Jaka Razinger

Agricultural institute of Slovenia - Kmetijski inštitut Slovenije · Plant Protection Department

A potential Delia radicum biological control strategy involving cauliflower plantlet inoculation with various fungi was investigated in a series of laboratory and glasshouse experiments. In addition to entomopathogenic fungi, fungi with a high rhizosphere competence and fungi with the ability to survive as saprotrophs in soil were tested. The follo...

The root aphid Tetraneura (Tetraneurella) nigriabdominalis (Sasaki), (Pemphiginae: Eriosomatini) was recorded on corn roots (Zea mays L.) in August 2011 in northeast Slovenia in the village Benica. The species was classified morphologically and by molecular methods.

The aim of the study was to assess entomopathogenic potential of 7 isolates from 6 entomopathogenic fungal species (EPF) isolated from various substrats in Slovenia against larvae of Agriotes sp. The fungal isolates tested were Beauveria bassiana, B. brongniartii, Metarhizium anisopliae (2 isolates), M. robertsii, Purpureocillium lilacinum and Clon...

In a model hyperaccumulation study a Cd/Zn hyperaccumulator Thlaspi caerulescens accession Ganges and a recently reported Cd/Zn hyperaccumulator Thlaspi praecox grown in increasing Cd and Zn concentrations in the substrate and in field collected polluted soil were compared. Plant biomass, concentrations of Cd and Zn, total chlorophylls and anthocya...

The mechanisms of plant defence against cadmium toxicity have been studied by short-term exposure of Lemna minor L. (common duckweed) to concentrations of CdCl2 ranging from 0 to 500microM. High accumulation of cadmium was observed (12,320+/-2155microgg(-1) at 500microM CdCl2), which caused a gradual decrease of plant growth, increased lipid peroxi...

An aegerolysin protein ostreolysin A6 (OlyA6) binds to cholesterol-complexed sphingomyelin and can be used for specific labelling of lipid rafts. In addition, OlyA6 interacts with even higher affinity with ceramide phosphoethanolamine (CPE), a sphingolipid that dominates in invertebrate cell membranes. In the presence of pleurotolysin B, a protein...

Čebulna muha (Delia antiqua [Meigen], Anthomyiidae) in porova zavrtalka (Phytomyza gymnostoma Loew, Agromyzidae) sta pomembna škodljivca čebule v Sloveniji. Predvsem poškodbe slednje zadnja leta pri nas opažamo vse pogosteje. Škodo povzročajo žerke, ki se zavrtajo v liste in izjedajo rove. Posledično se rastline zvijajo, zaostajajo v rasti in pride...

Marmorirana smrdljivka (Halyomorpha halys (Stål, 1855); [Hemiptera, Pentatomidae]) je predstavnik družine ščitastih stenic. Gre za invazivno polifagno vrsto, ki izvira iz Vzhodne Azije. Sredi 90-ih je bila vnesena v ZDA ter leta 2004 v Evropo. Danes je prisotna v večini evropskih držav. V zadnjih 15 letih so v gobah odkrili številne entomotoksične...

The objective of our research was to test hyperspectral imaging as a method for early detection and discrimination of biotic and abiotic stress in maize. We investigated the individual and combined effects of wireworm feeding and drought stress on leaf spectral responses and on various morphological and physiological traits of maize plants, selecti...

Entomopathogenic fungi (EPF) represent promising control agents against wireworms but success in field experiments is inconsistent. The physiological condition of the targeted insect is crucial for its ability to withstand fungal infection. In particular, nutritional status is among the most important determinants of the insects' immune defense. In...

We investigated the effect of soil inoculations (factor 1) of an entomopathogenic fungus Metarhizium brunneum 1868 and an aboveground pest (factor 2), the strawberry aphid, Chaetosiphon fragaefolii (Cockerell) (Hemiptera, Aphididae) on strawberry plants (e.g., plant physiology, hyperspectral analyses, yield…).

Plant diversity has the potential to conserve beneficials and thereby naturally controlling arthropod pests. Beneficials’ activity can be increased by pollen-rich plant species. Here we aimed to develop innovative viticultural systems that naturally control arthropod pests, by increasing plant diversity within vineyards planting of selected cover c...

p class="042abstractstekst">Scarab beetles (Coleoptera: Scarabaeidae) are a cosmopolitan group of beetles found on all continents except Antarctica. Because of their size, vibrant colors, and above all their role in the ecosystem, they are one of the most recognizable and studied taxons of beetles. Most larvae and adult beetles of species belonging...

The polyphagous brown marmorated stink bug (Halyomorpha halys Stål.) is an important pest in many countries. Recently it was noticed that it can feed on and cause damage to strawberries (Fragaria × ananassa Duch.). The metabolic response of strawberries to brown marmorated stink bug attacks was studied. Brown marmorated stink bugs attacked strawber...

Microbial inoculants can be an efficient tool to manage the soil and plant microbiomes providing direct beneficial effects, and for modulating native soil and plant-associated microbiota. However, the application of soil microbial inoculants as biofertilizers and biopesticides in agriculture is still limited by factors related to their formulation,...

Fungi are the most common pathogens of insects and thus important regulators of their populations. Lipid-binding aegerolysin proteins, which are commonly found in the fungal kingdom, may be involved in several biologically relevant processes including attack and defense against other organisms. Aegerolysins act alone or together with membrane-attac...

This paper investigates 71 isolates of two genera of entomopathogens, Metarhizium and Beauveria, and a biostimulative genus Trichoderma, for their ability to infect yellow mealworms (Tenebrio molitor) and to stimulate maize (Zea mays) growth. Fungal origin, host, and isolation methods were taken into account in virulence analysis as well. Isolates...

In recent decades, the spotted wing Drosophila (SWD) (Drosophila suzukii), an invasive pest, has caused a great deal of damage to fruit crops. There is therefore an urgent need to develop strategies to control the populations of this species. It has been found that the landscape context can buffer or increase the severity of pest outbreaks in agric...

p class="042abstractstekst">Plants respond to pest attack, among other mechanisms, by producing specific proteins with insecticidal properties. Proteins with toxic effects on insects have also been discovered in many other organisms, especially fungi and bacteria. Due to their biological function, insecticidal proteins represent an important potent...

Ostreolysin A6 (OlyA6) is a protein produced by the oyster mushroom (Pleurotus ostreatus). It binds to membrane sphingomyelin/cholesterol domains, and together with its protein partner, pleurotolysin B (PlyB), it forms 13-meric transmembrane pore complexes. Further, OlyA6 binds 1000 times more strongly to the insect-specific membrane sphingolipid,...

(1) Background. An extensive survey of grapevine-sown cover crops and spontaneous weed flora was conducted from 2019 to 2020 in organic vineyards in six European countries (France, Italy, Romania, Slovenia, Spain, Switzerland). Our main objective was to detect and identify the presence of Cylindrocarpon-like asexual morphs species associated with b...

We compared the changes of selected immune parameters of Porcellio scaber to different stressors. The animals were either fed for two weeks with Au nanoparticles (NPs), CeO2 NPs, or Au ions or body-injected with Au NPs, CeO2 NPs, or lipopolysaccharide endotoxin. Contrary to expectations , the feeding experiment showed that both NPs caused a signifi...

p>Wireworms are larvae of click beetles (Coleoptera: Elateridae) and are well known pests of economic importance. Knowing the species diversity in a particular area is important, as the ecological requirements and consequent management strategies of individual species vary. Morphological identification of wireworms is challenging; separating betwee...

The aegerolysin proteins ostreolysin A6, pleurotolysin A2 and erylysin A are produced by mushrooms of the genus Pleurotus. These aegerolysins can interact specifically with sphingolipid-enriched membranes. In particular, they strongly bind insect cells and to artificial lipid membranes that contain physiologically relevant concentrations of the mai...

Soil microorganisms influence biotic and abiotic stress tolerance of crops. Most interactions between plant symbiotic and non-symbiotic soil microorganisms and plants occur in the rhizosphere and are sustained through plant exudation/rhizodeposition. Bioaugmentation, i.e., the introduction or amplification of certain plant beneficial microbes (e.g....

We present a synthetic review and expert consultation that assesses the actual risks posed by arthropod pests in four major crops, identifies targets for integrated pest management (IPM) in terms of cultivated land needing pest control and gauges the implementation “readiness” of non-chemical alternatives. Our assessment focuses on the world’s prim...

Colorado potato beetle (CPB) is an agricultural pest of solanaceous crops, notorious for its rapid resistance development to chemical pesticides. Foliar spraying of dsRNA formulations is a promising innovative technology providing highly specific and environmentally acceptable option for CPB management. We designed dsRNA to silence CPB mesh gene (d...

Root-knot nematodes are considered the most important group of plant-parasitic nematodes due to their wide range of plant hosts and subsequent role in yield losses in agricultural production systems. Chemical nematicides are the primary control method, but ecotoxicity issues with some compounds has led to their phasing-out and consequential develop...

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera, Chrysomelidae), is an important insect pest of maize in North America and Central and Eastern Europe. In Central Europe, the larvae emerge in May and its three instars feed intensively on maize roots in June, causing plant lodging that leads to a loss of economic y...

Colorado potato beetle (CPB) is an agricultural pest of solanaceous crops, notorious for its rapid resistance development to chemical pesticides. Foliar spraying of dsRNA formulations is a promising innovative technology providing highly specific and environmentally acceptable option for CPB management. We designed dsRNA to silence CPB mesh gene (d...

Understanding the genetic background of drought tolerance in common bean (Phaseolus vulgaris L.) can aid its resilience improvement. However, drought response studies in large seeded genotypes of Andean origin are insufficient. Here, a novel Andean intra-gene pool genetic linkage map was created for quantitative trait locus (QTL) mapping of drought...

Abstract The immune system is one of the most complex systems, as it controls the interactions between microorganisms and hosts. Mammals have the most complex immune system, however insects also have their immune system and improved knowledge of it has an indirect effect on human life quality. It is difficult to assess the health significance and f...

The Spotted-wing drosophila (SWD), Drosophila suzukii (Matsumura, 1931) (Diptera, Drosophilidae) was recorded for the first time in Slovenia in autumn 2010. Shortly thereafter, it turned out to be one of the most important insect pests of soft and stone fruit in Slovenia and elsewhere. Within the expert work in the field of plant protection, more p...

Aegerolysins ostreolysin A (OlyA) and pleurotolysin A (PlyA), and pleurotolysin B (PlyB) with the membrane-attack-complex/perforin domain are proteins from the mushroom genus Pleurotus. Upon binding to sphingomyelin/cholesterol-enriched membranes, OlyA and PlyA can recruit PlyB to form multimeric bi-component transmembrane pores. Recently, Pleurotu...

Crop infestation with root-knot nematodes (RKN) and water deficiency lead to similar visible symptoms in the plant canopy. Identification of biotic or abiotic stress origin is therefore a problem, and currently the only reliable methods for determination of RKN infestation are invasive and applicable only for point-searches. In this study the appli...

Aegerolysin proteins from the fungal genus Pleurotus have been recently found to interact with ceramide phosphoethanolamine (CPE), a membrane sphingolipid that is specific to invertebrates. Moreover, the genomes of these fungi harbor nucleotide sequences that encode proteins with a membrane attack complex/perforin (MACPF) domain. When combined, aeg...

The cabbage maggot (also known as cabbage root fly [CRF]; Delia radicum L.) is a serious pest of brassicas. The pest's soil-dwelling larvae are especially damaging to young brassica transplants. In light of toxic soil insecticide phase-out novel biocontrol management solutions are sought for. Our research is focused on the development of a biologic...

Crop plants are subjected to various biotic and abiotic stresses. Both root-knot nematodes (biotic stress) and water deficiency (abiotic stress) lead to similar drought symptoms in the plant canopy. In this work, hyperspectral imaging was used for early detection of nematode infestation and water deficiency (drought) stress in tomato plants. Hypers...

The Western Corn Rootworm (WCR), Diabrotica virgifera virgifera LeConte, 1868, [Coleoptera, Chrysomelidae], whose larvae cause damage to maize roots, is an important economic insect pest in America and Europe. Its larvae are usually controlled by granular soil insecticides or insecticide-treated seeds. Biological control options, such as entomopath...

The number of active substances registered for wireworm control is decreasing. Consequently, inventorization programs were launched to find and identify potential wireworm biological control agents. Metarhizium brunneum Petch was isolated from an adult Agriotes sp. (Coleoptera: Elateridae) in Slovenia. The strain belongs to a phylogenetic lineage o...

Cabbage root fly (Delia radicum L.) control represents a major challenge in brassica production, therefore different management strategies for its control were tested in conventionally managed open field cauliflower production. Strategies included treatments with low risk methods such as nitrogen lime, the insecticide spinosad and the Beauveria bas...

The cabbage root fly (CRF; Delia radicum) is currently difficult to control as insufficient plant protection products are available, especially in organic farming. In this study the influence of two strains of the entomopathogenic fungi Metarhizium brunneum and Beauveria bassiana (Hypocreales), straw mulch, and nitrogen lime were investigated in re...

Spotted wing drosophila ( Drosophila suzukii (Matsumura, 1931), Diptera, Drosophilidae) management is difficult mainly because of its short generation time, polyphagy and serrated ovipositor, but also because its larvae can pupate in the orchard soil and are thus protected from insecticide applications. We hypothesized that insect-pathogenic soil f...

The management of soil-pests relies largely on conventional insecticides. Within the framework of the EU's PURE project, data were collected to assess the risk of soil-pest damage to grain maize in Europe in order to implement Integrated Pest Management (IPM) of soil-pests in a more practical and sustainable manner, thus optimizing the use of soil...

Grapevine leafroll disease is one of the most severe viral diseases of grapevine caused by Grapevine leafroll-associated viruses (GLRaVs). Physiological processes were monitored on grapevines with single (GLRaV-1) and mixed (GLRaV-1 and GLRaV -3) viral infection under greenhouse conditions from June to September, in vegetation period 2014. In the m...

European corn borer (Ostrinia nubilalis) (ECB) is an important maize pest in central and northern Europe. Presently it is controlled by insecticides or biological agents such as Trichogramma brassicae in several European countries, excluding Slovenia, where the pest’s pressure is highly variable and no appropriate mechanization is available. Lessen...

Within the framework of the EU project PURE, long-term experiments were conducted to evaluate two IPM strategies (IPM1 and IPM2) against current practice (CP) in winter wheat based (6 locations) and maize-based (3 locations) cropping systems. Furthermore 15 on-farm experiments were set up in grain maize to study the effect of specific IPM tools on...

A two-year study was conducted to evaluate the efficacy of biological control with optimally timed Trichogramma brassicae releases as an integrated pest management tool against Ostrinia nubilalis (Hübner; ECB) in on-farm experiments (i.e. real field conditions) in three European regions with dissimilar geo-climatic conditions, ECB pressure, and con...

Within the European Project PURE, on-farm trials were set up in five European countries to evaluate IPM tools against weeds and the European corn borer (ECB) in grain maize, compared to the conventional management (CON). On-station experiments were also conducted in three countries to evaluate two IPM levels against the CON in maize-based rotations...

Delia radicum L. or cabbage maggot is an important pest for Brassicaceous crops. There are currently no registered chemical control agents for its control in Slovenia. Fungal control agents for cabbage maggot were therefore sought among nine rhizosphere-compatible and plant growth-promoting, soil-adapted, and entomopathogenic species to cabbage mag...

White cedar (Thuja occidentalis L.) is commonly used as an ornamental plant in cut or free-growing hedges in all parts of Slovenia, regardless of the soil or climate conditions. The dominant variety is Emerald with a conical crown. A significant drying and dying of white cedars in an older hedge was observed in autumn 2010 in Ljubljana (Vič). When...

The root aphid Tetraneura (Tetraneurella) nigriabdominalis (Sasaki), (Pemphiginae: Eriosomatini) was recorded on corn roots (Zea mays L.) in August 2011 in northeast Slovenia in the village Benica. The species was classified morphologically and by molecular methods.

The influence of 0, 1.5 and 3% NaCl on the activity of halotolorent microorganisms was investigated in a pilot-scale, subsurface flow, and sand-gravel constructed wetland. Also, the influence of aeration and aeration with 2 g/L of saccharose in synthetic wastewater was investigated. Measurements of electron transport system(ETS) activity, optical d...

Early chemical-induced stress in Solanum tuberosum leaves was visualized using delayed fluorescence (DF) imaging. The ability to detect spatially heterogeneous responses of plant leaves exposed to several toxicants using delayed fluorescence was compared to prompt fluorescence (PF) imaging and the standard maximum fluorescence yield of PSII measure...

Vegetated drainage ditches (VDD) as a type of constructed wetland primarily serve to remove and store excess water associated with irrigation and storm events. Current research suggests using a VDD as an additional practice in the mitigation of surface water pollution. The VDD for water treatment of the Glinscica River was constructed in 2006. The...

Ecotoxicological analysis of the stream Glinščica in Ljubljana, Slovenia have shown increased pollution as well as toxicity in the stream. The reasons were found in the outflow from septic tanks and sewage system along the stream and in non-point sources of pollution from agricultural stormwater run-off. To demonstrate a natural way to reduce the p...

An ultra-sensitive digital imaging system was employed to visualize oxidative stress in intact L. minor plants exposed to Cd, Cu, menadione, AAPH, and ascorbate in real time. The increase of ROS production was assessed by measuring the rate of fluorescence intensity increases of the test medium supplemented with a fluorescing probe (dichlorofluores...

In order to find the optimal design characteristics of constructed wetlands for saline wastewater treatment, halotolerant microorganisms, isolated from the water of the Sečovlje salterns, were inoculated into the media of a pilot-scale constructed wetland (CW). The purpose of this study was to examine the influence of different salinities on the ef...

An experimental set-up which enabled non-invasive, real-time reactive oxygen species (ROS) visualization on a whole plant level was constructed. In the test organism, Lemna minor L. (common duckweed), apoplastic and symplastic oxidative stress was evaluated by exposure to menadione (50 μM), menadione (50 μM) + ascorbate (100 μM) or neither for cont...