The increasing fragmentation and degradation of forest habitats and the hybridization with cultivated varieties potentially threaten the genetic integrity of wild apple (Malus sylvestris /L./ Mill) and wild pear (Pyrus communis L.). Wild apple and wild pear have been included in the European Forest Genetic Resources Programme – EUFORGEN priority lists for development of conservation strategies. Researches are required into the genetic diversity and the structure of local populations to determine the most suitable conservation policies for these species at different scales. In this study, the RAPD markers were used in order to evaluate interspecies genetic similarity of wild apple trees and wild pear trees from the Starcevica Forest Park, Banja Luka, Bosnia and Herzegovina. Primers OPA-05, OPA-07, OPA-09, OPA- 10, OPG-03, OPG-11, OPG-12, OPG-13 and OPAC-03 were used to analyse genetic similarity of wild apple trees, while OPA-01, OPA-03, OPA-05, OPA-07, OPA-08, OPD-04, OPD-14, OPG-03 and OPG-06 were used to analyse genetic similarity of wild pear trees. There was a high level of polymorphism among the analysed wild apple trees, as well as among the wild pear trees, demonstrating a considerable richness in terms of wild apple and wild pear genetic resources in the Starcevica Forest Park. The significant genetic diversity of wild apples and wild pears is present between different test polygones, while when it comes to diversity within the test polygons, it can be concluded that very similar genotypes of wild apples and wild pears generally prevail within a polygon.

In July 2015, 179 grapevine plants belonging to 16 grapevine autochthonous cultivars were assessed for sanitary status using DAS ELISA test for the presence of: Grapevine fanleaf virus (GFLV), Grapevine leafroll-associated virus 1 (GLRaV-1), Grapevine leafroll-associated virus 2 (GLRaV-2)and Grapevine leafroll-associated virus 3 (GLRaV-3). Furthermore, surveyfor the phytoplasma presence and laboratory analyses using nested-PCR/RFLP assay was conducted at the beginning of September 2015 on grapevine cultivars which were not positive in DAS ELISA test for the presence of the four viruses. Out of 179 tested plants with DAS ELISA test, 146 (81%) were positive for the presence of at least one virus. The most widespread viruses were GFLaV- 1 and GFLaV- 3 with approximately 80 % of grapevines infected. Nested–PCR/RFLP assay showed that out of 33 tested samples 2 were positive for the presence of phytoplasmas from 16SrXII group. Sanitation of infected grapevine cultivars is needed in near future.

Molecular confirmation of the process of differentiation of meristematic tissue of plants is primarily based on histomorphological characterization of the tissues carrying these processes. For perennial plants – fruit trees, the knowledge of these processes is important to define runtime type and pomotechnical treatments but also to identify the genes responsible for determination of the apices into a generative phase of differentiation. Which apex extraction techniques will be applied depends on the structure of buds, i.e. whether an apex differentiates only into generative elements – pure flower buds, or the differentiation goes into two directions: differentiation of leaf primordium with axillar meristematic dome and differentiation of generative elements of flowers in the peak or lateral zone of an apex – mixed buds. The fruit trees of the genus Prunus have purely flower buds and for this purpose the whole apex is taken, between protection – cover leaves, on lateral positions of all collateral buds at shoot nodes. The moment of initiation of determination and the dynamics of differentiation of generative buds are different at different type of shoots on a tree. It is therefore necessary to know the shoots growth cessation time which is in correlation with apex determination. Fruit trees of the genus Prunus are ending the growth of shoots by rejection of shoot peaks, and the cast away time depends on the type, length and the position of shoots.

Intensive high-density plantings (HDP) of plum trees in the Republika Srpska involve the use of Myrobalan (Prunus cerasifera Ehrh.) seedling as the predominant and, in most cases, the only rootstock. Using Myrobalan as a vigorous rootstock is a serious challenge in growing plums at higher planting densities. Although Myrobalan seedling rootstock increases the vigour of grafted cultivars, plum trees trained to the spindle system on Myrobalan rootstock can also be grown at very high plant densities ranging from 1,000 to 1,800 trees per hectare, depending on the cultivar/rootstock combination and central-leader inclination. The most common training system for plums in high density plantings is the slender spindle or the spindle bush system. Successful training and maintenance of spindle systems in intensive production on high-vigour rootstocks is not possible without the consistent use of canopy management practices, particularly during the first three years after planting, when these practices are most intensive for proper training of both the central leader and main lateral branches. Canopy management practices require a professional attitude and substantial manual labour. Particular importance in training spindle systems for plums as well as in maintaining the training system (replacement of spur-bearing branches) is given to the following specific canopy management practices: notching, shoot bending, shoot twisting, undercutting and replacement of spur-bearing branches. This paper outlines some important canopy management practices and their effect on plum growth and development, focusing on cultivar-specific responses to treatments.

In Montenegro more than 200 000 fig trees are registered with an annual production of about 4000 t. A survey was conducted on fig trees of different varieties, located in a commercial orchard in Podgorica and a germplasm collection located in Bar, Montenegro, to assess the presence of five fig viruses i.e. Fig mosaic virus (FMV), Fig leaf mottle-associated virus 1 and 2 (FLMaV-1 and -2), Fig latent virus 1 (FLV-1) and Fig mild mottle-associated virus (FMMaV). In May 2015, leaf samples were taken from 21 fig trees showing leaf discolorations, vein clearing, ring spots, leaf distortion and mosaic symptoms. Total RNA was extracted using RNeasy Plant Mini Kit (QIAGEN) and tested by RT-PCR using virus-specific primers (Elbeaino et al., 2006, 2009, 2010). RT-PCR results showed infections with FMV (9 of 21 samples tested), FLMaV-1 (18 of 21) and FMMaV (2 of 21), whereas FLMaV-2 and FLV-1 were not detected. FMMaV was identified only in samples from Bar in mixed infection with FMV and FLMaV-1. Nucleotides sequence analyses of PCR amplicons obtained (GenBank accession Nos. KU198374-KU198377, KU198383-KU198389) revealed that at the nucleotide level, FMV, FLMaV-1 and FMMaV isolates from Montenegro shared 86-95%, 93-95% and 84- 95% identity, respectively with homologues in the GenBank. To our knowledge, this is the first report of FMV, FLMaV-1 and FMMaV in fig trees in Montenegro. In the future, an extensive survey on more samples could allow a better evaluation of the sanitary status of this crop in the country.

This study presents results of the analysis of the differentiation degree of flower buds at different stages of growth of the long shoots in apricot. Long shoots are oneyear-old shoots where terminal growth is stopped and continued several times during the vegetation (I-IV). In that way the flower buds are formed at different periods. Histological analysis of the flower buds on different growth flushes shows differences in the degree of differentiation as a consequence of bud positioning on those flushes of growth. Hence, the buds on the first growth flush are the most differentiated, while less degree of differentiation is observed on the buds on the last growth flushes (III and IV). Different degree of differentiation of the buds influences their growth and development in the early spring which represents an important factor regarding adaptation to the given growing conditions and finally affect yielding potential. Namely, buds from the first growth flush are the first to develop in spring and give the least contribution to the yielding potential (13.06-21.35%). Buds from the II and III growth flush, which have the lower degree of differentiation and are developed later compared to the buds of the I growth flush give a larger contribution to the yielding potential (38.02-41.71%). In this paper the degree of differentiation of the flower buds is analysed and realization of the yielding potential of the different flushes of growth on the long shoots in cultivars ‘Hungarian Best’ and ‘Novosadska Rodna’ in the years 2011 and 2012. The influence of the degree of differentiation of the flower buds on their productivity in relation of the position on the different growth flushes can successfully serve as one of the elements for modelling growth and fruit bearing in apricot on the long shoots.

During May 2015, a small scale survey was conducted on 27 fig trees situated in three locations (Mostar, Trebinje and Ljubuski) in Bosnia and Herzegovina, to investigate the presence of Fig mosaic virus (FMV), Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV- 2) and Fig mild mottle-associated virus (FMMaV). Samples consisted of leaves singularly taken from trees with symptoms of mosaic, vein yellowing, ring spots, necroses and leaf malformations (23 plants) and one asymptomatic tree, all situated in a fig germplasm collection plot. Additional three samples were taken from symptomatic fig plants of three outdoor gardens. Total RNAs extracted from the leaf midrib using RNeasy Plant Mini Kit (QIAGEN), were used in RT-PCR assays with specific primer pairs for each virus following protocols described in Elbeaino et al. (2006, 2009, 2010). RT-PCR results revealed 19 FMV- (70%), 25 FLMaV-1- (92%) and 4 FMMaV- (15%) positive samples. Double infections with FLMaV-1 and FMV were detected in 74% samples, while triple infections with FLMaV- 1, FMV and FMMaV affected 15% of tested figs. After cloning and bi-directional sequencing of 2 clones from random PCR amplicons for each virus, nucleotide BLASTn sequence analyses for FLMaV- 1 (350 bp) (GenBank Accession Nos. KU198378-KU198382), FMMaV (311 bp) (KU198388) and FMV (302 bp) (KU198367-KU198373) showed identity levels of 84-95%, 89-92% and 83-97%, respectively, with homologues available in GenBank. To our knowledge, this is the first report of three fig-infecting viruses (FLMaV-1, FMMaV and FMV) in Bosnia and Herzegovina and the results obtained, even if limited, reflect a precarious sanitary status of fig that needs a clean stock program in this country.

The research on 10 old and indigenous pear cultivars was conducted during 2012 and 2013 in Bosnia and Herzegovina. The following characteristics were determined: fruit weight, fruit length and width, stalk length and width, fruit flesh firmness ; soluble solids content and total dry matter content of the fruit juice ; pH, titratable acidity, vitamin C, total phenolics, total flavonoids and antioxidant activity of the fruit cell juice. On the basis of the Principal Component Analysis (PCA) of pomological fruit characteristics the studied cultivars were divided into four main groups. Based on the PCA of biochemical traits the studied cultivars can be divided into three groups. Extremely high phenolic content in the cvs Mioljnjaca, Žutica, Poljakinja, Karamut and Gradiscanka recommends them for their inclusion in a breeding programme. The cvs Mioljnjaca and Poljakinja are also characterised by large and firm fruit and since the antioxidant capacity affects the duration of fruit storage, it is expected that these traditionally grown varieties can survive longer and keep their valuable nutritional ingredients longer.

Detection of viruses presence were carried out for the 225 a of pome and stone fruit trees from the collection of the Genetic Resources Institute of University of Banja Luka, located within the Botanical Garden of the University, tested by DAS-ELISA. The pome fruit trees were analyzed on presence of the following viruses: Apple Chlorotic Leaf Spot Virus (ACLSV), Apple Stem Grooving Virus (ASGV), Apple Stem Pitting Virus (ASPV) and Apple Mosaic Virus (ApMV). The stone fruits were analyzed on presence of Plum Pox Virus (PPV), Prune Dwarf Virus (PDV) and Prunus Necrotic Ring Spot Virus (PNRSV). All samples were tested serologically by DAS-ELISA. In addition to this, virus negative pear and apple accessions were tested for 'Candidatus Phytoplasma mali' and 'Candidatus Phytoplasma pyri' presence using nested-PCR/RFLP analyses.

The yield potential of ten plum cultivars (‘Cacak's Beauty’, ‘Cacak's Best’, ‘Cacak's Fruitful’, ‘California Blue’, ‘Elena’, ‘Hanita’, ‘Katinka’, ‘Renclode Althan’, ‘Stanley’, and ‘Top’), exhibited through the structure of buds on long bearing shoots, was analyzed under the agro-ecological growing conditions of the Banja Luka region for two fruiting seasons (2012 and 2013). Long bearing shoots with collateral buds were the most productive type of fruiting branches, which is why the structure of buds on these branches is the basis for defining specific cultural measures in order to boost yield potential. Based on the established structure of buds on the nodes along the long bearing shoots and the established yield potential, the plum cultivars evaluated were classified into 4 groups: 1) cultivars with a predisposition to have a high yield potential, without need for specific treatments in fruiting control (‘Cacak's Beauty’ and ‘Top’); 2) cultivars with a predisposition to have a high yield potential with the application of cultivar-specific cultural measures for control of fruiting (‘Cacak's Best’, ‘Elena’, and ‘Stanley’); 3) cultivars that require differentiated cultural measures in the control of yield potential for regular fruiting (‘Cacak's Fruitful’, ‘California Blue’, and ‘Katinka’) and 4) cultivars that require innovative growing systems and specific cultural treatments to control fruiting (‘Hanita’ and ‘Renclode Althan’).

In this study, genetic diversity of 119 accessions of common bean (Phaseolus vulgaris) from five former Yugoslav republics constituting the western Balkans was assessed by 13 microsatellite markers. This set of markers has proven before to efficiently distinguish between bean genotypes and assign them to either the Andean or the Mesoamerican gene pool of origin. In this study, 118 alleles were detected or 9.1 per locus on average. Four groups (i.e., Slovene, Croatian, Bosnian, and Serbian) showed similarly high levels of genetic diversity as estimated by the number of different alleles, number of effective alleles, Shannon’s information index, and expected heterozygosity. Mildly narrower genetic diversity was identified within a group of Macedonian accessions; however, this germplasm yielded the highest number of private alleles. All five germplasms share a great portion of genetic diversity as indicated by the analysis of molecular variance (AMOVA). On the basis of the scored number of migrants, we concluded that the most intensive gene flow in the region exists in Bosnia and Herzegovina. Cluster analysis based on collected molecular data classified the accessions into two large clusters that corresponded to two gene pools of origin (i.e., Andean and Mesoamerican). We found that Andean genotypes are more prevalent than Mesoamerican in all studied countries, except Macedonia, where the two gene pools are represented evenly. This could indicate that common bean was introduced into the western Balkans mainly from the Mediterranean Basin. Bayesian cluster analysis revealed that in the area studied an additional variation exists which is related to the Andean gene pool. Different scenarios of the origin of this variation are discussed in the article. Common bean (2n = 2x = 22) is the most important edible food legume for direct human consumption in Europe and in the world as it represents a valuable source of proteins, vitamins, fiber, and minerals (Broughton et al., 2003). The Andean region and Mesoamerica are distinguished as the two major centers of origin of this species, according to morphological characters (Singh et al., 1991), seed proteins (Gepts et al., 1986), isozymes (Koenig and Gepts, 1989), DNA markers (Freyre et al., 1996), and sequence data (Schmutz et al., Received for publication 10 Feb. 2015. Accepted for publication 14 Apr. 2015. This work was financially supported by FP7 Project CropSustaIn, grant agreement FP7-REGPOT-CT2012-316205, by grant No. 168/01 from the SEE-ERA.NET.PLUS FP7 Regional Programme and by grant P4-0072 from the Slovenian Research Agency. Accessions in Republic of Srpska, were collected through the National Program for Plant Genetic Resources, with a financial support by Ministry of Science and Technology of the Republic of Srpska.We are thankful toMatej Knapi c fromAgricultural Institute of Slovenia for preparing a geographic map of the western Balkans with collection sites of the studied common bean accessions. Corresponding author. E-mail: marko.maras@kis.si. 308 J. AMER. SOC. HORT. SCI. 140(4):308–316. 2015. 2014). After its domestication in the Americas, common bean promptly spread worldwide (Zeven, 1997). Introduction of this species in Europe dates to the early 16th century when Spanish and Portuguese sailors brought bean specimens to their homelands from both centers of domestication (Gepts and Bliss, 1988). During the last five centuries of cultivation, many landraces and cultivars evolved under diverse environments and farmer preferences in Europe (Zeven, 1997). Though many local cultivars were lost in the last 60 years, there are still many farmers who maintain old local landraces, which are well adapted to the pedoclimatic conditions peculiar to their limited geographical areas, and who have been exchanging their seeds with surrounding areas, mainly in local markets. The pathways of dissemination of the common bean into and across Europe were very complex, with several introductions from America, combined with direct exchanges between European and otherMediterranean countries (Papa et al., 2006). In the past two decades, phaseolin seed protein and other genetic markers have been intensively used to analyze the structure of European common bean populations and distribution of the two gene pools. A prevalence of the Andean ‘‘C’’ and ‘‘T’’ phaseolin types (76%) was first detected by Gepts and Bliss (1988), and was then confirmed by Lioi (1989) in an analysis of a large collection from Italy, Greece, and Cyprus (66% in total), by Logozzo et al. (2007) for a broad European collection (76%), and by others for Portuguese and Spanish genotypes (Rodino et al., 2001, 2003). Similar distribution of Andean and Mesoamerican genotypes has also been observed in phaseolin and molecular marker analyses at a regional scale (Angioi et al., 2009; Limongelli et al., 1996; Piergiovanni et al., 2000; Sicard et al., 2005; Su star-Vozli c et al., 2006). Moreover, several studies have focused on hybridization between the Andean and Mesoamerican gene pools in Europe. This phenomenon was first evidenced in the Iberian Peninsula by analyzing phaseolins, allozymes, and morphological characters (Rodino et al., 2006; Santalla et al., 2002), and later by inter-simple sequence repeat and simple sequence repeat (SSR) markers from both the chloroplast and nuclear genomes of European genotypes (Angioi et al., 2009, 2010; Sicard et al., 2005). Information on genetic diversity of common bean in the western Balkans that encompasses former Yugoslav republics (i.e., Slovenia, Croatia, Bosnia and Herzegovina, Macedonia, and Serbia) is scarce. In this region, common bean represented a very important food in the human diet for centuries. Until World War II, this crop was grown on large areas (>1 million ha) in the field often together with maize (Zea mays). In the second half of the last century new cultivars of both maize and common bean were introduced into crop production, and the old cropping system was abandoned, which subsequently, lead to a great reduction of the areas covered by beans ( 120,000 ha). Different approaches for assessing diversity at the molecular level are presently available. Microsatellites have been considered as the reference markers for cultivar fingerprinting in common bean because they are codominant, widely distributed in the genome, highly polymorphic, and highly repeatable (Powell et al., 1996; Yu et al., 1999). In this study, the genetic diversity of common bean from the western Balkans was assessed by SSR markers. A total of 13 markers that proved in previous studies (Maras et al., 2006, 2013) to be highly polymorphic and as efficient as amplified fragment length polymorphism markers in distinguishing common bean genotypes according to their gene pool of origin (Maras et al., 2008)were employed. The collectedmolecular data allowed us to: 1) examine the relationships among the accessions and the organization of common bean genetic variation in the western Balkans, 2) identify the original gene pool (Andean or Mesoamerican) of the studied plant material, and 3) clarify the bean dissemination process in the western Balkans. Materials and Methods PLANT MATERIAL. A total of 119 common bean landraces from national gene banks of five former Yugoslav republics were used in this study (Table 1; Fig. 1). These included 25 accessions from Bosnia and Herzegovina, 18 from Croatia, 28 from Macedonia [former Yugoslav Republic of Macedonia (FYROM)], 30 from Serbia, and 18 from Slovenia (passport data of the accessions are available upon request). Out of 18 Slovene accessions included, 14 of them have already been assessed for genetic diversity and phaseolin type in our previous studies (Maras et al., 2013; Su star-Vozli c et al., 2006) and were used here as a reference material for the determination of gene pool of origin of the other 105 accessions. DNA EXTRACTION. Total DNA was extracted from bulked leaf material of 10 plants of each accession using BioSprint15 DNA Plant Kit (Qiagen, Germantown, MD) and MagMax Express Magnetic Particle Processor (Life Technologies, Grand Island, NY) following manufacturer’s instructions. Integrity and quality of DNA were evaluated by electrophoresis on 1.0% agarose gels. Concentrations of DNA samples were determined with a fluorometer (DyNA Quant 200; Hoefer, Holliston, MA). MOLECULAR ANALYSES. Thirteen SSR loci developed by Metais et al. (2002) andGaitan-Solis et al. (2002)were employed (Table 2). Amplification reactions were performed with a Veriti Thermal Cycler (Life Technologies) in 10-mL reaction mixtures. Each reaction contained 1 · polymerase chain reaction (PCR) buffer, 2 mM MgCl2, 200 mM nucleoside triphosphates, 0.25 mM unlabeled right primer, 0.25 mM labeled left primer, 0.5 U of Taq DNA Polymerase (Biotools, Madrid, Spain), and 20 ng of genomic DNA. Loci were amplified using a profile of initial denaturation at 95 C for 3 min, followed by 30 cycles of strand denaturation at 94 C for 30 s, primer annealing at 47 to 62 C for 30 s, DNA extension at 72 C for 30 s, and final extension at 72 C for 4min. Fluorescently labeled PCR products were mixed with formamide and internal size standard GeneScan350 ROX (Life Technologies) and genotyped on the 3130xl Genetic Analyzer (Life Technologies). DATA ANALYSES. For each SSR marker, alleles of different sizes were scored. Basic statistics, including observed number of alleles, expected heterozygosity, polymorphic information content (PIC), and probability of identity (PI) were calculated in Identity 1.0 (Wagner and Sefc, 1999) and MicrosatelliteToolkit (Park, 2001). The number of total, effective, and private alleles and alleles with frequency over 5% were calculated for each of the five groups of accessions using GenAlEx 6.1 (Peakall and Smouse, 2006). The same software was used for the estimation of Shannon’s information index and expected heterozygosity of overall loci in single groups of accessions. A

The Botanical Garden of the University of Banjaluka is part of the “University City” complex sprawling over 5.3 ha. The complex began as the "Vrbas" Austro-Hungarian barracks at the end of the nineteenth century and it was used for military purposes until 2004. After being assigned to the University of Banja Luka in 2004, the area was allocated to the Genetic Resources Institute to make use of it. The Botanical Garden facilities are divided into three separate sections. In one section, the setting up of the botanical collections of genetic resources has begun. There is a fruit collection and preliminary characterization has also started on the accessions. In addition, ex-situ collections of vegetables, aromatic and medicinal plants and herbs, industrial and wild plants were designed. In the middle section, a pond was planned and the establishment of an arboretum collection was initiated, with representatives of autochthonous woody species. In the third section, green houses were designed and a building with gene bank facilities and laboratories was built. The Botanical Garden of the University of Banja Luka, as a place for ex-situ plant conservation, is of great importance for the conservation of biodiversity as well as for scientific research in this field.