Melliferous flora and pollen characterization of honey from Požega area

Melisopalinološkom analizom uzoraka meda s područja Požeške kotline utvrđen je peludni spektar koji ukazuje na botaničko podrijetlo meda. Najzastupljeniji je bio pelud vrsta iz porodica Asteraceae (6 svojti), Fabaceae (5 svojti), Rosaceae (4 svojte) i Fagaceae (3 svojte), dok je u najvećem broju uzoraka bio prisutan pelud svojti Brassica spp., Robinia pseudoacacia, Prunus spp. i Populus spp. Utvrđena su dva monoflorna repičina meda te po jedan kestenov i bagremov med, dok su ostali pripadali poliflornim vrstama meda. Tri poliflorna meda imala su značajan udio peluda svojti Brassica spp., a dva meda visok udjel peluda amorfe. Razdoblje cvatnje medonosnih biljaka ukazuje na to da su najznačajnije pčelinje paše Požeške kotline u travnju, svibnju i lipnju.Melissopalynological analysis of honey samples from Požega valley was used to determine the botanical origin of honey. The analysis showed the presence of 34 different pollen types, derived from plant taxa belonging to 18 families. The most represented plant families were Asteraceae (6 taxa), Fabaceae (5 taxa), Rosaceae (4 taxa) and Fagaceae (3 taxa), while the pollen types that appeared in most samples derived from Brassica spp., Robinia pseudoacacia, Prunus spp. and Populus spp. According to pollen spectra, two monofloral brassica honeys, as well as one chestnut and black locust honey, were determined, while other samples were considered as polyfloral. Three polyfloral honeys had a large portion of Brassica spp. pollen, while two had a high amount of Amorpha fruticosa pollen. Flowering period of melliferous plants in Požega valley suggests that the main foraging period for bees is during April, May and June

Rasprostranjenost pajasena (Ailanthus altissima (Mill.) Swingle), invazivne biljne vrste, na području grada Osijeka

The research on the tree of heaven (Ailanthus altissima (Mill.) Swingle) distribution within the Osijek city area was carried out in the summer period of 2017. In total of 589 individuals of the tree of heaven on 130 locations were recorded. The trees grew individually or in groups, mostly on abandoned places, and were rarely found in well-maintained areas. In the vicinity of the tree of heaven, mostly perennial herbaceous weeds were found. These plants thrive in different types of habitats. In order to prevent the uncontrolled spread of this invasive plant in the urban environment, it is necessary to continuously monitor and timely remove the tree of heaven individuals. Moreover, it is important to continuously educate the general public about the adverse impact of this species on the environment and biological diversity.Istraživanje prisutnosti pajasena (Ailanthus altissima (Mill.) Swingle) na području grada Osijeka provedeno je u ljetnom razdoblju 2017. godine. Na 130 lokaliteta zabilježeno je ukupno 589 jedinki stabala pajasena. Pajasen je rastao pojedinačno ili u skupinama, uglavnom na napuštenim područjima, dok je na uređenim i održavanim površinama bio rijetko prisutan. U neposrednoj blizini pajasena zabilježene su korovne, višegodišnje zeljaste biljke koje uspijevaju na različitim tipovima staništa. U svrhu sprječavanja nekontroliranog širenja ove invazivne biljke u gradskoj sredini potrebno je kontinuirano provoditi praćenje i pravovremeno uklanjanje pajasena, kao i kontinuiranu edukaciju šire javnosti o nepovoljnom utjecaju ove vrste na okoliš i biološku raznolikost

Comparative Study of Leaf Anatomy and Certain Biochemical Traits in Two Olive Cultivars

Olive (Olea europea L.) is one of the most cultivated trees in Dalmatia (Croatia). The aim of this work was to compare leaf anatomy, guaiacol peroxidases activity and soluble polyphenols content in two olive cultivars: Oblica and Leccino, to get preliminary data for further investigations of stress influence on their growth and productivity. Leaves from fi ve two–years–old trees of each, Olea europaea L. cv. Oblica and cv. Leccino were used in this study. Composed sample of each cultivar was used for determination of guaiacol peroxidases activity (GPOD), content of soluble polyphenols (PHEN) and dry weight (DW). The presence of lignin, suberin and callose were analyzed by histochemical reactions on fresh hand-made leaf sections. The leaf anatomy was studied on 3 μm thin sections stained with Toluidine blue O. There were significant differences of tissue areas between two olive cultivars. Bigger areas of upper and lower epidermis in cultivar Leccino leaves as well as bigger areas of schlerenchyma, idioblasts and intercellulars in leaves of cultivar Oblica were measured. Oblica had higher activity of GPOD and portion of DW than Leccino. Higher PHEN content was measured in Leccino leaves. Histochemical reactions showed more lignin and suberin in cultivar Oblica leaves. Based on the presented results, cultivars Oblica and Leccino should response differently on cold, salt and drought stress that should be the scope in further investigations

A fi nding of invasive alien beetle species Acanthoscelides pallidipennis (Motschulsky, 1874) in pods of indigo bush (Amorpha fruticosa L.)

Plodovi čivitnjače (Amorpha fruticosa L.), invazivne biljne vrste, prikupljani su tijekom 2017. godine na području Pokupskog bazena i u Županji. Na plodovima žljezdastim mahunama uočeni su izletni otvori te je utvrđena prisutnost invazivne vrste kukca Acanthoscelides pallidipennis (Motschulsky, 1873). Ova je vrsta autohtona na području Sjeverne Amerike, a njezina rasprostranjenost usko je vezana uz staništa čivitnjače i puteve širenja ove invazivne biljne vrste. Na području Pokupskog bazena u prikupljenim su uzorcima zabilježene ukupno 554 infestirane mahune, dok su u Županji bile infestirane 434 mahune te nije utvrđena statistički značajna razlika između dvaju istraživanih područja. Rezultati ukazuju na to da je kukac A. pallidipennis raširen u sastojinama čivitnjače na obama područjima te da je potrebno pratiti potencijal njegova širenja kako bi se spriječila infestacija i drugih biljnih vrsta, posebice onih iz porodice Fabaceae koje učestalo napada.A pods of indigo bush (Amorpha fruticosa L.), an invasive plant species were collected during 2017. in the area of the Pokupski basin and in Županja. In the laboratory there were observed exit holes on pods, which determined the presence of the invasive beetle species Acanthoscelides pallidipennis (Motschulsky, 1873). This species is native to the territory of North America, and its distribution is closely related to the habitats of the indigo bush. In the area of Pokupski basin within the collected samples there were found 554 infested pods, moreover in Županja there were 434 infested pods. Therefore, statistically significant difference was not found within two study sites. The results indicate that the A. pallidipennis is widespread in amorphous stands in both study sites and thus it is necessary to monitor the potential of its spreading in order to prevent infestation of other plant species, especially those from the Fabaceae family that are frequently infested

Comparative Study of Leaf Anatomy and Certain Biochemical Traits in Two Olive Cultivars

Olive (Olea europea L.) is one of the most cultivated trees in Dalmatia (Croatia). The aim of this work was to compare leaf anatomy, guaiacol peroxidases activity and soluble polyphenols content in two olive cultivars: Oblica and Leccino, to get preliminary data for further investigations of stress influence on their growth and productivity. Leaves from fi ve two–years–old trees of each, Olea europaea L. cv. Oblica and cv. Leccino were used in this study. Composed sample of each cultivar was used for determination of guaiacol peroxidases activity (GPOD), content of soluble polyphenols (PHEN) and dry weight (DW). The presence of lignin, suberin and callose were analyzed by histochemical reactions on fresh hand-made leaf sections. The leaf anatomy was studied on 3 μm thin sections stained with Toluidine blue O. There were significant differences of tissue areas between two olive cultivars. Bigger areas of upper and lower epidermis in cultivar Leccino leaves as well as bigger areas of schlerenchyma, idioblasts and intercellulars in leaves of cultivar Oblica were measured. Oblica had higher activity of GPOD and portion of DW than Leccino. Higher PHEN content was measured in Leccino leaves. Histochemical reactions showed more lignin and suberin in cultivar Oblica leaves. Based on the presented results, cultivars Oblica and Leccino should response differently on cold, salt and drought stress that should be the scope in further investigations

New data on distribution and habitats of medicinal fern taxa in Slavonia

Istraživanje ljekovitih svojti papratnjača provedeno je na tri lokaliteta na području Slavonije (istočna Hrvatska). Odabrani lokaliteti (Arboretum Lisičine, Park šuma Jankovac i grad Osijek) razvrstani su u dvije kategorije s obzirom na stupanj urbanizacije: 1) prirodna staništa/ruralna sredina i 2) urbana sredina. Zabilježeno je ukupno 12 svojti ljekovitih papratnjača unutar sedam porodica, od kojih su najzastupljenije svojte iz porodica Equisetaceae i Aspleniaceae. Samo jedna svojta bila je prisutna na svim lokalitetima. Ustanovljena je veća raznolikost svojti na prirodnim staništima. Zbog izraženih ljekovitih i nutritivnih svojstava kao i važnosti papratnjača u fitoremedijaciji, potrebno je provoditi daljnja istraživanja njihove raznolikosti u urbanim sredinama te educirati širu javnost o važnosti i mogućnostima primjene i uzgoja ove skupine biljaka u urbanim sredinama.Research on medicinal fern taxa was conducted at three localities in the area of Slavonia (eastern Croatia). The selected localities (Lisičine Arboretum, Jankovac Forest Park and the city of Osijek) are classified into two categories with regard to the degree of urbanization: 1) natural habitats/rural environment and 2) urban environment. A total of 12 taxa of medicinal ferns within seven families were recorded, of which the most represented taxa are from the families Equisetaceae and Aspleniaceae. Only one taxon was present in all localities. A greater diversity of taxa was found in natural habitats. Due to the pronounced medicinal and nutritional properties as well as the importance of ferns in phytoremediation, it is necessary to conduct further research into their diversity in urban environments and to educate the general public about the importance and possibilities of using and growing this group of plants in urban environments

Early spring flora of the Sub-Pannonic steppic grassland (NATURA 2000 site) in Bilje, northeast Croatia

The diversity of early spring vascular flora was studied in the Sub- pannonic steppic grassland in the village of Bilje, north eastern Croatia. In all, 109 plant taxa within 35 families were found. The highest number of taxa belongs to the families Poaceae, Fabaceae, Asteraceae, Caryophyllaceae, Lamiaceae and Rosaceae. Specific habitat conditions, characterized by moderately wet and moderately acidic soil with intermediate fertility and the effects of the continental climate favour the development of different plant life forms. Out of the total recorded plant taxa, hemicryptophytes make up 59.6%, followed by therophytes (22.0%) and geophytes (13.8%). Chorological analysis shows that the most numerous are plants of Eurasian (33.9%), Pontic-Central-Asian (21.1%) and Central European (21.1%) floral elements. According to their status in the Red List, three critically endangered (CR), one vulnerable (VU) and three nearly threatened (NT) plant species were found. Altogether, the steppe-like grassland in Bilje is a unique habitat rich in valuable plants of the Croatian flora, including the critically endangered Doronicum hungaricum, therefore it is of great importance to preserve it. Important management tools include mowing and controlling the spreading of cultivated and invasive plant species

Efficacy of learning about gymnosperms by individual work using textual and audiovisual teaching tools

Suvremeni pristup učenju i poučavanju kao i korištenje aktivnih metoda učenja stavljaju studente u središte nastavnog procesa. Odabir metoda poučavanja ovisi o ishodima učenja, ali i o studentovim sposobnostima učenja određenim metodama. Cilj ovog istraživanja bio je ispitati postižu li studenti bolje rezultate učenja kada uče individualnim oblikom rada pomoću tekstualnih nastavnih sredstava ili kada uče istim oblikom rada, ali primjenom audiovizualnih nastavnih sredstava (videozapisa). Individualni oblik rada uz pomoć dva nastavna sredstva primijenjen je u nastavi studenata 2. godine Preddiplomskog sveučilišnog studija Biologija. Istraživanje se sastojalo od 3 etape. U prvoj etapi studenti su pisali inicijalnu provjeru znanja, u drugoj su etapi nasumično podijeljeni u dvije eksperimentalne grupe za obradu nastavne teme Golosjemenjače, od kojih je jedna grupa obradila nastavnu temu pomoću tekstualnih materijala, a druga gledajući videozapis. U trećoj etapi pisali su završnu provjeru znanja kako bi se evaluirala uspješnost u savladavanju gradiva. Oba primijenjena nastavna sredstva rezultirala su povećanim prosječnim brojem ostvarenih bodova, a između postignutih rezultata nisu utvrđene statistički značajne razlike. Navedeno ukazuje da su oba nastavna sredstva podjednako učinkovita u usvajanju nastavnog gradiva te da ih je potrebno više implementirati u visokoškolsku nastavu.The modern approach to learning and teaching as well as the use of active learning methods put students at the center of the teaching process. The choice of teaching methods depends on the learning outcomes, but also on the student\u27s ability to learn using certain methods. The aim of this research was to examine whether students achieve better learning results when learning individually using textual teaching aids or when they learn in the same form of work, but using audiovisual teaching aids (videos). The research was conducted among students enrolled in the 2nd year of the Undergraduate Study Program in Biology. The research consisted of 3 stages. In the first stage, the students wrote an initial assessment test and in the second stage they were randomly divided into two experimental groups to study the part of the topic of the Gymnosperm, one of which studied using text materials, and the other by watching a video. In the third stage, they wrote a final knowledge test to evaluate their success in learning. Both teaching aids resulted in an increased average number of achieved points, i.e. grades, and no statistically significant differences were found between the achieved results. The above indicates that both methods are equally effective in the adoption of teaching material and that it is necessary to implement more of them in higher education teaching

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe