Spatial distribution of benzimidazole resistance of Cercospora beticola Sacc. in Serbia

In order to check distribution of resistance of C. beticola isolates to benzimidazole fungicides we collected samples from four distinct geographical districts with different fungicides history in Serbia. From all localities about 40 - 50 isolates of C. beticola were collected and subjected to testing sensitivity to benzimidazoles in the laboratory. Due to RG of isolates on the discriminatory concentrations of carbendazim and thiophanate methyl we concluded level of resistance to benzimidazoles. Discriminatory concentration for carbendazim was 1 mg/l while for thiophanate methyl was 5 mg/l. Very high frequency of resistance of C. beticola isolates to benzimidazole fungicides on locality West Bačka (98 %), Srem (100%) and Moravica (97%), while on locality Rasina decrease frequency of benzimidazole resistance with 18% was established. Frequency of resistance of C. beticola populations to benzimidazoles was stable on locality where benzimidazoles were applied in the past, while on locality where they have never been applied it varies

Morfološka i molekularna identifikacija Colletotrichum acutatum sa ploda paradajza

Colletotrichum gloeosporioides, Colletotrichum acutatum, Colletotrichum coccodes, and Colletotrichum dematium are the four main species of Colletotrichum that cause tomato anthracnose. In Serbia, the occurrence of anthracnose on tomato fruit has been recorded during the last several years. Typical fruit symptoms include dark, sunken, and circular lesion with orange conidial masses. Pathogen isolates were obtained from a diseased tomato fruits, on PDA medium forming a white to gray colonies. The cultures developed black acervuli around the center of the colony. Conidia were hyaline, aseptate, and fusiform or rarely cylindrical. Appressoria were smooth, simple, clavate to ovate, and varied from light to dark brown. Pathogenicity tests with representative isolates were conducted on symptomless, detached tomato fruits. All tested isolates caused anthracnose lesions on tomato fruit after 7 days of incubation. Koch's postulates were fulfilled by reisolation from inoculated tomato fruits. PCR analysis (using species-specific primer pair, CaInt2/ ITS4) of genomic DNA from tomato isolates resulted in an amplification product of 490 bp, specific for C. acutatum, further confirming the identity of the pathogen. Based on morphological and molecular characteristics, the isolates from tomato fruit were determined as C. acutatum.Četiri glavna prouzrokovača antraknoze paradajza iz roda Colletotrichum su: Colletotrichum gloeosporioides, Colletotrichum acutatum, Colletotrichum coccodes i Colletotrichum dematium. U Srbiji je tokom poslednjih godina zabeležena pojava antraknoze ploda paradajza. Tipični simptomi na plodu su tamne, ulegnute, kružne lezije sa masom narandžastih konidija. Sa obolelih plodova paradajza dobijeni su izolati patogena koji na KDA podlozi obrazuju bele do sivo obojene kolonije. Acervuli crne boje formiraju se u kulturi oko centra kolonije. Konidije su hialinske, neseptirane, fusiformne ili ređe cilindrične. Apresorije su glatke, jednostavne, okruglastog ili oblika izdužene palice, svetlo do tamno braon boje. Test patogenosti je obavljen sa reprezentativnim izolatima, na odabranim, zdravim plodovima. Svi ispitivani izolati prouzrokuju antraknozne lezije na plodu paradajza 7 dana nakon inokulacije. Kohovi postulati su zadovoljeni reizolacijama sa inokulisanih plodova paradajza. PCR analiza (korišćenjem para prajmera specifičinog za vrstu, CaInt2/ITS4) iz genoma DNA izolata sa paradajza rezultirala je amplifikacijom produkta od 490 bp, specifičnog za C. acutatum, što je potvrdilo identitet patogena. Na osnovu morfoloških i molekularnih karakteristika izolati sa ploda paradajza determinisani su kao C. acutatum

Prvi nalaz tumorogenih sojeva Agrobacterium radiobacter na malini u Srbiji

During the spring of 2003, gall symptoms on the roots and crowns of young raspberry plants cv. Vilamette were observed near Valjevo. Phytopathogenic bacteria were isolated from diseased plant samples. Based on the pathogenic, morphological, differential biochemical and physiological characteristics, the isolated strains were identified as tumorigenic Agrobacterium radiobacter (biovar 1 Agrobacterium). In order to confirm the identity of isolated strains by polymerase chain reaction (PCR) primers complementary to tms2 gene located on the Ti plasmid were used. In the first PCR protocol using a tms2F1 + tms2R2 primer pair, 617 bp products specific for tumorigenic Agrobacterium strains were amplified. The second PCR protocol, using a tms2F1 + tms2B primer pair, amplified the expected 458 bp products. On the basis of multiplex PCR with primers complementary to chromosomal gene coding for 23S rRNA, the isolated strains were classified as biovar 1 Agrobacterium (A. radiobacter). This is the first report of tumorigenic A. radiobacter on raspberry in Serbia.Tokom proleća 2003. godine, zapaženi su tumori na korenu i korenovom vratu mladih biljaka maline sorte Vilamette u okolini Valjeva. Iz obolelih uzoraka izolovane su fitopatogene bakterije. Proučavanjem patogenih, morfoloških i diferencijalnih biohemijsko-fizioloških karakteristika izolovanih sojeva, utvrđeno je da proučavani sojevi pripadaju bakteriji Agrobacterium radiobacter (biovar 1). U cilju potvrde identiteta izolovanih sojeva lančanom reakcijom polimeraze (PCR), korišćeni su prajmeri komplementarni tms2 genu lociranom na Ti plazmidu. U prvoj PCR reakciji izvedenoj korišćenjem tms2F1 + tms2R2 para prajmera, detektovani su fragmenti nukleinske kiseline veličine 617 baznih parova (bp), specifični za tumorogene sojeve A. tumefaciens. U drugoj PCR reakciji korišćenjem para prajmera tms2F1 i tms2B su amplifikovani PCR produkti očekivane veličine 458 bp, karakteristični za ovu bakteriju. Na osnovu multiplex PCR reakcije korišćenjem prajmera komplementarnih na hromozomalni gen koji kodira 23S rRNA sojevi izolovani iz tumora na korenu maline svrstani su u biovar 1 Agrobacterium (A. radiobacter). Ovo je prvi nalaz ove bakterije na malini u Srbiji

Morfološka i molekularna identifikacija izolata Alternaria alternata - patogena plodova kima u Srbiji

During 2013, samples of infected seed grown caraway were collected from commercially grown crops in the experimental field in Mošorin and analyzed for the presence of plant pathogenic fungi. In all samples of seeds, weaker germination and a high seed infection 100%, with phytopathogenic fungi of the genus Alternaria, was found. From the infected caraway seed, monosporial cultures, based on morphology, were identified as Alternaria alternata, and their pathogenicity proved on artificially inoculated caraway and parsley seedlings. Molecular identification was performed utilizing polimerase chain reaction (PCR) with primer pair ITS1/ITS4 and by amplification of the ITS region of ribosomal DNA. Gene sequences of selected isolates CC1 (KP822948), CC2 (KP822949) i CC3 (KP822950) exhibited 100% nucle­otide identity with the sequences of 31 isolates of A. alternata deposited in the GenBank. The presence of a large number of phytopathogenic fungi on caraway seed should be further investigated in order to clarify their relationships and relative significance.Tokom 2013. godine, na oglednom polju u Mošorinu, prikupljeni su uzorci zaraženog semena gajenog kima i analizirani na prisustvo fitopatogenih gljiva. U svim uzorcima semena, ustanovljena je slabija klijavost i visok stepen zaraze fitopatogenim gljivama iz roda Alternaria, 100%. Iz zaraženog semena izolovane su monosporijalne kulture, čija je patogenost potvrđena pojavom simptoma na veštački inokulisanim klijancima kima i peršuna, a na osnovu morfoloških svojstava identifikovane su kao Alternaria alternata. Molekularna identifikacija obavljena je primenom lančane reakcije polimeraze (PCR, Polymerase Chain Reaction) uz korišćenje prajmera ITS1/ITS4 i amplifikaciju ITS regiona ribozomalne DNK. Sekvence gena odabranih izolata CC1 (KP822948), CC2 (KP822949) i CC3 (KP822950) pokazale su 100% nukleotidne identičnosti sa sekvencama 31 izolata A. alternata deponovanih u GenBank bazi podataka. Prisustvo većeg broja vrsta gljiva na semenu kima, zahteva dalja ispitivanja njihovih međusobnih odnosa i relativnog značaja

Oplemenjivanje i proizvodnja pivskog ječma stvorenog u Institutu PKB Agroekonomik

Progress in selection and breeding of barley (for beer), depends of available genetic variabilitis, ways of implementing disirable gens in superior genotypes, as well as the selection (choice) efficiency of desirable genotypes, i. e. genetic lines. With high yield and good biological and non-biologic stress resistance, quality barley (for beer) needs to have low content of tailings and proteins, and high content of glucosan's. In last ten years breeding of barely (for beer) in Institute PKB Agroekonomik, recognized one sort of winter barley (for beer) - PKB PIVAN in 2007, whose more serious multiplication and commercial sale began in 2008.Napredak u selekciji i oplemenjivanju pivskog ječma zavisi od raspoložive genetičke varijabilnosti, načina ugradnje poželjnih gena u superiorne genotipove, kao i efikasnost selekcije (odabira) poželjnih genotipova odnosno linija. Pored visokog prinosa i dobre otpornosti na biološke i abiološke stresove, kvalitetan pivski ječam treba da ima i nizak sadržaj plevica i proteina, a visok sadržaj skroba. Za skoro 10 godina oplemenjivanja pivskog ječma u Institutu PKB Agroekonomik priznata je jedna sorta ozimog pivskog ječma (PKB Pivan) 2007. godine čije ozbiljnije semenarstvo i komercijalna prodaja semena započinje 2008. godine

Primena preparata Kerb za suzbijanje Viline kosice (Cuscuta sp.) u usevima šećerne repe

Šećerna repa je veoma osetljiva na prisustvo korova, posebno u ranijim fazama razvoja (8 nedelja od setve). Zbog sporog rasta karakteriše se slabom kompetitivnošću, što u uslovima jake zakorovljenosti može dovesti do potpunog propadanja useva. Brojne korovske vrste se ubrajaju u potencijalne uzročnike smanjenja prinosa ove ekonomski značajne kulture (Abutilon teophrasti, Sorghum halepense, Solanum nigrum, Chenopodium sp. i dr.) među kojima značajno mesto zauzima i Vilina kosica (Cuscuta sp.). Ova vrsta, uz prisustvo fitopatogene gljive Cercospora beticola, može dovesti do potpunog propadanja useva. Dvogodišnja istraživanja biološke efikasnosti preparate Kerb (propizamid 500 g/kg) u suzbijanju Cuscuta sp. su obavljena na imanju kompanije “Sunoko” tokom 2022. i 2023. god. Ispitivan je i nivo efikasnosti preparata u samostalnoj primeni i u kombinaciji sa drugim a.s.: fenmedifam+etofumesat, metamitron, klopiralid, trisulfuron-metil u različitim fazama razvoja šećerne repe. Ispitivani preparati su primenjeni tokom aprila meseca u razmaku od deset dana: Kerb samostalno (3 kg/ha, 0,7+1,5 kg/ha, 1,0+1,5 l/ha, 1,5+1,5 kg/ha, 0,7+0,7+0,7 kg/ha) i u kombinaciji: (A) 1,0+1,5 kg/ha Kerb +1,25 l/ha Betanal tandem (fenmedifam 200 g/l + etofumesat 190 g/l) + 1 l/ha Goltix gold (metamitron 700 g/l) + 30 g/ha Safari (triflusulfuronmetil 500 g/kg) + 0,1 l/ha okvađivač Magisi; (B) tretman I: 0,7 kg/ha Kerb + 1, 25 l/ha Betanal tandem + 1,5 l/ha Goltix gold + 30 g/ha Safari + 0,1 l/ha Magis; tretman II: 0,7 kg/ha Kerb+ 1,5 l/ha Betanal tandem + 1,5 l/ha Goltix gold + 30 g/ha Safari + 0,1 l/ha Magis; tretman III: 0,7 kg/ha Kerb + 2,0 l/ha Betanal tandem + 2 l/ha Goltix gold + 30 g/ha Safari + 0,1 l/ha Magis. Kao standardna tehnologija u suzbijanju Cuscuta sp. korišćen je preparat Conviso ONE (50 g/l foramsulfuron + 30 g/l tienkarbazon-metil) u količini primene 0,5+0,5l/ha uz dodatak 0,1% okvašivača Trend. Prva primena ispitivanih preparata je obavljena kada je šećerna repa bila u fazi 10 BBCH skale, a Cuscuta sp. (vidljivi žuti končići) se još nije vezala za mlade biljke šećerne repe. Na efikasnost ispitivanih preparata uticali su suvo (2022 god.) i kišovito (2023 god.) proleće. Tokom ocene efikasnosti (15 i 30 dana nakon primene) praćeni su simptomi fitotoksičnosti na listovima šećerne repe. Može se konstatovati da je najveća efikasnost (99%) postignuta nakon samostalne primene preparata Kerb u količini 1,0 + 1,5 kg/ha, a najmanja (30%) nakon jednokratne primene u količini 3 kg/ha. Fitotoksičnih promena na biljkama šećerne repe nije bilo osim prolaznog žutila (nakon jednokratne primene preparata Kerb). Na osnovu dobijenih rezultata može se konstatovati sledeće: samostalna primena preparata Kerb u količini 1,0+1,5kg/ha i kombinacija sa preparatima Betanal tandem, Goltix gold i Safari postiže sličan nivo efikasnosti u suzbijanju Cuscuta sp. kao standardna tehnologija Conviso ONE.https://enauka.gov.rs/handle/123456789/86912

Spatial distribution of benzimidazole resistance of Cercospora beticola Sacc. in Serbia

In order to check distribution of resistance of C. beticola isolates to benzimidazole fungicides we collected samples from four distinct geographical districts with different fungicides history in Serbia. From all localities about 40 - 50 isolates of C. beticola were collected and subjected to testing sensitivity to benzimidazoles in the laboratory. Due to RG of isolates on the discriminatory concentrations of carbendazim and thiophanate methyl we concluded level of resistance to benzimidazoles. Discriminatory concentration for carbendazim was 1 mg/l while for thiophanate methyl was 5 mg/l. Very high frequency of resistance of C. beticola isolates to benzimidazole fungicides on locality West Bačka (98 %), Srem (100%) and Moravica (97%), while on locality Rasina decrease frequency of benzimidazole resistance with 18% was established. Frequency of resistance of C. beticola populations to benzimidazoles was stable on locality where benzimidazoles were applied in the past, while on locality where they have never been applied it varies

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

Nematode pests of alfalfa and clover

Steam nematode (Ditylenchus dispaci ) is the most important nematode pest in lucerne and alfalfa in Serbia. Damage appears as paches of poorly growing, charateristically slunuded plants, with hypertrophied stems, leaves and buds. Heterodera medicaginis is not reported in Serbia. H. trifolli has been reported in Serbia, but we have not data about losses confed by this and another mentioned species.Lucerku i detelinu napada veći broj fitoparazitnih nematoda, od kojih su najznačajnije stabljikina nematoda (Ditylenchus dispaci ), cistolike nematode (Heterodera spp.). korenove nematode (meloidogyne spp.) i veći broj formi sa slobodnim načinom života. Radi sprečavanja njihovog širenja neophodno je sprovoditi antinematodne mere, posebno u odnosu na D. dispaci, pregledom uzoraka semena na kojem se nalaze klupčad ove vrste u stanju anabioze i tako prenose

Osetljivost izolata Cercospora beticola prema karbendazimu i flutriafolu u Srbiji

The sensitivity of 110 Cercospora beticola (Sacc.) isolates to carbendazime (benzimidazoles) and flutriafol (triazole DMI) was investigated. Isolates on PDA were obtained from diseased sugar leaves collected in 11 localities in Serbia during the August 2007. The medium effective concentration (EC50), the relative sensitivity (b) and the level of resistance (NR) in relation to the most sensitive isolate were calculated the method applied by Karaoglanidis et al. (2000). The obtained results confirmed already resistance of Serbian isolates of C. beticola to carbendazime, but for the first time isolates from Erdevik and Maradik showed a significantly decreased sensitivity to flutriafol.Ispitivana je osetljivost izolata Cercospora beticola (Sacc.), prouzrokovača pegavosti lišća šećerne repe iz 11 lokaliteta u Srbiji prema karbendazimu (grupa benzimidazola) i flutriafolu (grupa triazola DMI) tokom 2007. godine. Uzorkovanje je obavljeno tokom avgusta meseca. Za ispitivane izolate izračunate su srednje efektivne koncentracije (EC50), relativna osetljivost (b) i nivo rezistentnosti (NR) u odnosu na najosetljiviji izolat, po metodi Karaoglanidis i sar. (2000). Dobijeni rezultati su potvrdili već ranije dokazanu rezistetnost izolata C. beticola poreklom iz Srbije na karbendazim, ali po prvi put i značajno smanjenu osetljivost izolata poreklom iz Erdevika i Maradika prema flutriafolu