Surface sterilization is the most important step in preparation of explants for micropropagation, because controlling fungal and bacterial contamination of woody plant from field sources is very difficult. Six sterilizing agents: sodium hypochlorite (NaOCl), calcium hypochlorite [Ca(ClO) 2 ], sodium dichloroisocyanurate (DICA), mercuric (II) chloride (HgCl 2), silver nitrate (AgNO 3) and hydrogen peroxide (H 2 O 2) were tested for sterilization of 'Oblačinska' sour cherry buds, by varying their concentration and time of exposure. The aim of this study was to establish best surface sterilization for in vitro propagation of 'Oblačinska' sour cherry. Aseptic cultures of 'Oblačinska' sour cherry were established from axillary buds which were placed in nutrient medium, supplemented with plants hormones 6-benzylaminopurine (BA), 1naphthaleneacetic acid (NAA) and gibberellic acid (GA 3). The results indicated that among these sterilizing agents silver nitrate (AgNO 3) at concentration of 1% for 20 minutes was the best for controlling the infection, whereas sterilization with sodium dichloroisocyanurate (DICA) at concentration of 1% for 10 minutes was not satisfactory.

Fruit skin colour plays a major role in quality assessment of food, significantly determining consumer`s choice. Colour of sour cherries depends on anthocyanins which are phenolic compounds (flavonoids) present in high amounts in fruits. The aim of this study was to determine a possible relation between polyphenols (total phenolics and anthocyanins) and colour parameters of fruit skin of sour cherries. The plant material used in this study was twenty two sour cherry genotypes from an orchard of Agricultural Institute Osijek. Total phenolics and anthocyanins contents as well as colour parameters (L*, a*, b*, h and C) of fruit skin were determined. Variability between sour cherry genotypes in total phenolics and anthocyanins as well as in colour parameters was revealed. Total polyphenols content varied from 462.7 to 1049.0 mg GAE/100 g of fresh weight, while total anthocyanins ranged from 160.1 to 495.6 mg CGE/100 g of fresh weight. A significant positive correlation was found between polyphenols and anthocyanins content. Total phenolics content had a significant negative correlation with colour parameters b* and h, while anthocyanins content negatively correlated with colour parameters L*, b* and h. According to the obtained results, genotypes Maraska, Heimanns Konservenweichsel and Rexelle are the richest genotypes in polyphenols and anthocyanins content

Freshly squeezed sour cherry (Prunus cerasus L.) juices of Maraska Brač (BR), Maraska MA (MA), Oblačinska 18 (18), Oblačinska Osječka (OS), Rexelle (REX), Heimann conserved (HEI), and Kelleris 16 (KEL) grown in different climate regions (Mediterranean and continental) in two consecutive harvest years were analyzed for quality and sensory properties. Obtained results showed that investigated sources of variation (cultivar, growing area, harvest year) significantly influenced physical, chemical, and sensory properties of tested juices. All juices had high soluble solids (SS) (17.26% to 25.89%), especially BR (24.19%), MA (25.89%), 18 (24.66%), and OS (23.61%). Juices also had considerable total phenols (TP) content (2.19 to 5.87 mg GAE ml−1) and antioxidant capacity (AC) (0.020 to 0.045 mmol TE mL−1) with BR, MA, REX, and HEI containing the highest amounts of bioactive compounds (BR = 5.87 mg GAE mL−1, MA = 5.68 mg GAE mL−1, REX = 4.42 mg GAE mL−1, HEI = 4.27 mg GAE mL−1). Sensory evaluation showed that all juices had satisfying sensory profiles with BR, MA, 18, OS, and KEL juices scoring particularly high (5.3 to 8.9 of 10) in desirable sensory properties (color intensity [CI], sour cherry taste [SCT], harmonious taste [HT], taste fullness [TF], sour cherry odor [SCO], and viscosity [V]) of fresh sour cherry cloudy juice. Juices from Mediterranean area achieved higher values for SS, pH, SS/TA ratio, TP, AC, SCT, HT, TF, SCO, and V compared to continental zone juices. Harvest year with higher temperatures and less rainfall also resulted in higher SS, pH, TP, and AC as well as stronger expression of desirable sensory properties. Practical Application The results of this study provide an insight into sour cherry potential for use in functional food products, including today's popular smoothies, since it is fruit rich with health contributing compounds and possesses desirable sensory characteristics (color intensity, sour cherry taste, harmonious taste, taste fullness, sour cherry odor, and viscosity) at the same time, which can differ due to cultivar, climate diversity as well as weather conditions.

The aim of this study was to determine how different locations, years and cultivars influenced polyphenol and anthocyanin content in fruits of different sour cherry cultivars (Prunus cerasus L.). Fruits of five sour cherry cultivars were harvested in two locations (Osijek and Zadar) over three consecutive years (2010, 2011 and 2012). Factorial ANOVA showed that year and location significantly influenced the accumulation of polyphenols and anthocyanins in sour cherry fruits. 2010 was the best year with 9.89 mg/g of polyphenols and 5.08 mg/g of anthocyanins on average. Although year and location revealed a strong influence, cultivar is the principal source of variation, as it is proved by the polyphenol content in the range from 5.89 to 10.78 mg/g and the anthocyanin content in the range from 3.15 to 4.76 mg/g. Cv. Maraska appears to be the most significant source of bioactive compounds, while cvs. Heimanns Konservenweichel and Rexelle gave very similar but significantly lower contents of polyphenols and anthocyanins than cv. Maraska. Cv. Oblačinska had significantly the lowest contents of investigated bioactive compounds.

Istraživana je opskrbljenost, odnosno količina mikroelemenata: bakar, bor, mangan i cink u tlu, a u lišću jabuka: bakar, bor, mangan, cink i molibden u pet voćnjaka na području Slavonije i Baranje. U voćnjacima podignutim na tlima: lesivirano tipično, smeđe lesivirano, lesivirani pseudoglej na lesu, fluvijalno livadsko tlo i aluvijalno mineralno ne karbonatno, uzgojene su u gustom sklopu u obliku vretenastog grma sorte: Golden Delicious, Fuji, Jonaprinc, i Jonagold supra na podlozi M 9. Sorte jabuka su u dobi pune rodnosti, a postigle su dobru vegetativnu razvijenost. U voćnjacima se provodi intenzivna pomotehnika, agrotehnika i natapanje. Ustanovljeno je da je u svim voćnjacima, odnosno istraživanim tlima do dubine od 0-40 cm, razina bora, odnosno opskrbljenost borom vrlo niska do niska. Količine mangana kreće se u skupini bogate opskrbljenosti, osim u fluvijo livadskom tlu gdje je opskrbljenost niska. Količine bakra i cinka kreću se u skupini dobre opskrbljenosti u lesiviranom pseudogleju na lesu, aluvijalno mineralnom nekarbonatnom i fluvijo livadskom tlu. Opskrbljenost bakrom umjerena je u tipičnom lesiviranom i fluvijo livadskom tlu. Opskrbljenost cinkom niska je u smeđe lesiviranom tlu, a umjerena u fluvijo livadskom tlu. Lišće svih sorti jabuka u voćnjacima, na istraživanim tlima, dobro je opskrbljeno: bakrom, cinkom, manganom i molibdenom, a slabo do srednje borom.