Eleven red currant varieties (Ribes rubrum L.) cultured in Serbia were evaluated for some of their biochemical properties such as total phenolics, anthocyanins, ascorbic acid, invert sugar, soluble solid content, and acidity. The average amount of ascorbic acid varied from 50.5-71.6 mg/100 g FW, while concentration of invert sugars ranged from 6.0%-9.0%. The highest amounts of total phenolics and anthocyanins were detected in variety Redpoll (153.4 mg GAE/100 g FW and 19.3 mg/100 g, respectively). Red currants were processed to juice, and the phenolic and anthocyanin contents changed as a result of processing. Berries and juices were long-term stored at -18 °C and changes in phytochemicals were monitored. In berries, storage caused the decrease of ascorbic acid content up to 49%, and a general reduction of total phenolics was also noticed. In juices, total phenolics content increased after one year of storage. In both berries and juices total anthocyanins increased during storage by up to 85% and 50%, respectively. This study demonstrates that certain varieties, namely Redpoll, Jonkheer and London Market are good source of phytochemicals, retaining the nutritional value during processing and storage.

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Phenology can contribute to many scientific disciplines from climate change, biodiversity, agriculture and forestry to human health. The knowledge of timing of phenological events and their variability can provide valuable data for planning, organizing and timely execution of certain standard and special (preventive and protective) agricultural activities that require advanced information on the dates of specific stages of crop development. Mathematical models are the basic tools to predict the timing of phenological events. There are two types of phenological models: physiologically-based and statistical. Most of the existing models are statistical and serve to predict the onset of different phenophases according to the air temperature. These models are site- and species-specific and cannot be applied to a wide range of species and climatic conditions

The European pear psylla, Cacopsylla pyri L. (Hemiptera: Psyllidae), is one of the most serious arthropod pests of pear. Since proper control of this pest is essential, better understanding of the complex plant-pest relationship is mandatory. This research deals with constitutive polyphenolic profiles in leaves of 22 pear cultivars of diverse origin (P. communis, P. pyrifolia, and P. pyrifolia × P. communis) and different resistance to psylla. The study was designed to show which differences in the polyphenolic profile of leaves from resistant and susceptible pear cultivars could be utilized as information in subsequent breeding programs. The results demonstrated that the leaves of Oriental pear cultivars contained much higher amounts of p-hydroxybenzoic acid, ferulic acid, aesculin, and naringin, that, together with detected 3-O-(6″-O-p-coumaroyl)-hexoside, apigenin, apigenin 7-O-rutinoside, and hispidulin, indicated a clear difference between the species and might represent phenolics responsible for psylla resistance.

Plants shaded by nets in both years of cultivation had lower damage to leaves and berries and percentage of loss of yield, and usage of the net would be economically advantageous to growers. Fruit of blackcurrant cultivars grown in shading conditions still represent a good source of valuable nutritive and biologically active compounds.