Bakterioze kukuruza

Maize production intensity and economical importance in human and animal consumption, as well as in industrial processing, contributed to a permanent interest of plant pathologists in diseases affecting the crop production. Among numerous pathogens associated with maize not all of them represent serious threat. Maze pathogenic bacteria did not cause significant damage in maze production so far. However, intensive movement of maize germplasm may contribute to an increased pathogenicity of some pathogens on newly introduced genotypes not adapted to a local population of microorganisms. More than 10 bacterial species affecting maize were reported so far. They occurred mostly in specific ecological conditions such as high relative humidity, hot weather, and very often follow an insect damage of the plants. However, there were no severe outbreaks of maize bacterial diseases reported in Serbia so far. Therefore, in this paper we will present an overview of two potentially important bacterial species: Pantoea stewartii subsp. Stewartii - maize bacterial wilt causal agent; and Dickeya spp. - causing maize stalk bacterial rot. The first mentioned is a quarantine pathogen in Serbia, and Dickeya spp. were already reported as maize pathogens in this country.Intenzitet proizvodnje i ekonomski značaj kukuruza kao proizvoda za ljudsku i stočnu ishranu, ali i industrijsku preradu, doprineli su da bolesti kukuruza neprekidno budu predmet proučavanja fi topatologa. Ova biljna vrsta je domaćin brojnim mikroorganizmima. Ipak, ne predstavljaju svi patogeni kukuruza podjednaku opasnost. Fitopatogene bakterije za sada nisu ozbiljan problem u proizvodnji ovog useva. Međutim, intenzivna razmena genetskog materijala kukuruza širom sveta može imati za posledicu porast patogenosti pojedinih mikroorganizama, nastao usled uvođenja genotipova čija je osetljivost prema populaciji patogena u domaćoj proizvodnji nepoznata. U literaturi je do sada opisano desetak fi topatogenih bakterija parazita kukuruza. Njihova pojava se uglavnom uočava u specifi čnim ekološkim uslovima, kao što su visoka relativna vlažnost vazduha, povišena temperatura, a često je presudno prisustvo insekata vektora. Za sada, nijedna od opisanih vrsta ne pričinjava značajne štete kukuruzu u Srbiji. Ipak, zbog potencijalne opasnosti, navešćemo više informacija o: Pantoea stewartii subsp. stewartii - prouzrokovaču bakteriozne uvelosti kukuruza i Dickeya spp. - prouzrokovačima bakteriozne truleži stabljike kukuruza. Prva je karantinska vrsta za našu zemlju, dok su predstavnici roda Dickeya već opisani kao patogeni kukuruza u nas

Bakteriofagi kao baktericidi u zaštiti bilja

Control of plant pathogenic bacteria is a serious problem in production of many agricultural crops. High multiplication rate, adaptability and life inside plant tissue make bacteria unsuitable and inaccessible for most of control measures. Consequently, the list of bactericides available for plant protection is very short. Lately, biological control measures have been intensively studied as a potential solution of the problem. Investigation of bacteriophages, viruses that attack bacteria, is a fast-expanding area of research in plant protection. Several experiments have shown that they can be used as a very efficient tool for control of plant pathogenic bacteria. The fact that they are widespread natural bacterial enemies, simple for cultivation and management, host-specific, suitable for integration with other control practices, human and environment friendly, provide a great advantage for the application of phage's over other bactericides.Zaštita bilja od patogenih bakterija predstavlja značajan problem u poljoprivrednoj proizvodnji. Visoka stopa umnožavanja, prilagodljivost i život u unutrašnjosti biljnih tkiva čine bakterije veoma nepogodnim i nedostupnim za suzbijanje. Zahvaljujući tome, lista baktericida, koji se mogu primeniti u zaštiti bilja, veoma je kratka. Poslednjih godina, rešenje problema sve više se traži u primeni bioloških mera zaštite. Bakteriofagi, virusi koji parazitiraju bakterije, sve su češće predmet istraživanja fitopatologa. Eksperimentalno je pokazano da se mogu iskoristiti kao veoma efikasno sredstvo za kontrolu štetnih bakterija. Činjenice da su opšte rasprostranjeni prirodni neprijatelji bakterija, jednostavni za gajenje i održavanje, specifični prema domaćinu, pogodni za integraciju sa drugim merama zaštite, bezopasni po čoveka i druge činioce biosfere, daju im značajnu prednost nad drugim sredstvima baktericidnog dejstva

Bakteriozni rak vinove loze

Crown gall is considered one of the most important and widespread bacterial diseases of grapevine (Vitis vinifera L.). Disease is present in almost all grapevine-growing areas worldwide. Crown gall is an economically important plant disease of grapevine, especially in nurseries and newly established vineyards. Typical symptoms of grapevine crown gall disease include tumor formation on the aerial parts of host plants. Agrobacterium vitis is primary species causing this disease. A. vitis colonizes grapevine systemically and can persists latently in symptomless plant material. It is also detected as an epiphyte on grapevine and can survive in soil exclusively in association with host plants. Crown gall can be efficiently disseminated to distant geographical areas via international trade of propagation material, which is considered the main pathway of disease introduction and spread. In Serbia, crown gall was observed sporadically on grapevine, although it occurred with high incidence and severity in some years. Because there are no effective curative control measures, the disease is especially challenging to manage. Therefore, the disease management strategy is based on preventive measures. Use of pathogen-free planting material in areas with no history of the crown gall represents main prerequisite for the disease prevention. Biological control and production of resistant grape varieties are promising as future control measures.Bakteriozni rak smatra se jednim od najvažnijih i najrasprostranjenijih bakte-rioznih oboljenja vinove loze (Vitis vinifera L.). Ustanovljen je u gotovo svim zemljama gde se gaji vinova loza. Bakteriozni rak je ekonomski vrlo značajno oboljenje vinove loze, a posebno je ozbiljno u rasadnicima i mladim vinogradima. Tipični simptomi bakterioznog raka ispoljavaju se u vidu tumora na nadzemnim delovima vinove loze. Vrsta Agrobacterium vitis glavni je prouzrokovač ovog obo-ljenja. Patogen sistemično zaražava vinovu lozu i prisutan je u sprovodnom tkivu domaćina, a može biti latentno prisutan u asimptomatičnom biljnom materijalu. Takođe, patogen je detektovan i kao epifit na površini različitih organa vinove loze, kao i u rizosferi i zemljištu u blizini biljaka domaćina. A. vitis može biti raširen na velike udaljenosti putem naizgled zdravog sadnog materijala, što predstavlja najznačajniji način introdukcije i širenja bolesti. U Srbiji, bakteriozni rak se javlja sporadično, mada je u pojedinim godinama zabeležena jača pojava ovog obolje-nja uz visoku stopu zaraženih biljaka i izražene štete. Kontrola bakterioznog raka nije laka, s obzirom da ne postoje efikasne kurativne mere. Stoga se strategija zaštite prvenstveno zasniva na preventivnim merama. Korišćenje zdravog sad-nog materijala i zasnivanje vinograda na površinama koje nisu kontaminirane patogenom neizostavna je mera. Biološka kontrola i proizvodnja otpornih sorti predstavljaju obećavajuće mere kontrole u budućnosti

Pregled proučavanja bakterioza biljaka u Crnoj Gori

Plant production in Montenegro is becoming more important considering limited availability of land, climatic conditions and economic opportunities. The production profitability can be compromised by various plant pathogenic microorganisms such as fungi, bacteria, phytoplasmas, and viruses. Bacterial and phytoplasma incited diseases are the most devastating considering their spread and difficulty to control. In Montenegro, bacterial diseases of plants have not been sufficiently studied. However, several economically important bacteria were reported in the past. Erwinia amylovora, the causal agent of fire blight of pome fruits is widespread in the continental part of the country, causing significant damage and limiting production of pome fruits and susceptible ornamental plants. Pseudomonas syringae pv. syringae, the causal agent of citrus blast of mandarin, almost every year, depending on climatic conditions, causes the production losses along Montenegrian coast. Pseudomonas syringae, commonly known as a pathogen of stone fruits, was just studied as a pathogen of sour cherries. The presence of Xanthomonas arboricola pv. pruni on almond trees indicate the need to determine its possible presence in other host plants (peach, nectarine, plum, apricot). Agrobacterium tumefaciens was reported as causal agent of crown gall disease of grapevine. Considering vegetable bacterial diseases, the presence of Xanthomonas campestris pv. campestris, the causal agent of black rot and vascular bacterial disease, was confirmed on crucifers. On ornamental plants, Pseudomonas savastanoi pv. nerii was confirmed on oleander, while calla soft rot was caused by Pectobacterium carotovorum subsp. carotovorum.Biljna proizvodnja u Crnoj Gori dobija sve veći značaj s obzirom na zemljišne, klimatske i ekonomske prilike. Rentabilnost biljne proizvodnje mogu ugroziti različiti patogeni mikroorganizmi kao što su: gljive, bakterije, fitoplazme i virusi. Po značaju, rasprostranjenosti, ali i nemogućnosti uspješne kontrole, izdvajaju se oboljenja bakteriozne i fitoplazmozne prirode. U Crnoj Gori bakterioze biljaka još uvijek nisu dovoljno proučene. Među saopštenjima o pojavi biljnih oboljenja značajnijeg intenziteta prikazano je i nekoliko ekonomski veoma značajnih bakterija. Erwinia amylovora, prouzrokovao bakteriozne plamenjače jabučastih voćaka, široko je rasprostranjena u kontinentalnom dijelu Crne Gore, gde prouzrokuje značajne štete i predstavlja ozbiljnu prijetnju uspešnom gajenju jabučastih voćaka i osjetljivih ukrasnih biljka. Pseudomonas syringae pv. syringae, prouzrokovao bakteriozne paleži lišća mandarine, gotovo svake godine, u zavisnosti od klimatskih prilika, prouzrokuje štete na Crnogorskom primorju. Pseudomonas syringae, kao opštepoznat patogen koštičavih voćaka, proučen je samo kao patogen višnje. Utvrđeno prisustvo patogena Xanthomonas arboricola pv. pruni na bademu, nameće potrebu da se utvrdi eventualno prisustvo patogena i u drugim lokalitetima kao i na drugim domaćinima (breskva, nektarina, šljiva, kajsija). Agrobacterium tumefaciens prouzrokuje bakteriozni rak vinove loze. Od povrtarskih biljaka, na kupusnjačama je utvrđeno prisustvo Xanthomonas campestris pv. campestris prouzrokovača crne truleži i sudovne bakterioze kupusnjača. Na ukrasnom bilju, kao patogen oleandera utvrđen je Pseudomonas savastanoi pv. nerii prouzrokovao raka oleandera, dok bakterioznu vlažnu trulež kale prouzrokuje Pectobacterium carotovorum subsp. carotovorum

Bakterioze krompira - crna trulež prizemnog dela stabla ('crna noga') i vlažna trulež krtola krompira

Bacterial diseases are very common in potato crops, especially when weather conditions are favourable for the emergence and spread of infection. Bacteria belonging to the Pectobacterium and Dickeya genera, the causal agents of the blackleg and tuber soft rot of potato, are economically important pathogens that affect potato production worldwide, as well as in our country. According to recent classification, pectolytic bacteria, the pathogens of potato, have been differentiated as Pectobacterium atrosepticum, P. carotovorum subsp. carotovorum, P. carotovorum subsp. brasiliense, P. wasabiae and several Dickeya spp. The disease occurs on potato plants and tubers in the field, or during potato storage or transportation, thereby reducing yield and quality. The aim of this paper is to point to the distribution and economic importance of the blackleg and tuber soft rot of potato, as well as the characteristics of the pathogens. Information about symptoms and epidemiology of the disease are important for an accurate disease diagnosis and pathogen identification, contributing to the timely and successful protection strategy.Oboljenja bakteriozne prirode veoma su česta u usevima krompira, posebno kada vremenski uslovi pogoduju nastanku i širenju infekcije. Među ekonomski značajnim bakterijama koje ugrožavaju proizvodnju krompira u svetu i u našoj zemlji, izdvajaju se prouzrokovači crne truleži prizemnog dela stabla ('crna noga') i vlažne truleži krtola krompira, pripadnici rodova Pectobacterium i Dickeya. Prema najnovijoj klasifikaciji, pektolitičke bakterije, patogeni krompira, diferencirane su u vrste Pectobacterium atrosepticum, P. carotovorum subsp. carotovorum, P. carotovorum subsp. brasiliense, P. wasabiae i nekoliko Dickeya spp. Bolest se može pojaviti na biljkama i krtolama u polju ili na krtolama tokom transporta i u skladištu, umanjujući prinos useva i kvalitet krtola. Cilj ovog rada je da se prikaže rasprostranjenost i ekonomski značaj crne truleži prizemnog dela stabla i vlažne truleži krtola krompira, kao i osnovne karakteristike patogena. Poznavanje simptomatologije i epidemiologije oboljenja je od posebnog značaja za pravilnu dijagnozu oboljenja i identifikaciju patogena, što doprinosi pravovremenoj i uspešnoj zaštiti

Diferencijacija Pseudomonas syringae patogenih varijeteta poreklom iz koštičavih voćaka

Due to an overlapping host range, similar symptomatology and many common characteristics, Pseudomonas syringae pathovars originating from stone fruits can easily be misidentified. In order to select tests for rapid and efficient differentiation of P. s. pvs. syringae, morsprunorum and persicae, we studied the suitability and differentiating potential of some standard bacteriological and molecular methods. Differentiation of the strains was performed using LOPAT, GATTa and ice nucleation tests, nutrient sucrose broth growth and utilization of various carbon sources. PCR method enabled the detection of toxin-producing genes: syrB and syrD in P. s. pv. syringae, and cfl gene in P. s. pv. morsprunorum race 1. Syringomycin production by pv. syringae was confirmed in bioassay using Geotrichum candidum, Saccharomyces cerevisiae and Rhodotorula pilimanae as indicator organisms. Pathogenicity test on lemon and immature nectarine fruits, as well as on string bean pods, showed different intensity of reaction of the inoculated material which could separate pv. syringae from the other two pathovars. PCR-based repetitive sequences, Rep-PCR with REP, ERIC and BOX primers revealed different genetic profiles within P. syringae pathovars.Patogeni varijeteti Pseudomonas syringae poreklom sa koštičavih voćaka poseduju brojne zajedničke karakteristike u pogledu kruga domaćina, simptomatologije i biohemijskofizioloških osobina, što otežava njihovu identifikaciju. U cilju odabira testova pogodnih za brzu i pouzdanu identifikaciju P. s. pv. syringae, morsprunorum i persicae, primenjeni su standardni bakteriološki i molekularni testovi. Diferencijacija sojeva izvršena je LOPAT i GATTa testovima, posmatranjem razvoja u hranljivom rastvoru sa saharozom, sposobnošću sojeva da formiraju čestice leda, kao i mogućnošću korišćenja različitih ugljenikovih jedinjenja. PCR metod korišćen je u detekciji gena odgovornih za proizvodnju toksina siringomicina kod soja P. s. pv. syringae (syrB i syrD geni) i koronatina kod soja P. s. pv. morsprunorum rase 1 (cfl gen). Proizvodnja siringomicina potvrđena je i biotestom, korišćenjem gljiva Geotrichum candidum, Saccharomyces cerevisiae i Rhodotorula pilimanae kao indikatora. Proverom patogenosti sojeva na plodovima limuna, nesazrelim plodovima nektarine i mahunama boranije, došlo je do ispoljavanja simptoma različitog intenziteta, na osnovu kojih se može izdvojiti pv. syringae od ostala dva patovara. Primenom Rep-PCR metode, uz korišćenje REP, ERIC i BOX prajmera, ustanovljene su razlike u genetskim profilima proučavanih P. syringae patogenih varijeteta

Uticaj etarskih ulja timijana, cimeta i karanfilića na porast micelije Colletotrichum acutatum

Effects of the volatile phase of thyme, cinnamon and clove essential oils on Colletotrichum acutatum were investigated. Mycelial disc was placed in the center of the Petri dish (V=66 ml) containing PDA. Different volumes of either non- or ethanol-diluted essential oils were placed on the inner side of the dish cover to obtain final concentrations of 153, 107, 76, 46, 15, 14, 12, 11, 7.6, 3.82, 1.53, 0.153 and 0.0153 μl/L of air. The dishes were sealed with Parafilm and incubated in up-side-down position. After 7 days of incubation, mycelial growth was recorded by measuring the colony diameter. If no mycelial growth was recorded, the disc was transferred to a new PDA plate in order to evaluate whether the activity was either fungistatic or fungicidal. Mean growth values were obtained and then converted to inhibition percentage of mycelial growth compared with the control treatment. All the tested essential oils inhibited mycelial growth of C. acutatum in the dose dependent manner. Mycelial growth was totally inhibited by thyme oil in the concentration of 76 μl/L of air. The same results were obtained by cinnamon and clove oil in the concentration of 107 μl/L of air. Thyme and cinnamon oil had fungicidal effect in concentrations of 107 and 153 μl/L respectively. The results obtained provide evidence on the antifungal in vitro effect of the tested essential oils as potential means for the control of C. acutatum.Proučavan je efekat isparljive faze etarskih ulja timijana, cimeta i karanfilića na prouzrokovača antraknoze jagode Colletotrichum acutatum u uslovima in vitro. Fragmenti micelije gljive, prečnika 1 cm, zasejani su na KDA podlogu u petri-kutije (V = 66 ml). Različite koncentracije etarskih ulja (153, 107, 76, 46, 15, 14, 12, 11, 7,6, 3,82, 1,53, 0,153 i 0,0153 μl/l vazduha) dobijene su nanošenjem određene količine ulja, koncentrovanih ili razblaženih u etanolu, na središnji deo unutrašnje strane poklopca. Petri-kutije su zatvorene parafilmom i postavljene u obrnuti položaj, a porast micelije je meren posle 7 dana inkubacije. U kulturama u kojima nije došlo do porasta micelije fungicidno ili fungitoksično dejstvo određeno je prebacivanjem fragmenata na KDA podloge bez prisustva ulja. Efekat etarskih ulja predstavljen je procentom inhibicije porasta micelije, poređenjem sa kontrolom. Proučavana etarska ulja timijana, cimeta i karanfilića su svojom gasovitom fazom inhibirala porast micelije C. acutatum. Stepen inhibicije zavisio je od primenjene koncentracije. Etarsko ulje timijana je potpuno inhibiralo porast micelije pri koncentraciji 76 μl/l vazduha, a cimeta i karanfilića pri koncentraciji 107 μl/l vazduha. Fungicidno dejstvo ispoljilo je etarsko ulje timijana u koncentraciji 107 μl/l vazduha i cimeta u koncentraciji 153 μl/l vazduha. Rezultati istraživanja in vitro pokazali su antifungalno dejstvo testiranih etarskih ulja, što govori o potencijalu korišćenja etarskih ulja u kontroli C. acutatum

Prouzrokovači bakteriozne uvelosti paradajza i žute uvelosti (Stolbur) paprike i paradajza

Bacterial diseases are very common in tomato and pepper crops, especially under favourable weather conditions. One of the economically most important pathogens that affect tomato production worldwide is Ralstonia solanacearum, causal agent of bacterial wilt of tomato. The pathogen survives in soil and water. It colonizes xylem, clogs the vascular tissue preventing water movement throughout the stem, causing colapse of the infected plants. In addition, wilting of tomato and pepper can be caused by Candidatus Phytoplasma solani (Stolbur Phytoplasma). Main sources of infection with this pathogen are wild plants from where it is further transmitted by feeding of leafhopper vectors. The aim of this paper is to point to distribution and economic importance of those diseases, as well as characteristics of the pathogens. Information about symptoms and epidemiology of the disease are important for an accurate disease diagnosis and pathogen identification, which contributes to the timely and successful protection strategy.Oboljenja bakteriozne prirode veoma su česta u usevima paradajza i paprike, posebno kada vremenski uslovi pogoduju nastanku i širenju infekcije. Među ekonomski najznačajnijim bakterijama koje ugrožavaju proizvodnju paradajza u svetu, izdvaja se prouzrokovač bakteriozne uvelosti paradajza Ralstonia solanacearum. Patogen se dugo održava u zemljištu i vodi. Naseljava ksilem biljaka onemogućavajući protok vode, usled čega dolazi do pojave uvelosti. Osim ovog patogena, simptome uvelosti paradajza i paprike može takođe prouzrokovati Candidatus Phytoplasma solani (Stolbur fitoplazma). Ovo oboljenje prenosi se cikadama, dok su glavni izvori infekcije korovske biljke. Cilj ovog rada je da se prikaže rasprostranjenost i ekonomski značaj navedenih oboljenja paradajza i paprike, kao i osnovne karakteristike njihovih prouzrokovača. Poznavanje simptomatologije i epidemiologije oboljenja je od posebnog značaja za pravilnu dijagnozu oboljenja i identifikaciju patogena, što doprinosi pravovremenoj i uspešnoj zaštiti