Susceptibility of pollen beetle (Meligethes aeneus F.) to insecticide with different mode of action and possibility of control

Repičin sjajnik (Meligethes aeneus F.) je najštetnija insekatska vrsta u usevima ozime uljane repice u svetu i kod nas. Najveće štete nanose imaga koji tokom ishrane oštećuju cvetne pupoljke u potpunosti izjedajući cvetne elemente. Monitoring populacija M. aeneus nа usevimа uljаne repice u Srbiji vršen je tokom trogodišnjih ogleda (2008-2010. godine) nа osnovu vremenа nаseljаvаnjа usevа uljаne repice i brojnosti imаgа u osetljivim fenofаzаmа rаzvojа usevа uljаne repice. U radu su primenjene metode sakupljanja pomoću žutih vodenih klopki i otresanja imaga sa vršnih cvasti uljane repice. Rezultati su pokazali da repičin sjajnik naseljava usev ozime uljane repice u fenofazi porasta stabla (BBCH 30-31), a da najveću brojnost ostvaruje u fenofazi zeleno-žutih pupoljaka (BBCH 57-59). U svim lokalitetima i godinama istraživanja brojnost imaga repičinog sjajnika prelazila je ekonomske pragove štetnosti. Najveća brojnost postignuta je u lokalitetu Kovin, zatim u lokalitetu Smederevo, a u lokalitetu Požarevac brojnost je bila najniža. Obzirom da gajenje uljane repice za sobom povlači i primenu insekticida za suzbijanje repičinog sjajnika, u radu je tokom trogodišnjih poljskih ogleda proučavana efikasnost insekticida rаzličitih mehаnizаmа delovаnjа: piretroidа (lаmbdа-cihаlotrin, аlfа-cipermetrin, bifentrin), orgаnofosfаtа (pirimifos-metil), kombinаcije orgаnofosfаtа i piretroidа (hlorpirifos + cipermetrin) i neonikotinoidа (tiаkloprid) na imaga M. aeneus. Komercijalne formulacije insekticida su primenjivаne u preporučenim dozаmа u usevima ozime uljаne repice u vreme vidljivih cvetnih pupoljaka, ali još zatvorenih (BBCH 55-57). Efikasnost piretroida i organofosfata je tokom svih ogleda bila od 90- 100%, a neonikotinoida od 85-95%, pa se zbog ispoljene visoke efikasnosti može preporučiti njihova primena u Srbiji. Osetljivost M. aeneus prema navedenim insekticidima je ispitana korišćenjem testa nanošenja insekticida na zidove posuda - Adult Vial Test i testa potapanja cvetnih pupoljaka uljane repice - Dipping test. U radu su osim preporučenih korišćene i smanjene doze insekticida (75, 50, 25, 10 i 5%). Dobijeni rezultati su pokazali da nije došlo do pojave rezistentnosti jer su imaga ispitivanih populacija M. aeneus ispoljila visoku osetljivost na sve ispitivane insekticide. Najveći mortalitet je beležen 24 sata posle tretmana. Prema kriterijumima za ocenu osetljivosti repičinog sjajnika na insekticide, testirane populacije se svrstavaju u drugu grupu tj. osetljive. Populacija iz lokaliteta Kovin se pokazala kao najmanje osetljiva. Određivanjem ukupnog sadržaja i koncentracija citohrom P450 monooksigenaza potvrđena je normalna osetljivost repičinog sjajnika na primenjivane insekticide.Pollen beetle (Meligetes aeneus F.) is the most damaging insect species in winter oilseed rape fields worldwide. The insect adults cause the greatest damage by feeding on the flower buds eating their parts entirely. M. aeneus population was monitored in the oilseed rape crops in Serbia during three year long period (2008 - 2010) by recording a moment of the crop infestation and number of adults in susceptible oilseed rape growth phases. During the experiments insects were collected by using yellow water traps and by shaking off the insects from the top flower clusters. The results showed that a pollen beetle inhabits an oilseed rape crop in the stem growth pheno-phase (BBCH 30-31) and reaches its population peak at the green-yellow bud phase (BBCH 57 – 59). In all the localities and the years of observation the population of pollen beetle adults exceeded the economic threshold. The highest population was recorded in the locality of Kovin, then Smederevo, and the lowest in Požarevac. Since a pollen beetle is usually controlled by application of insecticides, it was studied efficacy of some insecticides with different modes of action: pyrethroids (lambda-cyhalothrin, alpha-cypermethrin, bifenthrin), oganophosphate (pyrimifosmethyl), combination of oganophosphate and pyrethroid (chlorpyrifos + cypermethrin) and neonicotinoide (thiaclopride) on M. aeneus adults in three-year field experiments. The insecticides were applied according to the producer’s recommendation in the oilseed rape winter crops at the moment of visible but still closed flower buds (BBCH 55-57). In all the experiments efficacy of pyrethroids and organophosphates ranged from 90 to 100%, and neonicotinoide from 85 to 95%. Therefore, they can be recommended for use in a pollen beetle spraying program in Serbia. Susceptibility of M. aeneus to the insecticides was tested by the methods of insecticide deposition on test vial walls – Adult Vial Test, and by submerging oilseed rape flowers – Dipping test. Besides the recommended insecticide doses, it was tested several decreased rates (75, 50, 25, 10, 5%) of the recommended value. The obtained results showed no occurrence of the resistance since adults of the insect showed high susceptibility to all the insecticides tested. The highest mortality was recorded 24h after the treatments. According to criteria for evaluation of pollen beetle susceptibility to insecticides, the tested insect population belongs to the second group i.e. susceptible. Population from the Kovin locality was the least susceptible. By the determination of the total content and concentration of cytochrome P450 mono-oxygenase, it was confirmed normal susceptibility of pollen beetle to the insecticides

Effect of Market and User Characteristics on the Expected Quality of Taxi Service

The taxi system is one of the most famous and de-veloped subsystems of flexible passenger transport. To reach the goal of the system achieving maximum produc-tion efficiency, the management focus is directed at users and service quality (SQ). The SQ can have several forms: expected, targeted, delivered, and perceived SQ. We ex-amine the expected SQ, expressed through the users’ at-titudes about the importance of the defined parameters of the SQ, which represent the users’ expectations from the taxi system. The analysis included the data from the conducted studies in three selected taxi systems. The aim of this paper was to determine the effect of market and selected user characteristics on the user expectations, applying the Chi-Square Test. We conclude that the spe-cific market and certain user characteristics affect the user expectations of the taxi system. There is a moderate effect on the employed users, pensioners, and daily users of the taxi system. When it comes to the users who use the taxi system several times a month and week, there is a less significant effect. Other user categories have no sig-nificant correlation with the selection of the parameters of the SQ in the taxi system

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

Efikasnost različitih insekticida u poljskim uslovima u suzbijanju repičinog sjajnika (Meligethes aeneus F.) u usevima ozime uljane repice

Since pollen beetle, M. aeneus, is usually controlled by insecticides, the efficacy of several compounds with different modes of action against adult beetles was studied in a threeyear field study. The selected insecticides were: three pyrethroids (lambda-cyhalothrin, alpha-cypermethrin and bifenthrin), an oganophosphate (pirimiphos-methyl), a combination of an organophosphate and a pyrethroid (chlorpyrifos + cypermethrin) and a neonicotinoid (thiacloprid). The insecticides were applied at label rates to winter rapeseed crops at the moment of visible but still closed flower buds (BBCH 55-57). In all experiments, the efficacy of pyrethroids and the organophosphate ranged from 90-100%, while the efficacy of the neonicotinoid was 85-95%. Therefore, they can be recommended for control of pollen beetle in Serbia.S obzirom da gajenje uljane repice za sobom povlači i primenu insekticida za suzbijanje repičinog sjajnika kao najštetnije insekatske vrste, u radu je tokom trogodišnjih poljskih ogleda (2008-2010. godina) na tri lokaliteta (Kovin, Smederevo i Požarevac) ispitana efikasnost insekticida različitih mehanizama delovanja: piretroida (lambda-cihalotrin, alfa-cipermetrin, bifentrin), organofosfata (pirimifos-metil), kombinacije organofosfata i piretroida (hlorpirifos + cipermetrin) i neonikotinoida (tiakloprid) za imaga M. aeneus. Komercijalne formulacije insekticida su primenjivane u preporučenim dozama u usevima ozime uljane repice u vreme vidljivih cvetnih pupoljaka, ali još zatvorenih (BBCH 55-57). Efikasnost piretroida i organofosfata je tokom svih ogleda bila 90-100%, a neonikotinoida 85-95%, pa se zbog ispoljene visoke efikasnosti može preporučiti njihova primena u Srbiji

Etiology of bacterial diseases of young walnut trees in Serbia

In the summer and autumn of 2019-2020, young walnut orchards were monitored for the presence of bacterial diseases. Diseased walnut samples comprising trunks and branches with symptoms of vertical oozing canker (VOC), walnut bacterial blight (WBB) and superficial bark necrosis were collected from eight locations in Serbia. Based on phenotypic features, pathogenicity, and molecular assays using PCR with specific primers, 49 isolates obtained from samples showing VOC and WBB symptoms were identified as Xanthomonas arboricola pv. juglandis, while further two isolates obtained from bark necrosis were identified as Brenneria rubrifaciens. One tested X. a. pv. juglandis isolate obtained from a VOC sample produced deep cankers in the bark of inoculated trunks of young walnut trees (cultivars Chandler, Franquette and Šejnovo). Therefore, this is the first report of an association between X. a. pv. juglandis and VOC symptom in Serbia. Considering that X. a. pv. juglandis significantly endangers walnut production, the presence of this pathogen in walnut transplant imports needs to be assessed by an authorised laboratory. Furthermore, as this is also the first report of B. rubrifaciens on walnut trees in Serbia, it is noteworthy that this pathogen is not particularly harmful to young walnut trees

УТИЦАЈ Bacillus spp. НА ПАТОГЕНА ПШЕНИЦЕ Alternaria alternata И in vitro УСЛОВИМА

Species of the genus Alternaria are significant wheat contaminants during production, transport and storage, requiring biocontrol measures which typically rely on the bacteria from the Bacillus genera. As these are among the most beneficial and exploited biocontrol agents, in this study, the inhibitory activity of indigenous Bacillus spp. was assessed against the Alternaria alternata isolate originating from the wheat seed. Two of the fifteen Bacillus s pp. i ncluded i n t he s tudy s howed t he i nhibitory effect. Specifically, 25.0−55.0% inhibition of A. alternata growth was achieved when the isolate coded as NB11 was applied in 106−109 cells mL-1 concentrations. On the other hand, when applied in 107−109 cells mL-1 concentrations, the isolate coded as NB16 inhibited A. alternata growth by 35.2−51.1%, but was ineffective at lower concentrations. Thus, these in vitro assays indicate that both Bacillus spp. (NB11 and NB16) isolated from the wheat rhizosphere can be applied in practice in the control of A. alternata

Identifikacija rasa Pseudomonas savastanoi pv. phaseolicola na domaćim sortama pasulja

Halo blight caused by the phytopathogenic bacterium Pseudomonas savastanoi pv. phaseolicola is economically important disease of bean in our area. In the present study, the pathogen was isolated from the leaves of the diseased bean plants, with the leaf samples having been collected from cultivars Oplenac, Slavonski žutozeleni and Zlatko using a nutrient agar (NA) and the medium enriched with 5% sucrose (NSA). Pathogenicity of the obtained isolates was proved by inoculation of young bean pods and by hypersensitive reaction (HR) on tobacco and geranium leaves. Biochemical and physiological characteristics were tested by conventional phytobacteriological methods. The race identity of the isolates was determined using a differential set of Phaseolus spp.: Canadian Wonder, ZAA54 (A52), Tendergreen, Red Mexican U13, 1072 P. acutifolius, ZAA55 (A53), ZAA12 (A43) i Guatemala 196-B). Inoculation was performed with atomizer, by spraying of bacterial suspension onto the undersurface of primary leaves. Obtained results indicated that strains showed the most similarity to race 1 of this bacterium.Oreolna plamenjača pasulja čiji je prouzrokovač fitopatogena bakterija Pseudomonas savastanoi pv. phaseolicola ekonomski je štetno oboljenje ove gajene kulture kod nas. U ovom radu vršena je izolacija patogena iz obolelog lišća pasulja sorti Oplenac, Slavonski žutozeleni i Zlatko na hranljivi agar (NA) i podlogu obogaćenu saharozom (NSA). Patogenost izolata je dokazana infiltracijom bakterijske suspenzije u mlade mahune boranije i pozitivnom hipersenzitivnom reakcijom (HR) na listu duvana i muškatle. Biohemijsko-fiziološke odlike ispitane su standardnim bakteriološkim metodama. Pripadnost dobijenih izolata fiziološkim rasama određena je korišćenjem diferencijalnog sortimenta Phaseolus spp.: Canadian Wonder, ZAA54 (A52), Tendergreen, Red Mexican U13, 1072 P. acutifolius, ZAA55 (A53), ZAA12 (A43) i Guatemala 196-B. Inokulacija je vršena atomizerom, prskanjem naličja primarnog lišća bakterijskom suspenzijom. Dobijeni rezultati ukazuju na najveću sličnost izolata sa rasom 1 ove bakterije

Response of different beans against common bacterial blight disease caused by xanthomonas axonopodis pv. Phaseoli

Common bacterial blight (CBB) in beans, caused by the bacterium Xanthomonas axonopodis pv. phaseoli (Xap), is an economically important disease worldwide which reduces crop yields and seed quality. Since there is no satisfactory chemical control for the disease, the use of resistant cultivars is an important management strategy. Sources of immunity are not yet recognized, but tolerance has been reported in several genetic stocks. The main objective of this study was to determine resistance to CBB on twenty-two local and foreign beans grown in Serbia. Two inoculation methods with Xap (spraying and multiple needles) as well as naturally infected plants in field conditions were taken for evaluation. The experiments were conducted in randomized complete blocks with three replications. Reaction to Xap was assessed as a diseased leaf area and the disease severity index was calculated. The analysis of variance (ANOVA) for disease ratings of leaf reactions indicated significant interactions between cultivars and lines. Results indicate that none of evaluated beans was immune and was found to be resistant to CBB. HR 45, Oreol and XAN 159, -208, -273 were weakly susceptible; Biser, Dobrudzanski rani, KB 100, -101, Medijana, Naya Nayahit, Panonski gradistanac, Panonski tetovac, and Sremac were susceptible while Balkan, Belko, Dobrudzanski rani 7, Dvadesetica, Galeb, Maksa, Slavonski zutozeleni, and Zlatko were highly susceptible cultivars and lines. The five weakly susceptible can be identified and recommend as possible sources of tolerance in plant breeding program

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

An integrated SWOT–extended PIPRECIA model for identifying key determinants of tourism development: The case of Serbia

This paper proposes a new integrated model based on SWOT and extended PIvot Pairwise RElative Criteria Importance Assessment (PIPRECIA) that offers a systematic approach to strategic planning in tourism. The applicability of the proposed integrated model is demonstrated through a case study defining the main determinants of tourism development in Serbia. The result emphasizes the strategy Improving the organization, management, and enhancement of tourism development as the highest priority for implementation. The model facilitates decision-making in tourism, and its key advantages are its suitability for application in group decision-making and its simplicity