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Aim. Alfalfa is a rich source of phytoestrogens, among them coumestrol which shows strong estrogenic activity that can adversely affect the health of domestic animals. The aim of the study was to determine the variation in coumestrol content in leaves of alfalfa breeding populations, present in the breeding program of Agricultural Institute Osijek in Croatia. Method. Twelve alfalfa populations were selected based on their high forage yield and good persistence. Coumestrol was extracted using acidifi ed methanol as an organic solvent from lyophilized and ground alfalfa leaves, while for detection and quantifi cation was used. Results. Signifi cant differences were observed between the studied populations with average coumestrol content of 435.67 mg/kg of dry matter (DM). The highest content of coumestrol was determined in breeding population Rs-21 (619.53 mg/kg of DM). Conclusions. Populations Rs-33 and Rs-20 had the lowest coumestrol content (82.18 and 86.58 mg/kg, respectively) and present a potential breeding source for creat- ing new contemporary cultivars with decreased coumestrol content

Zelena stjenica (Nezara viridula L., 1758) i smeđa mramorasta stjenica (Halyomorpha halys Stål, 1855) su dominantne vrste kukaca iz porodice štitastih stjenica (Pentatomidae) na području Republike Hrvatske dok je ambrozija (Ambrosia artemisiifolia) invazivan i agresivan korov prisutan u čitavoj državi. Cilj istraživanja bio je utvrditi učinkovitost suzbijanja odraslih stadija stjenica vodenim ekstraktom ambrozije. Istraživanje je provedeno u laboratorijskim uvjetima u rujnu 2021. godine u tri tretmana: vodeni ekstrakt ambrozije u koncentraciji 10%, azadiraktin (Ozoneem Trishul® -1%) i voda kao kontrola. Tretmani su postavljeni u četiri ponavljanja te je u pokus ukupno uključeno 240 odraslih jedinki stjenica. Svi tretmani pokazali su blagu toksičnost za ispitivane kukce. Vrsta H. halys bila je osjetljivija na tretman vodenog ekstrakta ambrozije u odnosu na vrstu N. viridula. Statistički značajne razlike mortaliteta odraslih stjenica između tretmana utvrđene su kod vrste H. halys 10 dana nakon tretiranja vodenim ekstraktom ambrozije. Budući da nije utvrđena visoka učinkovitost vodenog ekstrakta ambrozije na odraslim stadijima stjenica istraživanja je potrebno nastaviti i na ličinkama koje imaju viši stupanj osjetljivosti te uz vodene primijeniti i druge vrste biljnih ekstrakata., Southern green stink bug (Nezara viridula L., 1758) and brown marmorated sting bug (Halyomorpha halys Stål, 1855) are the dominant species from the Pentatomidae family in Croatia, while Ambrosia artemisiifolia L. is an invasive and aggressive weed present throughout the country. The aim of this study was to determine the effectiveness of the aqueous ragweed extract in controlling adult stages of stink bugs. The study was conducted under laboratory conditions in September 2021 in three treatments: aqueous ragweed extract at a concentration of 10%, azadiractin (Ozoneem Trishul® -1%) and water as a control. Treatments were set in four replicates and a total of 240 adults stink bugs (120 N. viridula and 120 H. halys) were included in the experiment. All treatments showed mild toxicity. H. halys was more sensitive to the aqueous ragweed extract compared to N. viridula. Statistically significant differences in mortality between treatments were found in H. halys species 10–14 days after treatment with aqueous ragweed extract. Since no high efficacy of ambrosia extract has been found in the adult stage, research will continue on larvae that have a higher degree of sensitivity to aqueous and ethanolic extracts compared to the adult insect stage.

Alfalfa and red clover are important perennial legumes for the production of high-quality fodder. The improvement of the forage quality of legumes is one of the strategic goals of breeding programs. Variation in quality traits (protein content (CP), neutral detergent fiber content (NDF), and acid detergent fiber content (ADF)) and relative feed value (RFV) among seven cultivars and 39 elite breeding populations of alfalfa and red clover was evaluated in the study. Significant differences were determined among the investigated cultivars/populations. Alfalfa populations L-8, 10, 12, 15, and 20 were characterized by a high CP content (up to 23.47%) and/or low NDF and ADF contents. The highest CP content in red clover was recorded in population CD-18 (21.89%), while the lowest NDF and ADF contents were determined in populations CD-19 and CD-4, respectively. High RFV was determined in alfalfa populations L-10, 12, 20, 15, 16, 8, 11, and 17 (prime fodder), and in red clover populations CD-4, 8, 16, 14, and 19 (premium-quality fodder). The identified superior alfalfa and red clover populations will be used to improve the nutritional value of forage crops in our breeding program, which will lead to the release of novel cultivars with improved forage quality.

Allelopathic effect of Aloe vera (L.) Burm.f. on seed germination and seedlings growth of seven plant species was investigated. The experiment was conducted out in Petri dishes and extracts from fresh leaves of A. vera at various concentrations (2, 4, 6, 8, and 10%) were evaluated on germination, seedlings length and fresh and dry weight of seedlings of barley, wheat, soybean, oil pumpkin, radicchio, rocket and lettuce. The effect of water extracts depended on the extract concentration and test species. Extract with concentrations above 2% reduced germination of barley and lettuce seeds, while positive effect was observed on oil pumpkin. The highest decrease of root length was recorded for lettuce by 41.6%, while the root length of oil pumpkin was increased up to 49.9%. Water extracts significantly increased shoot length of wheat, soybean and oil pumpkin. Both positive and negative effects were observed on the fresh weight of test species seedlings, while the dry weight of seedlings was reduced only for barley in all treatments, and for lettuce in the treatment with extract concentration of 4%. Among the test species barley proved to be the most sensitive in all measured parameters, except in root length.

Background: Alfalfa and red clover are the most widespread and most important perennial legumes, primarily used as a high-quality feed for livestock. Both alfalfa and red clover, as well as some other plant species from Fabaceae family, are a rich natural source of phytoestrogens, nonsteroidal compounds with an estrogenic activity whose beneficial effects in the prevention and treatment of many diseases are demonstrated in numerous scientific studies. Objectives: Nowadays, various herbal preparations are present on the world market and their use is constantly increasing, as well as the growing demands of consumers for environmentally sound and health- safe production of plant species used as sources of active substances. Because of their widespread distribution, the possibility of organic breeding, and also significant increases in surface area under genetically modified crops in most EU countries, alfalfa and red clover have become more interesting alternative sources of phytoestrogens. The most common phytoestrogens in these forage legumes are genistein, daidzein, glycitein, formononetin, biochanin, coumestrol, kaempferol and apigenin. The content of these substances is significantly influenced by a number of factors including genotype, environment, production technology, plant maturity stage, and individual plant parts. Conclusion: Available evidence suggests that forage legumes represent high promising sources of health-promoting phytoestrogens. Due to numerous favorable features, they can find commercial application in different industries such as pharmaceutical, nutraceutical, cosmetic, and agriculture.

U radu je istražen alelopatski utjecaj vrste Aloe vera (L.) Burm.f. na klijavost sjemena i rast klijanaca sedam biljnih vrsta. Pokus je proveden u Petrijevim zdjelicama, gdje su procijenjeni ekstrakti svježih listova vrste A. vera u različitim koncentracijama (2, 4, 6, 8 i 10%) na klijavost, duljinu klijanaca te svježu i suhu masu klijanaca ječma, pšenice, soje, uljne bundeve, radiča, rukole i salate. Djelovanje vodenih ekstrakata ovisilo je o koncentraciji ekstrakata i test vrsti. Ekstrakti koncentracije iznad 2% smanjili su klijavost sjemena ječma i salate, dok je pozitivan utjecaj zabilježen kod uljne bundeve. Najveće smanjenje duljine korijena bilo je kod salate i to za 41,6%, dok je duljina korijena uljne bundeve bila povećana do 49,9%. Vodeni ekstrakti povećali su značajno duljinu izdanka kod pšenice, soje i uljne bundeve. Pozitivan i negativan utjecaj utvrđen je na svježu masu klijanaca test vrsta, dok je suha masa klijanaca bila snižena samo kod ječma u svim tretmanima te salate u tretmanu s ekstraktom koncentracije 4%. Među test vrstama, kao najosjetljivija se pokazao ječam kod svih mjerenih parametara, izuzev kod duljine korijena., Allelopathic effect of Aloe vera (L.) Burm.f. on seed germination and seedlings growth of seven plant species was investigated. The experiment was conducted out in Petri dishes and extracts from fresh leaves of A. vera at various concentrations (2, 4, 6, 8, and 10%) were evaluated on germination, seedlings length and fresh and dry weight of seedlings of barley, wheat, soybean, oil pumpkin, radicchio, rocket and lettuce. The effect of water extracts depended on the extract concentration and test species. Extract with concentrations above 2% reduced germination of barley and lettuce seeds, while positive effect was observed on oil pumpkin. The highest decrease of root length was recorded for lettuce by 41.6%, while the root length of oil pumpkin was increased up to 49.9%. Water extracts significantly increased shoot length of wheat, soybean and oil pumpkin. Both positive and negative effects were observed on the fresh weight of test species seedlings, while the dry weight of seedlings was reduced only for barley in all treatments, and for lettuce in the treatment with extract concentration of 4%. Among the test species barley proved to be the most sensitive in all measured parameters, except in root length.

Posavina region represents the area with the most favorable natural conditions for agricultural production in Croatia and Bosnia and Herzegovina. Increase in the air temperature and changes in the amount of rainfall results in changes in evapotranspiration and the values of main water balance elements indicating the need for a precise determination of the current and future state of basic water balance elements, such as soil moisture deficit and the amount of runoff. Linear regression was applied to determine soil water balance response to climate change in Posavina region. The air temperature, precipitation, reference evapotranspiration and water balance components: actual evapotranspiration, total runoff, soil moisture deficit and amount of snow trends were analyzed. Monthly weather data from 4 weather stations, two in Croatia: Slavonski Brod and Gradište ; and two in Bosnia and Herzegovina: Doboj and Gradačac, for the time period of 58 years (1961–2018) were used. The results obtained show increasing trends in annual air temperature (0.032 °C–0.057 °C year−1), sum of precipitation (1.424 mm–2.317 mm year−1), reference evapotranspiration (0.462 mm–4.640 mm year−1), actual evapotranspiration (0.019 mm– 2.190 mm year−1), soil moisture deficit (0.443 mm–2.672 mm year−1) and total runoff (0.286– 2.46 9 mm year−1) series and decreasing trend in the annual amount of snow (0.676–1.664 mm year−1). Results obtained are showing an urgent need to start with climate change adaptation measures and actions to combat the negative impact of climate change in the Posavina region.

In this study, the AquaCrop model was used to quantify climate change impact on yield and net irrigation in maize and soybean production. Daily observed climate data (1961–1990) from Osijek weather station were used for past climate simulation, and output data from ECHAM model were dynamically downscaled under two IPCC SRES scenarios (A1B, A2) for two integration periods 2041–2070 and 2071– 2100. The soil properties and crop data were presented from 6-year-long (2010–2015) a field study of the Agricultural Institute in Osijek, Osijek-Baranja County. The climate results showed an expected rise in air temperature up to 5 ºC and significantly lower precipitation up to 43.5%. According to results from the AquaCrop model, there is no change in maize yield in non-irrigated conditions, while in irrigated conditions there is a yield increase of 1.4 t ha-1 of dry matter (dm), with 80 mm higher net irrigation in comparison with the 1961–1990 period. As for soybean production, the increase in yield is expected in both non-irrigated and irrigated conditions. The yield increases up to 1.9 dm t ha-1 in irrigated conditions with 90 mm higher net irrigation in comparison with the 1961–1990 period. As for crop water indices, in non-irrigated conditions the water use efficiency (WUE) has a trend to decrease in the future, while in irrigated conditions it can slightly increase. Irrigation water use efficiency (IWUE) showed a significantly higher increase in irrigated maize and soybean production.

Cilj rada bio je utvrditi alelopatski utjecaj korovnih vrsta na rast i razvoj usjeva te mogućnost primjene aromatičnih i ljekovitih biljaka u suzbijanju korova. Ispitan je utjecaj biljne mase i sjemena korovnih vrsta: poljski osjak (Cirsium arvense), poljski mak (Papaver rhoeas), bezmirisna kamilica (Tripleurospermum inodorum), oštrodlakavi šćir (Amaranthus retroflexus), crna pomoćnica (Solanum nigrum) i divlji sirak (Sorghum halepense) na pšenicu, ječam, mrkvu, soju i uljnu bundevu. Djelovanje ljupčaca (Levisticum officinale), bosiljka (Ocimum basilicum), prave kamilice (Matricaria chamomilla), matičnjaka (Melissa officinalis), crnoga sljeza (Malva sylvestris) i velikoga rosopasa (Chelidonium majus) utvrđeno je na rast i razvoj korovnih vrsta Teofrastov mračnjak (Abutilon theophrasti), oštrodlakavi šćir, strjeličasta grbica (Lepidium draba), crna pomoćnica, divlji sirak i bezmirisna kamilica. Alelopatski utjecaj ovisio je o korovnoj vrsti, usjevu, koncentraciji, odnosno dozi, biljnome dijelu te stanju biljne mase. U prosjeku su ekstrakti od svih vrsta, osim divljega sirka, smanjili klijavost za više od 20,0%, a rast klijanaca do 41,2% u Petrijevim zdjelicama. Vodeni ekstrakti primijenjeni u posude s tlom smanjili su nicanje i rast usjeva i do 65%. Inkorporacija biljnih ostataka korova u posude s tlom smanjila je nicanje usjeva i do 65,3%. Zajedničko klijanje sjemena usjeva i korova, kao i korijenovi eksudati, nisu pokazali značajan utjecaj na klijavost usjeva. Alelopatski utjecaj aromatičnoga i ljekovitoga bilja također je ovisio o biljnoj vrsti i korovu, koncentraciji i dozi te stanju biljne mase. Pri zajedničkome klijanju sjemena zabilježen je negativan utjecaj na klijanje i do 90,0%. Zajedničko klijanje sjemena u posudama s tlom slabije je djelovalo na korove. Vodeni ekstrakti od svježe i suhe mase smanjili su klijavost i rast korova i do 100%. Biljni ostatci smanjili su nicanje korovnih vrsta i do 60,0% te negativno utjecali na rast klijanaca., The aim of the study was to determine the allelopathic effect of weeds on crop growth and development, as well as the possibility of applying aromatic and medicinal plants in weed control. The effect of biomass and seeds of weed species creeping thistle (Cirsium arvense), field poppy (Papaver rhoeas), scentless mayweed (Tripleurospermum inodorum), redroot pigweed (Amaranthus retroflexus), black nightshade (Solanum nigrum) and johnsongrass (Sorghum halepense) on wheat, barley, carrot, soybean and oil pumpkin was examined. The effect of lovage (Levisticum officinale), basil (Ocimum basilicum), chamomile (Matricaria chamomilla), lemon balm (Melissa officinalis), common mallow (Malva sylvestris) and greater celandine (Chelidonium majus) was evaluated on growth and development of weeds species velvetleaf (Abutilon theophrasti), redroot pigweed, hoary cress (Lepidium draba), black nightshade, johnsongrass and scentless mayweed. The allelopathic effect depended on the weed and crop species, concentration or rate, plant part and plant biomass. On the average, the extracts from all weed species, except johnsongrass, reduced the germination over 20.0% and growth up to 41.2% in Petri dishes. The water extracts applied in the pots reduced the crop emergence up to 65%. In the pots, the incorporation of weed residues reduced the emergence up to 65.3%. The seed cogermination and weed root exudates showed no significant effect on crop germination. The allelopathic effects of aromatic and medicinal plants depended on the plant and weed species, concentration and rate and plant biomass. The cogermination reduced the weed germination up to 90.0%. The seed cogermination showed a lower effect on weeds in the pots. The water extracts from the fresh and dry biomass reduced the germination and growth of weeds up to 100%. The plant residues reduced the weed emergence up to 60.0% and showed a negative effect on the seedling growth.

The aim of the research was to determine the effectiveness of various methods for breaking seed dormancy of weed species Johnson grass (Sorghum halepense (L.) Pers.) and their influence on germination and seedlings growth. Beside control treatment, eight treatments for breaking dormancy of seeds were applied: seed immersion in distilled water for 24 hours ; seed immersion in water at 60 °C for 1 hour ; immersion in a 0.2% solution of potassium nitrate for 24 hours ; immersion in 2% solution of sodium hypochlorite for 8 hours ; treatments with concentrated sulphuric acid for 5 and 10 minutes ; treatment with concentrated sulphuric acid for 5 minutes and germination in darkness ; and combined treatment of sulphuric acid (5 minutes) and 1.5% potassium nitrate solution (2 hours). Average germination of Johnson grass seeds in control treatment was very low, only 2.8%. All dormancy breaking treatments increased seed germination and the highest germination was observed in treatment with combination of sulphuric acid and potassium nitrate (35.0%) and treatment with 2% sodium hypochlorite (30.6%). However, sodium hypochlorite reduced root length of seedlings for 40.9% compared to control, while all treatments had a positive effect on Johnson grass shoot length. Total seedlings length was the highest when seeds were treated for 5 minutes with sulphuric acid. None of the treatments showed significant effect on Johnson grass seedlings fresh weight. Seed germinated fastest in treatment with a combination of sulphuric acid and potassium nitrate (4.58 days), and slowest when seeds were immersed in water (8.16 days) and in the 2% solution of sodium hypochlorite (8.92 days).

The aim of the study was to examine allelopathic effect of marigold (Calendula officinalis L.) on germination and growth parameters of weed species hoary cress (Cardaria draba (L.) Desv.). In total, four experiments were conducted. In Petri dishes, cogermination of hoary cress and marigold seeds, and extracts from fresh and dry marigold biomass in concentrations of 5 and 10% (50 and 100 g per litre of distilled water) were evaluated. In pots with soil, effect of extracts from fresh marigold biomass in aforementioned concentrations and effects of fresh and dry marigold residues in two rates (10 and 20 g/kg of soil) were examined. Cogermination of hoary cress and marigold seeds promoted germination and growth of weed. Extracts from fresh and dry marigold biomass, in Petri dish assay, reduced germination of hoary cress on average for 11.9 and 96.9%. Extracts from fresh biomass promoted shoot length of weed seedlings. On the other hand, extracts from dry biomass strongly inhibited all measured parameters. Higher concentration had greater inhibitory effect. Extracts from fresh marigold biomass applied in pots with soil, had stimulatory effect on weed growth, except for root growth which was inhibited with higher concentration (for 6.6%). Fresh marigold residues incorporated in soil had stimulatory effect on germination and seedling growth of hoary cress. Dry residues also had positive effect, but root length was inhibited for 15.4% with lower and 10.2% with higher rate.

The allelopathic effect of plant species Aloe vera (L.) Burm.f. was evaluated on germination and growth of weeds. Water extracts from fresh leaves in concentrations up to 10% were examined in Petri dish bioassay. Application of water extracts showed no effect on germination of redroot pigweed (Amaranthus retroflexus L.), scentless mayweed (Tripleurospermum inodorum (L.) C.H. Schultz) and velvetleaf (Abutilon theophrasti Medik.), however the highest extract concentration reduced germination of black nightshade (Solanum nigrum L. emend Miller) for 19.6%. Root length of weed species was not affected by extracts, while shoot length, fresh and dry weight of black nightshade, redroot pigweed and velvetleaf seedlings was stimulated. Among weed species, scentless mayweed proved to be the most tolerant.

The aim of the research was to determine the effectiveness of various methods for breaking seed dormancy of weed species Johnson grass (Sorghum halepense (L.) Pers.) and their influence on germination and seedlings growth. Beside control treatment, eight treatments for breaking dormancy of seeds were applied: seed immersion in distilled water for 24 hours; seed immersion in water at 60 °C for 1 hour; immersion in a 0.2% solution of potassium nitrate for 24 hours; immersion in 2% solution of sodium hypochlorite for 8 hours; treatments with concentrated sulphuric acid for 5 and 10 minutes; treatment with concentrated sulphuric acid for 5 minutes and germination in darkness; and combined treatment of sulphuric acid (5 minutes) and 1.5% potassium nitrate solution (2 hours). Average germination of Johnson grass seeds in control treatment was very low, only 2.8%. All dormancy breaking treatments increased seed germination and the highest germination was observed in treatment with combination of sulphuric acid and potassium nitrate (35.0%) and treatment with 2% sodium hypochlorite (30.6%). However, sodium hypochlorite reduced root length of seedlings for 40.9% compared to control, while all treatments had a positive effect on Johnson grass shoot length. Total seedlings length was the highest when seeds were treated for 5 minutes with sulphuric acid. None of the treatments showed significant effect on Johnson grass seedlings fresh weight. Seed germinated fastest in treatment with a combination of sulphuric acid and potassium nitrate (4.58 days), and slowest when seeds were immersed in water (8.16 days) and in the 2% solution of sodium hypochlorite (8.92 days)., Cilj istraživanja bio je utvrditi učinkovitost različitih metoda prekida dormantnosti sjemena korovne vrste divlji sirak (Sorghum halepense (L.) Pers.) odnosno njihov utjecaj na klijavost i rast klijanaca. Uz kontrolni tretman, primijenjeno je osam tretmana za prekidanje dormantnosti sjemena: potapanje sjemena u destiliranu vodu tijekom 24 sata; zagrijavanje u vodi na 60 °C tijekom 1 sata; potapanje u 0,2% otopinu kalijevoga nitrata tijekom 24 sata; potapanje u 2% otopinu natrijevoga hipoklorita; tretiranje koncentriranom sumpornom kiselinom tijekom 5 i 10 minuta; tretiranje koncentriranom sumpornom kiselinom tijekom 5 minuta i naklijavanje u tami, te kombinirani tretman sumporne kiseline (5 minuta) i 1,5% otopine kalijevoga nitrata (2 sata). Prosječna klijavost sjemena divljeg sirka u kontrolnom tretmanu bila je vrlo niska, svega 2,8%. Svi tretmani prekidanja dormantnosti povećali su klijavost sjemena, a najviša klijavost zabilježena je u tretmanu s kombinacijom sumporne kiseline i kalijevoga nitrata (35,0%) te u tretmanu s 2% otopinom natrijevoga hipoklorita (30,6%). Međutim, primjena natrijevoga hipoklorita smanjila je duljinu korijena klijanaca divljeg sirka za 40,9% u odnosu na kontrolu, dok su svi tretmani imali pozitivan utjecaj na duljinu izdanka divljeg sirka. Ukupna duljina klijanaca bila je najviša kod tretiranju sjemena sumpornom kiselinom tijekom 5 minuta. Tretmani nisu pokazali značajan utjecaj na svježu masu klijanaca divljeg sirka. Najbrže je klijalo sjeme u tretmanu s kombinacijom sumporne kiseline i kalijevoga nitrata (4,58 dana), a najsporije kod potapanja sjemena u vodu (8,16 dana) te u 2% otopinu natrijevoga hipoklorita (8,92 dana).

The allelopathic potential of extracts from nine plants species belonging to Asteraceae and Polygonaceae family was evaluated on germination and early growth of lettuce. Water extracts from dry biomass of different plant parts in concentration of 5% were examined under laboratory bioassay in Petri dishes. Among species of Asteraceae family, the highest germination and seedlings growth inhibition was observed with annual fleabane (Erigeron annuus) leaf extract which reduced all parameters for 100%. Similarly, common sow thistle (Sonchus oleraceus) and common tansy (Tanacetum vulgare) also exhibited considerable negative effect. Germination of lettuce was not greatly affected when extracts from Polygonaceae plant species were applied, however significant inhibition of root and shoot length as well as fresh seedling biomass was recorded, especially in treatments with black bindweed (Fallopia convolvulus).

The aim of the study was to examine allelopathic effect of water extracts prepared from fresh biomass of scentless mayweed [Tripleurospermum inodorum (L.) C.H. Schultz] on germination and initial growth of carrot. The experiments were conducted to evaluate: i) the effect of extracts from different plant parts (root, stem, leaf and aboveground biomass) in 1, 5 and 10% concentration in Petri dishes, and ii) the effect of extracts from aboveground biomass in aforementioned concentrations in pots with soil. In Petri dishes, reduction of germination compared to the control was not significant and ranged from 0.5 to 11.1%. Extracts had more pronounced effect on growth and fresh weight of carrot seedlings. Root length was inhibited in all treatments and varied greatly depending on concentration and plant part, while shoot length was both promoted and stimulated. Fresh weight of seedlings was reduced in all treatments and amounted up to 30.5%. Plant parts differed in their allelopathic potential, and root extract exhibited the highest inhibitory effect. In experiment with soil, extracts from fresh mayweed biomass reduced germination for up to 16.1%. Extracts had no significant effect on fresh weight of carrot seedlings, while length of root and shoot were both stimulated and inhibited.

The aim of the study was to determine allelopathic potential of invasive species giant goldenrod (Solidago gigantea Ait.) on germination and initial growth crops (carrot, barley, coriander) and weed species velvetleaf (Abutilon theophrasti Med.) and redroot pigweed (Amaranthus retroflexus L.). Experiments were conducted under laboratory conditions to determine effect of water extracts in petri dish bioassay and in pots with soil. Water extracts from dry aboveground biomass of S. gigantea in concentrations of 1, 5 and 10% were investigated. In petri dish bioassay, all extract concentrations showed allelopathic effect on germination and seedling growth of crops with reduction over 25 and 60%, respectively. Both weed species germination and growth were greatly suppressed with extract application. In pot experiment, allelopathic effect was less pronounced. Reduction in emergence percent, shoot length and fresh weight of carrot were observed. Barley root length and fresh weight were reduced with the highest extract concentration. No significant effect on seedling emergence and growth of A. theophrasti was recorded, while emergence of A. retroflexus was inhibited for 14.4%. Germination and growth of test species decreased proportionately as concentration of weed biomass in water extracts increased. Differences in sensitivity among species were recorded, with A. retroflexus being the most susceptible to extracts.

The aim of the study was to evaluate the effect of six cultivated and wild aromatic and medicinal plants, basil (Ocimum basilicum L.), chamomile (Matricaria chamomilla L.), common mallow (Malva sylvestris L.), greater celandine (Chelidonium majus L.), lemon balm (Melissa officinalis L.) and lovage (Levisticum officinale Koch), on germination and growth of weed species scentless mayweed (Tripleurospermum inodorum (L.) C.H. Schultz). In total four experiments were conducted to assess the allelopathic potential of seed and plant aboveground biomass: I) seed cogermination in Petri dishes, II) seed cogermination in pots with soil, III) water extracts in Petri dishes and IV) plant residues in pots with soil. Weed seed germination was significantly reduced for 32.2% with lovage seeds in Petri dishes. In the pots with soil, seed allelopathic potential was less pronounced. The application of extracts from fresh plant biomass in concentrations of 5 and 10% reduced germination and growth of weed, with the extracts from chamomile and common mallow having the highest inhibitory effect. The extracts from dry plant biomass of basil, chamomile, common mallow, greater celandine and lovage in higher concentration completely (100%) inhibited germination and weed seedling growth. On average, the extracts from dry plant biomass had higher inhibitory effect. Reduction in weed seed emergence and growth was recorded when dry plant residues in rates of 10 and 20 g/kg were incorporated in the soil. Lovage and greater celandine residues exhibited the highest allelopathic effect.

The aim of the study was to determine the influence of different methods on breaking seed dormancy of weed species velvetleaf (Abutilon theophrasti Medik.) and redroot pigweed (Amaranthus retroflexus L.). The influence of seed sowing depth on emergence and growth of weeds was also evaluated. The results showed that the best treatment for breaking seed dormancy of velvetleaf was immersion of seeds in hot water (60°C) for 1 hour, while immersion in distilled water and 0.2% KNO3 solution had no significant effect. Seed germination of redroot pigweed was significantly increased in all treatments, however 2% KNO3 solution and cold stratification at 5oC for 12 days had the greatest effect. Treatments had different influence on mean germination time, seed germination dynamics and seedling length of weeds. The highest percentage of emerged velvetleaf seedlings was recorded when seeds were sown at 1 to 4 cm depths and ranged from 55.6 to 67.9%. With the increase of sowing depth the emergence percentage decreased, however one quarter and one fifth of the seedlings emerged from 7 and 9 cm depths. Both seedling length and fresh weight were greater at lower sowing depths. Emergence of redroot pigweed was not significantly influenced by sowing depth, however seedlings length and fresh weight were greater at 5 cm depth than at 1 cm.

The experiment was conducted to assess allelopathic potential of water extracts from weed species pale persicaria (Polygonum lapathifolium L.) on germination and initial growth of two soybean cultivars (Ika and Sanda). Water extracts from dry stems and leaves of P. lapathifolium in concentrations of 1, 5 and 10% were examined under laboratory conditions using Petri dishes. Results showed that soybean cultivars differed both in their response and sensitivity to allelopathic effect of pale persicaria extracts. Overall, cultivar Ika was more susceptible than cultivar Sanda. On average, germination of soybean was not significantly affected by extracts. The highest germination reduction was recorded with 5% leaf extract for 10.1%. However, Sanda germination was slightly more affected. Contrary, extracts showed greater effect, both stimulatory and inhibitory, on root and shoot length and fresh weight of Ika. Both stem and leaf extracts in 10% concentration had the highest inhibitory effect, up to 48.8%. The increase in extract concentration exhibited higher inhibitory effect, while the lowest concentration generally stimulated soybean growth.

The aim of the study was to examine allelopathic effect of parsley (Petroselinum crispum Mill.) on germination and growth parameters of weed species hoary cress (Lepidium draba (L.) Desv.). Cogermination of hoary cress with parsley seeds, water extracts from fresh and dry parsley biomass in concentrations of 5 and 10% (50 and 100 g per litre of distilled water) were evaluated in Petri dishes. Effect of water extracts from fresh parsley biomass in aforementioned concentrations as well as effects of fresh and dry parsley residues in two rates (10 and 20 g/kg of soil) were examined in pots with soil. Cogermination of seeds stimulated root length, but decreased shoot length and fresh weight of hoary cress seedlings. In the Petri dish assay, extracts from fresh and dry parsley biomass reduced germination of hoary cress, but had both stimulatory as well as inhibitory effect on other parameters. The highest concentration of dry biomass extract completely reduced germination rate of hoary cress (by 100%). In the pot experiment, extracts from fresh parsley biomass had stimulatory effect on weed growth parameters except for root length which was inhibited with higher concentration by 4.2%. Fresh parsley residues reduced germination, root and shoot length of hoary cress, while dry parsley residues promoted measured parameters, with the exception of root length., Cilj istraživanja bio je utvrditi alelopatski učinak peršina (Petroselinum crispum Mill.) na klijavost i rast korovne vrste strjeličaste grbice (Lepidium draba (L.) Desv.). U petrijevim zdjelicama istraživan je učinak zajedničkog klijanja sjemena peršina i strjeličaste grbice te utjecaj vodenih ekstrakata u koncentracijama od 5 i 10% (50 i 100 g na litru destilirane vode). U posudama s tlom ispitivan je utjecaj vodenih ekstrakata od svježe mase peršina u istim koncentracijama te utjecaj svježih i suhih ostataka peršina u dozama od 10 i 20 g/kg tla. Zajedničko klijanje sjemena imalo je stimulativni utjecaj na duljinu korijena, ali je smanjilo duljinu izdanka i svježu masu klijanaca strjeličaste grbice. U pokusima u petrijevim zdjelicama, vodeni ekstrakti od svježe i suhe mase peršina smanjili su klijavost strjeličaste grbice, ali su pokazali i pozitivni i negativni utjecaj na ostale parametre. Najviša koncentracija ekstrakta suhe mase potpuno je inhibirala klijavost grbice (100%). U pokusima s posudama, ekstrakti od svježe mase peršina djelovali su pozitivno na rast korovne vrste, osim na duljinu korijena, koja je bila inhibirana s višom koncentracijom za 4,2%. Svježi biljni ostatci peršina smanjili su klijavost i duljinu izdanka grbice. Suhi ostatci promovirali su klijavost i rast grbice, ali su imali negativan učinak na duljinu korijena.

Cilj istraživanja bio je utvrditi utjecaj kemijskih i bioloških mjera na rast i razvoj presadnica paprike i suzbijanje fitopatogenih gljiva Pythium ultimum i Rhizoctonia solani. Istraživanje je provedeno tijekom 2010. godine u kontroliranim uvjetima (klima komora). Presadnice paprike inokulirane su fitopatogenim gljivama te su primijenjeni sljedeći tretmani: kemijski pripravak Previcur 607 SL (a.t. propamokarb-hidroklorid), biološki pripravak TRI 003 (Trichoderma harzianum - Strain-22), biostimulator Kendal® i kontrola. Primjena biološkog pripravka TRI 003 i biostimulatora Kendal® utjecala je na povećanje mase svježeg lista (20,1 g i 18,9 g) i svježe stabljike presadnica (2,81 g i 2,52 g) te bila viša u odnosu na kontrolu i primjenu kemijskog preparata Previcur. Masa korijena i broj listova presadnica paprike bila je najviša u tretmanu s kemijskim preparatom Previcur. Postotak preživjelih biljaka bio je najviši pri primjeni TRI 003 i Kendal®-a., The aim of this study was to determine the effect of chemical and biological measures on the growth and development of pepper seedlings and the control of phytopathogenic fungi Pythium ultimum and Rhizoctonia solani. The research was conducted in 2010 in controlled conditions (climate chamber). Pepper seedlings were inoculated with phytopatogenic fungi and the following treatments were applied: chemical preparation Previcur 607 SL (a.i. propamocarb hydrochloride), biological product TRI 003 (Trichoderma harzianum - Strain-22), biostimulator Kendal® and control.The application of the biological product TRI 003 and biostimulator Kendal® increased leaf fresh weight (20.1 g and 18.9 g) and stem fresh weight (2.81 g and 2.52 g) and was higher compared to the control and to the treatment in which chemical preparation Previcur was applied. The root weight and the number of leaves of pepper seedling were highest in the treatment with chemical preparation Previcur. The percentage of surviving plants was highest when TRI 003 and Kendal® were applied.

Istraživanje je provedeno u stakleniku u cilju određivanja učinkovitosti bioloških pripravaka u odnosu na kemijske kod suzbijanja Trialeurodes vaporariorum (Westwood) te njihov utjecaj na broj, masu, dužinu i opseg plodova krastavaca. Pokus je proveden tijekom ljetnog i jesenskog vegetacijskog razdoblja, a sastojao se od šest tretmana: Boxer 200 SL (2 ml/2l), Bio-Algeen S-90 (40 ml/2l), Biomit plussz® (40 ml/2l), Agri mix (Agri-50 3 ml/2l +6 ml/2l, naizmjenična primjena), Agri-50 (8 ml/2l) i Agri-50 (6 ml/2l). Svi pripravci primijenjeni su četiri puta tijekom vegetacije. Najbolji učinak pri suzbijanju ličinki T. vaporariorum pokazali su biološki pripravci Biomit plussz® i Bio-Algeen S-90. Agri-50 u svim kombinacijama djelovao je slabije na suzbijanje ličinki u odnosu na kemijski pripravak Bokser 200 SL. S druge strane, u tretmanu gdje je primijenjen Agri-50 u nižoj dozi (6 ml/2l) utvrđeni su najveći broj, masa, dužina i opseg plodova krastavaca u ljetnom uzgoju. U jesenskom uzgoju najbolje djelovanje na krastavce imao je kemijski pripravak Boxer 200 SL i to statistički značajno u odnosu na sve biološke pripravke. Od bioloških pripravaka u jesenskom uzgoju najbolje rezultate na plod krastavaca pokazao je Bio-algeen S-90. Na nizak prinos krastavaca djelovali su i nepovoljni uvjeti uzgoja u jesenskom razdoblju. Iako su svi biološki pripravci pokazali dobar utjecaj na suzbijanje ličinki T. vaporariorum pa i uspješnije od kemijskog sredstva, njihov utjecaj na prinos krastavaca potrebno je dodatno ispitati., The study was conducted in the greenhouse in order to determine the efficacy of biological preparations in comparison whit chemical preparations in the control of Trialeurodes vaporariorum (Westwood) and their impact on number, yield, length and diameter of cucumbers. The trial was conducted during the summer and autumn growing periods and consisted of six treatments: Boxer 200 SL (2 ml/2l), Bio-Algeen S-90 (40 ml/2l), Biomit plussz® (40 ml/2l), Agri mix (Agri-50 3 ml/2l + 6 ml/2l, alternating application), Agri-50 (8 ml/2l) i Agri-50 (6 ml/2l). All preparations were applied four times during the growing season. Biological preparations Biomit plussz® and Bio-Algeen S-90 showed the best effect in supression of T. vaporariorum nymphs. Agri-50 in all combinations was less efficient in suppression of nymphs compared to the chemical preparation Boxer 200 SL. On the other hand, the number, yield, length and diameter of cucumbers in the summer growing period were highest in the treatment with Agri-50 in a lower dose (6 ml/2l). The chemical preparation Boxer 200 SL showed the best results on cucumber fruits in the autumn growing period which were statistically significant compared to all biological preparations. Among biological preparations in the autumn growing season, Bio-algeen S-90 showed the best results on cucumber fruits. The low yield of cucumbers in the autumn growing period was also affected by unfavorable growth conditions. Although all biological preparations showed a good effect in suppression of T. vaporariorum nymphs, some even more successfully than chemical preparations, their impact on cucumber yield needs further study.

Istraživanja su provedena u klima komori na dvije temperature (10 i 20°C), četiri razine pH vodene otopine (4, 5, 6 i 7) sa sjemenom tri kultivara bijele djeteline iste starosti i različitog podrijetla (Regal, Jura i Rivendel). Ispitivan je utjecaj temperature i pH vrijednosti na energiju klijanja, klijavost i dužinu klijanaca kultivara bijele djeteline. Dobiven je značajan utjecaj (p=0,01) svih tretmana na svojstva sjemena i klijanaca. Sva ispitivana svojstva imala su veću vrijednost na višoj temperaturi. Prosječna vrijednost ispitivanih svojstava bila je najveća na pH 5. Kultivar Regal imao je najmanje vrijednosti za sva svojstva. Jura i Rivendel nisu se razlikovali u energiji klijanja i klijavosti, ali je Rivendel imao duže klijance. Reakcija kultivara s obzirom na pH vrijednost imala je isti trend na nižoj temperaturi za sva svojstva. Na višoj temperaturi kultivari su različito reagirali na pH s obzirom na energiju klijanja i klijavost, a podjednako prema dužini klijanaca., The investigations were carried out in a climate chamber at two temperatures (10 and 20°C) and four pH values of water solution (4, 5, 6 and 7) with the seeds of three white clover cultivars of the same age and different in origin (Regal, Jura and Rivendel). We studied the influence of temperature and pH values on energy of germination, germination and seedlings length of white clover cultivars. All the treatments showed significant influence (p=0.01) on the traits of seed and seedlings. All the traits showed higher values at higher temperatures. Mean value of investigated traits was the highest at pH 5. Regal cultivar had the lowest values in all traits. Jura and Rivendel showed no differences in energy of germination and germination, but Rivendel had longer seedlings. Reaction of cultivars in terms of pH values showed the same trend at the lowest temperature in all traits. Cultivars reacted differently to pH at higher temperatures in terms of energy of germination and germination, and about equally in terms of the seedlings length.