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Forty Erwinia amylovora strains originating from different host plants and locations in Serbia and one strain from Montenegro were characterized by conventional, automated and molecular techniques. All strains were Gram-negative, nonfluorescent, facultative anaerobes, oxidase negative, levan positive, produced necrotic lesions followed by bacterial exudate on artificially inoculated immature pear fruits and caused HR on tobacco. Based on carbon source utilization, all strains tested with the Biolog system were identified as E. amylovora. Based on fatty acid profiles all tested strains clustered into three groups in which strains from north Serbia differed from strains isolated in central and south parts of the country. Restriction analysis of genomic DNA using XbaI and PFGE resulted in six different patterns differentiating the strains into six groups. Most of the investigated strains clustered in one group having the pattern type similar to Pt2 group described earlier as dominant in East Europe and the Mediterranean region. Two strains showed PFGE pattern similar to the previously described Pt3 pattern and one strain had pattern similar to Pt6. Based on size and number of the bands, new restriction patterns, assigned as Pt7, Pt8 and Pt9 were observed. PFGE results showed that E. amylovora population in Serbia is not homogenous and was possibly introduced from different directions. This is the first characterization of E. amylovora collection of strains from Serbia using fatty acid analysis and PFGE.

Forty Erwinia amylovora strains originating from different host plants and locations in Serbia and one strain from Montenegro were characterized by conventional, automated and molecular techniques. All strains were Gram-negative, nonfluorescent, facultative anaerobes, oxidase negative, levan positive, produced necrotic lesions followed by bacterial exudate on artificially inoculated immature pear fruits and caused HR on tobacco. Based on carbon source utilization, all strains tested with the Biolog system were identified as E. amylovora. Based on fatty acid profiles all tested strains clustered into three groups in which strains from north Serbia differed from strains isolated in central and south parts of the country. Restriction analysis of genomic DNA using XbaI and PFGE resulted in six different patterns differentiating the strains into six groups. Most of the investigated strains clustered in one group having the pattern type similar to Pt2 group described earlier as dominant in East Europe and the Mediterranean region. Two strains showed PFGE pattern similar to the previously described Pt3 pattern and one strain had pattern similar to Pt6. Based on size and number of the bands, new restriction patterns, assigned as Pt7, Pt8 and Pt9 were observed. PFGE results showed that the E. amylovora population in Serbia is not homogenous and was possibly introduced from different directions. This is the first characterization of E. amylovora collection of strains from Serbia using fatty acid analysis and PFGE.

Crown gall, caused by tumorigenic strains of Agrobacterium spp., is considered one of the most important diseases in stone fruit nurseries throughout the world. Since the crown gall disease has not been studied extensively in Serbia for more than 30 years, the objective of this study was to isolate, identify and characterize the bacterium associated with crown gall symptoms on one-year-old apricot trees. Samples were collected from a nursery in central Serbia and subjected to laboratory analysis. Bacteria were isolated from tumour tissue on yeast mannitol agar (YMA) and six gram-negative isolates were selected for further study. PCR assay using primers specific for virD2, virC, ipt and tms2 pathogenicity-associated plasmid genes revealed that isolates harbour Ti plasmids. All studied strains carrying Ti plasmids were classified as nopaline-type based on further molecular analysis. Using a multiplex PCR assay, targeting 23S rRNA gene sequences, and physiological and biochemical tests, five strains were assigned as A. rhizogenes/biovar 2 and the remaining one as A. tumefaciens/biovar 1. Identity of the strains was confirmed by sequence analysis of the 16S rRNA gene. In pathogenicity assay, all six strains caused tumour formation on inoculated carrot root discs, young tomato and sunflower plants.

In 2010, a serious outbreak of crown gall disease was observed on grapevines (Vitis vinifera L. cv. Cabernet Sauvignon) in several commercial vineyards located in the Vojvodina province, Serbia. Bacteria were isolated from the young tumor tissue on nonselective YMA medium and five representative strains were selected for further identification. Tumorigenic (Ti) plasmid was detected in all strains by PCR using primers designed to amplify the virC pathogenicity gene, producing a 414-bp PCR product. The strains were identified as Agrobacterium vitis using differential physiological and biochemical tests, and a multiplex PCR assay targeting 23S rRNA gene sequences. In the pathogenicity assay, all strains induced characteristic symptoms on inoculated tomato and grapevine plants. They were less virulent on tomato plants in comparison to the reference strains of A. tumefaciens and A. vitis.

Host range, plaque morphology, thermal inactivation point, genome size and restriction fragment patterns of ten bacteriophage isolates originating from soil, pepper seed and irrigation water collected from five localities in Serbia were studied. The bacteriophage isolates were selected based on their specificity to Xanthomonas euvesicatoria, causal agent of bacterial spot of pepper. The phages had similar plaque morphology, except for two isolates producing a plaque-surrounding halo in culture of X. euvesicatoria strain KFB 189. Four phage isolates were inactivated at 70 degrees C and six at 71 degrees C. All phages had genome size of approximately 22 kb and were differentiated into four types by their EcoRI and BamHI restriction fragment patterns. Examination of two phages by transmission electron microscopy classified them as A1 morphotype members of the Myoviridae family, order Caudovirales. Although specific to X. euvesicatoria, the phages were differentiated into three groups based on their ability to lyse 59 strains of this bacterium. Adsorption rates and one-step growth curves were determined for each group representative phage isolates.

Antraknoza je destruktivna bolest plodova jagode u toplim i kontinentalnim klimatskim uslovima. Tokom 2004. godine, na 2 plantaže jagoda u blizini Valjeva, bilo je velikih gubitaka prouzrokovanih antraknozom. Dva izolata gljiva GG-6A i GG-JUP su izolovana iz stolona jagode, i plodova sa izraženim simptomima antraknoze. Na osnovu morfoloških i patoloških karakteristika, i PCR analize sa specifičnim prajmerima za referentne vrste, izolat GG-6A je identifikovan kao Colletotrichum gloeosporioides, a izolat GG-JUP kao C. acutatum. Ovo je prvi nalaz C. acutatum na jagodi u Srbiji. U cilju kontrole antraknoze jagode pet fungicida i njihovih kombinacija su primenjeni 4 puta tokom cvetanja. Najbolja zaštita plodova jagode je postignuta primenom fungicida Metiram + piraclostrobin (Cabrio top), Captan FL i Fludioksinil ciprodinil (Swich). Manje efektivni su bili Benomil (Benlate) i Krezoksim-metil (Stroby). Patogen se prenosi sadnim materijalom pa su fitosanitarne mere veoma važne u prevenciji bolesti., Anthracnose is a destructive disease of strawberry fruits in warm and continental climate. During 2004, in the vicinity of Valjevo, there were severe losses in two strawberry plantations due to fruit anthracnose. Two fungal isolates, GG-6A and GG-JUP were recovered from strawberry stolons and fruits showing severe anthracnose symptoms. Based on morphological and pathological characteristics, and PCR analyses with specific primers of reference species, isolate GG-6A was identified as Colletotrichum gloeosporioides, and GG-JUP isolate as C. acutatum. This is the first identification of C. acutatum in strawberry in Serbia. In order to control strawberry anthracnose, five fungicides and their combinations were applied four times during the flowering. The best fruit protection was achieved by fungicides Metiram + piraclostrobin (Cabrio top), Captan FL and Fludioksinil + ciprodinil (Swich). Less effective were Benomil (Benlate) and Krezoksim-metil (Stroby). Pathogen is transmitted by planting material, so phytosanitary measures are extremely important in preventing the disease.

Nova bolest jagode, opisana pod nazivom antraknoza, odnedavno je prisutna i u našoj zemlji. Antraknoza je destruktivna bolest plodova jagode u toplim i kontinentalnim klimatskim uslovima. Kod nas je prvi put zabeležena 2004. godine u okolini Valjeva. Na dve plantaže bilo je velikih gubitaka, te su morale biti preorane. Gljiva je izolovana iz zaraženih plodova i stolona. Na osnovu morfoloških i patogenih odlika i PCR analize sa specifičnim prajmerima za referentne vrste, sa jagode su izolovane i identifikovane dve vrte gljiva. Izolat sa stolona je identifikovana kao Colletotrichum gloeosporioides, a sa plodva kao C. acutatum. Ujedno, ovo je prvi nalaz C. acutatum na jagodi u Srbiji. C. acutatum je karantinski patogen u zemljama EU i nalazi se na A2 listi. Nakon otkrića kod nas, ovaj patogen je sa A1 prebačen na A2 karantinsku listu. Patogen se prenosi sadnim materijalom, te su fitosanitarne mere veoma važne u prevenciji bolesti., New strawberry disease known as anthracnosis had been recently discovered in Serbia. Anthracnosis is a destructive disease of strawberry fruits in warm and continental climate areas. In Serbia anthracnosis was first discovered near Valjevo in 2004. In some fields damage was so severe that plots had to be plowed. A fungus was isolated from diseased fruits and stolones. On the basis of morphological and pathogenic characteristics and PCR analyses using specific primers we were able to identify two species of fungies. First, isolated from stolones was identified as Colletotrichum gloeosporioides, and second one, isolated from fruits, as C. acutatum. This is the first report of C. acutatum on strawberry in Serbia. C. acutatum is a quarantine pathogen in EU and it is listed on A2 quarantine pathogen list. After it’s detection in Serbia the pathogen has been transferred from A1 to A2 list. The pathogen is transmitted by diseased propagating material and phytosanitary measures are of extreme importance for prevention of the pathogen.