Baktericidno delovanje nekih Bacillus spp. i Trichoderma harzianum na fitopatogene bakterije

Biological control is an innovative, cost effective and eco-friendly approach for control of many plant diseases. Bacillus sp. and Trichoderma sp. were known for its mycoparasitic and antagonistic mechanism in the control of wide range of phytopathogenic diseases in many types of crops. This research is based on the antibacterial activities of some Bacillus spp. and Trichoderma harzianum in relation to the 10 selected phytopathogenic bacteria in vitro study. The results indicated that among 52 strains of Bacillus spp. presented against phytopathogenic bacteria, only 6 of them showed inhibition but only against Xanthomonas genera. Other Bacillus spp. strains weren't effective against tested phytopathogenic bacteria. Results of testing of T. harzianum efficacy against the growth of selected phytopathogenic bacteria showed that this fungi could be effective to strains from genera Pseudomonas and Xanthomonas but for other tested genera was ineffective. In further work, all of this trial need to be supported by evaluation of antimicrobial activity in vivo.Biološka kontrola predstavlja inovativni, isplativ, ekološki pristup za suzbijanje mnogih biljnih bolesti. Vrste roda Bacillus i Trichoderma su poznati po svom mikoparazitskom i antagonističkom mehanizmu suzbijanja širokog spektra fitopatogenih prouzrokovača bolesti kod brojnih poljoprivrednih kultura. U ovom radu proučavano je baktericidno delovanje nekih vrsta roda Bacillus, kao i gljive Trichoderma harzianum na 10 odabranih fitopatogenih bakterija u in vitro uslovima. Prema dobijenim rezultatima, od ukupno 52 testirana izolata iz roda Bacillus, samo 6 je inhibiralo porast fitopatogenih bakterija i to samo iz roda Xanthomonas. Rezultati ispitivanja efikasnosti gljive T. harzianum su ukazali na mogućnost delovanja ove gljive na bakterije iz roda Pseudomonas i Xanthomonas, ali ne i na druge rodove fitopatogenih bakterija testirane u ovom radu. Dalja istraživanja treba bazirati na proučavanjima antimikrobne aktivnosti testiranih agenasa prema fitopatogenim bakterijama u in vivo ogledima

Antagonističke interakcije rizobakterija i cistolikih nematoda krompira

The increased presence of pesticides in food chain and its consequences resulted in the development of biological agents as alternative methods of control invasive organisms. Rhizobacteria and nematodes are usual inhabitants of a soil biological network. Recent studies have shown that some rhizobacteria can act as nematode antagonists. The investigations were aimed to show a possible suppressive impact of some rhizobacteria - components of comercial microbiological manures on potato cyst nematode hatching in in vitro experiments. Effects of the three rhizobacterial species: Rhizobium leguminosarum bv. viciae, Rhizobium phaseoli and Bradyrhizobium japonicum (commercial products with sterile peat as medium) were observed on the hatching of G. rostochiensis. After 15 days of the beginning of the experiment, the percentage of hatched G. rostochiensis juveniles was counted. The hatching of juveniles in all rhizobacterial suspensions was reduced in comparison to control. The suspension of Bradyrhizobium japonicum caused greater inhibitory effect on the hatching of G. rostochiensis followed by Rhizobium leguminosarum. The impact of Rhizobium phaseoli on G. rostochiensis hatching was the least. In the similar experiment with G. pallida the supression of hatching was noticed as well. In our experiments, all the species of rhizobacteria used, decrease hatching of Globodera second stage juveniles. The antagonistic activity of these rhizobacteria on potato cyst nematodes as a potential tool for nematode biocontrol, requires further investigations.U cilju utvrđivanja antagonista krompirovih cistolikih nematoda, kao najznačajnijih parazita krompira, ispitivan je uticaj određenih rizobakterija koje predstavljaju komponente mikrobioloških đubriva na piljenje invazivnih larvi Globodera. Rezultati ogleda in vitro ukazuju na potencijalnu mogućnost korišćenja rizobakterija u biološkoj kontroli cistolikih nematoda krompira

Hlor-dioksid kao dezinficijens za kontrolu Ralstonia solanacearum u vodi, skladištu i opremi

Brown rot or bacterial wilt caused by bacterium Ralstonia solanacearum is the main limiting factor in potato production. Quarantine measures are necessary to avoid spread of disease to disease-free areas. R. solanacearum has been shown to contaminate watercourses from which crop irrigation is then prohibited causing further potential losses in yield and quality. The bacteria also spread via surfaces that diseased seed potatoes come into contact with. This study showed bactericidal activity of chlorine dioxide (CIO2) on R. solanacearum for disinfection of water, surface and equipment. The results showed that CIO2 solution at concentration of 2 ppm at 30 minutes of exposure time had bactericidal effect for disinfection of water. For surface and equipment disinfection, concentration of 50 ppm showed total efficacy at 30 min and 5 sec exposure time, respectively. Results suggest that use of CIO2 as a disinfectant has a potential for control of brown rot pathogen in water, storage and equipment.Mrka trulež ili bakteriozna uvelost krompira prozrokovana bakterijom Ralstonia solanacearum ograničavajući je faktor uspešne proizvodnje krompira. Sprovođenje karantinskih mera zaštite je neophodno kako bi se izbeglo širenje bakterije u regione u kojima bolest nije prisutna. S obzirom da R. solanacearum može kontaminirati vodene tokove i izvore koji služe za navodnjavanje useva, zabrana korišćenja dovodi do dodatnih potencijalnih gubitaka u prinosu i kvalitetu krompira. Bakterija takođe kontaminira površine sa kojima zaraženi semenski krompir dolazi u dodir. U ovom radu prikazana je baktericidna aktivnost hlor-dioksida (CIO2) na bakteriju R. solanacearum u cilju dezinfekcije vode, površine i opreme. Dobijeni rezultati pokazuju da CIO2 ispoljava baktericidni efekat za dezinfekciju vode u koncentraciji od 2 ppm nakon 30 minuta ekspozicije, za dezinfekciju površine u koncentraciji 50 ppm nakon 30 minuta ekspozicije i za dezinfekciju opreme u koncentraciji 50 ppm nakon 5 sekundi ekspozicije. Rezultati dobijeni u ovom radu ukazuju da CIO2 poseduje potencijal kao dezinficijens za kontrolu prouzrokovača mrke truleži krompira u vodi, skladištu i opremi

New Insight in the Occurrence of Early Blight Disease on Potato Reveals High Distribution of Alternaria solani and Alternaria protenta in Serbia

Early blight is an economically important disease of potato worldwide. Understanding which fungal pathogens are the causal agents of early blight and their distribution on the same host is essential to finding the best strategy for the control of this disease. Previous studies have shown that Alternaria solani is the main early blight pathogen parasitizing potato. Here, we analyzed genetic and phenotypic diversity in isolates of Alternaria spp. covering all potato production areas in Serbia. We showed that the four species of Alternaria were found in areas with different distributions of the species. The occurrence of Alternaria spp. was studied by analyzing isolates from symptomatic potato leaves during multiyear sampling. In addition to Alternaria solani, we detected three more large-spored species identified as A. linariae (syn. A. tomatophila), A. protenta, and A. grandis that were involved in early blight disease on naturally infected potato leaves in Serbia. Differentiation of species was supported by phylogeny obtained from the DNA sequences of the GAPDH, calmodulin and Rpb2 genes. Our findings present a new perspective into the population structure of large-spored Alternaria species associated with early blight disease. Within the groups of large-spored Alternaria present in Serbia, evidence of A. protenta at high frequency reveals new insight into the contribution of Alternaria species in early blight disease. This work opens new perspectives for early blight management, while the distribution of different species on the same host suggests that the etiology of disease could depend on crop organization and the presence of other Alternaria hosts in close proximity to potato plants

Occurrence and characterization of Alternaria species associated with leaf spot disease in rapeseed in Serbia

The global demand for rapeseed makes it one of the fastest growing markets in crop production, with a need for increasing growing area and productivity, both of which depend on effective pathogen control strategies. Alternaria pathogens cause serious losses of brassica crops and occur in most rapeseed-growing regions around the world. In this study, morphological, molecular, and pathogenic analyses of 113 isolates collected from nine important rapeseed-growing areas in Serbia identified four pathogens: Alternaria brassicae, A. brassicicola, A. japonica, and A. alternata, causing leaf spot disease. Molecular analyses of ITS, GAPDH, Alt a1, and ATP sequences revealed one multilocus haplotype for A. brassicae and A. japonica isolates, whereas for A. brassicicola and A. alternata three and five haplotypes were distinguished, respectively. Pathogenicity tests showed that A. brassicicola was the most virulent while A. brassicae and A. japonica exhibited the same level of pathogenicity. The A. alternata population was generally weakly pathogenic with one nonpathogenic, genetically separated but closely related group of isolates, suggesting that pathogenicity is more unstable in this phylogenetic lineage. The data recorded on rate of growth and sporulation of isolates at 0, 5, 10, 15, 20, 25, 30, 35, and 40 °C revealed significant differences in evolutionary strategies among species, as A. alternata had the widest optimum range and the fastest growth rate, A. brassicicola showed the highest sporulation intensity, and A. brassicae expressed lower optimum temperatures for sporulation compared to other groups. All species indicated the potential for cross-infection of cabbage, and some haplotypes of A. brassicicola were previously isolated from horseradish in Serbia, suggesting the presence of one persistent Alternaria population on multiple brassica hosts in the region. This report describes the first detailed study of Alternaria spp. in rapeseed in Serbia

Sličnosti i razlike u molekularnom paternu ITS regiona nekih Globodera rostochiensis populacija

Evolutionary relationships of organisms in the past are based on morphological, biogeographical, and paleontological data. The emergence of molecular tools has enabled the study of the genetic structure of organisms and study of their phylogeny using protein or nucleotide sequences, which is especially important for organisms such as cyst nematodes that have no fossil records and are morphologically very similar. This paper presents molecular characterization of some G. rostochiensis populations in our region based on molecular pattern of ITS region. Molecular characterization of the studied populations showed similarities with the previously characterized populations but also some differences.Evolutivni odnosi organizama u prošlosti su zasnivani na morfološkim, biogeografskim i paleontološkim podacima. Pojava molekularnih alata omogućila je izučavanje genetičke strukture organizama i proučavanje njihove filogenije uz pomoć proteinskih ili nukleotidnih sekvenci, što je posebno značajno kod organizama kao što su cistolike nematode koje nemaju fosilnih ostataka a morfološki su veoma slične. U ovom radu je data molekularna karakterizacija nekih populacija G.rostochiensis sa naših prostora u molekularnom paternu ITS regiona. Molekularna karakterizacija ispitivanih populacija je pokazala sličnosti ispitivanih populacija sa već ranije okarakterisanim populacijama ali i neke razlike

Assessment indicators viability of potato seed-tubers cv. Kondor

In this paper the results of quality wheat and final products are shown that depends on genetics' composition of cultivar, ecologic condition, the way of growing and from the factors that result interpreting wheat in form the final product. Knowledge of chemical or biochemical composition of grain of wheat as relations some qualitative parameters successfully directed the processes and operations products from wheat-final products. For wheat determinating of particular importance are: carbo hydrate-starch, proteins (glutenins, gliadines, albumines and globulines) lipids and multyenzymes systems (the presence of more different enzymes group as amylase complex, proteinase and peptidase, lipase and lipooksi­genase and some oksidoreductase).Istraživanja pokazatelja (osobine) životne sposobnosti su vršena na semenskim krtolama krompira sorte Kondor. Obuhvaćen je semenski materijal dve generacije: original i prva semenska reprodukcija. Proizvodnja semenskog materijala izvršena je tokom dve godine (2000. i 2001.) na tri lokacije (Kotraža, Sjenica i Golija). Čuvanje semenskih krtola u hladnim uslovima trajalo je oko 100 dana. Zatim je semenski materijal izlagan termičkoj indukciji nakon čega su uklonjene apikalne klice sa krtola. Posle toga semenske krtole su izložene tamnoj i svetloj fazi ispitivanja uz odgovarajuće temperaturne režime. Na semenskim krtolama utvrđivane su i merene sledeće osobine: broj klica, debljina klica, dužina klica i broj listova po krtoli. Između kategorija su ispoljene jasne i velike razlike u pogledu vrednosti osobina semenskih krtola, kao i različita statistička značajnost faktora i interakcija za broj klica, debljinu klica i dužinu klica. Za osobinu broj listova po krtoli nema statističke značajnosti nijedan faktor ili interakcije kod obe kategorije u sva tri termina

Proučavanje raznovrsnosti bakterije Pseudomonas syringae poreklom sa različitih voćaka u Srbiji

Pseudomonas syringae is a widespread and economically important plant pathogen, one found on a number of hosts, including fruit trees, field crops, vegetables, and ornamental plants. This bacterium has been experimentally identified as a parasite of pear, apple, apricot, peach, cherry, sour cherry, plum, and raspberry. The present study was designed to establish differences between strains isolated from fruit trees in Serbia. The pathogenic and biochemical characteristics of isolates were studied. The BOX-PCR method was used to generate genomic fingerprints of Pseudomonas syringae isolates and to identify strains that were previously not distinguishable by other classification methods. Different Bacillus sp. strains were tested for in vitro inhibitory activity against Pseudononas syringae isolates. Bacillus sp. strains show inhibitory activity only against P. syringae isolates that originated from peach. The obtained results demonstrate that the population of the bacterium Pseudomonas syringae from the fruit trees in Serbia is very diverse.Pseudomonas syringae je široko rasprostranjena i ekonomski značajna fitopatogena bakterija, sa širokim krugom domaćina koji uključuje voćke, ratarske, povrtarske i ukrasne biljke. Pseudomonas syringae u Srbiji je eksperimentalno potvrđen kao parazit kruške, jabuke, kajsije, breskve, trešnje, višnje, šljive i maline. Cilj ove studije bio je da utvrdi postojanje eventualnih razlika između sojeva izolovanih sa različitih vrsta voćaka u Srbiji. Proučavane su patogene i biohemijske osobine sojeva. BOX-PCR je korišćen za dobijanje profila izolata Pseudomonas syringae u cilju identifikacije sojeva koji se ne mogu utvrditi drugim metodama. Različiti sojevi roda Bacillus su testirani u cilju utvrđivanja njihove in vitro inhibitorne aktivnosti. Sojevi roda Bacillus su pokazali inhibitornu aktivnost samo na P. syringae izolovanih sa breskve. Dobijeni rezultati pokazali suda je populacija bakterije Pseudomonas syringae poreklom sa voća u Srbiji vrlo raznovrsna

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