Slobodan B. Krnjajic

• PhD
• Principal Investigator at University of Belgrade

Background The increasing difficulties in combating anthelmintic resistance in gastrointestinal nematodes (GINs) of sheep worldwide, and the residues of chemical drugs in animal products and the environment, necessitate the search for alternatives. Previous studies have shown that plant essential oils (EOs) could be valuable anthelmintic agents, du...

Crop production in plastic greenhouses is one of the major sources of plastic pollution worldwide. The main hypothesis of this study is that the regular use of mulch film in greenhouses leads to the cumulative accumulation of microplastic particles (MPs) in the soil, which ultimately leads to changes in the soil properties. Therefore, the main obje...

Plastic pollution has become a major environmental problem, while the products of its degradation, microplastics (MPs), appear everywhere on Earth. Data on MPs in agricultural soils have appeared lately, but a significant knowledge gap exists regarding forest soils. In Serbia, municipal waste is often dumped in forests, creating environmental probl...

Colorado potato beetle (CPB) is an extraordinary example of pest resistance to insecticides. It is proved that increased activity of CPB’s ALiE / carboxylesterase is closely related to resistance to organophosphate insecticides. ALiE activity of different populations was tested, using spectrophotometry. The frequencies of ALiE activity of individua...

Background: The increasing difficulties in combating anthelmintic resistance in gastrointestinal nematodes (GINs) of sheep worldwide and the residues of chemical drugs in animal products and the environment necessitate the search for alternatives. Previous studies have shown that plant essential oils (EOs) could be valuable anthelmintic agents. The...

Background Gastrointestinal nematodes (GINs) represent major obstacle to modern small ruminant farming due to their various negative effects on animal health, welfare and productivity. The exclusive use of commercial, synthetic anthelmintics is no longer a sustainable option due to the development of resistance in GINs and the problem of residues o...

Nowadays, the exclusive use of commercial anthelmintics for the treatment of gastrointestinal nematode infections in ruminants is less sustainable due to anthelmintic resistance, as well as the problem of drug residues in animal products and the environment. Therefore, an integrated therapeutic approach is needed, including the search for alternati...

Gastrointestinal nematodes are very important parasites of domestic animals, especially in small ruminants. In sheep, diseases usually have a subclinical form with a decrease in body weight and production, and sometimes there can be visible clinical symptoms such as anorexia, anemia, severe diarrhea and protein loss, all of which together can lead...

Phytotherapy may be defined as the use of plants for the treatment of ailments and those represent a practice that dates since ancient times. It refers to the use of whole plants, their parts such as flowers, leaves, roots and seeds as well as substances extracted from them (plant extracts and essential oils) for treating various diseases. It also...

Simple Summary Inappropriate use of regular anthelmintic drugs has led to the development of anthelmintic resistance in sheep gastrointestinal nematodes (GINs) and consequently caused huge economic losses. Therefore, researchers worldwide are making efforts in finding novel strategies to control these parasites, which are mostly based on the ration...

In this work by encapsulation technique we have synthetized three new clove bud essential oil (CEO) Emulsifiable Concentrate (EC) formulations depending on the carrier (synthetic zeolite- F-CSZ, nature zeolite- F-CNZ and gelatin- F-CG). The main idea was to develop an eco-friendly biopesticide that can find use in plant protection as an alternative...

Herbal products such as essential oils may play a promising role in the treatment of infections caused by gastrointestinal nematodes (GINs). The aim of this study was to evaluate the in vitro potential of 11 essential oils (EOs) and one binary combination of isolated EO compounds, as well as the in vivo anthelmintic efficacy of two EO formulations....

The application of pesticides is an actual plant protection measure in agriculture that can have adverse effects on people's health and environments. A great attention is paid to the biological fungicides. Performed studies indicate satisfactory results of activities of essential oils, which furthermore point out to possibilities of their inclusion...

The development of resistance to commercial anthelmintics, particularly in different species of gastrointestinal nematodes (GINs), requires the search for alternatives. Within that context, the aim of this study was to evaluate the in vitro ovicidal activity of five different essential oils (EOs): Origanum vulgare, Satureja hortensis, Thymus vulgar...

Good environmental management needs evidence-based conservation measures, and those measures need both faunistical and ecological information. Following this path, for the first time in Serbia, a faunistical research of spiders at Subotica Sandland was organised in 2014 as a base for ecological arguments in landscape management of the area. The spi...

The economic losses caused by gastrointestinal nematodes of small ruminants are increasing today due to the development of anthelmintic resistance. Therefore, researchers from different parts of the world are searching for new, alternative strategies to control these parasites. As a valuable natural resource, medicinal plants and their products hav...

Essential oils (EOs) have historically been used for centuries in folk medicine, and nowadays they seem to be a promising control strategy against wide spectra of pathogens, diseases, and parasites. Studies on free-living nematodes are scarce. The free-living microbivorous nematode Panagrolaimus sp. was chosen as the test organism. The nematode pos...

The Colorado potato beetle, Leptinotarsa decemlineata (Say), is one of the most destructive pest species to have developed resistance to most chemical insecticides. We determined the composition and evaluated the potential of Tanacetum parthenium L. and Tanacetum vulgare L. (Asteraceae family) essential oil (EO) application as an alternative eco-fr...

Food production is challenged by different factors: climate changes, market competitiveness, food safety, public demands, environmental challenges, new and invasive pests, etc. Intensive food production must be protected against pests, which is nowadays impossible with traditional techniques. The use of eco-friendly biopesticides based on essential...

Flavescence dorée (FD) is a European quarantine grapevine disease transmitted by the Deltocephalinae leafhopper Scaphoideus titanus. Whereas this vector had been introduced from North America, the possible European origin of FD phytoplasma needed to be challenged and correlated with ecological and genetic drivers of FD emergence. For that purpose,...

The study reported the development of biodegradable, environment- and eco-friendly material based on natural polymers and lemongrass (Cymbopogon citratus L.) essential oil (LEO) for application as a green pesticide. The insecticidal effect of an emulsion composed of encapsulated LEO into a biopolymer matrix against the potato tuber moth (Phthorimae...

A survey of genetic diversity of “flavescence dorée” (FD)-related phytoplasmas in grapevines, alders and clematis as well as alder-feeding leafhoppers was conducted in France, Hungary, Germany, Italy and Serbia. Genotyping was based on the housekeeping gene map and on the vmp genes encoding surface variable membrane proteins. Transmission assays of...

Essential oils (EOs) from wild oregano, clove bud, rosemary, peppermint, basil and lemongrass were tested for their antibacterial properties against soft rot causing bacteria. The disc-diffusion method was used for the determination of theit inhibitory effects conducted in vitro. The results revealed that the tested EOs exhibited moderate to high a...

Numerous scientific research studies all over the world have addressed the problem of agriculture in the 21st century as being particularly sensitive to climate change, which has caused phytopathogenic bacteria to spread. Therefore, there is a clear and urgent need to contain this kind of risk in agricultural production (both conventional and organ...

The bean weevil (Acanthoscelides obtectus, Say) is a serious pest of stored bean seeds. Bean weevil control relies heavily on the use of synthetic insecticides. In the search for a sustainable alternative, the residual contact toxicity and anti-oviposition activity of thyme (Thymus vulgaris L.), rosemary (Rosmarinus officinalis L.) and basil (Ocimu...

Potato tuber moth (PTM), Phthorimaea operculella Zeller, represents a very dangerous potato pest in the warmer parts of the world. The harmfulness of the insect impact is reflected in the high level of tuber damage (up to the complete yield loss), as well as the complexity of its control. The damages caused by PTM to the potato production are consi...

The use of natural inert dusts against storage insect pests is increasing recently, as an alternative to conventional insecticides. Laboratory study was carried out to evaluate the contact effect of three inert dusts, diatomaceous earth (DE), kaoline (KA) and vermiculite (VE), at rates 5, 7.5, 10, 15 and 20 gm-2, against adults of Sitophilus oryzae...

The field pea is very important when it comes to the nutrition of domestic animals, due to a high content of proteins in its grains and aboveground biomass. The aim of this study was to examine genetic variability in quantitative traits of newly created field pea hybrids. The researchers studied two cultivars, one line and their F₃ and F...

A faunistic study of the family Elateridae was carried out in Bačka, the northwestern district of Vojvodina Province in Serbia, focusing on their preferred habitats and soil types. The survey included four locations with a total of 1059 ha, in which 35 species, belonging to 15 genera of Elateridae, were observed. The frequency of larval and adult f...

Unusual blight-like symptoms appeared on highbush blueberry plants in Serbia during August 2015 and infected plants showed browning and reddening of leaves, drying of foliage, and brown discoloration of internal vascular stem tissues. The objective of this study was to isolate and confirm a causal agent of the disease. Five diseased blueberry plant...

TOSCANO, B., P. STRBAC, Z. POPOVIC, M. KOSTIC, I. KOSTIC and S. KRNJAJIC, 2015. Faunistic inventory of click beetles in Srem region (Vojvodina Province, Serbia). Bulg. J. Agric. Sci., 21: 561–569 A survey was conducted on Elateridae fauna of Srem region, in the south of Vojvodina Province (Serbia) during 2010-2012. As many as 1202 specimens (666 ad...

A total of 23 viticultural regions in Serbia were surveyed from 2004 to 2006 to determine the occurrence and distribution of Scaphoideus titanus, vector of grapevine phytoplasma Flavescence dorée. Grapevine samples from over 600 plants showing suspected symptoms of phytoplasma infection, were collected from all surveyed regions for subsequent molec...

Sixteen samples of sorghum seed (Sorghum bicolor (L.) Moench.) 'Alba', 'Gold', 'Prima' and 'Reform' were analyzed in the localities of Bački Petrovac and Čantavir in the period 2009-2011. Tipresence of species belonging to the genera Epicoccum, Fusarium, Alternaria, Aspergillus and Penicillium was established in single and mixed infections. From th...

In August 2010 potato plants expressing symptoms of phytoplasma infection were collected from three localities in Vojvodina province of Serbia and analyzed for phytoplasma presence. Phytoplasma detection was performed by PCR/RFLP analyzes of 16S rRNA gene and by stolbur-specific PCR amplification with Stol11 primers. Stolbur phytoplasma was detecte...

During epidemiological survey for phytoplasmas in association with agricultural crops in Serbia, a new species of common weed has been detected to harbor phytoplasmas in Serbia. In 2010, a total of 38 samples of Picris hieracioides (Asteraceae), commonly known as hawkweed oxtongue, were sampled from vineyards in Jasenovik (near Niš, South Serbia) a...

The plant host range of a phytoplasma is strongly dependent on the host range of its insect vector. Maize redness in Serbia is caused by stolbur phytoplasma (subgroup 16SrXII-A) and is transmitted by the cixiid planthoper, Reptalus panzeri (Löw). R. panzeri was the only potential vector found to be infected with stolbur phytoplasm in and around mai...

The diversity of Auchenorrhyncha species was studied in vineyards affected by ‘bois noir’ (BN) and their surroundings in Serbia. Auchenorrhyncha specimens were collected for identification, statistic analysis and for stolbur phytoplasma presence detection. A total number of collected species was 49, belonging to 8 families. The most numerous was fa...

Elm yellows phytoplasmas (EY) belonging to the 16SrV-A subgroup were recently proposed as a new candidate species ‘Candidatus Phytoplasma ulmi’. These pathogens infect elm trees, causing leaf yellowing and premature drying. In this study, 25 isolates originating from localities in northeast, east and southwest Serbia were characterized by means of...

Tomato leaf miner Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), a devastating pest of tomato originating from South America has been recorded in Serbia on three localities: in tomato main greenhouse and open field production area located in the vicinity of town Leskovac (South Serbia), in surroundings of the village Donji Vrtogoš (near...

In a survey to determine the presence of Phytophthora ramorum in Serbia, ornamentals from garden centers, nurseries, and private and public gardens, as well as imported plant material, were inspected. In total, 577 plant, soil, and potting media samples were tested using various detection methods: lateral flow diagnostic test, enzyme-linked immunos...

SUMMARY Cicada Scaphoideus titanus Ball (Auchenorrhyncha: CicadeIidae) is a pest in Serbian vineyards. It is originates from North America and was introduced to Europe during the past century. In Serbia it was found in 2004. year. S. titanus is of great economic importance as the only known vector of the Grapevine golden yellowing phytoplasma Flave...

In August 2008, grapevine yellows (GY)-like symptoms were observed in vineyards near Podgorica, Montenegro. A survey of the grape growing area of Montenegro was conducted to identify and determine the distribution of phytoplasmas associated with grapevine. Phytoplasmas were detected in symptomatic vine plants using PCR with universal primers for am...

In a survey to determine the presence and distribution of Iris yellow spot virus (IYSV) in greenhouse ornamentals and onion field crops in 14 districts of Serbia as well as on imported ornamental plants, 1,574 samples were collected and analyzed by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). IYSV was not detected in near...

Maize redness (MR), induced by stolbur phytoplasma ('Candidatus Phytoplasma solani', subgroup 16SrXII-A), is characterized by midrib, leaf, and stalk reddening and abnormal ear development. MR has been reported from Serbia, Romania, and Bulgaria for 50 years, and recent epiphytotics reduced yields by 40 to 90% in South Banat District, Serbia. Poten...

In Europe Phytophthora ramorum has been reported on a range of ornamentals as well as on a limited number of tree species in at least in 11 countries: UK, Spain, Belgium, Germany, the Netherlands, Italy, France, Switzerland, Poland, Slovenia, France and Norway (http://rapra.csl.gov.uk). It is recorded mainly on Rhododendron but other hosts includin...

Elm yellows (EY) phytoplasma (‘Candidatus Phytoplasma ulmi’) is the causal agent of a decline in American elms in North America, and in Eurasian elm species and hybrids in Europe (Lee et al., 2004). EY is known to infect different Ulmus species: U. americana, U. minor, U. rubra, U. alata, U. serotina, U. crassifolia and U. chenmoui, showing differe...

Iris yellow spot virus (IYSV; genus Tospovirus, family Bunyaviridae) is established in several European countries (France, Italy, The Netherlands, Poland, Slovenia, Spain, and the UK) and its distribution in the EU region has increased since 2002 (3). In July 2007, symptoms resembling those of IYSV were observed in an onion (Allium cepa) seed crop...

Alder yellows (AldY) phytoplasma associated with common alder (Alnus glutinosa) and grey alder (A. incana) belongs to the 16SrV-C group and is closely related to the Flavescence dorée (FD) phytoplasma, a quarantine pathogen of economic importance that affects vineyards of southern Europe including Serbia. AldY phytoplasma has been reported in Franc...

A total of 23 viticultural regions in Serbia were surveyed from 2004 to 2006 to determine the occurrence and distribution of Scaphoideus titanus, vector of grapevine phytoplasma “flavescence dorée”. Grapevine samples from over 600 plants showing suspected symptoms of phytoplasma infection, were collected from all surveyed regions for subsequent mol...

Maize redness (MR) causes midrib, leaf and stalk reddening and abnormal ear development in maize in Serbia, Romania and Bulgaria. High populations of the ciixid Reptalus panzeri (Löw) were found in MR affected maize fields in the southern Banat region of Serbia in 2005 and 2006, and stolbur phytoplasma was detected in 20% of the insects. Stolbur ph...

Maize redness (MR), a disease causing midrib, leaf and stalk reddening and abnormal ear development in maize, has been reported from Serbia, Romania and Bulgaria for 50 years. Recent epiphytotics reduced yields by 40%-90% in southern Banat, Serbia. MR was recently associated with the presence of the stolbur phytoplasma, although the epidemiology of...

Studies of the efficacy of insecticides against pepper-Infesting aphids (Aphid/dae) D. Marcie, P. Kljajic, S. Krnjajic and I. Perie Pesticide and Environmental Research Centre, Banatska 31b, 11080 Zemun, Serbia and Montenegro Third Balkan Symposium on vegetables & potatoes, 6-10 September, Bursa, Turkey, 2004., Book of abstracts: pp 72. Green pe...

Biological efficacy of the most frequently used and some newly-introduced insecticides for controlling Colorado potato beetle (Leptinotarsa decemlineata Say) in Serbia was evaluated in Indjija (in 2000 and 2003), Zemun Polje (in 2002 and 2003) and Surcin (in 2002) localities, against 1st generation of CPB. Neonicotinoids (acetamiprid, imidacloprid...

In Yugoslavia over 3.000 ha of glasshouses and plastic greenhouses are used in vegetable production. In this production an important limiting factor is Trialeurodes vaporariorum W. The first attempts at biological control of T. vaporariorum were made in 1981 when Encarsia formosa Gahan was imported from the USSR. The relation between this wasp and...