Dragan Nikolic

This study evaluated 24 strawberry genotypes, including 12 parental varieties and 12 progenies, using chemical and sensory analyses to assess fruit quality and panelist preferences. Sugar and organic acid profiles, total -soluble solids, titratable acidity, phenolic content, radical-scavenging activity, and sweetness index were determined. Statistical analyses examined correlations among quality parameters, focusing on the influence of sugars and acids on the Brix/TA ratio. Sensory evaluation confirmed panelists’ perception of sweetness and sourness differences. Progeny cultivars BL34 Sandra, BL29 Nadja, and BL42 Federica showed superior quality; two were registered as new varieties, while one is under registration.

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The phenotypic variability of 50 European plum ( Prunus domestica L.) cultivars from the germplasm collection of the Faculty of Agriculture in Belgrade was evaluated on the basis of 7 qualitative and 24 quantitative traits over three years. A great diversity between cultivars was found for all analysed traits. The results show that qualitative traits play an important role in the identification of cultivars, as each cultivar has a unique combination of scores. Among the quantitative traits, the greatest variation was found in yield efficiency (0.027–0.757 kg cm ⁻² ; CV = 67.0%), yield (4.4–35.7 kg tree ⁻¹ ; CV = 45.6%), maturity index (9.4–42.9; CV = 36.1%), titratable acidity (5.2–17.2 g l ⁻¹ ; CV = 29.4%) and fruit weight (16.5–73.7 g; CV = 29.6%). Principal component analysis (PCA) revealed that the traits related to ripening time, fruit weight, quality and yield accounted for most of the observed variability. Cluster analysis (CA) grouped the analysed cultivars into two main clusters with several subclusters. The results of the present work provide important information on how to best utilise these plum cultivars and can help breeders to select the most diverse cultivars with the best fruit and yield characteristics to be crossed in future breeding programmes.

The aim of this study was to examine the dimensions and surface morphology of pollen grains of some sweet and sour cherry genotypes through scanning electron microscopy (SEM) as an additional alternative identification tool. In vitro pollen germination and pollen tube length as indicators of their viability were determined as well. Observations were carried on 10 sweet cherry (Prunus avium L.) and 7 sour cherry (Prunus cerasus L.) genotypes. All genotypes had prolate, tricolpate pollen grains, and striate exine ornamentation, with more parallel longitudinal ridges. Significant differences among genotypes within species and between species were found for most pollen grain characteristics and exine ornamentation. In both sweet and sour cherry the largest variability was recorded for colpus length (CV = 15.0% and 12.9%, respectively). For sweet cherry genotypes, in vitro pollen germination and pollen tube length ranged between 1.4% to 51.5% and 360.4 to 669.3 μm respectively, while for sour cherries they ranged from 15.5% to 37.0% and 96.3 to 960.2 μm, respectively. The results of the correlation analysis showed that in vitro pollen germination correlated positively with pollen length/pollen width (L/W) ratio (r = .640) and furrow width (r = .588), and negatively with the number of ridges (r = −.517), while pollen tube length was not significantly correlated with any of the studied characteristics. Principal component analysis (PCA) revealed that pollen length, pollen width, L/W ratio, colpus length, mesocolpium width, and ridge width are relevant tools to discriminate among the studied genotypes. The measurements made on pollen grains did not reveal individually big differences, but when all features were considered together, the pollen of each genotype exhibited a unique pattern. The distribution on the scatter plot showed considerable variation among sweet and sour cherry genotypes based on pollen morphological characteristics, which led to their distribution into two separate groups. This demonstrates the ability to distinguish cherry species based on pollen morphological characteristics determined by SEM. To improve discriminative ability for genotypes within species combination between pollen ultrastructural analysis, morphological and molecular markers is desirable, in subsequent work.Research Highlights: Significant differences in pollen characteristics between sweet and sour cherry. Significance of pollen morphology in taxonomic differentiation. Significance of SEM studies for the taxonomic identification.

The flowering and fruit set of grapevines are determined by many morphological, physiological, and environmental factors. Although the elemental composition of pollen grains plays a crucial role in the fruit set, there is still a considerable gap in our knowledge. To date, no study has been conducted on the elemental composition of Vitis vinifera subsp. sylvestris (hereafter V. sylvestris) pollen grains. The aim of this work was to investigate the elemental composition of pollen grains of V. sylvestris using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The pollen grains of ten V. sylvestris individuals (eight male and two female) and one hermaphrodite cultivar ‘Plavac mali crni’ were analyzed. SEM-EDX analysis revealed the presence of eight elements (carbon—C, oxygen—O, magnesium—Mg, phosphorus—P, potassium—K, calcium—Ca, molybdenum—Mo, and aluminum—Al) in the pollen grains. Interestingly, aluminum was detected exclusively in the pollen of the cultivated grape cultivar ‘Plavac mali crni’, while it was not present in the genotypes of V. sylvestris. No significant differences between genotypes were found for oxygen and phosphorus, while significant differences were found for other elements. Pollen dimorphism was not associated with differences in element composition, although principal component analysis separated the genotypes into two distinct groups, with two female individuals (Pak10 and Pak12) and one male (Im19) tending to form separate clusters. This study is the first report on the elemental composition of pollen grains of V. sylvestris genotypes and provides valuable insights for further studies on pollen functionality.

The starting point for every viticultural and wine-producing country with respect to local grapevine varieties is their identification, inventory, preservation and development of genetic resources of those varieties. There are currently 224 grapevine va?rieties cultivated in Serbia for the purpose of commercial production of grapes and wine. Out of that number, 31 wine varieties are local. Vineyards under those varieties can be dif?ferentiated by their importance for production of grapes and wine, and by the level of their endangerment, that is, sustainability in conditions caused by climate changes. This paper presents the creation, that is, the modeling of the Method for Vineyard Sustainability Clas?wine grapevine varieties on grounds of their endangerment and sustainability, based on 20 examined and categorized individual vineyard sustainability parameters; to carry out comsification (MVSC). The purpose of MVSC classification is: to valorize vineyards with local prehensive classification into one of the four established vineyard sustainability classes (Class A - very endangered vineyards, Class B - endangered vineyards, Class C - sustainable vineyards and Class D - very sustainable vineyards); spatial identification and presentation of vineyards based on determined vineyard sustainability class through application of GIS technology; and finally, application of Network Analysis (NA), prioritization of examined parameters and, therefore, vineyards. A total of 10,402 vineyards under local grapevine wine varieties were used for modeling, and it was determined that 29 vineyards with the total surface of 1.2 hectares should be classified in Class A, while 2,883 vineyards with the total surface of 158.2 hectares should be classified in Class B. With respect to the strength of 20 individual vineyard sustainability parameters, it was determined that the parameter Structure of the vine rootstock (SVR) has the greatest impact, and priority in selection of vineyards in different sustainability classes should be given to vineyards without rootstocks. In accordance with the scientific justification of obtained results, the MVSC enables comprehensive clas?sification of the potential for sustainability of genetic resources of local grapevine varieties in Serbia, and it can be applied in other countries and wine-growing areas, as well as to other groups of grapevine varieties.

Self-incompatibility presents one of the challenges in modern fruit production. It can be correlated with a lower yield of self-incompatible cultivars which also demand the planting of the pollinisers. The aim of this work was to investigate the phenomenon of incompatibility and its influence on fertilization success in quince (Cydonia oblonga Mill.), using the cultivars ‘Leskovacka’, ‘Vranjska’, ‘Morava’, ‘Pazardzijska’, ‘Hemus’, ‘Asenica’, ‘Portugal’ and ‘Triumph’. Incompatible pollen tubes were determined by using fluorescence microscopy. In two types of pollination (self-pollination and open pollination) pollen tubes showed signs of incompatibility, mostly in the upper third of the style. The most common sign of incompatibility is the formation of swelling at the tip of a pollen tube. Also, sometimes twisted, bifurcated, and short and thickened pollen tubes along their entire length are formed. The incompatibility was significantly more pronounced in the self-pollination than in the open pollination variant in all tested cultivars. The highest number of incompatible pollen tubes in both pollination types was present in the cultivar ‘Pazardzijska’, while the lowest number was present in the cultivars ‘Leskovacka’ and ‘Vranjska’. The appearance of incompatibility affected the degree of fertilization in quince. The results showed that only ‘Leskovacka’ and ‘Vranjska’ are self-compatible, while other studied cultivars (‘Morava’, ‘Pazardzijska’, ‘Hemus’, ‘Asenica’, ‘Portugal’ and ‘Triumph’) are self-incompatible. The results provide a good background for the future research of reproductive biology and also for adequate management of the quince orchards.

This paper presents the results on the study of promising vine hybrids in the Nis wine-growing region. The following promising vine hybrids were obtained from three different crossing combinations: NI 11-92 (Prokupac x Gamay Noir), NI 8-92 (Smederevka x Traminer Savagnin rose), and NI 2-92 (Smederevka x Riesling Rhine). The hybrids were created in the “Centre for Viticulture and Winemaking” in Niš. The tested hybrids differed in their cropping potential, grape yield and quality, chemical composition and sensory evaluation of the wine.