Prvi nalaz erysiphae cichoracearum var. cichoracearum na kantarionu u Srbiji

In May and June 2006 severe incidence of powdery mildew symptoms in a plantation of St. John's-wort (Hypericum perforatum L.) that has been cultivated as a medicinal plant at experimental fields of Institute for Medicnal Plant Researchin (Pančevo, Serbia) was observed. In September of the same year numerous clestothecia of the pathogen were formed on spontaneous plants of St. John's-wort at Vlasina Mounti (locality Vlasina Lake). White mycelial petchs (approximately 5 mm in diameter) were observed on leaves, leaves petals and stems. At the end of summer mycelia covered leaves completely which and necroted and fall down before the end of vegetation, so such diseased plants were completely unusefull as herb drug. According to morphological features the fungus was determinated as Erysiphe cichoracearum var. cichoracearum. Powdery mildew pathogens have not previously been reported on St. John's-wort in Serbia.Tokom maja i juna 2006. godine primećena je jaka pojava pepelnice na kantarionu (Hypericum perforatum L.) koji se plantažno gajio na komercijalnim zasadima Instituta za proučavanje lekovitog bilja u Pančevu. Tokom semptebra iste godine zapažene su brojne kleistotecije teleomorfa patogena na spontanim biljkama kantariona na Vlasini (Vlasinsko jezero). Bela micelijska navlaka javlja se na listovima, lisnim drškama i stablu. Krajem leta micelija prekriva celu površinu lišća, koje nekrotira, suši se i otpada, tako da su obolele biljke kantariona potpuno neupotrtebljive kao biljna droga. Na osnovu morfologije patogena gljiva je determinisana kao Erysiphe cichoracearum var. cichoracearum. Prouzrokovači pepelnice na kantarionu do sada nisu bili opisani u Srbiji

Detekcija XIIA grupe fitoplazmi sorte župljanka u župskom vinogorju RFLP analizom 16s rDNA sekvenci

'Bois noir' (BN) is an important grapevine disease associated with phytoplasmas belonging to ribosomal subgroup 16SrXII-A. Phytoplasmas cause diseases in several hundred plant species. The number of infected cultivars is growing each year and it is important to follow the spreading of the phytoplasma in the different regions and identify which strains are present in specific regions on specific cultivars. Phytoplasmas are identified and classified based on direct sequencing of phytoplasma 16S rDNA or the 16S to 23S intergenic spacer region, but this approach is not always practical when a large number of unknown phytoplasmas is to be analyzed. Classification by RFLP analysis has provided a simple and rapid method that can be used to differentiate and identify a large number of unclarified phytoplasmas. Our objective was to investigate presence of phytoplasmas of 16SrXII-A group (Stolbur) in Zupa vineyard region. Detection was based on RFLP analysis of 16s rDNA sequences using four restriction enzymes: Tru1I, AluI, KpnI and TaqI. We identified phytoplasmas of XIIA group on two of three investigated cultivars (Zupljanka and Frankovka, but not on Plovdina) in the Zupa vineyard regions (Gornje Rataje and Tules locality). This is the first report of Stolbur phytoplasma on cv. Zupljanka in Zupa region.'Bois noir' (BN) je značjna bolest vinove loze izazavana fitoplazmama 16SrXII-A grupe. Fitoplazme izazaivaju bolesti kod nekoliko stotina biljnih vrsta. Ovaj broj se povećeva svake godine, pa je veoma značajno pratiti širenje fitoplazmi u različitim regionima i utvrditi koji izazivač je prisutan u nekom regionu i na određenoj sorti. Identifikacija i klasifikacija fitoplazmi bazirana je na sekvenciranju 16S rDNA ili intergenskog regiona 16S - 23S, ali ovaj metod se retko primenjuje na analizu velikog broja uzoraka. Primena RFLP analize omogućava brzo i jednostavno detektovanje, diferenciranje i klasifikaciju velikog broja fitoplazmi. Cilj ovog rada je detektovanje fitoplazmi 16SrXII-A grupe (Stolbur) u Župskom vinogorju. Detekcija je izvršena RFLP analizom 16s rDNA sekvenci korišćenjem restrikcionih enzima: Tru1I, AluI, KpnI and TaqI. Identifikovane su fitoplazme XIIA grupe na dve od tri ispitivane sorte (na Župljanki i Frankovki, ali ne na Plovdini) u Župskom vinogorju (lokaliteti Gornje Rataje i Tuleš ). U ovim istraživanjima je prvi put dokazano prisustvo Stolbur fitoplazme na sorti Župljanka u Župskom regionu

Antifungalna aktivnost Pseudomonas chlororaphis Q16 prema Sclerotinia sclerotiorum poreklom sa različitih lekovitih biljaka

Phytopathogenic fungi Sclerotinia sclerotiorum is very destructive pathogen of the stem of many medicinal plants. Because the use of pesticides is forbidden during production of medicinal plants, presence of S. sclerotiorum may produce serious loss. The use of PGP (Plant Growth Promoting) bacteria, for which have been demonstrated to show antifungal activity with varying degrees of antagonism, gives protection to medicinal plants. The antifungal activity of different fractions of P. chlororaphis Q16 culture was examined on 6 representative isolates of S. sclerotiorum from medicinal plants: nettle, cumin, marshmallow, valerian and two strains of Echinacea. The highest efficacy of mycelial growth inhibition showed heat stabile antifungal factor with growth inhibition range from 52.75% (marshmallow isolate) up to 83.36% (isolate from E. purpurea). The inhibition of mycelial growth was similar for all S. sclerotiorum isolates when 24h culture was performed and ranged from 60.28% (cumin isolates) to 76.47% (nettle isolates).Fitopatogena gljiva Sclerotinia sclerotiorum je veoma destruktivni patogen stabla brojnih vrsta lekovitih biljaka. Kako u proizvodnji lekovitih biljaka nije dozvoljena upotreba pesticida, prisustvo ovog patogena prouzrokuje ozbiljne štete. Primena PGP (Plant Growth Promoting) bakterija, kao antagonista S. sclerotiorum, omogućuje zaštitu lekovitih biljaka. U ovim istraživanjima je ispitana aktivnost soja Pseudomonas chlororaphis Q16, pripadinka vrste koja spada među najefikasnije antagoniste S. sclerotiorum. Antifungalna aktivnost različitih frakcija kulture P. chlororaphis Q16 ispitivana je na 6 reprezentativnih izolata S. sclerotiorum poreklom sa različitih lekovitih biljaka: koprive, kima, belog sleza, odoljena i 2 vrste Echinacea. Najefikasnija je bila primena termostabilnih antifungalnih metabolita, frakcije koja je inhibirala porast micelije od 52,75% (izolata sa belog sleza) do 83,36% (izolata sa E. purpurea). Najujednačenija inhibicija porasta micelije ispoljena je primenom kultura starih 24h: od 60,28% (izolata sa kima) do 76,47% (izolata sa koprive)

Fitoplazmoze vinove loze

Phytoplasmas of grapevine are a group of harmful pathogens known as a yellowing type . On the grapevine stems affected by phytoplasma the following pathological cahges are observed: yellowing/reddening of the leaves, wilting and triangle-shaped laminae rolling, drying of flowers and clusters, withering and bit-ter taste of berries, unlignificated and rubbery canes and their freezing during win-ter, as well as decline and death of vines. All of these symptoms, especially the ones affecting flower and grapes lead to a significant reduction in the grape yield and poor quality wine. The yield reduction per plant/vine can be as high as 97%. The plants affected by the phytoplasmas stay infeccted permanently. Any plant protection measures applied, need to be preventive.Fitoplazmoze vinove loze su grupa vrlo raširenih štetnih oboljenja tipa žutila, čiji su prouzrokovači fitoplazme. Kod čokota obolelih od fitoplazmoza registrovane su kao najznačajnije sledeće patološke promene: žutilo/crvenilo lišća, uvelost, povijanje prema naličju i trouglast izgled liski, venjenje i sušenje cvasti i grozdova, smežuravanje i gorak ukus bobica, nezdrvenjavanje i gumoznost lastara i njihovo izmrzavanje zimi, kao i sušenje i prevremeno uginjavanje čokota. Ove promene, a posebno one koje se ispoljavaju na cvastima i grozdovima dovode do smanjenja prinosa grožđa i pogoršanja kvaliteta vina. Smanjenje prinosa po obolelom čokotu može iznositi i preko 97%. Čokoti vinove loze oboleli od fitoplazmi ostaju trajno zaraženi. Osnovne mere borbe protiv fitoplazmi vinove loze su preventivne mere

Primena DTBA i ELISA metode u dokazivanju virusa uvijenosti lista vinove loze-1

Grapevine leafroll syndrome is caused by a complex of up to nine different Grapevine leafroll-associated viruses (GLRaV-1-9). Many methods, including indexing, serological and molecular procedures, have been developed for the detection of GLRaV. However, due to the low concentration of the virus in plants a method with improved sensitivity and with the capacity to detect is required. In this study plants were tested for Grapevine leafroll virus (GLRaV) by visual examination, enzyme-linked immunosorbent assay (ELISA) and direct tissue-blotting assay (DTBA). Tissues were homogenized for use in a double antibody sandwich ELISA system and then blotted on a nitrocellulose membrane for DTBA. Comparison of DTBA with ELISA and with visual plant symptoms suggest that DTBA can be used with the same accuracy as ELISA for detecting GLRaV-1 in leaf tissue.Sindrom uvijanja lista vinove loze je oboljenje koje prouzrokuje grupa virusa koja se naziva Virusi vezani za uvijanje lista vinove loze (GLRaV-1-9). Više različitih metoda je razvijeno za detekciju ove grupe virusa, kao što su indeksiranje, serološke i molekularno biološke metode. Zbog relativno male koncentracije virusa u zaraženoj biljci potrebno je pronaći metodu koja ima najveću osetljivost pri njegovoj detekciji. U ovom radu u cilju detektovanja virusa GLRaV, ispitivane biljke su pored vizuelnog pregleda obrađivane i pomoću ELISA i DTBA metoda. Poređenjem ELISA i DTBA metode na simptomatičnim biljkama utvrđeno je da se ove dve metode sa jednakom tačnošću mogu koristiti u otkrivanju GLRaV-1 u listu vinove loze

Fitoplazmoze lekovitih biljaka

A diversity and incresing economic importance of medicinal plants demand a need to study their diseases. Among them phytopathogenic fungi are of a considerable importance, and in the last decade, phytoplasma diseases. Phytoplasma are important obligate intracellular, insect - transmitted pathogenic agents, found inside the phloem, in particular in the sieve tube cells of many plant species. These plant pathogens are wall-less, non-cultivable prokaryotes belonging to the Mollicutes class. They are the smallest prokaryotic organisms of a varied shape and size (50-1000 nm in diameter) and visible under the electron microscope. Their genome is the shortest known of all prokaryotic organisms (680-1600 kb). The most cited and widely accepted system of identification is based on the similarity in the 16S ribosomal gene sequence as well as their biological characteristics. Phytoplasmas are associated with plant diseases in several hundred plant species, inclu­ding many important vegetable, fruit crops, ornamental and medicinal plants. Disease plants exhibit pathological changes (in plants) which are demonstrated through four ty­pical types of symptoms: (1) phyllody, (2) yellowing and reddening, (3) virescence and (4) proliferation of axillary buds or 'witch's broom'. Typical phytoplasma symptoms are confirmed on the following species of medicinal plants: Ehinacea purpurea, E. Angustifolia, Hypericum perforatum, H. barbatum, Plantago major, Saponaria officinalis, Digitalis purpurea, Origanum vulgare, Levisticum officina­le, Carum carvi, Trigonella foenum greacum, Melisa officinalis, Petroselinum sativum, Apium graveolens, Valeriana officinalis, Rubus fruticosus, Vaccinium myrtillus, Arnica montana, Calendula officinalis, Cichorium intybus, Salix alba and Chamomilla recutita. The presence of phytoplasma was detected using electron microscopy (TEM) in 5 species of medicinal plants in Serbia, and using molecular identification in order to identify phyto­plasma in other species. Two types of phytoplasma were identified on more than 20 species of the medicinal plants in Serbia: Stolbur phytoplasma (16SrXII group) and Clover yellow edge (16SrIII-B). There are very few qualitative and quantitative data on the changes in secondary metabolites af­fected by the phytoplasma and these data should be improved.Lečenje lekovitim biljem staro je koliko i čovečanstvo. Čak i danas, lečenje biljem ima svoju primenu i neprestano se razvija. Lekovite biljke predstavljaju skupoceno blago prirode kao sirovina za lečenje, kao hrana i predmet trgovine. U oblasti proučavanja prirodnih lekovitih sirovina postignuti su, do sada, veoma značajni rezultati, koji su uticali na povećanje interesovanja njihovog korišćenja u proizvodnji lekova. Gotovo da nema oblasti u savremenoj terapiji gde fitofarmaka nema primenu. Fitoterapija u širem smislu reci podrazumeva terapiju svim preparatima na bazi bilja. To mogu biti razni ekstraktivni preparati ili drugi galenski oblici definisanog sastava: kapsule, tablete, masti, sirupi i dr. Zastupljenost vrsta lekovitog bilja u Srbiji čini oko 700 vrsta, što predtavlja preko 19 % od ukupne flore Srbije. Zvanično je registrovano oko 420 vrsta lekovitog bilja, a u prometu se nalazi oko 300 vrsta, od kojih najveći deo raste spontano u prirodi, a manji broj se gaji plantažno. Vrednost proizvodnje lekovitog i aromatičnog bilja procenjuje se na oko sedam miliona, a izvoz na oko četiri miliona dolara. Raznovrsnost, brojnost i sve veći ekonomski značaj lekovitih biljaka, nameće potrebu proučavanja njihovih bolesti, među kojima fitopatogene gljive zauzimaju značajno mesto, a poslednjih desetak godina sve veći značaj preuzimaju fitoplazmoze. Fitoplazme su obligatni intracelularni mikroorganizmi koji nastanjuju floem i to ćelije sitastih cevi različitih biljnih vrsta. U prirodi ih prenose insekti, vektori iz grupe cikada na perzistentan način. Fitoplazme su uglavnom okruglastog, ali promenljivog oblika i veličine (50-1000 nm u prečniku), koja im omogućava prolaz kroz sitaste ploče floema. Vidljive su pod elektronskim mikroskopom. Predstavljaju najsitnije prokariotske mikroorganizme, bez ćelijskog zida, a obavijene su omotačem, po čemu se i razlikuju od bakterija. Sadrže ribozome sa ribonukleinskim kiselinama i dvospiralnu dezoksiribonukleinsku kiselinu. Imaju najmanji genom, koji je poznat, kod prokariotskih organizama (680-1600 kb). Ni jedna fitoplazma nije, do sada, odgajena kao čista kultura na veštačkoj podlozi, pa je zbog toga njihova identifikacija još uvek nesigurna i neprihvaćena. Najviše citiran i široko prihvaćen je sistem na osnovu sličnosti u sekvencama njihovog 16S ribozomalnog gena i bioloških osobina. Fitoplazmoze karakteriše niz patoloških promena, a mogu se ispoljiti kroz četiri tipična tipa simptoma: (1) filodija, (2) žutilo i crvenilo, (3) ozelenjavanje ili virescencija i (4) proliferacije vršnih pupoljaka ili 'veštičine metle'. Na lekovitim vrstama u Srbiji tipični fitoplazmozni simptomi utvrđeni su na: Ehinacea purpurea, E. Angustifolia, Hypericum perforatum, H. barbatum, Plantago major, Sapona­ria officinalis, Digitalis purpurea, Origanum vulgare, Levisticum officinale, Carum carvi, Trigonella foenum greacum, Melisa officinalis, Petroselinum sativum, Apium graveolens, Valeriana officinalis, Rubus fruticosus, Vaccinium myrtillus, Arnica montana, Calendula officinalis, Cichorium intybus, Salix alba i Chamomilla recutita. Elektronskom mikroskopijom utvrđeno je prisusvo fitoplazmi u 5 vrsta lekovitih biljaka, a u ostalim vrstama primenom tehnika molekularne identifikacije. Dve vrste fitoplazmi su utvrđene na lekovitim biljkama u Srbiji: Stolbur fitoplazma (16SrXII grupa) i Clover yellow edge (16SrIII-B), na više od dvadeset vrsta lekovitih biljaka. Podaci o kvantitativnim i kvalitativnim promenama sekundarnih metabolita fitoplazmoznih lekovitih biljaka su oskudni, pa ih treba podspešiti

Efikasnost bakar-citrata u zaštiti vinove loze od bolesti

The control of Plasmopara viticola and Botrytis cinerea, two of the most dangerous pathogens on grapevine, requires frequent treatments with chemicals based on weather conditions. Numerous applications of fungicides have resulted in developing fungicide resistance. Active ingredients based on copper have been used very successfully for a long time to protect grapevines against these pathogens. Application of a copper citrate formulation with high degree dissociation at a very low concentration (1%) was evaluated in field trials. The efficacy of two concentrations of copper citrate, 0.5 and 1.0%, were tested against P. viticola on grapevine in three locations, and against B. cinerea in two locations during 2018. Our results demonstrated that the concentration of 1.0% copper citrate was highly effective against P. viticola (87.4%) and B. cinerea (63.7%), compared to standard treatment (90.6 and 53.1%), under a high level of infection.Zaštita vinove loze od prouzrokovača plamenjače vinove loze - Plasmopara viticola i sive truleži - Botrytis cinerea, je vrlo kompleksna i zahteva primenu većeg broja hemijskih tretmana, u skladu sa vremenskim uslovima. Učestala primena fungicida uslovljavala je pojavu rezistentnih izolata patogena na fungicide. Različite forme bakarnih jedinjenja primenjuju se u zaštiti vinove loze dugi niz godina prilično uspešno. Primena bakar-citrata - formulacije sa visokim stepenom disocijacije u niskoj koncentraciji (1,0%) ispitivana je u poljskim uslovima. Efikasnost dve koncentracije bakar-citrata - 0.5 i 1.0% je testirana u suzbijanju P. viticola i B. cinerea na vinovoj lozi na tri (dva) lokaliteta, tokom 2018 godine. Naši rezultati pokazuju da je ispitivana koncentracija od 1,0% bakar-citrata ispoljila zadovoljavajući efekat na P. viticola (87,4%) i B. cinerea (63,7%) u odnosu na primenjene standarde (90,6% i 53,1%) u uslovima visokih zaraza

Antifungalana aktivnost biljnih etarskih ulja i odabranih sojeva Pseudomonas spp. na Phomopsis theicola

Development of natural plant protection products as an alternative to synthetic fungicides is of significant importance regarding the environment. This study was carried out with an objective to investigate in vitro antifungal activities of several essential oils extracted from oregano, basil, myrtle and Turkish pickling herb, and the plant growth-promoting rhizobacteria in the genus Pseudomonas, against the phytopathogenic fungus Phomopsis theicola. Microdilution methods were used to determine the minimum inhibitory concentrations (MIC) of selected antimicrobial essential oils (EOs). All EOs exhibited significant levels of antifungal activity against the tested fungal isolates. The oregano EO was found the most potent one (MIC - 5.5 µg/mL), followed by basil (MIC - 75.0µg/mL), myrtle (MIC - 775 µg/mL) and Turkish pickling herb (MIC - 7750 µg/mL). Inhibition of Ph. theicola mycelial growth was observed for all tested Pseudomonas spp. strains. K113 and L1 strains were highly effective and achieved more than 60% of fungal growth inhibition using the overnight culture and more than 57% inhibition by applying cell-free supernatants of both strains. A future field trial with K113 and L1 cultures and cell-free supernatants, containing extracellular metabolites toward Ph. theicola, will estimate their effectiveness and applicability as an alternative to chemical protection of apple trees.U novije vreme intezivno se radi na razvoju bioloških sredstava za zaštitu bilja, koja bi se uvodila kao zamena za sintetičke fungicide. U ovom radu ispitivan je in vitro antifungalni uticaj nekih etarskih ulja (EU) i odabranih rizobakterija koje stimulišu rast biljaka iz roda Pseudomonas na fitopatogenu gljivu Phomopsis theicola. Minimalne inhibitorne koncentracije (MIC) etarskih ulja su određene mikrodilucionom metodom. Sva primenjena EU su ispoljila značajni antifungalni efekat na ispitivani izolat gljive. EU origana je ispoljilo najnižu MIC od 5.5±0.51 µg/mL, zatim ulje bosiljka od 75.0±5.7 µg/mL, mirte 775±45.0 µg/mL i turske kisele biljke od 7750±4.5 µg/mL. Proučavan je stepen inhibicije porasta micelije Ph. theicola primenom različitih sojeva Pseudomonas spp. sojevi K113 i L1 su ispoljili visoku efikasnost inhibicije od preko 60% primenom dvadesetčetvoročasovnih kultura i preko 57% primenom filtrata supernatanta. U narednim ogledima u polju primenom kulture i supernatanta K113 i L1, koji sadrže ekstracelularne metabolite, proceniće se njihova efikasnost i mogućnost korišćenja kao alternative hemijskim sredstvima u zaštiti jabuke od Ph. theicola

Application of semi-selective mediums in routine diagnostic testing of Pseudomonas savastanoi pv. phaseolicola on common bean seeds

Halo blight, caused by Pseudomonas savastanoi pv. phaseolicola (Psp), is considered to be an important bacterial disease on common bean (Phaseolus vulgaris L.) in Serbia. Use of pathogen-free seeds is one of the most effective control measures against this disease. The aim of this study was to evaluate a detection method for Psp on untreated common bean seeds (23 genotypes) from commercial crops grown within Serbia. Detection of this pathogen was made by plating onto the modified sucrose peptone (MSP) and Milk Tween (MT) semi-selective mediums from soaked whole common bean seed. Colonies growing on the MSP medium were light yellow, convex and shiny, whereas on the MT medium, they were creamy white, flat and circular. The pathogenicity of the obtained strains was confirmed by the inoculation of germinated bean seed. The isolates recovered from the seed assay were further confirmed to be Psp by using both Enzyme-linked immunosorbent assay (ELISA) and Polymerase Chain Reaction (Nested-PCR) detection methodologies. The International Seed Testing Association (ISTA) method selected for this work was found to be effective in detecting the presence of Psp in common bean seed. The bacterium Psp was detected in only two of the 23 seed samples analyzed by this method, which shows that the bacterium is not widespread in Serbia