Content of individual sugars, organic acids, total phenolics (TPH), some important phenolic compounds (kaempferol, myricetin, quercetin, and ellagic acid) and total antioxidant capacity (TAC) in the fruits of strawberry, raspberry and blackberry were studied. A comparison was made between cultivars and wild relatives of each species (Fragaria vesca L., Rubus idaeus L. and Rubus fruticosus L.). The main sugars found were fructose and glucose both in the fruits of wild species and the studied cultivars. Citric acid was determined to be the major organic acid in most of tested berries with the exception of blackberry cultivars, where malic acid was dominant. The content of individual phenolic compounds varied among the wild species, as well as among the studied cultivars. Ellagic acid content was higher in F. vesca, R. idaeus and R. fruticosus (122.5 mg/g FW, 12.71 mg/g FW and 61.7 mg/g FW, respectively) than that obtained in analyzed cultivars. Overall, TPH expressed higher values in the wild strawberry and blackberry species in comparison to the studied cultivars, and consequently, the highest levels of TAC were recorded in F. vesca (5.78 mg asc/ g FW), followed by R. fruticosus (4.95 mg asc/g FW). PRACTICAL APPLICATIONSIn recent years, both wild and cultivated berries have become very attractive for consumers because of potentially beneficial phytochemicals contained in these fruits. Fruit nutritional quality can be described by standard quality parameters (sugars and organic acids), and the analysis of antioxidant capacity influenced by specific related compounds. The importance of flavonoids and other phenolics have been suggested to play a preventive role in the development of cancer and heart disease. A significant positive correlation observed in this study between total phenolics and total antioxidant capacity indicate the need for the use of wild species in the breeding programs of small fruits, especially strawberry and blackberry, in order to increase their nutritive value and the health benefits. ISSN 0146-9428 Journal of Food Quality

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The aim of this study was to examine different methods for determining growing degree-day (GDD) threshold temperatures for two phenological stages (full bloom and harvest) and select the optimal thresholds for a greater number of apricot (Prunus armeniaca L.) cultivars grown in the Belgrade region. A 10-year data series were used to conduct the study. Several commonly used methods to determine the threshold temperatures from field observation were evaluated: (1) the least standard deviation in GDD; (2) the least standard deviation in days; (3) the least coefficient of variation in GDD; (4) regression coefficient; (5) the least standard deviation in days with a mean temperature above the threshold; (6) the least coefficient of variation in days with a mean temperature above the threshold; and (7) the smallest root mean square error between the observed and predicted number of days. In addition, two methods for calculating daily GDD, and two methods for calculating daily mean air temperatures were tested to emphasize the differences that can arise by different interpretations of basic GDD equation. The best agreement with observations was attained by method (7). The lower threshold temperature obtained by this method differed among cultivars from -5.6 to -1.7 degrees C for full bloom, and from -0.5 to 6.6 degrees C for harvest. However, the "Null" method (lower threshold set to 0 degrees C) and "Fixed Value" method (lower threshold set to -2 degrees C for full bloom and to 3 degrees C for harvest) gave very good results. The limitations of the widely used method (1) and methods (5) and (6), which generally performed worst, are discussed in the paper.

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Milatović D., Nikolić D., Đurović D., 2010. Variability, heritability and correlations of some factors affecting productivity in peach. Hort. Sci. (Prague), 37: 79-87.Factors affecting productivity in peach, such as flower density, initial and final fruit set by open pollination, and yield per m length of shoot were studied in 40 cultivars during a three-year period. Significant differences among cultivars were found for all studied properties. The coefficients of variability were the lowest for initial fruit set and then for final fruit set and flower density; while they were the highest for yield. The relatively high values of heritability were found for flower density and yield. Significant correlation coefficients were found between initial and final fruit set, flower density and yield, as well as between final fruit set and yield. In areas with a higher risk of freeze damage the cultivars characterized by higher flower density and fruit set should be grown because they can provide more consistent yield potential. At the same time, these cultivars require more intensive pruning and fruit thinning to achieve quality fruit.

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Thirty vineyard peach [Prunus persica (L.) Batsch.] genotypes were studied to determine the overall degree of polymorphism and to detect similarities among genotypes. The variation was observed for traits related to phenology, morphology, yield and fruit quality. Many fruit characteristics that are important to breeders are present in this collection. The majority of important correlations were determined between the characteristics representing fruit size (fruit width, fruit height, fruit weight and stone weight) and between those ones representing fruit quality (fruit attractiveness, taste, flavour and soluble solids content). Cluster and principal component analysis showed a considerable phenotypical diversity in the vineyard peach germplasm. Clustering of genotypes was in accordance with its purpose (fresh consumption or rootstocks production). Parameters with high discriminating values were those related to fruit size and fruit quality.

Pomological properties of 11 newly sweet cherry cultivars grafted on Colt rootstock were studied in the region of Macva over a three-year period (2010- 2012). An investigation has included phenological traits (flowering and maturing), the elements of productivity (number of flowers in an inflorescence, fruit set and yield), the most important fruit characteristics (physical, chemical and sensory), and fruit cracking index. Average time of flowering of tested cultivars was in the first and the second decade of April, while the maturing time was between 15 May (‘Early Lory’) and 20 June (‘Penny’). The highest yield was achieved by cultivars ‘Giorgia’, ‘Sunburst’, and ‘Crystalina’. Large fruit size was found in cultivars ‘Penny’, ‘Santina’, ‘Sunburst’, ‘Olympus’, and ‘Kordia’. The lowest susceptibility to fruit cracking was manifested in cultivars ‘Early Lory’ and ‘Giorgia’. Cultivars ‘Kordia’ and ‘Cristalina’ were given the highest sensory ratings. Overall, the best results were shown by medium-early season cultivar ‘Santina’, which can be recommended for commercial cultivation. In addition, the early-season cultivar ‘Early Lory’, and the late-season cultivar ‘Kordia’ can also be recommended for cultivation. [Projekat Ministarstva nauke Republike Srbije, br. TR 31063