Search

The aim of the paper was to evaluate the influence of water stress i.e., different net irrigation water on the allelopathic potential of petunia (Petunia hybrida L.). Water extracts were prepared from aboveground biomass of petunias grown at different net irrigation water (51.5 mm, 91.5 mm and 132.5 mm) in three concentrations (1%, 2.5% and 5%). The experiment was performed under controlled laboratory conditions in Petri dishes and the allelopathic potential of petunia water extracts was assessed by measuring seed germination, root and shoot length, and fresh weight of radish seedlings. The results of the experiment showed a statistically significant allelopathic effect of petunia water extracts on all the measured parameters. The allelopathic potential largely depended on the extract concentration. Petunia extracts of higher concentrations showed a greater negative effect and reduced germination, shoot and root length, and fresh weight of seedlings up to 79.9%, 93.4%, 83.1% and 69.5%, respectively. Positive effect was determined on shoot length and fresh weight of radish seedlings with 1% concentration extracts. As a rule, water stress i.e., net irrigation water did not have a significant effect on the allelopathic potential of petunia. The exception was recorded with the highest extract concentration on the shoot length of seedlings where extracts from petunias grown at 51.5 mm had greater inhibitory effect compared to extracts from petunias grown at 91.5 and 132.5 mm.

Primjena plazma tehnologije u poljoprivredi provodi se tretiranjem sjemena ili biljaka hladnom plazmom (NTP) ili plazmom aktivirane vode (PAW). Različit reaktivni spojevi potencirani plazmom djeluju kao signalne molekule u metabolizmu biljaka, pokreću aktivnost gena koji reagiraju na stres u biljkama ili služe kao hranjive tvari. Cilj ovoga rada je prikazati učinak tretiranja hladnom plazmom na promjene koje dovode do poboljšanja rasta poljoprivrednih kultura. Rezultati istraživanja ukazuju na različiti odgovor poljoprivrednih kultura na tretman plazmom. Zbog toga je potrebno provoditi daljnja istraživanja kako bi se utvrdio optimalan utjecaj plazme na biljke.

Spavanje predstavlja biološki proces nužan za očuvanje zdravlja i obavljanje svakodnevnih funkcija. Doktori dentalne medicine često su prvi među zdravstvenim djelatnicima koji primijete simptome poremećaja spavanja ili im se pacijenti sami požale na njih. Stanja poput sleep apneje, bruksizma i orofacijalne boli ozbiljno narušavaju pacijentovu kvalitetu života i dovode do teških posljedica. Poremećaji spavanja zahtijevaju multidisciplinaran pristup, a veliku ulogu u ranom prepoznavanju, prevenciji i terapiji imaju doktori dentalne medicine. Pri tome je potrebno razumjeti neurobiološke mehanizme u podlozi patoloških zbivanja povezanih s poremećajima spavanja i disanja, razjasniti neuromuskularnu povezanost žvačnog sustava, prepoznati etiološke i rizične faktore te pružiti pacijentima odgovarajuću terapiju u suradnji s drugim medicinskim djelatnicima. Sleeping is a biological process essential for preserving health and carrying out everyday bodily functions. Dental practitioners are often the first health workers to detect – or hear patients complain of – symptoms of sleeping disorders. Conditions such as sleep apnea, bruxism, or orofacial pain can seriously impact a patient’s quality of life and may lead to serious complications. Treating sleep disorders requires a multidisciplinary approach in which dental practitioners play a vital role in early detection, prevention, and treatment. This demands an understanding of the neurobiological mechanisms that underlie pathological occurrences connected with sleep disorders and breathing, a clarification of the neuromuscular coherence of the masticatory system, an identification of etiological and risk factors, and the right treatment in cooperation with other medical practitioners.

Biostimulants are substances that are applied to plant or soil may enhance plants ability to assimilate applied nutrients which results with better development. The aim of this study was to evaluate the effect of biostimulants (Amiksol and Slavol), applied with an organic fertilizer (Stallatico) on the yield and morfological characteristics of strawberry (Fragaria x ananassa Duch.) cultivar Clarity. An experiment was carried out in the 2021 in the open field as a complete randomly design with four replicates, and treatments were: Stallatico (Control), Stallatico + Slavol (T1) and Stallatico + Slavol + Amiksol (T2). Morphological properties were measured in four terms of vegetative growth and fruiting. Twenty plants were selected randomly from each experimental unit to measure the length of canopy (cm), length of roots (cm), total length of plant (cm), as well as weight of canopy (g), weight of roots (g) and total weight of plant (g), number of leaves and stolon and yield (number and weight of fruits). Data were processed by ANOVA and LSD was detrmined at P

U radu su prikazani rezultati istraživanja analize održavanja poljoprivredne tehnike u eksploataciji. Obavljen je intervju sa rukovateljima (81) koji upravljaju s istraživanom poljoprivrednom tehnikom, a u vidu utvrđivanja provođenja mjera dnevnog i tjednog održavanja. Mjere dnevnog održavanja se u većem dijelu ne provode, a što je suprotno od mjera tjednog održavanja koji se većim dijelom provode. Rukovatelje istraživanih strojeva treba potaknuti i po potrebi poslati ponovno na edukacije kako bi kvalitetnije obavljali mjere održavanja i s time produžili radni vijek poljoprivredne tehnike.

Republika Hrvatska ima pogodne uvjete za proizvodnju hrane, no trebali bismo biti puno uspješniji. Kao sastavnica Europske unije imamo na raspolaganju veliko tržište kojemu se treba konkurentnošću i kvalitetom nametnuti. Naši najveći potencijali su voda, tlo i povoljna klima. Sretna je okolnost da imamo prirodnih oborina tijekom vegetacije više od polovine potreba tako da je navodnjavanje dopunskoga karaktera. Naše veliko bogatstvo su i tla kojih obrađujemo oko 1, 500.000 ha, a oko 600.00 ha treba ponovno privesti kulturi (prije su bila obrađena). Od navedenih poljoprivrednih površina kategorija oranica i vrtova ima preko 800.000 ha. U Hrvatskoj se trenutno navodnjava oko 35.000 ha iako imamo infrastrukturu za veću površinu. Od 2005. godine aktualan je nacionalni projekt navodnjavanja, NAPNAV koji je intenzivirao navodnjavanje i bolje korištenje vodnih i zemljišnih resursa. Još uvijek se pravi dosta pogrešaka pri navodnjavanju poljoprivrednih kultura, a cilj nam je predložiti rješenja. No, svladavanjem najvažnije prepreke, a to je educiran i savjestan poljoprivrednik će se puno lakše svladati i brojne druge poteškoće. Važan cilj nam je postići samodostatnost u proizvodnji hrane odnosno u što više poljoprivrednih proizvoda. Cilj ovoga rada je ukazati na potencijale i poteškoće u poljoprivredi kao bismo naučili više i bili učinkovitiji.

Field pea (Pisum sativum L.) is one of the most important protein legumes. It is considered one of the four most important cultivated large-seeded pulses. Although grain yield is the most important breeding trait, the focus of the breeding process is also directed at other quantitative traits (yield components). The study of genotypes (breeding lines) in different environments through the analysis of the most significant quantitative properties, as well as the assessment of their interaction values, contributes to the creation of new sources of genetic variability and new genetic material (varieties/hybrids). The study goals were: to evaluate the agronomic value of nine newly created spring breeding lines of fodder pea during two consecutive years (2019 and 2020), to evaluate the stability of yield components and to select the most promising genotypes for further breeding procedure based on the obtained results. The results of the study showed that there are significant differences between the tested genotypes in the tested environments for most of the analysed properties and that the variation of genotypes has the greatest influence within the identified sources of experimental variation. The stability assessment was made by the grouping method according to Francis and Kannenberg, based on which the values of the genotypes L – OSMBK 1, L – OSMBK 3 for grain/plant yield L – OSMBK 1, L – OSMBK 8, L – OSMBK 3, L – OSMBK 9 for 1000 seed weight and L - OSMBK 9 for the plant height were in group I, which is characterized by high values and a small coefficient of variation of properties and represents the most stable and most promising breeding genotypes.

Zinnias are ornamental species which are not demanding for breeding, sunny and warm position with loamy well-drained soil is sufficient. The aim of the research was to compare the growth and development of Zinnia (Zinnia elegans Jacq.) in a sunny place, during spring and summer period, in three substrates of various physical and chemical properties (Potgrond H, Florabella and soil). The seeds were sown in PVC containers (Pöpellmann TEKU (EP 2128/20) 28 cm x 21cm x 6 cm) with 20 sowing places (volume 150 ml). After developing four leaves, plants were transplanted into PVC pots (Φ 9 cm) filled with the same substrate. The pot trial was conducted as a randomized complete design with four repetitions. Four weeks later on the developed plants, following values has been measured: plant mass, plant height, plant height above ground, mass of the above-ground part of the plant and the number of leaves. Plants grown in Florabella substrate had higher values than plants grown in Potgrond substrate and soil. Statistically significant difference (P≤0.01) has been found between the values of plants grown in soil and substrates Potgrond H and Florabella.

Uzgoj brzorastućih biljnih vrsta osigurava nove energetske izvore koji omogućuju zaštitu šuma od sječe i posredno ublažavaju postojeće klimatske promjene. Paulovnija je drvenasta biljka značajna za proizvodnju biljne biomase koju odlikuje brzo klijanje, rast i razvoj velike količine lisne i drvenaste mase u kratkom uzgojnom periodu. Radi brzine rasta i formiranja stabla ujednačene debljine, pogodna je za preradu te je jedna od osnovnih sirovina u drvoprerađivačkoj industriji, ali i za upotrebu u energetske svrhe. Međutim, u početnim fazama rasta i razvoja, paulovnija je osjetljiva na povećanu vlažnost koja uzrokuje pojavu bolesti, štetnika i propadanje biljke. Stoga se, kod uzgoja presadnica paulovnije radi prevladavanja potencijalnog stresa i osjetljivosti na vodni režim preporučuje upotreba biostimulatora. To su fiziološke aktivne tvari koje biljkama pomažu pri rastu i razvoju, te smanjuju štetne posljedice nastale od suše, smrzavanja, mehaničkih i kemijskih oštećenja kao i od infekcija biljaka. Cilj ovoga istraživanja bio je utvrditi utjecaj primjene biostimulatora Delfan Plus® u različitom vremenskom periodu na rast i razvoj hibrida paulovnije Shan Tong (Paulownia fortunei × Paulownia tomentosa) iz „in vitro“ proizvodnje. Pokus je postavljen sa sadnicama koje su prihranjivane s biostimulatorom Delfan Plus® u količini 8 ml/10 l vode. Tretiranje biostimulatorom je obavljeno u tri varijante: prihrana biostimulatorom svakih 7, 14, 21 dana te kontrolna varijanta (bez primjene biostimulatora). Tijekom praćenja rasta i razvoja paulovnije, u periodu od jedanaest tjedana određivana je visina sadnica, a na kraju pokusa broj listova, masa listova (g), masa suhe tvari listova (g), masa suhe tvari stabljika (g), duljina korijenja (cm), masa svježe tvari korijenja (g) i masa suhe tvari korijenja (g). Rezultatima istraživanja utvrđen je najveći porast nadzemnog dijela biljaka kao i veći broj listova nakon tretiranja s biostimulatorom svakih 14 dana. Ove sadnice imale su čvršći i razvijeniji korijen za razliku od sadnica s ostalim tretmanima biostimulatorom. Najbolja iskoristivost svih elemenata sadržanih u biostimulatoru uočena je na vanjskom izgledu sadnica koje su bile zdravog izgleda bez pojave bolesti i štetnika. Rezultati istraživanja potvrđuju da primjena biostimulatora olakšava i ubrzava proces uzgoja sadnica paulovnije namijenjenih u komercijalne svrhe., Paulownia is an exotic, ornamental and decorative woody plant originating from China, and in terms of agrotechnical cultivation and use, it is important for plant biomass production. The plant characteristics are rapid germination, plant growth, development of large amounts of leaf and woody mass in a short vegetation period. Due to fast growth and the formation of uniform thickness trees, paulownia is suitable for processing and one of the basic raw materials in the wood industry, but it is also suitable for energy production. However, in paulownia initial stages of growth and development, sensitivity to increased humidity was determined, which causes the appearance of diseases, pests and plant decay. In order to overcome the potential stress and sensitivity to the water regime in initial stages of transplants development, the use of biostimulants is recommended. Biostimulants are physiologically active substances that help in plant growth and development, reduce the harmful consequences of drought, freezing, mechanical and chemical damage and the consequences of plant infections. The aim of this study was to determine the application impact of biostimulants Delfan Plus® in different time periods on the growth and development of hybrid ʹShan Tongʹ (Paulownia fortunei × Paulownia tomentosa) transplants from "in vitro" production. In study, transplants were treated with the biostimulants in the amount of 8 ml/10 l of water. Plants were treated in three different variants: treating every 7, 14, 21 days and the control (without treating) was performed. During the monitoring of transplants growth and development in a period of eleven weeks, the height of the plant (cm), number of leaves and the length of the roots (cm) were measured. The research results determined the largest increase in the height of the plants, as well as a larger number of leaves after biostimulants treating used every 14 days. These transplants had a firmer and more developed roots in contrast seedlings in other treatments. The best utilization of all biostimulant elements was observed on transplants that were healthy looking without the appearance of diseases and pests. The obtained results indicate that use of biostimulants enhance process of growth of paulownia transplants intended for commercial purpose madding the process easier and faster.

Shema uređenja gradilišta je tlocrtni grafički prikaz razmještaja svih sadrţaja na gradilištu. Potrebna je za organizaciju radnih procesa na gradilištu koji se trebaju odvijati u planiranim rokovima na što ekonomičniji način. Elementi uređenja gradilišta su privremene zgrade i naselja potrebni za privremeni smještaj i rad ljudi, skladišta i deponije za privremeno odlaganje materijala i strojeva, gradilišni pogoni (npr. betonare, tesarski pogon), vanjski i unutarnji transport, te opskrbe strujom i vodom. Elementi uređenja gradilišta najčešće su privremenog karaktera, iako postoji mogućnost korištenja već postojećih ili izgradnje novih koji trajno ostati kao dio buduće građevine (navesti primjer elemenata koji mogu trajno ostati kao dio buduće građevine). Prilikom dimenzioniranja i razmještaja elemenata vaţno je paziti na smjernice i drţati se pravila i principa uređenja gradilišta, kako bi postigao optimalni raspored resursa na gradilištu i zaštita ljudi i okoliša.U okviru ovog završnog rada opisani su osnovni elementi uređenja gradilišta s proračunom kapaciteta – smještaj materijala, ljudi, prerada materijala. Na primjeru obiteljske kuće izrađena je shema uređenja gradilišta za fazu izvođenja pripremnih, zemljanih, betonskih i zidarskih radova.

Maize (Zea mays L.) grain yield largely depends on the amount of plant-available water, nutrients, climatic conditions, soil, and genotype. The grain yield formation is closely related to yield components. The field study was set up near Osijek (2020) on silty clay soil with, loamy texture. The different treatments consisted of two irrigation treatments (a1=irrigated ; a2=rainfed), and two maize hybrids (b1=ossk515 ; b2=po216). Surface irrigation was conducted with the use of furrows, while the soil water content was measured with tensiometers placed at a depth of 30 cm on each irrigation treatment. Net irrigation was 280 mm which completely compensated the crop water requirements on irrigated plots. Significantly (p

The COVID-19 pandemic has significantly affected many segments of human life and activities, including the education system. As a consequence, universities are facing challenges on how to continue with quality teaching where face-to-face classes have opted and remote teaching is introduced. Remote teaching and learning usually carry a stigma of being lower quality than the traditional (face- to-face), which is why it is necessary to evaluate the teaching staff as well as the student experience within remote education. The survey conducted at the Faculty of Agrobiotechnical Sciences Osijek, Republic of Croatia aimed to analyze how students as well as teaching staff were satisfied with remote education during the first wave of coronavirus pandemic. Survey results have shown that most of the students were satisfied with the organization and implementation of remote learning and teaching as well. An interesting observation was the importance of teacher- student interaction as well as the teacher presence during remote education.

Cilj istraživanja bio je utvrditi utjecaj vodnog stresa odnosno različitih normi navodnjavanja na alelopatski potencijal salate (Lactuca sativa L.). Pokus je proveden u Petrijevim zdjelicama prema potpuno slučajnom planu s tretmanima u šest ponavljanja u kontroliranim laboratorijskim uvjetima. Alelopatski potencijal vodenih ekstrakata pripremljenih od listova salate uzgajane pri različitim normama navodnjavanja (45 mm, 90 mm i 135 mm) testiran je u tri koncentracije (2, 5 %, 5 % i 10 %) na klijavost sjemena i rast klijanaca rotkvice. Alelopatski utjecaj procijenjen je mjerenjem klijavosti sjemena, duljine korijena i izdanka, te svježe mase klijanaca rotkvice. Alelopatski potencijal vodenih esktrakata salate ovisio je o normi navodnjavanja i koncentraciji. Povećanjem koncentracije vodenih ekstrakata povećavao se negativni alelopatski utjecaj, te je zabilježeno potpuno inhbitorno djelovanje (100 %) na klijavost i rast klijanaca rotkvice u tretmanima s ekstraktima najviše koncentracije. Vodni stres uzrokovao je veći negativni alelopatski potencijal. Vodeni ekstrakti koncentracije 5 % pripremljeni od salate uzgajane pri dvije niže norme navodnjavanja od 45 mm i 90 mm imali statistički značajno jače inhibitorno djelovanje od ekstrakata salate uzgajane pri normi navodnjavanja od 135 mm na sve mjerene parametre.

With the increasing need for energy, energy studies to be obtained from waste gain importance. In this study, it has been tried to determine the amount of biogas energy that can be obtained from olive pomace (pirina), which is produced by processing oil olives. Numerical maps of pirina amounts and potential biogas energy values and location maps of the proposed pirina processing plant were created. The necessary calculations were made by comparing the obtained results with the relevant literature information. In the study, the current potential biogas energy amount was calculated, maps were created and the electricity and gasoline energy equivalent levels of this energy were tried to be calculated using the 2015-2019 data of the Mediterranean, Aegean and Marmara Regions. The total potential amount of pirina in the research area is 1853375.7 tons and the potential biogas energy amount that can be obtained is 33360762.4 MJ. Pirina, which is the production waste after pressing the olives for oil, can be used for energy production. By using pirina to obtain biogas energy, both the utilization of pirina and the development of the regions will be provided.

Maize seed is during germination and cropping in the open under the influence of different agroecological factors, so high yields will be achieved mainly by sowing quality high vigor seeds. The aim of this research was to determine maize seed vigor by laboratory methods (mass of 1000 seeds, germination energy (GE), standard germination (SG), electrical conductivity (EC) and cold test (CT)) and at the same time examine the influence of genotype of three maize hybrides. The experiment was set up in four repetitions with 50 seeds for each method. A significant difference (P≤0.01) was found between the masses of 1000 seeds of the analyzed hybrids (314g, 307g, 252g). The energy of germination (66%, 63%, 61%), standard germination (94%, 95%, 91%) and cold test (87%, 97%, 83%) did not differ significantly. The determined values of electrical conductivity (7,96 μScm-1g-1, 7,16 μScm-1g-1, 5,23 μScm-1g-1) were significantly (P≤0.01) influenced by hybrids. The analyzed seed was of satisfactory quality or vigor, and the influence of genotype was determined in seeds tested by electrical conductivity method., Sjeme kukuruza je tijekom klijanja i nicanja na otvorenom pod utjecajem različitih agroekoloških faktora pa se visoki prinosi mogu postići prije svega sjetvom kvalitetnog sjemena visokog vigora. Cilj ovoga istraživanja bio je odrediti vigor sjemena kukuruza laboratorijskim metodama (masa 1000 sjemenki, energija klijanja, standardna klijavost, električni konduktivitet i cold test) te ujedno ispitati utjecaj genotipa tri hibrida kukuruza. Pokus je postavljen u četiri repeticije s 50 sjemenki za svaku metodu. Utvrđena je značajna (P≤0,01) razlika između masa 1000 sjemenki analiziranih hibrida (314g, 307g, 252g). Energija klijanja (66%, 63%,61%), standardna klijavost (94%, 95%, 91%) i cold test (87%, 97%, 83%) nisu se značajno (P≤0,01) razlikovali. Utvrđene vrijednosti električnog konduktiviteta (7,96 μScm-1g-1, 7,16 μScm-1g-1, 5,23 μScm-1g-1) bile su pod značajnim (P≤0,01) utjecajem hibrida. Analizirano sjeme imalo je zadovoljavajuću kvalitetu odnosno vigor, a utjecaj genotipa utvrđen je kod sjemena testiranog metodom električnog konduktiviteta.

Marigold (Tagetes spp.) is present in every garden because it is not a demanding plant. Carrot (Daucus carota L.) is one of the ten most important garden vegetables which prefers acid to neutral soils and airy one. The aim of this research was to determine differences in growth and development of French Marigold in two growing media (soil type Eugley and substrate) and to determine quality properties of carrot growth in two different soils (Luvisol and Eugley). The research was randomized, in 4 repetitions for both cultivars. Properties determined for French Marigold were: height, number of branches, number of leaves, and mass of fresh transplant, further more dynamic of growth have been monitored as well as development of flowers due to counting number of rosebuds, number of flowers and their diameter and in the end of research following parameters were measured: height, number of branches, diameter of stalk, mass of the above the ground part of the plant and mass of dry matter of the above of the ground part of plant. Regarding carrot following parameters were measured: diameter of the root, mass of the root, mass of the leaves, number and lenght of the leaves. The collected data have been statistically analyzed by variance analyzes (F test) and differences between treatments have been determined with LSD-test. Significantly higher values (P≤0.01) have been determined for French Marigold growth in substrate regarding those growth in soil and significantly higher values (P≤0.01) for carrots growth in Luvisol soil type.

The spring field pea is one of the most important coarse legumes. This study was carried out to investigate the response of a spring field pea variety to three plant densities (50, 100, and 150 plant m-2) during the 2017 and 2019 growing seasons in eastern Croatia. The field study was set up as a Randomized Complete Block Design (RCBD) in four replications. The results have demonstrated a significant effect of the plant densities and the growing seasons on the seed yield and on the following yield components: plant height and the number of pods/plant. The effect of plant densities on the number of seeds/pod and the thousand-seed weight was not significant. As for a growing season, the highest seed yield, plant height, the number of pods/plant were obtained in the second growing season. Furthermore, a maximum seed yield was recorded at the 150-plant m-2 plant density. This study has demonstrated that planting the spring field pea at different plant densities significantly modifies the spring field pea yield, plant height and number of pods/plant., Jari stočni grašak jedna je od najznačajnijih krupnozrnih mahunarki. Ovo je istraživanje provedeno kako bismo vidjeli reakciju utjecaja različitih gustoća sjetve na jari stočni grašak tijekom dvaju vegetacijskih ciklusa 2017. i 2019. godine u istočnome dijelu Republike Hrvatske. Pokus je postavljen po RCBD sustavu u četiri ponavljanja. Rezultati pokazuju značajan utjecaj gustoće sjetve i godina istraživanja na prinos zrna i većinu komponenata prinosa: visinu biljke i broja mahuna po biljci, osim broja zrna po mahuni i mase tisuću zrna, gdje gustoća sjetve nije statistički značajno utjecala na razlike u vrijednostima istraživanih svojstava. Najveće vrijednosti prinosa zrna, visine biljke i broja mahuna po biljci ostvarene su u drugoj godini istraživanja. Najveći prinos zrna zabilježen je pri gustoći sjetve od 150 biljaka/m2. Istraživanje pokazuje da različite gustoće sjetve značajno modificiraju/utječu na visinu prinosa zrna i komponente prinosa jaroga stočnog graška.

The aim of the study was to determine allelopathic potential of weed root exudates on germination and growth of crops. Field poppy (Papaver rhoeas L.), scentless mayweed (Tripleurospermum inodorum (L.) C.H. Schultz) and redroot pigweed (Amaranthus retroflexus L.) seedlings were grown in soil until 3-leaf stage. After their removal, the soil was re-sown with seeds of barley, soybean and oil pumpkin. The results of the experiment showed that field poppy and scentless mayweed root exudates stimulated root and shoot length, and fresh weight of barley seedlings up to 16.2%, 13.4% and 34.6%, respectively. Redroot pigweed root exudates showed no significant effect on emergence and growth of soybean and oil pumpkin.

The aim of the paper was to evaluate allelopathic effects of weed species Johnsongrass (Sorghum halepense) and black nightshade (Solanum nigrum) on germination and early growth of sugar beet. Petri dish experiment with water extracts prepared from different plant parts of weeds in 1, 5 and 10% concentrations and pot experiment with weed residues in rates of 10, 20 and 30 g/kg were conducted. Allelopathic potential was determined through germination, root and shoot length, and fresh and dry weight of sugar beet seedlings. Water extracts from various plant parts showed significant inhibitory potential, up to 100%, on germination and growth of sugar beet. Lower extract concentration promoted shoot length up to 35.5%. Johnsongrass residues showed negative effect on shoot length, fresh and dry weight of seedlings, especially in treatment with 30 g/kg residue rate. Contrary, black nightshade residues promoted sugar beet growth. Besides concentration/rate, allelopathic effect was dependent on extraction method, growth media and plant part.