FIRST RECORD OF THE JAPANESE GRAPE LEAFHOPPER ARBORIDIA KAKOGAWANA (HEMIPTERA: AUCHENORRHYNCHA: CICADELLIDAE: TYPHLOCYBINAE) IN SERBIA

The manuscript encloses the first finding of the leafhopper Arboridia kakogawana (Hemiptera: Auchenorrhyncha: Cicadellidae: Typhlocybinae) in Serbia. On total of four sites in Vojvodina, identification based on the morphological characters gave us data on the presence of this allochtonous species that was previously detected in Romania and Crimean peninsula. Arboridia kakogawana is known as the grapevine pest and it was observed in Serbia on two localities on damaged grapevine plants expressing characteristic symptoms of its presence such as intensive chlorotic patches. Individuals were collected using entomological nets and light traps

Cixiidae) and on epidemiological transmission routes of 'Candidatus Phytoplasma solani'

Hyalesthes obsoletus, vektor biljnog patogena 'Candidatus (Ca.) Phytoplasma solani', smatra se polifagnom štetočinom od ekonomskog značaja u centralnoj Evropi i Mediteranu. Istraživanjima sprovedenim u jugoistočnoj Evropi, koja gravitira centru arela vrste i gde je zabeležen značajan broj 'Ca. P. solani'- uslovljenih biljnih bolesti, utvrđeno je postojanje četiri asocijacije vektora sa biljkama dualnim domaćinima: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitex agnus-castus (Vac) i Crepis foetida (Cf). Populaciono-genetičkim analizama mitohondrijskih i nuklearnih markera (mikrosatelita) utvrđena je kriptična diferencijacija simpatričkih (uključujući sintopske) i geografski udaljenih H. obsoletus populacija na tri filogenetičke linije uslovljene biljkom domaćinom: (1) Ca-Ud, (2) Vac i (3) Cf. Pored jasne diferencijacije na mitohondrijskim genima (1.1% - 1.5%) i mikrosatelita koji potvrđuju izdvajanje populacija u jedan od tri klastera prema biljci domaćinu (pripadnost >90%), podršku za izdizanje genetičke divergencije H. obsoletus sensu lato na nivo kriptične specijacije daje registrovana distanca u odnosu na morfološki najsrodniju vrstu - Hyalesthes thracicus (2.1% - 3.3%). Posledice specijalizacije i diferencijacije H. obsoletus sensu lato prema biljkama domaćinima na epidemiologiju 'Ca. P. solani' procenjene su multigenskom karakterizacijom izolata fitoplazme detektovanih (1) in situ u prirodnim epidemiološkim sistemima mediteranskih vinograda i (2) eksperimentima unakrsne inokulacije biljaka putem prirodno inficiranih populacija vektora. Potvrđena je osnovna epidemiološka divergencija 'Ca. P. solani' na tuf-a/-ab i tuf-b cikluse vezane za Ud i Ca uz ukrštanje sa Vac-uzrokovanom tuf-b epidemiologijom i utvrđena kompleksnost tuf-b epidemiologije u kojoj učestvuje i treća genetička linija vektora, H. obsoletus ex Cf, kao i sama biljka dualni domaćin - C. foetida.The cixiid planthopper Hyalesthes obsoletus is generally considered as a polyphagous vector of 'Candidatus (Ca.) P. solani' associated with numerous wild and cultivated plants in central Europe and Mediterranean. Research conducted in southeastern Europe, the distribution centre of H. obsoletus and the area of most 'Ca. P. solani'-inflicted crop diseases, points toward specific dual host-plant associations with: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitex agnus-castus (Vac) and Crepis foetida (Cf). Population-genetic analysis of mitochondrial and nuclear genetic markers (microsatellites) have revealed cryptic differentiation between sympatric (including syntopic) and geographically distant H. obsoletus populations into three phylogenetic lineages delineated by host-plant preference: 1) Ca-Ud, 2) Vac i 3) Cf. Cryptic species diversification within H. obsoletus sensu lato is supported by the genetic divergence of mitochondrial genes (1.1% - 1.5%), microsatellites that confirm population clustering into three genetic groups associated with specific host-plant (average assignment >90%) and genetic distances among host-associated H. obsoletus metapopulations comparable to the most closely related, morphologically distinguishable species - Hyalesthes thracicus (2.1% - 3.3%). Consequences of the H. obsoletus sensu lato differentiation on the epidemiology of 'Ca. P. solani' are assessed by multilocus genotyping of the phytoplasma isolates detected (1) in situ in natural epidemiological systems of the Mediterranean vineyards and (2) plant inoculation experiments using naturally infected vector populations. Basic 'Ca. P. solani' epidemiological divergence into tuf-a/-ab and tuf-b cycles, each associated with Ud and Ca, respectively, is confirmed with evidences of intermixing Vac-induced tuf-b epidemiology, while complexity of the tuf-b epidemiology is further evidenced through influence of the third genetic lineage of the vector H. obsoletus ex C. foetida and its dual host-plant

Molekularna karakterizacija 'Candidatus Phytoplasma solani' na celeru: studija u Futogu

‘Candidatus Phytoplasma solani’, known by its trivial name stolbur phytoplasma, is a plant pathogen infecting numerous crops in Serbia. Celery plants with prominent leaf yellowing and chlorosis, sporadically with tissue necrosis, were observed during august 2020 in Futog, situated in Novi Sad suburbia in Vojvodina. Total of 12 sampled celery plants, 8 symptomatic and 4 asymptomatic ones, were analysed for ‘Ca. P. solani’ presence. All symptomatic celery plants were infected with stolbur phytoplasma according to the stol11 gene detection and therefore were further subjected to multigene molecular characterization on three genes: tuf, stamp and vmp1. Combining molecular tools PCR/RFLP and sequencing reviled two ‘Ca. P. solani’ multilocus genotypes in celery: tuf-b/Rqg31/V14 and tuf-b/Rpm35/V14, present in 4 samples each. Obtained results of the strain genotyping are in concordance with previous data on the ‘Ca. P. solani’ diversity on celery, but supplemented with genotyping of the vmp1 gene. Outbreak of stolbur phytoplasma in the assessed locality in Futog is linked to tuf-b epidemiological cycle correlated in Serbia mainly with weed Convolvulus arvensis which was present in the subjected celery plot, and could have been the phytoplasma inoculum source. Visual evaluation of the symptom occurrence suggests on 10-15% of ‘Ca. P. solani’ affected celery plants scattered throughout the plot corresponding to the pathogen dispersal in crop by cixiid planthoper Hyalesthes obsoletus (Hemiptera: Auchenorrhyncha) associated with C. arvensis, main vector of stolbur phytoplasma in Serbia.‘Candidatus Phytoplasma solani’, poznata po trivijalnom nazivu stolbur fitoplazma, biljni je patogen koji inficira brojne kulture u Srbiji. Biljke celera sa izraženim žutilom i hlorozom listova, sporadično i sa nekrozom tkiva, uočene su u avgustu 2020. u Futogu, predgrađu Novog Sada u Vojvodini. Ukupno 12 uzoraka celera, 8 simptomatičnih i 4 asimptomatične biljke, analizirane su na prisustvo ‘Ca. P. solani’. Svi simptomatični uzorci su se pokazali inficiranim stolbur fitoplazmom na osnovu analize stol11 gena i dalje su molekularno okarakterisani na 3 gena: tuf, stamp i vmp1. Kombinacijom molekularnih tehnika PCR/RFLP i sekvenciranja utvrđeno je prisustvo dva ‘Ca. P. solani’ multigenska genotipa, tuf-b/Rqg31/V14 i tuf-b/Rpm35/V14, prisutnih u po četiri uzorka. Dobijeni rezultati genotipizacije uzoraka stolbur fitoplazme odgovaraju prethodnim podacima o diverzitetu ovog patogena na celeru u Srbiji i dopunjeni su sa genotipizacijom vmp1 gena. Pojava stolbur fitoplazme u Futogu je vezana za tuf-b epidemiologiju, koja uglavnom izvire iz korovske vrste Convolvulus arvensis (poponac), koja je bila prisutna u istraživanom zasadu celera i mogla je biti izvor inokuluma. Vizuelna procena pojave simptoma pokazala je 10-15% prisustva simptomatičnih biljaka celera, nepravilno raspoređenih unutar zasada što ukazuje da je odgovorni vektor najverovatnije cikada Hyalesthes obsoletus (Hemiptera: Auchenorrhyncha) asocirana sa poponcem, najznačajniji vektor stolbur fitoplazme u Srbiji

REVEALING THE PRESENCE OF THE EAST ASIAN LEAFHOPPER TAUTONEURA POLYMITUSA (HEMIPTERA: AUCHENORRHYNCHA: CICADELLIDAE: TYPHLOCYBINAE) IN SERBIA THROUGH DNA BARCODING

After the first observations of cicadas of the subfamily Typhlocybinae (Hemiptera: Auchenorrhyncha: Cicadellidae), a specific white-orange-red coloration in Zrenjanin and Melenci in 2017 and 2018, four females of the same habitus were collected in August 2019 in Belgrade and Special Nature Reserve “Deliblato Sands”. External morphology analyzes indicated that they are most similar to the East Asian invasive species present in Europe, Tautoneura polymitusa Oh & Jung 2016. Due to the lack of sampled males, reliable species determination required the use of molecular methods. Since no nucleotide sequences of the barcoding region of the COI gene of the T. polymitus species are available in gene banks, specimens of males collected in Budapest at the site of the first find of the species in Europe were attached to the genetic identification. After successful multiplication and sequencing of the COI barcoding region, 100% genetic matching of the sequences of the analyzed females from Serbia and males from Hungary was determined. The obtained results confirm the presence of allochthonous cicada T. rolymitus in Serbia and indicate the importance of the barcoding method which in the context of biodiversity research successfully overcomes sampling problems such as small number of specimens or absence of males

Rubbery taproot disease (RTD) severe threat for sugar beet production in Central Europe

Rubbery taproot disease (RTD) appearance and symptoms have been described in Bulgaria, Romania and Serbia more than 60 years ago. At that time disease symptoms were associated with abiotic factors (drought). Latest researches about RTD reveal that Candidatus Phytoplasma solani is the causing agent of the disease and the presence of the disease also in Croatia, Hungary and Slovakia. After declining of the plants, roots are prone to rotting due to the activity of saprobes. Symptoms and the progress of the disease differ depending on climatic conditions. The first symptoms usually start appearing by the end of July and beginning of August. In wet years yellowing of the oldest leaves and relatively slow progress of the beet deterioration can be observed on the edges of sugar beet fields. In dry years, because of the drought, oldest leaves are being discarded very fast and the first visible symptom of the disease is a loss of turgor in young leaves during the hottest part of the day. If dry conditions continue, all leaves become necrotic, which leads to the complete decline of the plant. Taproots of diseased plants wilt, become rubbery, and stay without any rot symptoms until complete plant decline. A yield loss in the same beet field varies spatially and is usually aggregated toward the edges. Epidemiological studies of the disease are in progress

Reptalus quinquecostatus (Dufour, 1833) (Fulgoromorpha: Cixiidae) plant preferences in Serbia

Reptalus quinquecostatus (Dufour, 1833) is one of several species from the planthopper family Cixiidae that are known as vectors of plant pathogenic bacteria that can cause severe agroeconomic losses. Records of this species in Serbia by Horváth, Tanasijević and Janković refer to Oliarus quinquecostatus Dufour, 1883 [sic]. The species was described as inhabiting meadows and grasslands and reported as caught on Salix sp., Ulmus sp., Quercus sp., and Malva sylvestris. Modern-day molecular identification of species, i.e. sequencing of cytochrome oxidase subunit 1 (COI) gene, revealed the presence of R. quinquecostatus nymphs in the rhizosphere of Koeleria macrantha (Poaceae family) in eastern Serbia. This cixiid has been found in Serbia on various crops affected by ‘Candidatus Phytoplasma solani’: corn, grapevine, potato, and most recently, sugar beet. The occurrence on sugar beet was first reported in 2020 in northern Serbia when its population was aggregated on a boundary strip with several weeds: Convolvulus arvensis, Chenopodium album, Amaranthus retroflexus, Ambrosia artemisiifolia etc. During the 2021–2022 survey, the presence of R. quinquecostatus on sugar beet was confirmed on other localities in Serbia. Moreover, its populations were recorded on parsnip, tobacco and corn. Prunus spinosa and Crataegus sp. in microhabitats permeating arable land were also found preferable for R. quinquecostatus adults. Its several populations on different hosts were repeatedly sampled in June–July 2022. Populations on P. spinosa and Crataegus sp. were highly abundant and infected with ‘Ca. P. solani’, whereas in the agroecosystems, R. quinquecostatus is present in mixed population with R. panzeri, displaying minor precedence in the emergence of adults. Data on R. quinquecostatus plant preferences in Serbia support the polyphagy that has been previously reported throughout Europe. Since the genus Reptalus Emeljanov, 1971 has recently undergone nomenclatural and taxonomic revision, the use of the valid species name and proper morphological species identification, which in some cases should be supplemented with molecular tools, are crucial in biodiversity and insect pest research

Morphology versus DNA barcoding: two sides of the same coin. A case study of Ceutorhynchus erysimi and C. contractus identification

Genotyping of 2 well-known weevil species from the genus Ceutorhynchus (Coleoptera: Curculionidae) distributed in west Palearctic, C. erysimi and C. contractus, revealed phenotype versus genotype inconsistencies in a set of 56 specimens (25 C. erysimi and 31 C. contractus) collected from 25 locations in Serbia and Montenegro. An analysis of the mitochondrial cytochrome oxidase subunit I gene (COI), widely used as a barcoding region, and a nuclear gene, elongation factor-1 alpha (EF-1 alpha), revealed stable genetic divergence among these species. The average uncorrected pairwise distances for the COI and EF-1 alpha genes were 3.8%, and 1.3%, respectively, indicating 2 genetically well-segregated species. However, the genetic data were not congruent with the phenotypic characteristics of the studied specimens. In the first place, C. erysimi genotypes were attached to specimens with phenotypic characteristics of C. contractus. Species-specific PCR-RFLP assays for the barcoding gene COIwere applied for themolecular identification of 101 additional specimens of both morphospecies (33 C. erysimi and 68 C. contractus) and were found to confirm this incongruity. The discrepancy between the genetic and morphological data raises the question of the accuracy of using a barcoding approach, as it may result in misleading conclusions about the taxonomic position of the studied organism. Additionally, the typological species concept shows considerable weakness when genetic data are not supported with phenotypic characteristics as in case of asymmetric introgression, which may cause certain problems, especially in applied studies such as biological control programs in which the biological properties of the studied organisms are the main focus

Gumoza šećerne repe: dugo poznata, ali nedavno razjašnjena bolest

Pojava bolesti gumoze šećerne repe je primećena u Srbiji prvi put u Banatu i Bačkoj šezdesetih godina prošlog veka. Koren obolelih biljaka ispoljava različit stepen gumoze uz uvenuće listova. Iako je koren zaraženih repa inicijalno bez truleži, nakon uvenuća ili vađenja biljke, podložan je napadu saprofita. Simptomi gumoze repe su zabeleženi takođe u Bugarskoj i Rumuniji i primarno su dovođeni u vezu sa sušom. Narušene fizičke karakteristike korena obolele šećerne repe mogu dovesti do odbacivanja kompletnog prinosa od strane šećerana. Nakon perioda epidemijske pojave, bolest je bila sporadično prisutna. U periodu 2018-2020 godine gumoza je zabeležena u svim područjima gajenja šećerne repe u Srbiji, u epidemijskoj ili neepidemijskoj razmeri, ukazujući na periodičnu pojavu oboljenja što je karakteristično za bolesti izazvane stolbur fitoplazmom (‘Candidatus Phytoplasma solani’). Epidemijska pojava gumoze repe je u ovom periodu zabeležena i u Slovačkoj, a sporadična u Mađarskoj i Hrvatskoj. Šećerne repe sa simptomima gumoze sakupljene u navedenim zemljama su testirane na prisustvo stolbur fitoplazme primenom molekularnih metoda. Svi detektovani izolati fitoplazme su dalje genotipizirani na tri epidemiološki informativna gena tuf, stamp i vmp1. Prisustvo fitopatogene bakterije ‘Ca. Arsenophonus phytopathogenicus’, uzrokovača bolesti repe “basses richesses” (SBR) u Francuskoj, Nemačkoj i Švajcarskoj, takođe je testirano i nije utvrđeno u analiziranim uzorcima. Etiologija gumoze šećerne repe je rasvetljena u Novom Sadu (Rimskim Šančevima) gde je utvrđena asocijacija stolbur fitoplazme i tipičnih simptoma ove biljne bolesti

Diverzitet faune cikada podfamilije Deltocephalinae u agroekosistemima Srbije i potencijalni vektori fitoplazmi

Diversity of the cicads from the subfamily Deltocephalinae have been investigated in Serbia, over a period of 2004-2010 in vineyards on localities Vršac, Topola, Rajac and Jasenovik and maize fields of South Banat. Individuals of different species belonging to a subfamily Deltocephalinae were collected in plantations and crops, as well as from a surrounding vegetation. The most abundant species on all localities was Psammotettix alienus (Dahlbom, 1850). Less numerous species of the subfamily were Euscelis incisus (Kirschbaum, 1858), Neoaliturus fenestratus (Herrich-Schäffer, 1834) and Errastunus ocellaris (Fallén, 1806), while the percentage representation of Doratura impudica Horváth, 1897 was much lower. Among the representatives of the subfamily Deltocephalinae, species that have been recorded in the South Banat were Arocephalus languidus (Flor, 1861), Euscelis distinguendus (Kirschbaum, 1858) and Metalimnus steini (Fieber, 1869). In vineyards of Jasenovik as the most dominant species occurred N. fenestratus.Istraživanje diverziteta cikada podfamilije Deltocephalinae sprovedeno je u periodu od 2004. do 2010. godine u vinogradima na lokalitetima Vršac, Topola, Rajac i Jasenovik i usevima kukuruza u južnom Banatu. Jedinke različitih vrsta podfamilije Deltocephalinae su sakupljane u zasadima i usevima, kao i na okolnoj vegetaciji. Najbrojnija vrsta na svima lokalitetima bila je Psammotettix alienus (Dahlbom, 1850). Manje brojne vrste ove podfamilije bile su vrste Euscelis incisus (Kirschbaum, 1858), Neoaliturus fenestratus (Herrich-Schäffer, 1834) i Errastunus ocellaris (Fallén, 1806), dok je procentualna zastupljenost vrste Doratura impudica Horváth, 1897 bila znatno manja. Od predstavnika podfamilije Deltocephalinae, vrste koje su zabeležene u južnom Banatu su Arocephalus languidus (Flor, 1861), Euscelis distinguendus (Kirschbaum, 1858) i Metalimnus steini (Fieber, 1869). U vinogradima Jasenovika kao najdominantnija vrsta javljala se vrsta N. fenestratus

Field trial evaluation to RTD susceptibility/tolerance to RTD in Serbia: Is there a tolerance to RTD in current varieties?

Sugar beet is the second most important source for the sugar industry, particularly important in temperate climate zones of Central, West, and East Europe. However, its production has declined recently due to various factors of which the most important are subsidy cuts and the spread of various plant diseases. In the Pannonian Plain (Slovakia, Hungary, Romania, and Serbia), a disease called rubbery taproot disease (RTD) has been observed for along time. The variability in RTD symptoms and the extent of damage it causes have made its detection quite challenging, often leading to misdiagnoses as other diseases. However, the identification of Candidatus Phytoplasma solani as the cause of RTD has resolved the issue of its diagnosis. The latest outbreak in Serbia has had a significant economic impact on sugar beet production, prompting an urgent response to aid the industry and growers. In our study, conducted during the 2022 and 2023 seasons, we assessed the susceptibility/tolerance of thirty registered sugar beet hybrids in Serbia, evaluating their impact on root yield and quality in naturally infected experimental fields