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V prispevku je prikazan koncept sestavljanja škropilnih programov, katerega cilj je zagotoviti močno znižanje koncentracije ostankov fitofarmacevtskih sredstev v jabolkih ob obiranju (vsaj pod 0,01 mg/kg ali pod 0,005 mg/kg). Predstavljen je način izbora pripravkov za različna obdobja sezone ter sistem podaljšanih paralelnih karenčnih dob. Navedeni so prav tako nekateri alternativni pripravki, ki ob uporabi v drugem delu sezone v plodovih ne puščajo ostankov FFS. Prikazan je koncept presoje primernosti nasada za '0-residue' pridelavo ter posledice glede obstojnosti plodov v skladišču. Opisan sistem pridelave omogoča doseganje najzahtevnejših kakovostnih kriterijev trgovskih verig in je hkrati ekonomsko učinkovit. Podana so pojasnila o vrstah toksikoloških kakovostnih kriterijev trgovskih verig ter opisane najpogostejše težav, ki se pojavljajo pri doseganju le-teh.

In a two-year field experiment, six different weed control methods were studied. The methods were: use of the herbicide glyphosate (GL), use of herbicides based on acetic acid (AA), pelargonic acid (PA) and citrus essential oil (EO), mowing weeds with a thread trimmer (TT) and flaming of weeds with fire (FL). Alternative methods of weed control were significantly less effective than the use of herbicide glyphosate. Due to the lower efficiency of alternative methods, large yield losses have occurred, on average, 31 % at AA, 30.6 % at PA, 22.7 % at EO, 5.4 % at TT and 12.9 % at FL in two years. The cost of carrying out controls with alternative methods was significantly higher than the cost of GL. AA it was higher by 3.2-times, in PA by 7.1-times, in EO by 3.8-times, in TT by 3.8- times and in FL by 5.8-times on average in two years. To achieve a comparable control efficiency of GL, five applications of alternative preparations per year have to be performed, or four times mowing of weeds or five weed flaming operations per year.

The present study investigates the effect of exclusion of copper preparations from spray programs for disease control in integrated and organic tomato production systems on disease incidence, yield and fruit vitamin C, α-tocopherol and carotenoids content for Monroe, Optima and Paki cultivars. Open field trials were conducted in a randomized block system with four repetitions over two years. Treatment for plant disease control comprised four spraying programs, two within each production system. Yields were significantly affected by cultivar, pest management system and their interaction. Copper-free integrated and organic spraying programs were almost as effective in disease control as standard treatments which included copper preparations. The spraying program significantly affected the contents of vitamin C, α-tocopherol, phytoene, and β-carotene in fruits; however, the effect was cultivar related. The lycopene contents appeared to be unaffected by the spraying program or growing system.

Monografija z nalovom Priporočila za nekemično zatiranje pelinolistne ambrozije Ambrosia artemisiifolia L. holistično obravnava aktualno problematiko zatiranja alohtonih, invazivnih rastlinskih vrst, na primeru pelinolistne ambrozije. V publikaciji so nazorno predstavljene najpomembnejše mehanske metode in tehnike zatiranja ambrozije, učinki samih metod, kakor tudi učinki uporabe ter primerjava med posameznimi tehnikami zatiranja vrste. Posebno poglavje je namenjeno ekonomiki zatiranja plevelov v urbanem okolju, z uporabo metod krtačenja, uporabo ognja, pare ter s pomočjo biotičnih metod zatiranja ambrozije. Prav omenjeni moderni pristopi k zatiranju alohtonih plevelnih vrst so danes, zaradi ukinjanja uporabe številnih herbicidov na javnih površinah, še kako aktualni. Monografija je namenjena kmetijskim svetovalcem, pridelovalcem, ekologom, pa tudi širšemu krogu bralcev.

The preservation of biodiversity and the improvement of soil fertility have become important goals in orchard management; therefore, the standard approach of weed control in the understory of tree rows by repeated frequent use of herbicides needs to be replaced by more sustainable methods. This study presents a technique for establishing a permanent autoregulatory non-competitive plant community as an alternative to herbicide treatment. For a practical demonstration of this weed control method, an experiment was conducted in a pear orchard during the 2015–2019 growing seasons. A permanent plant community was created in a 1 m wide strip under the trees by seeding three different grass and herb mixtures. Two types of control plots were also established (weed control treated with the herbicide glyphosate and weedy control). Several inventories of the species composition of the studied communities were conducted each season. The relationship between the proportions of plant biomass of native, non-seeded plants, and seeded plants was evaluated. The results of this experiment show that the long-term undisturbed development of understory communities not exposed to herbicides or mechanical weed control causes only a limited, statistically non-significant reduction in yield.

Grasslands may mitigate rising levels of the atmospheric ‘greenhouse gas’ carbon dioxide by C sequestration in soil organic matter, depending on several environmental and management factors. The objective of this study was to examine the effects of long-term (19 years) different cutting frequencies (CFs), using equal amounts of mineral fertilisers (173 kg N, 40 kg P, and 150 kg K ha −1 year −1 ), on some sward and soil properties of previous extensively fertilised and utilised bio-diverse wet grassland. The impact of the study was directed towards the soil organic C and the apparent N budget. The CFs during the grassland experiment were cut at 2, 4, 6, 8, 10, and 12-weekly intervals. CF significantly affected the sward and the soil characteristics of the grassland. The average number of plants per plot was high at medium CFs and low at low CFs. The above-ground biomass yield was high at medium and at low CFs, and its N content was high at medium and at high CFs. Soil organic C stocks (SOCS), soil total N stocks (STNS), and soil bulk density showed significant interactive responses to CFs × soil depths (0 cm, 10–20 cm). Due to high amounts of symbiotically fixed N by legumes at higher CFs, the average above-ground biomass yields contained more N than was added with fertilizers. In contrast to the second soil layer, the first soil layer in those treatments was rich in SOCS and STNS. In treatment of 8-weekly intervals between cuts, the balance between N inputs and N taken-up by plants was closest to zero. Especially in those cases of low CFs (10 and 12-weekly intervals between cuts), the apparent N budget showed that N added with fertilisers was not fully removed from the system regarding above-ground biomass yields. Due to high SOCS and STNS in both soil layers it can be assumed that N surplus had been partly built into the soil organic matter. However, a part of N was uncontrollably lost from the soil–plant system. The obtained results highlight the complexity of the problem of C sequestration. In reality none of the treatments at the end of the experiment displayed everything, namely, high SOCS in both layers of the soil, low uncontrolled outputs of N from the system, high plant diversity and high yields of above-ground plant biomass.

Ena od posledic prilagoditev tehnike kmetijske pridelave z namenom varovati vode na vodovarstvenih obmocjih (VVO) je obcutno zmanjsanje intenzivnosti pridelovanja, ali celo opuscanje obdelave zemljisc (npr. povrsine neposredno ob ranljivih virih vode). Neprimerno vzdrževana zemljisca se pricnejo spreminjati v nekakovostno travinje, ki v naslednji fazi preide v pol-naravne rastlinske združbe, ki so pogosto sestavljene iz invazivnih tujerodnih rastlin. Izkusnje kažejo, da je povecevanje populacij invazivnih rastlin na VVO hitrejse, kot na obmocjih, ki niso pod vodovarstvenimi režimi. V tem delu smo skusali predstaviti del invazivnih rastlinskih vrst, ki so že prisotne na ozemlju RS, ali pa njihov pojav pricakujemo v bližnji prihodnosti. Predstavljeni so prakticni nasveti glede metod zatiranja razlicnih invazivnih vrst. Izpostavili smo tudi potrebo po ustreznem vzdrževanju pol-naravnih habitatov neposredno ob kmetijskih povrsinah, ki so sicer namenjeni varovanju voda in ohranjanju bioticne pestrosti, a imajo tudi pomembne bioloske funkcije za ohranjanje organizmov, ki regulirajo naravne procese, ki odlocajo tudi o uspesnosti pridelave kmetijskih rastlin. Dopuscanje nekontroliranega razvoja invazivnih rastlin na VVO lahko povzroci dolgorocno destabilizacijo pol-naravnih habitatov in tudi povecevanje stroskov pridelave kmetijskih rastlin ter stroskov vzdrževanja energetske, transportne in hidroloske infrastrukture v agrarni pokrajini v bodocnosti.

The monograph was prepared to educate agricultural advisors and farmers on the ways of pollution of ground and surface water with plant protection products (PPP) and to present the techniques for the prevention of their water pollution. It was prepared for the project SI-MUR-AT, an EU Cooperation Program INTERREG Slovenia-Austria 2014 – 2020. In the first part, the transition paths of PPP into the water are presented (leaching through the profile of the soil, surface run-off and point source pollution). The importance of soil’s pedological and hydrological characteristics for limiting PPP leaching and the methods for reducing the passage of PPP into the water are also presented. These are: the modified methods of PPP use and of rotation with preparations, improved risk analysis for leaching and runoff of PPP, changed methods of soil tillage, adapted application methods of PPP in the vicinity of surface water to reduce drift, retention measures for prevention of water runoff from arable land into the drain ditches and increased use of mechanical methods of weed control.

Trials were carried out in apple orchards of two different training systems to assess the relationship between spray drift and parameters of spraying with an emphasis on the sprayer’s travel speed when applying different solutions, such as pesticides or fertilizers, onto the apple trees. The assessments were based on the following factors: per cent of spay drift, two sprayers (axial- and radial-fan sprayer), two training systems (super spindle and modified slender spindle), spray droplet size (fine or coarse droplets) and the sprayer’s travel speed (5 vs. 10 km h−1). The studies were conducted in the spring and summer seasons under similar external weather conditions to test any seasonal effects that might occur. In this paper, all tested factors and interactions were found to have a significant effect on the spray drift during spray application. For instance, the increase in sprayer speed reduced the spray drift percentage. Other factors, such as sprayer type (axial fan and radial fan) and tree training system, had an impact on spray drift as well.

Four wheat cultivars with different levels of tolerance to Fusarium head blight (FHB) were grown in small plots and were inoculated with spores of Fusarium fungi during the anthesis. The harvested grain was cleaned by a special cleaner which separated it in 4 size fractions: F1 – >2.4 mm, F2 – 2.0–2.4 mm, F3 – 1.8–2.0 mm, F4 –

Based on time courses of individual antioxidant compounds, bark phenolic metabolism has been recognised to integrate ascorbate–glutathione system as a redox hub in Norway spruce defence against Ceratocystis polonica infection. Temporal courses of individual phenolics, thiols and ascorbate were studied in Norway spruce phloem over a 5-month period after inoculation at low density with Ceratocystis polonica. The initial reaction of Norway spruce 3 days after inoculation was characterised by significantly increased isorhapontin and taxifolin concentrations, accompanied by significantly lowered catechin contents. On later sampling dates, catechin concentrations within infected bark increased until September. The slightly accumulated astringin contents in April and May diminished at later sampling dates in response to infection. The isorhapontin levels strongly raised in April and were slightly lowered from June onwards. Compared to the controls, taxifolin concentrations were higher in the infected samples showing a double peak with maxima in April and June. The taxifolin values eased later but remained above the control levels. The initial response of the ascorbate–glutathione system to fungal infection was characterised by a significantly more oxidised glutathione pool, slightly more reduced ascorbate system and by higher glutathione reductase activity. Three weeks later an accumulation of thiols was observed, whereas total ascorbate was significantly lowered and the ascorbate redox state shifted towards more oxidised values. Until the middle of July a gradual increase of total glutathione was determined within the infected bark, which was accompanied by significantly increased cysteine contents, higher glutathione reductase activity, but significantly lowered total ascorbate contents. The increased pressure on the ascorbate system reflects its interaction with phenolics, as ascorbate is needed for reducing the phenoxyl radicals formed during pathogen defence.

The advantages and disadvantages of varying mixture proportion of crimson clover (Trifolium incarnatum L.) and Italian ryegrass (Lolium multiflorum Lam.), used as winter cover crops, and cover crop biomass management before maize sowing (Zea mays L.) were studied in a series of field experiments in Eastern Slovenia. Pure stands and mixtures of cover crops on the main plots were split into different cover crop biomass management subplots: whole cover crop biomass ploughed down before maize sowing, aboveground cover crop biomass removed before ploughing and sowing, or aboveground cover crop biomass removed before sowing directly into chemically killed residues. Cover crop and cover crop biomass management affected the N content of the whole aboveground and of grain maize yields, and the differences between actual and critical N concentrations in the whole aboveground maize yield. The whole aboveground and grain maize dry matter yields, and the apparent remaining N in the soil after maize harvesting, showed significant interaction responses to cover crop × management, indicating positive and negative effects. Crimson clover in pure stand provided high, and pure Italian ryegrass provided low maize dry matter yields and N content in the yields in all the observed methods of biomass management. However, within individual management, mixtures containing high proportions of crimson clover sustained maize yields and N contents similar to those produced by pure crimson clover. Considering the expected ecological advantages of the mixtures, the results thereby support their use.

Climatic changes have led to extreme weather events, with longer dry periods affecting forage production in mesic grasslands. The effects of grassland management and years with periods of low precipitation on herbage dry matter (DM) yield were studied in two-long term grassland experiments with different cutting and fertilization regimes for the period 2000–2012. In both experiments, the annual herbage DM yields had high correlations with the amount of precipitation. The correlation was stronger in frequent cuttings regimes. The management type and the year significantly affected the herbage DM yield in both experiments. There was also a significant management × year interaction. On average, over the whole observation period, the herbage DM yield of equally fertilized treatments in experiment I was higher in treatments with two cuts per season than in treatments with more cuts. Furthermore, longer periods of low precipitation exerted fewer effects on the DM yield of the two cuts treatments compared to higher cutting frequencies. However, the increase in herbage productivity in years following seasons with low precipitation was higher in the treatments with higher cutting frequencies than in those with two cuts per season. When the treatment, cut four times per year, received a higher amount of fertilizer than the treatment, cut twice per year (experiment II), the long-term average annual herbage DM yield was higher and the yield was less decreased by longer periods of low precipitation than the two cuts per year treatment. Despite the fact that the effects of different treatments were proved in both experiments, the differences in the DM yields among the treatments in low precipitation years were not high enough to recommend best-management practices for forage production on mesic grasslands in areas subject to increasing periods of low precipitation.

IZVLECEK Koliko se lahko približamo željam javnosti za obcutno zmanjsanje rabe pesticidov v kmetijski pridelavi in kaksne ucinke prinasa uvajanje alternativnih pristopov zatiranja skodljivih organizmov? V clanku so predstavljene nekatere okoliscine odnosa javnosti do postopkov registracije in regulacije rabe fitofarmacevtskih sredstev (FFS) v EU, zahteve po zmanjsanju porabe FFS, možnosti za zmanjsanje porabe FFS in nekateri ucinki uvajanja alternativnih metod zatiranja skodljivih organizmov. Znanstveni razvoj na podrocju varstva rastlin je zagotovil veliko novih sredstev in metod za nekemicno zatiranje SO, vendar uporaba le teh trenutno ne omogoca popolnega prenehanja rabe kemicnih FFS. Ena od ovir za obsežno zmanjsanje rabe kemicnih FFS je manjsa ekonomska ucinkovitost zatiranja SO z uporabo alternativnih metod in sredstev ter premajhna prilagoditev kmetijskih ekosistemov za izvedbo metod bioticnega varstva (spremembe pri obdelavi tal, v kolobarju, pri gojenju dosevkov, vzdrževanju robnih habitatov). Kljucne besede : pesticidi, hrana, varstvo rastlin, skodljivi organizmi, zatiranje ABSTRACT How much closer can we get to the public‘s desire for a significant reduction in the use of pesticides in agricultural production and what are the effects of introducing alternative approaches to the control of organisms harmful to plants? The article presents some of the conditions of public attitudes to the procedures for registration and regulation of the use of plant protection products (PPP) in the EU, the requirements for reducing the use of PPP, the possibilities for reducing the consumption of PPP and some of the effects of introducing alternative methods of pest, weed and disease control. Scientific developments in the field of plant protection have provided many new means and methods for non-chemical pest control, but the use of these currently does not allow the complete abandonment of the use of chemical PPPs. One of the obstacles to the extensive reduction in the use of chemical PPPs is the lower economic efficiency of the control of pests using alternative methods and resources and the lack of adaptation of agricultural ecosystems for the implementation of biological protection methods (changes in soil cultivation, in crop rotation, in cultivation of cover crops and in the maintenance of habitats surrounding production plots). Key words : pesticides, food, plant protection, plant pests, pest control

During the 2008–2010 growing seasons, an alternative ‘zero residue apple production system’ was compared with integrated apple production with cvs ‘Idared’, ‘Golden Delicious’, ‘Jonagold’ and ‘Gala’ in commercial orchards at several locations throughout Slovenia, using data envelopment analysis (DEA), and multi criteria assessment by an analytical hierarchical process (AHP). The principle of the ‘zero residue apple production’ is a combination of integrated (IP) and organic apple production. During the first 3 months of the growing season (1 April–30 June), pesticides used in IP with rapid degradation (8–10 applications) were used to control pests and diseases. During the second part of the season from 1 July to harvest, organic products (6–12 applications) were employed compared with 19–25 applications overall in IP. The goal of the alternative system was to reduce the amount of applied conventional pesticides by 40 % and to minimize pesticide residues in fruits to below the limit of 0.5 % of the legal maximum residue level (MRL) or below the residue concentrations of 0.005–0.01 mg/kg and to retain the high long-term level of yield, fruit quality, and net income per hectare. The number of pesticide residues was reduced from 4.2–5.5 in IP to 1.8–3.4 in zero residue cultivation, while 3 year average yields (class 1 fruit) were 4–9 % lower than in IP. The break even prices ranged from € 0.31 for Idared in IP, € 0.34 for ‘Elstar’ of both production systems to € 0.35/kg for zero residue cultivated ‘Golden Delicious’. Overall, a price increase of just € 0.02/kg for residue free apples would make this new ‘zero residue apple production’ profitable then representing a realistic alternative to the standard integrated apple production system.

To investigate the environmental advantages of using grass-clover binary mixtures over pure stands as winter cover crops, a serial of five field experiments (each designed as randomized complete blocks with four replicates) was carried out in eastern Slovenia. Trifolium incarnatum L. and Lolium multiflorum Lam. were sown in late summer as pure stands and binary mixtures. Pooled data calculated from all the experiments revealed that the soil mineral N in spring and accumulation of N by plants decreased with decreasing proportion of T. incarnatum in the binary mixtures, while the C:N ratio of cover crop organic matter increased. C accumulation was the highest when the seeding ratio of the binary mixture of T. incarnatum and L. multiflorum was 50:50. In the C and N environmentally sustainable management efficiency coefficients, three important traits of winter cover crops for environmental protection were given equal importance (low soil mineral N content in spring, high C accumulation in plants, and high N accumulation in plants). The coefficient was higher for binary mixtures of T. incarnatum and L. multiflorum than for pure stands of these crops, proving the complex environmental advantages of binary mixtures over pure stands.

Fruit pigmentation in ripening cv. ‘Gala, Schniga’ apples was monitored under the influence of fertigation weekly during 21 July–31 August 2009, i.e. 34 days before and 7 days after the optimal harvest date in Slovenia. The soil was a heavy loam clay with high humus content (2.8 %) and high acidity (low pH 4.9). The spectral indices NDVI (Normalized Difference Vegetation Index) and NAI (Normalized Anthocyanin Index) were obtained by a PA 1101 on attached fruit on the transition between the ground and blush colour of the fruit surface. NAI increased slowly from 0.25 to 0.6 two weeks prior to optimum maturity. NDVI values fell from 0.9 to 0.2 before and during ripening, with significant changes starting ca. 3 weeks before and during the week after the optimum harvest date. Fertigation delayed fruit ripening viz harvest date by ca. 4 days. Fertigation delayed changes in the intensity of the fruit’s epidermal pigments, expressed as NDVI for 1 week and NAI for 4 weeks, respectively, but had no significant effect on fruit colour or NDVI and NAI values at the optimal harvest date. At this time, those fruits from the fertigated trees were firmer with a lower starch index compared with the un-fertigated control. Statistically, highly significant correlations were found (p ≤ 0.01) (r = 0.35 to r = 0.91, R2 = 0.11–0.83) between all the studied spectral and standard parameters i.e. fruit fresh firmness, soluble solids content and starch index.

Field trials were carried out from 2008 to 2011 at Maribor, Slovenia to determine the effect of new copper fungicide formulations on the copper content in apple fruits, separated in peel and flesh, of seven cultivars at harvest. Apple trees were treated 12–18 times per season with formulations based on copper oxychloride or sulphate (trial standards), copper hydroxide and their complexes or chelates with amino acids, peptides, EDTA, urea, and octanoic or gluconic acids at the same rate of 200 g of pure copper ions (Cu2+) per hectare irrespetive of the product. Copper formulations were applied with Teejet 800067 flat fan nozzles mounted on a vertical boom of the sprayer, which gave a droplet volume median diameter (VMD) of 120 microns and 130–180 droplet impacts per square centimeter, as determined on water sensitive papers. The new formulations of copper in the form of salts of fatty acids or organic complexes or chelates had a higher penetration rate into apple fruit tissue than the traditional formulations based on Cu-hydroxide, Cu-oxychloride and Cu-sulphate. The copper content in the fruit depended on the ratio between copper solubility in the formulation, rate of penetration into the fruit and stability of the copper fungicide deposit on the fruit surface. Despite being applied at lower hectare rates, frequent applications led to the exceeding of the permitted EC maximum residue level of 5 mg/kg fresh mass (FM). MRL was most often exceeded with the application of formulations based on Cu-octanoate and Cu-gluconate and less often in case of the application of complexes of copper with amino acids, peptides or urea. A comparison of the copper content between different cultivars showed that cv. ‘Jonagold’, ‘Golden Delicious’ and ‘Elstar’ accumulated more cooper than other cultivars. Copper concentrations in the peel exceeded that of the flesh at least twice. The potential effects of accumulation of copper in woody tissue of bearing shoots after long-term application of highly systemic copper formulations on growth and blooming of apples are discussed too. Some apple growers may not be aware of much higher penetration rate of these new copper products (fungicides, fertilisers or plant strengtheners) and should be warned about the necessity to adapt their spraying schedules despite applications of a low hectare rates of copper, i.e. the number of treatments and proper seasonal timing, to avoid exceeding of EU MRL of copper in fruit.

Farmers are interested in producing popcorn under organic production systems and propane flaming could be a significant component of an integrated weed management program. The objective of this study was to collect baseline information on popcorn tolerance to broadcast flaming as influenced by propane dose and crop growth stage at the time of flaming. Field experiments were conducted at the Haskell Agricultural Laboratory of the University of Nebraska, Concord, NE in 2008 and 2009 using five propane doses (0, 13, 24, 44 and 85 kg ha −1 ) applied at the 2-leaf, 5-leaf and 7-leaf growth stages. Propane was applied using a custom-built research flamer driven at a constant speed of 6.4 km h −1 . Crop response to propane dose was described by log-logistic models on the basis of visual estimates of crop injury, yield components (plants m −2 , ears plant −1 , kernels cob −1 and 100-kernel weight) and grain yield. Popcorn response to flaming was influenced by the crop growth stage and propane dose. Based on various parameters evaluated, popcorn flamed at the 5-leaf showed the highest tolerance while the 2-leaf was the most susceptible stage. The maximum yield reductions were 45%, 9% and 16% for the 2-leaf, 5-leaf and 7-leaf stages, respectively. In addition, propane doses that resulted in a 5% yield loss were 23 kg ha −1 for the 2-leaf and 7-leaf and 30 kg ha −1 for the 5-leaf stage. Flaming has a potential to be used effectively in organic popcorn production if properly used.

This study was carried out to determine the level of retention of the mycotoxins deoxynivalenol (DON) and nivalenol (NIV) during 120 days of storage (aging) of flours produced from organic wheat grain naturally infected with Fusarium fungi. Three types of flour (standard white flour prepared by a roller-grinder mill - IRG, whole-grain flour produced by a hammer-crusher mill - IHC and whole-grain flour prepared by a millstone - OMS) were packaged in food-grade paper or polypropylene plastic bags and stored at two different storage temperatures (constant 10 °C or 25 °C). The concentrations of DON and NIV were measured prior to and after storage by means of HPLC-UV detection methods. After 120 days of storage, the concentrations of DON and NIV decreased between 0% and 29% compared to the initial measurements, depending on the combination of experimental factors. The greatest decrease in mycotoxin concentration was observed in the IHC and OMS flours packaged in paper bags and stored at 25 °C. The smallest decrease in mycotoxin concentration was observed in the IRG flours packaged in sealed plastic bags and stored at 10 °C. Statistical analysis showed that the level of retention of DON and NIV depended significantly on the type of packaging material, but did not depend on the type of flour or the storage temperature.

Field experiments were conducted over three consecutive growing seasons (20042–2006) to determine the effect of use of drift-reducing nozzles (ISO 03 code) on biological efficacy of fungicides for control of winter wheat diseases and their effect on grain yield. Four drift-reducing flat fan nozzles (VMD 270–440 μm) were compared with three standard nozzles (VMD 170–210 μm) at 300 l ha−1 spray volume. Commercial fungicide mixtures based on 12 different active substances were applied twice a season (BBCH 36–38 and 61–63). When controlling powdery mildew (Blumeria graminis) and wheat brown rust (Puccinia recondita) differences in efficacy of fungicides applied by standard or drift-reducing nozzles were small and mostly non-significant. The differences noticed at control of leaf blotch (Septoria tritici) depended a lot on the combination of growing season and fungicides applied. No general rule could be made regarding to the efficacy of fungicides for control of septoria leaf blotch. The greatest differences were observed by control of fusarium head blight (Fusarium spp.) and septoria glume blotch (Septoria nodorum) where the decrease (5–15%) of fungicide efficacy was determined when using drift-reducing nozzles. Decrease of biological efficacy of fungicides due to the use of drift-reducing nozzles however did not have a significant effect on the grain yield in most of the fungicide programs. According to our results the use of drift-reducing nozzles could be recommended without limitations to wheat producers applying wheat production systems similar to those in our experiment.

A comparison of the biological efficacy of pesticides applied against some apple pests with standard versus drift-reducing nozzles was made in trials in intensive orchards in Slovenia. Standard and drift-reducing nozzles were compared by applying 350 L spray per hectare. No significant differences in acaricide/insecticide efficacy between the types of nozzles could be observed when controlling fruit tree red spider mite (Panonychus ulmi) and apple rosy aphid (Dysaphis plantaginea). However, drift-reducing nozzles reduced the efficacy of insecticides against the codling moth (Cydia pomonella), green apple aphid (Aphis pomi) and apple leaf miner (Leucoptera malifoliella).

Vdihavanje peloda vrst iz rodu Ambrosia lahko povzroci preobcutljivostne reakcije. Krma za prostoživece ptice je eden od dejavnikov, ki pripomorejo k sirjenju omenjenih rastlin. Leta 2010 so zato k Direktivi o nezaželenih snoveh v živalski krmi (2002/32/ES) dodali aneks, da lahko krma za živali, ki vsebuje nezmleta žita, vsebuje do 50 mg semen vrst iz rodu Ambrosia v kilogramu krme (UL L 290/54). Podatkov o vsebnosti semen te rastline v krmi je zelo malo, zato smo z mikroskopsko metodo preiskali 40 vzorcev krme za prostoživece ptice. Semena ambrozije je vsebovalo 20 vzorcev oziroma 50 %. Ugotovljeno stevilo semen v kilogramu posameznega vzorca je bilo od 2 do 146 (10 mg do 774 mg). V skladu s predpisi smo vsebnosti preracunali relativno na vzorec z 12 % vlage in ugotovili, da je dovoljeno mejo presegalo 5 vzorcev (12,5 %).

The research aims to demonstrate the basic system elements of a prototype automated orchard sprayer, which can deliver pesticide spray selectively with respect to the characteristics of the targets. The contour of the apple tree canopy was detected by ultra sound sensors Prowave 400EP14D and appropriate electronics. Ultra sound signal was processed by a personal computer and fed in real-time to spraying nozzles which open and close in relation to the canopy structure. The current project focuses on developing the system components for spraying an individual tree. The evaluation was performed in field experiments by detecting deposits on leaves and water sensitive papers (WSP). The demonstrated concept of precise application of pesticide sprays supports a decrease in the amount of delivered spray, thereby reducing both costs and environmental pollution by plant protection products.

V letu 2013 smo na dveh kmetijah ugotavljali učinkovitost sedmih škropilnih programov za zatiranje bolezni čebule. Poskusne parcelice so bile razporejene v naključnem blok sistemu v štirih ponovitvah. Ocenjevali smo stopnjo napada škrlatne pegavosti (Alternaria porri), stopnjo učinkovitosti po Abbotu, pridelek in delež propadle čebule. Pri stopnji napada s škrlatno pegavostjo ni bilo statistično značilnih razlik med škropilnimi programi. V prvem poskusu je bila ugotovljena najvišja stopnja učinkovitosti po Abbotu pri škropilnem programu sestavljenem iz kombinacije mankozeb + metalaksil-M + azoksistrobin. V drugem poskusu nismo ugotovili statistično značilnih razlik. Pridelki čebule so bili najvišji pri obravnavanjih, kjer smo čebulček ob sajenju razkužili in čebulo nato med rastno dobo škropili z bakrovimi pripravki (prvi poskus) ali s kombinacijo mankozeb + metalaksil-M + azoksistrobin + iprodion (drugi poskus). Slednja kombinacija, brez uporabe snovi iprodion, se je izkazala kot najučinkovitejša glede zmanjšanja izgub pridelka čebule, ugotovljenih ob spravilu čebule, ne glede na razkuževanje čebulčka ob sajenju. In 2013, field trials were carried out at two different farms in the Ptuj region. We assessed the effectiveness of seven spraying programs for controlling onion diseases. The experimental plots were arranged in a random block system in four repetitions. We estimated the rate of attack of purple blotch fungus (Alternaria porri) on the leaves, the level of fungicide efficiency, the yield and yield losses caused by fungi attacking the bulbs. There were no statistically significant differences between farms when comparing the blotch attack rate. The highest level of efficacy of the fungicide programmes was achieved by a program consisting of applications of mancozeb + metalaxy-M + azoxystrobin. At the first farm, yields were highest in plots where disinfected onions were planted and in plots were copper preparations were applied as a foliar spray, as well as at a second farm in plots where a combination of preparations containing mancozeb + metalaxyl-M + azoxystrobin + iprodione was applied. The lowest rate of yield loss (disinfected and non-disinfected onions) was determined in the plots treated with a combination of mancozeb + metalaxy-M + azoxystrobin.