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Microsimulation traffic models are used to analyze and predict the functionality and safety of traffic networks, especially in critical areas such as intersections. These models have proven particularly useful in analyzing and comparing solutions in the early stages of design. In this paper, we compare the functional characteristics of an existing two-lane roundabout and a proposed replacement turbo roundabout. Our microsimulation modeling used the VISSIM traffic model, and we designed the conceptual turbo roundabout with AutoCAD and TORUS5 Roundabouts software., Mikrosimulacijski prometni modeli koriste se u analizi postojećih i predikciji budućih funkcionalnih i sigurnosnih karakteristika dijelova prometne mreže, osobito kritičnih dijelova poput raskrižja. Njihova primjena pokazala se osobito korisnom u analizi i ocjeni varijantnih rješenja u ranim projektnim fazama. U okviru ovoga rada pokazni su rezultati analize i usporedbe postojećeg dvotračnog kružnog raskrižja primarne funkcionalne razine i potencijalne rekonstrukcije u turbo kružno raskrižje. Za mikrosimulacijsko modeliranje korišten je mikrosimulacijski prometni model VISSIM, a idejno rješenje turbo raskrižja napravljeno je primjenom programa AutoCAD i TORUS 5 Roundabouts.

Dalmatian pyrethrum (Tanacetum cinerariifolium (TREVIR.) SCH.BIP.) is a plant species endemic to the east Adriatic coast. The bioactive substance of Dalmatian pyrethrum is a natural insecticide, pyrethrin, a mixture of six active components (pyrethrins I and II, cinerins I and II, and jasmolins I and II). The insecticidal potential of pyrethrin was recognized decades ago, and dried and ground flowers have traditionally been used in Croatian agriculture and households. A total of 25 Dalmatian pyrethrum populations from Croatia were studied to determine the pyrethrin content and composition, and to identify distinct chemotypes. The total pyrethrin content ranged from 0.36 to 1.30% (dry flower weight; DW) and the pyrethrin I/pyrethrin II ratio ranged from 0.64 to 3.33%. The statistical analyses revealed that the correlations between the percentage of pyrethrin I and of all the other components were significant and negative. The total pyrethrin content was positively correlated with the percentage of pyrethrin I and negatively correlated with cinerin II. The multivariate analysis of the chemical variability enabled the identification of five chemotypes among 25 Dalmatian pyrethrum populations. The chemical characterization of indigenous Dalmatian pyrethrum populations may serve as a good background for future breeding and agricultural exploitation.

Twenty-seven Ocimum basilicum cultivars were subjected to a chemical characterization of essential oil components by gas chromatography/mass spectrometry (GC/MS) and a genetic characterization using the amplified fragment-length polymorphism (AFLP) technique. Since the same 27 accessions had previously been classified into six morphotypes, these analyses allowed us to make detailed comparisons of chemistry, genetics, and morphology. The chemical composition and morphology of the studied cultivars appeared to have a strong genetic component. The AFLP analysis revealed a distinction between the green and purple morphotypes. The green morphotypes predominantly utilized the terpene biosynthetic pathway, while most purple morphotypes primarily utilized the phenylpropene biosynthetic pathway. The GC/MS analysis led to identification of 87 volatiles. Among the 27 cultivars, five chemotypes were identified. A detailed characterization of the essential oil constituents indicated the existence of both specific combinations of compounds and ‘private’ compounds with the potential to be used in many aspects of human life. The established relationship between a genetic profile, chemical composition, and morphology represents an important step in future breeding programs and in the cultivation of this species.

GC/MS was used to identify compounds of essential oils from seven Ocimum taxa (O. americanum L., O. basilicum L., O. campechianum Mill., O. x citriodorum Vis., O. kilimandscharicum Baker ex Gurke and three botanical varieties and cultivars of Ocimum basilicum L.: ‘Genovese’, var. difforme and var. purpurascens). Preliminary screening of their antibacterial activity was done against a number of common pathogens (Enterococcus faecalis, Enterococus faecium, Escherichia coli 0157:H7, Listeria monocytogenes, Listeria ivanovii, Proteus vulgaris, Staphylococcus aureus, Staphylococcus epidermis) using the filter paper disc agar diffusion technique, while further analyses were done by modification of the disc diffusion method. A broad variation in the antibacterial properties of investigated essential oils was observed. E. coli 0157:H7 was inhibited by O. basilicum ‘Genovese’ essential oil, while Ocimum americanum and Ocimum x citriodorum essential oils were the most effective against Enterococcus faecalis, Enterococcus faecium, P. vulgaris, S. aureus and S. epidermis.

The use of medicinal and aromatic plants (MAP) in Croatia has a very long tradition. Commercial gathering was economically important source of income in many Croatian regions. However, gathering in the wildness has a negative impact on biodiversity, collected plant material is not uniform and its price is significantly lower. Current production of medicinal and aromatic crops in Croatia is very limited. The MAP cultivation on family farms is usually marginal activity. MAP producers and processors generally agree that marketing opportunities do exist in case of a number of species. Natural MAP populations in Croatia show great biodiversity in morphological, biochemical and genetic level. The assessment of biodiversity is a starting point for efficient conservation of plant genetic resources and its use in plant breeding programmes. The main aim of the management of plant genetic resources is conservation, characterization, evaluation and documentation of the existing genetic biodiversity. For the purpose of conservation of these valuable genetic resources, The Collection of Medicinal and Aromatic Plants has been established at the Faculty of Agriculture, University of Zagreb, Croatia. Characterization and evaluation of accessions in plant genebanks is traditionally based on morphological traits. Currently, the analysis of target species including Dalmatian sage (Salvia officinalis L.), Dalmatian pyrethrum (Tanacetum cinerariifolium/Trevir./Sch. Bip.) and basils (Ocimum spp.) has been carried out on morphological, biochemical and genetic level.

Most commercial basil cultivars belong to the species Ocimum basilicum L. Moreover, within O. basilicum species there are six main botanical varieties and cultivars (var. basilicum 'Genovese', var. basilicum 'Sweet Basil', var. difforme Benth., var. purpurascens Benth., 'Dark Opal' and var. thyrsiflorum /L./ Benth.) which are mainly found on the market. High levels of both morphological and chemical variability exist within the species due to the intra- and interspecific hybridization and long-term uses throughout the world. The aim of this work was to study the resolving power of morphological traits for reliable identification of basil accessions. Phenotypic dissimilarities between pairs of accessions were calculated and the UPGMA dendrogram was constructed. Six clearly defined clusters have been detected, giving a good representation of traditional taxonomic relationships. To compare the efficiency of the morphological traits in accession identification, confusion probability and discriminating power of each trait was calculated. Our results show that with a careful analysis and stringent selection of traits, morphological markers provide an inexpensive and reliable method for routine screening of a large number of accessions, in order to monitor and manage germplasm collections.

DNA fingerprinting (AFLP) and chemical analyses of essential oils were utilized to define the extent of variation existing in the genus Ocimum. Research was carried out on 22 Ocimum accessions representing seven species. Concerning the essential oil composition of all investigated accessions, 115 compounds were identified. UPGMA cluster analysis, based on Euclidian distances of essential oil constituents between all pairs of accessions, showed four well-supported clusters (O. tenuiflorum, O. basilicum/O. africanum, O. basilicum, and O. americanum/O. africanum). Relating to the essential oil composition of all of the investigated accessions, 17 compounds were identified as the main ones, and according to them 13 chemotypes were determined. AFLP relationships were determined by neighbor-joining (NJ) cluster analysis based on Dice’s distance matrix and by maximum parsimony (MP) analysis. O. basilicum, O. americanum/O. africanum, O. tenuiflorum, and O. gratissimum represented four clusters supported with high bootstrap values. A neighbor-net diagram allowed the visualization of apparently conflicting data by revealing relationships between genotypes and chemotypes. Concerning the O. africanum species, two distinct chemotypes, geranial/neral (accession 11) and estragol (accession 10), have been established, while all the studied O. americanum accessions belong to the geranial/neral chemotype. This could be additional evidence that O. americanum is one of the parents of O. africanum. Furthermore, the fact that the O. africanum accession (10) as well as O. basilicum ‘Purpurascens’ and O. basilicum ‘Erevanskii’ accessions belong to the estragol chemotype supports the theory that O. africanum is one of the parents of these two O. basilicum accessions.

Species of the genus Ocimum, basil, are widely cultivated as a source of essential oil for use in foods, flavours and fragrances and as a culinary herb, spice and garden ornamental. Ocimum taxonomy is confused due to interspecific hybridization, polyploidization, and the existence of chemotypes or chemical races with similar morphology. Twenty-eight basil accessions, including six species O. basilicum L., O. americanum L., O. × citriodorum Vis., O. minimum L., O. gratissimum L., O. tenuiflorum L., and six botanical varieties or cultivars of O. basilicum var. basilicum 'Genovese', O. b. var. basilicum 'Sweet Basil', O. b. var. difforme, var. purpurascens 'Dark Opal' and O. b. var. thyrsiflorum, were analyzed by both random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) markers. Phylogenetic relationships were determined by neighbour joining cluster analysis based on dice distance between accessions. A very strong correlation between dice distance matrices based on RAPD and AFLP data were observed and the resulting neighbour-joining trees were congruent. High bootstrap support values for the branches separating O. tenuiflorum and O. gratissimum accessions, a cluster containing O. americanum and O. × citriodorum accessions, and a cluster containing O. basilicum and O. minimum accessions were observed in both cases giving a good representation of traditional taxonomic relationships. Within the O. basilicum cluster, similar accessions grouped together specifically O. minimum, O. basilicum 'Dark Opal' and O. basilicum var. difforme accessions. In addition to morphological, chemical and crossability data, RAPD and AFLP analyses can be a useful tool for resolving existing problems in identification and classification of basil.