Emina Mladenovic

Morphometric diversity in dwarf sour cherry germplasm in Serbia

Summary The search for growth-reducing rootstocks has produced selections of ‘Oblačinska’ sour cherry (Prunus cerasus L.) and European ground cherry (Prunus fruticosa Pall.). The methodological approach to germplasm collection was a compromise between a search for specific characters and random sampling of the population. On the principle of 19 variables in 27 accessions, this research brought valuable and diverse plant material into rootstock breeding. The vigour of adult trees on their own roots ranged from extremely weak, such as in selections of European ground cherry (SV1, SV3, SV4) and ‘Oblačinska’ sour cherry (OV31), to vigorous genotypes such as sour cherry (OV33 and OV34) and P. mahaleb. The natural habit of untrained trees varied from upright (e.g., SV7) to dropping (e.g., SV2). Internode lengths ranged from 1.36 cm (in SV8) to 4.11 cm (in SV4). Based on a PCA scatter-plot, six diverse sub-groups showing significant intra- and inter-species variability were distinguished. These findings were supported by high values of heritability, from 78.83 – 92.20%, implying the potential for successful selection of dwarfing genotypes based on their phenotypic characters in succeeding breeding activities. Preliminary field studies suggested that the ‘Oblačinska’ genotypes OV31 and OV32, as well as the European ground cherry genotypes SV1, SV2, and SV4, may represent rootstocks with the lowest vigour.

Opportunities and Benefits of Green Balconies and Terraces in Urban Conditions

Summary This study tested the hypothesis that a third dimension of urban gardening, in the form of green terraces and balconies, is of immense importance to the public well-being, mitigating climate changes and contributing to a more pleasant life in highly urbanized zones. By means of a concise questionnaire, a total of 82 respondents of different age groups (20-70 years of age) were surveyed about their opinion on green terraces, balconies, and roofs, i.e. the plants and flowers they incorporate. The fieldwork and survey responses facilitated the design of ten different spaces in various conditions. The results obtained enabled the selection of plants which could be used in given conditions, depending on wind, insolation, shade, ground levels, precipitation, etc. A total of three different terraces (out of ten) and three different balconies (out of ten) were enrolled in the study. The research results indicate that ten minutes of gardening could reduce stress levels and restore the positive energy of residents. An increase in the overall plant diversity exerts positive aesthetic and ecological effects. Inner-city areas are often sparsely vegetated, devoid of plants, and densely built-up, thus terraces and balconies have the potential to be retrofitted with suitable greenery.

Ecological Analysis of the Dendroflora of Futoški Park in the City of Novi Sad

Summary The purpose of this paper is to analyze the floristic composition, abundance, biological spectrum and ecological effects of Futoški Park trees and shrubs on the basis of bioindicators. The field research was conducted in Futoški Park, which is one of the oldest and largest parks in the City of Novi Sad, covering an area of 81,306 m2. Upon determining the floristic composition of Futoški Park and the protection zone around the Park hotel, a total of 121 genotypes were recorded, out of which 34 species and lower taxa belong to the Gymnosperm phylum (Pinophyta) and 87 species and lower taxa belong to the Angiosperm phylum (Magnoliophyta). A total of 5,228 representatives of dendroflora were found. The biological range of trees and shrubs in the study area mostly includes deciduous nanophanerophytes (34.98%) and evergreen nanophanerophytes (33.72%), whereas the remainder includes evergreen phanerophytes (16.35%) and the least prevalent deciduous phanerophytes (14.94%). The analysis of ecological indices shows that the greatest number of species meet the environmental requirements, and are successfully acclimated to the climatic and soil conditions. On the basis of the overall vitality and ornamental features of the dendroflora analyzed, it can be argued that Futoški Park is a unique ecological and environmental entity in the urban structure of the city.

Germination and Relations between Seed Quality Characteristics for Acer pseudoplatanus and Acer pseudoplatanus ‘Atropurpureum’

Summary The purpose of this paper is to analyze relations between seed quality characteristics and the influence of contaminated urban areas on seed quality of sycamore maple trees in different locations across Novi Sad (Serbia). This research analyzed seed germination of 29 adult trees of sycamore maple (Acer pseudoplatanus L.) and its red leaf variety (Acer pseudoplatanus ‘atropurpureum’ Späth.). Our results indicate a medium strong positive correlation between seed weight and viable seed. Sycamore maple trees from the same urban typology do not have significant influence on seed quality characteristics, while different urban typology has such influence. These results explain the negative influence of urban areas on seed quality characteristics. For selection of high value trees in urbanized and contaminated areas, seed quality can be the indicator of adaptability to stress related conditions.

Inheritance of floral colour and type in four new inbred lines of ornamental sunflower (Helianthus annuus L.)

ABSTRACT Sunflower (Helianthus annuus L.) is grown commercially and as an ornamental plant. Floral colour and inflorescence type are important traits in the breeding of ornamental sunflower. Sunflowers consist of ray florets, which are arranged around the perimeter with disc florets in the centre. The colour of the ray florets can vary from various shades of red to lemon-yellow. The inheritance of ray floret colour was studied through diallel crossing of inbred lines with red, yellow, or lemon-yellow coloured florets. In the F1 generations, the red colour was partially dominant over yellow and lemon-yellow ray florets, forming a ‘Gaillardia‘ pattern, while yellow was dominant over lemon-yellow. The segregation ratios in the F2 generations were 9:7 (red × yellow) and 3:1 (red × lemon-yellow and yellow × lemon-yellow), indicating control by one or two genes, respectively. The colour of the disc florets depended on the presence or absence of anthocyanin pigmentation. Disc florets that lacked anthocyanin pigmentation were usually different shades of yellow. Anthocyanin pigmentation was dominant over yellow and lemon-yellow, showing monohybrid inheritance with a segregation ratio of 3:1 in the F2 generation. Chrysanthemum-type inflorescences had elongated disc florets. In crosses between chrysanthemum-type and normal-type inflorescences, the segregation ratio in the F2 populations corresponded to the theoretical ratio of 3:1 for chrysanthemum-type:normal-type inflorescences. We conclude that the genes controlling floral colour and inflorescence type are inherited independently and have different effects. The interaction of these genes revealed new combinations of floral colour and type, which can increase variability in ornamental sunflowers.

Effect of Plant Growth Regulators on the Propagation of African Violet (Saintpaulia ionantha H. Wendl.) from Leaf Cuttings

Summary The purpose of this paper is to examine the effects of commercial plant growth regulators (PGRs), namely Inict-1 and Incit-5, on the rooting of African violet leaf cuttings (Saintpaulia ionantha H. Wendl.). The production of African violets has grown considerably in recent years, thus it is important to study the most rapid and cost-effective means of mass production. The propagated plant material of the cultivar ‘Nagano’ was treated with Incit-1 and Incit-5. The following parameters were observed: the occurrence of the first root, the number of formed secondary roots and root lengths, the occurrence of the first leaf, and the occurrence of the first flower. The results obtained showed that the use of commercial rooting hormones, namely Incit-1 and Incit-5, exerted positive effects on the duration of rooting, the number of secondary roots formed, and the root lengths of African violets. During the research, it was observed that the rooting durations of all the plants treated with Incit-1 and Incit-5 were 5 days shorter. The results indicate that the plants treated with PGRs necessitate less time to root, less time to produce new leaves, and, consequently, less time to produce flowers.

Evaluation of Sunflower Genotypes for Ornamental Use

Summary Sunflower (Helianthus annuus L.) is a species with interspecies variability, especially in qualitative traits. From horticultural point of view it is important to choose genotypes with desired characteristics. Knowing of genotypes characteristics is essential to choose the correct genotypes that can be used in gardens and like cut flowers. Present research was carried out at Institute of Field and Crops at Rimski Šančevi in Novi Sad, Serbia. Experiment included four genotypes of ornamental sunflower. Significant variation for morphological traits were observed. Qualitative characteristics such as flower color, also showed great variability. Base on the results all genotypes can be recommended as garden plants and cut flowers.