RIPEST - Repository of the Institute of Pesticides and Environmental Protection
Not a member yet
1022 research outputs found
Sort by
Morfološke, odgajivačke i ekološke karakteristike izolata Monilinia spp., patogena koštičavog voća
No full textTri vrste roda Monilinia: Monilinia /axa, M. fructicola i M. fructigena rasirene su u zasadima kosticavih
vocaka na teritoriji nase zemlje. Javljaju se skoro svake godine prouzrokujuci velike gubitke. Navedene
vrste imaju potpuno isti krug domacina i izazivaju identicne simptome na svim domaCinima. Zato j e za
preciznu dijagnozu oboljenja i identifikaciju patogena do nivoa vrste neophodna izolacija i proucavanje
niza morfoloskih, ekoloskih i molekuarnih karakteristika dobijenih izolata. Za pouzdanu i brzu detekciju
patogena u biljnom materijalu preporucuju se i neke od metoda molekularne biologije. Medutim, one
cesto nisu dostupne za rutinske analize. S obzirom na to, cilj ovog rada bio je da se na osnovu uporednog
proucavanja izolata sve tri vrste roda Monilinia utvrdi da Ii postoji neka specifiena karakteristika koja
omogucava njihovo pouzdano razdvajanje. lstrazivanje je obuhvatilo proucavanje morfoloskih (boja
kolonije, odlike ruba i oblik kolonije, sporulacija, prisustvo koncentrienog prstena spora, kvalitativna
brzina porasta i prisustvo crne marginalne linije), odgajivackih (uticaj pet razliCitih hranljivih podloga i
uticaj 12 vrednosti kiselosti PDA podloge) i ekoloskih (uticaj temperatura i osvetljenje) osobina izolata.
lzolati vrste M. laxa formirali su na PDA podlozi koloniju svetlo smede do sive boje oblika rozete,
refojevitih ivica, bez prisustva spora. lzolati M. fructigena obrazovali su koloniju krem-fote boje, ravnih
ivica, sa prisutnim retkim sporama, dok su izolati M. fructicola imali smedu do sivu koloniju ravnih ivica
koja obilno sporulise i formira koncentricne prstenove spora. Utvrdeno je da su izolati M. laxa i M.
fructigena prosecno najbrze rasli na malt podlozi, dokje za vrstu M. fructicola optimalan porast zabelefon
na PDA podlozi. Generalno najveci porast zabelezen je na malt i PDA podlozi, dok je najmanji
bio na vodenom agaru. lspitivani izolati ispoljili su statisticki znacajnu razliku u brzini porasta micelije
na podlogama kiselosti u intervalu pH 3-9. Na jako kiseloj podlozi (pH 2) porast su ispoljili izolati M.
laxa i M. fructico/a, a na podlogama kiselosti vefoj od pH 9 porast je zabelezen samo za izolat M. fructigena.
Najveci broj ispitivanih izolata optimalan porast ispoljio je na temperaturama od 23 do 28°C,
dok su granicne temperature porasta bile u intervalima od 2-4°( minimum i od 31-34°( maksimum
u zavisnosti od vrste. Proucavani izolati rasli su razlicitom brzinom u razlicitim uslovima osvetljenja: izolati vrsta M. /axa i M. fructigena najbrzi prosecni porast imali su u mraku, dok je izolat M. fructicola
imao brzi prosecan porast u svetlosnom rezimu 12 h svetlost/12 h mrak.
Rezultati su pokazali da su vrste roda Moni/inia veoma varijabilne, da je precizna i pouzdana
identifikacija moguca jedino sveobuhvatnim posmatranjem morfoloskih, odgajivackih i ekoloskih
karakteristika, kao i da je pozeljna potvrda rezultata molekularnim metodama
Effect of entomopathogenic nematodes on three soft scale insect species (Hemiptera: Coccidae)
No full textVirulence and pathogenicity of commercial strains of entomopathogenic nematode species
Steinernema carpocopsoe, S. feltiae and Heterorhobditis bacteriophora were tested on young
females of Pulvinorio hidrongeoe, Portenoleconium corni and Co~cus pseudomagnoliorum. All
three scale insect species are polyphagous, with variety of ornamental plants as their hosts. The
latter two can be serious pests in orchards, especially in organic ones. C. pseudomognoliorum
is known as pest of citrus and P. corni of various continental fruit tree species in Serbia. The
laboratory tests were carried out in plastic Petri dishes with infective juveniles applied on filter paper.
Treatments with different nematode concentrations and control were replicated five times with 10
insects in each Petri dich. After 7 days all insects were dissected. Only dead insects with presence
of nematodes and/or clear symptoms of infestation were considered killed by nematodes. Results
showed that all scale insects are hosts for all tested nematode species, since second generation of
infective juveniles was observed in each case. Highest insect mortality was observed within highest
concentration (50 infective juveniles per insect) in all combinations. Partenoleconium corni had the
greatest overall nematode presence (90-1 00%) with H. bacteriophora causing 100% mortality of
young females. Pulvinaria hidrongeae mortality was overall 80%, while highest mortality was 92%
with $. carpocapsae. The least effect nematodes had on C. pseudomagnoliorum causing overall
mortality of about 70%, which is probably due to high mortality rate in first days of experiment,
as in control of 32%. Our results show that entomopathogenic nematodes caused high mortality
rate of examined species. Further work is needed for developing strategies for field application.
Potential inclusion of entomopathogenic nematodes in strategies for scale insects control could be
of great importance, especially in organic orchards and urban areas
Organophosphorus pesticides in agricultural products and potential ways for reduction of their levels relating to improvement of people’s health
No full textOrganophosphorus pesticides (OPPs) are some of the most widely used pesticides in the world. Although the first OPPs were synthesized in the 19th century, their usage increased rapidly in the 1970s, when organochlorine pesticides, such as DDT, were prohibited due to their long-life persistence in the environment. Practically from that time until today, OPPs are irreplaceable chemicals for harmful insects’ control, as well as for suppression of the certain weed species and some plant pathogens (diseases). Therefore, those pesticides are normally used in agriculture and veterinary practices, as well as in homes and gardens. Generally, OPPs are regarded as safe for crops and animals due to their relatively fast degradation rates. However, these compounds are highly toxic, and their indiscriminate and intensive use may cause residues in food and the environment. When such agrochemicals are used according to good agricultural practices, the established maximum residual limits (MRLs) cannot be exceeded, while their incorrect application in terms of dosage, frequency of application, respect of the prescribed withdrawal period, etc. may produce higher amounts of residues than allowed considering human health and potential environmental contamination. Numerous reports of an extremely high incidence of poisoning by OPPs, sometimes with fatal outcome, point out the severity of this problem. Considering this context, a necessity is evident for continuous monitoring of OPPs residues in samples of different origins. Data obtained in systematic environmental monitoring would not only provide the statistics, but also a basis for adopting more stringent legal regulations, which would further reduce unprofessional and unscrupulous uses of these compounds. Additionally, although the MRLs are a credible and useful means for regulating acceptable pesticide uses, they are not sufficient for assessing human health hazard from residue intake unless accurate knowledge about residue loss in processing treatment is available. Various food processing techniques, practiced at the industrial as well as household level, have been found to significantly reduce pesticide residues in most foodstuffs. Current interest in obtaining more information about pesticide residue levels in “processed food” from “primary food commodity” is increasing significantly. This chapter summarizes the results of monitoring agricultural products for the presence of organophosphorus pesticides, putting a special emphasis on potential ways for reduction of their levels
First Report of 'Candidatus phytoplasma solani' in Sunflower in Bulgaria
No full textThe molecular identification of phytoplasma from infected sunflower in Bulgaria is reported. During a survey in the Boliarsko area in the Yambol region of Bulgaria, phytoplasma-like symptoms were observed on sunflower. The observed symptoms included yellowing, deformations and proliferation of flowers and sterile (empty) seeds. The Polymerase Chain Reaction (PCR) analyses with primers specific for the 16S ribosomal gene of phytoplasmas confirmed that symptomatic samples of sunflower were infected by phytoplasmas. Phytoplasmas were identified using sequence analyses of PCR amplified 16S rDNA. The obtained sequence showed identity with the 'Candidatus Phytoplasma solani' strain from corn from Bulgaria and other 39 strains deposited in the GenBank. To our knowledge this is the first report of stolbur phytoplasma in sunflower (Helianthus annuus) in Bulgaria, adding a new cultivated plant-species to the already wide natural host range of stolbur phytoplasma.4th European Bois Noir Worksho
Uticaj temperature vazduha na dinamiku brojnosti biljnih vašiju (Hemiptera: Aphididae) u lucerištu
No full textTemperatura vazduha i padavine, kao najvažniji pokazatelji klime, utiču na stanje useva, ali i na
brojnost štetočina. Prvi put kod nas ispitivan je uticaj temperature vazduha na brojnost biljnih vašiju
lucerke: Therioaphis trifolii i Acyrthosiphon pisum.
Dinamika brojnosti biljnih vašiju na lucerki je praćena na svakih 10 dana na dva lokaliteta (Ovča
i Progar) tokom trogodišnjih istraživanja (2011-2013). Da bi se pronašla zavisnost između brojnosti
biljnih vašiju i temperaturnih uslova povoljnih za njihov razvoj, izračunate su korelacije između temperature
vazduha i broja vašiju. Testirane su korelacije između brojnosti biljnih vašiju i suma njihovih
optimalnih temperatura, kao i korelacije između brojnosti vašiju i suma srednjih dnevnih, maksimalnih
i minimalnih dnevnih temperatura. Koeficijent korelacije (Ck) je izračunat u programu Fortran na
osnovu samostalno razvijenih formula. Vrednosti temperatura vazduha na ispitivanim lokalitetima
su dobijene iz baza Republičkog hidrometeorološkog zavoda.
Utvrđeno je da postoji korelacija između temperature vazduha i brojnosti vašiju T. trifolii i A. pisum
na lucerki. Therioaphis trifolii je bila najbrojnija vaš na lucerištima u Srbiji u istraživanom periodu. Visoke
temperature, oko 35ºC, pogoduju njenom razviću, zbog čega se naziva i „vaš tople sezone”. Vrsta T.
trifolii se u istraživanjima u velikoj brojnosti javila tokom dužeg dela vegetacije lucerke, naročito u
letnjem periodu. Njena pojava je najbolje korelisana sa sumom maksimalnih dnevnih temperatura
(Ck=0,595) i sa sumom srednjih dnevnih temperatura u opsegu 20-30°C (Ck=0,546) pet dana pre pojave
velike brojnosti. U toku leta kada su temperature izuzetno visoke u trajanju od bar 5 dana, stvaraju se
povoljniji uslovi za pojavu veće brojnosti ove vaši.
Vrsta A. pisum je pre dve decenije bila najbrojnija vaš na lucerištima u Srbiji. U ovim istraživanjima
nađena je u manjoj brojnosti od T. trifolii. Najveću brojnost postiže sredinom maja, dok je u najtoplijem
delu godine prisutna u minimalnoj brojnosti. Pojava A. pisum je najbolje korelisana sa sumama srednjih
dnevnih temperatura u opsegu 15-25ºC (Ck=0,569) i sa sumama maksimalnih dnevnih temperatura
(Ck=0,542), 30 dana pre njihovog pojavljivanja u visokoj brojnosti. Da bi vrsta A. pisum postigla veću
brojnosti u lucerištu neophodno je da optimalni temperaturni uslovi budu ispunjeni mesec dana pre
toga.
Dobijeni rezultati pokazuju da su klimatske promene jedan od razloga neočekivanog porasta
brojnosti T. trifolii poslednjih godina u odnosu na njenu brojnost ranije. Značaj prikazanih rezultata
se ogleda u dobijanju, po prvi put na našim prostorima, korelacije između klimatskih faktora (temperature
vazduha) i brojnosti ispitivanih vašiju
Effects of antagonostic bacteria on Monilinia fructicola
No full textMicroorganisms account for most of the diversity of life on our planet. There are more
kinds of microbes than plants, vertebrates, and insects combined. The dominating
groups of microorganisms are bacteria, actinomycetes, fungi, soil nematodes and
protozoans. It is estimated that less than one percent of all microbial species have been
identified. Researchers believe that the study of microbes will reveal novel biochemicals
useful to humans as medicines, biopesticides, biofuels, etc. Biopesticides based on
microorganisms may represent a desirable path in crop protection because they do not
exibit adverse effect on the environment. Recently, we conducted screening of many
bacterial isolates originating from different substrats for their antifungal properties.
Afterwords, we developed two different types of biopesticide formulations (two
suspension concentrates /SC/ and one suspo-emulsion /SE/) starting from two promising
antagonistic strains of Bacillus subtilis and tested their bioactivity on apple fruits. The
experiment on wound-inoculated apple fruits showed that the SE formulation was as
effective as a reference synthetic fungicide and that its effectiveness remained stable for
at least 24 hours. The aim of this study was to determine if isolated bacterial strains
could be used in cherry protection from brown fruit rot pathogen. In vitro antagonistic
activity assays were performed in 90mm Petri plates using wells technique, while in vivo
study was conducted on mature wounded cherry fruits. The results showed that
investigated bacteria exhibited similar antifungal properties against Monilinia fructicola
in vitro as it was observed against apple fruit pathogens, and that the same strains of 8.
subtilis should be selected as the best for further testing in vivo. On inoculated cherry
fruits, SC formulation was the most effective, 59.6% compared to the control
Antifungal activity of essential oils against Monilinia spp.
No full textMonilinia spp. are plant pathogens that cause brown rot of fruit, one of the most important fungal
diseases of cherries worldwide. The disease is controled by preharvest fungicide application,
while in most European countries, postharvest application offungicides is not allowed. To reduce
the amount of synthetic pesticides in the environment and their residues in food products, ecofriendly
alternatives to synthetic pesticides, such as natural substances, became an object
of many studies. Essential oils from aromatic and medicinal plants have shown antifungal
properties and therefore may play a role in the control of many plant diseases. Therefore, the
aim of this study was to investigate the potential of numerous essential oils to be used against
Monilinia spp. Cultures of M. laxa, M. fructigena and M. fructicola were exposed to volatile
phase of over 50 oils for seven days. Minimum fungistatic and lethal concentrations, as well
as minimum exposure duration to achieve the lethal effect, were determined. The growth rate
of the tested microorganisms was partially or completely inhibited by the studied oils applied at
concentrations of 0.04-0.65 μI/ml air. After seven-day exposure to the concentration of 0.04 μII
ml air only seven oils (five different oregano oils, thyme and lemon grass oils) were lethal to all
investigated species. However, after one-day exposure, the same oils showed the lethal effect at
0.08 μI/ml air. These results indicate that some of the tested essential oils could be used for the
control of Monilinia spp
Prevalence of stolbur phytoplasma in leafhoppers and planthoppers collected in vineyard, corn and potato fields and their surroundings in Switzerland
No full textEfikasnost različitih kombinacija fungicida u suzbijanju prouzrokovača mrežaste pegavosti ječma
No full textSeven fungicide mixtures (epoxiconazol + metconazole, boscalid + epoxiconazole, pyraclostrobin + epoxiconazole, prothioconazole + tebuconazole, picoxistrobin + cyproconazole, azoxystrobin + cyproconazole and spiroxamine + tebuconazole + triadimenol) were evaluated for control of net blotch of barley caused by Drechslera teres, as well as yield losses, over the 2010 and 2011 growing seasons. Two applications of the fungicide combination pyraclostrobin + epoxiconazole at the rate of 1.0 l ha-1 were the most effective treatment in controlling the disease and improving yield in both experimental years. Treatments with the fungicide mixtures epoxiconazol + metconazole and spiroxamine + tebuconazole + triadimenol showed the least effectiveness in disease control, as well as yield increase.Ispitivana je efikasnost sedam različitih kombinacija fungicida (epoksikonazol + metkonazol, boskalid + epoksikonazol, piraklostrobin + epoksikonazol, protiokonazol + tebukonazol, pikoksistrobin + ciprokonazol, azoksistrobin + ciprokonazol i spiroksamin + tebukonazol + triadimenol) u suzbijanju prouzrokovača mrežaste pegavosti ječma Drechslera teres, kao i njihov uticaj na prinos tokom 2010. i 2011. godine. Najveću efikasnost u obe ispitivane godine ispoljila su dva tretmana kombinacijom fungicida piraklostrobin + epoksikonazol primenjenom u količini 1.0 l ha-1. Kombinacije fungicida epoksikonazol + metkonazol i spiroksamin + tebukonazol + triadimenol su pokazale najslabije delovanje na prouzrokovača mrežaste pegavosti ječma, kao i najmanje povećanje prinosa u poređenju sa kontrolom
Monitoring bakterioza šampinjona u Srbiji
No full textMonitoring of button mushroom bacterial diseases was conducted to estimate the presence and identity of mycopathogenic bacteria and to determine the predominant bacterial pathogen in Serbia. Samples were collected from mushroom farms during 2006-2010 and also from fresh markets during 2014-2015. The collected samples showed either symptoms of brown blotch or different degrees of brown discoloration on caps and stalks of Agaricus bisporus resembling bacterial infection. The presence of bacterial droplets on gills was not recorded. The isolated bacteria were Gram-negative and fluorescent on King’s medium B. In pathogenicity tests, most bacterial isolates induced superficial or sunken brown lesions with differences in the level of discoloration on A. bisporus tissue blocks after artificial inoculation. Based on LOPAT characteristics, the isolates were divided into two groups, showing characteristics of either the LOPAT group Va or group III. Based on these features and other differential biochemical characteristics, the presumptive Pseudomonas tolaasii isolates were confirmed by specific PCR. The other group of isolates was subjected to sequencing of the 16S rDNA. Based on these sequences most isolates were identified as Pseudomonas agarici, while two strains belonged to Pseudomonas fluorescens.
The survey resulted in detection and identification of P. tolaasii in 11 locations and P. agarici in 7 locations in Serbian mushroom farms. Most samples from fresh markets were infected with P. tolaasii, suggesting that this pathogen has been the predominant cause of bacterial diseases in Serbian mushroom-growing facilities over the past 10 years.Monitoring bakterioza šampinjona sproveden je s ciljem da se proceni prisustvo i identitet mikopatogenih bakterija i utvrdi dominantna bakterija na šampinjonima u Srbiji. Uzorci su prikupljeni iz gajilišta šampinjona u periodu 2006-2010. godine i sa zelenih pijaca tokom 2014-2015. godine. Na prikupljenim uzorcima registrovani su simptomi smeđe pegavosti i
promene boje tkiva različitog stepena na šeširima i drškama Agaricus bisporus koji su nalikovali
bakterijskoj infekciji. Prisustvo bakterijskog eksudata na listićima sporofora nije zabeleženo.
Izolati bakterija su bili gramnegativni i stvarali su fluorescentni pigment na King-ovoj podlozi
B. U testovima patogenosti, većina izolata izazivala je površinske ili udubljene braon lezije sa
različitim stepenom promene boje na isečcima tkiva A. bisporus nakon veštačke inokulacije.
Na osnovu LOPAT testova, izolati su podeljeni u dve grupe, jednu sa karakteristikama LOPAT
Va grupe i drugu sa karakteristikama LOPAT grupe III. Na osnovu ovih osobina i drugih diferencijalnih biohemijskih karakteriistika, identitet izolata za koje se pretpostavilo da pripadaju Pseudomonas tolaasii potvrđen je specifičnom PCR reakcijom. Kod druge grupe izolata sekvencioniran je 16S rDNK. Na osnovu ovih sekvenci većina izolata je identifikovana
kao Pseudomonas agarici, dok su dva soja pripadnici Pseudomonas fluorescens.
Kao rezultat istraživanja P. tolaasii detektovana je i identifikovana na 11 lokaliteta, a P. agarici
na sedam lokaliteta u gajilištima šampinjona u Srbiji. Većina uzoraka sa zelenih pijaca bili su
zaraženi bakterijom P. tolaasii, ukazujući na to da je ovaj patogen bio dominantan uzročnik
bakterioza na šampinjonima u gajilištima u Srbiji u prethodnih 10 godina