 8 l of foliar NPK fertilizer 'Profert Mara' ha-1; M2 - 16 l ha-1 of foliar fertilizer, and; M3 - 24 ha-1 of foliar fertilizer) at four winter wheat cultivars (Anika, Fiesta, Gabi and Rapsodija), with previously applied 400 kg NPK 7:20:30 ha-1 for all treatments. Results showed that all foliar side-dressing treatments gave winter wheat grain yield higher than the control, and that M1 treatment showed equal in comparison with KAN side-dressing. Treatments M2 and M3 had, in comparison with the control, KAN and M1 treatments, higher yields which leads toward conclusion that foliar treatments can be recommended for side-dressing for given agroecological conditions. Istraživanje sa različitim načinima prihrane ozime pšenice sproveden je u vegetacijskim sezonama 2007/08. i 2008/09. na lokalitetu Vetovo, Hrvatska. Testirano je pet tretmana prihrane (Kontrola - bez prihrane; KAN - po 100 kg KAN ha-1 u busanju i vlatanju; M1 - 8 l folijarnog NPK gnojiva 'Profert Mara' ha-1; M2 - 16 l ha-1 folijarnog gnojiva. te; M3 - 24 ha-1 folijarnog gnojiva) na četiri sorte ozime pšenice (Anika, Fiesta, Gabi i Rapsodija) uz prethodnu osnovnu gnojidbu za sve varijante od 400 kg NPK 7:20:30 ha-1. Pokus je pokazao da su svi tretmani folijarne prihrane dali urod viši od kontrolnog tretmana, te da se tretman M1 pokazao ravnopravnim u odnosu na prihranu KAN-om. Tretmanom M2 i M3, u odnosu na tretmane Kontrola, KAN i M1, signifikantno su povećani prinosi ozime pšenice, iz čega proizlazi da se folijarni tretmani mogu preporučiti u danim agroekološkim uslovima.

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.