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After the first record of the banded greenhouse thrips, Hercinothrips femoralis (Reuter, 1891) in Slovakia in 2008, a peculiar occurrence in an extreme subalpine environment of Podbanské (High Tatra Mts.), Slovakia, during the summer of the same year was observed. Since this species of exotic thrips is known to be almost sedentary, the mode of dispersal was hypothesized to be related to passive transport via weather currents. According to our observations of unintentional dispersal a test was conducted to research a previously unidentified introduction pathway of this species. Our preliminary results show that passive transport by humans plays a crucial role in the dispersal of H. femoralis.

The Bacillus amyloliquefaciens Y1 strain was evaluated for its effects on soil properties, pepper seedling growth, rhizosphere bacterial flora and soil enzyme activities. Y1 solubilised insoluble phosphate, produced chitinase, and released siderophores in plate detection assay. In order to evaluate the plant growth promotion potential in vivo, strain Y1 was grown in media containing chitin powder and complex fertiliser. The pot experiment was conducted by treating pepper seedlings with C1/1 (Y1 culture, 50 ml), C2/3 (Y1 culture, 33 ml), C1/2 (Y1 culture, 25 ml), F1/1 (complex fertiliser, 50 ml), F1/2 (complex fertiliser, 25 ml), and W (water) at 10, 20, 30, 40, and 50 days after transplantation (DAT). Plants receiving Y1 had 52% (C1/2) and 68% (C1/1) more root and shoot biomass than W, and 14% (C1/1) and 18% (C2/3) more compared to F1/1 at 80 DAT. Total numbers of flowers per plant at 80 DAT were found significantly higher with the application of Y1 having 34 (C1/1), 35 (C2/3), and 22 (C1/2) compared to 4 (W), 12 (F1/1) and 10 (F1/2). In addition, chlorophyll content in pepper leaves was found to improve with the application of Y1. Furthermore, Y1 has significantly improved nutritional assimilation of total NPK, population of total culturable bacteria and chitinase producing bacteria and activities of chitinase and dehydrogenase in soil. At 60 and 80 DAT, the number of B. amyloliquefaciens at C1/1, C2/3, and C1/2 ranged from 2.3 × 10⁴ to 4.6 × 10⁴ CFU/g of soil. Our results concluded that B. amyloliquefaciens Y1 has positive effects on soil properties and can be suggested as a bio-fertiliser to minimise fertiliser application in modern agriculture.

In June 2018, the presence of one adult specimen and one egg cluster of the North-American oak lace bug Corythucha arcuata were recorded near the village of Mužla, close to the Danube River, in southern Slovakia. They were found on leaves of Quercus cerris growing in a mixed stand. In August 2018, other specimens (nymphs and adults) were observed on Quercus robur leaves, near Čičarovce, in eastern Slovakia. This is the first record of C. arcuata in our country. The oak lace bug probably reached us while invading from Hungary, where heavy infestation is reported from several parts of the country.

A unique evaluation of the apple tree trunk bark damage caused by common vole and European hare was presented. Damage was found in an apple orchard under organic farming, in Central Moravia (Czech Republic), at 700 m a.s.l. There were two cultivated apple cultivars Red Spring and Melodie/Angold. Damage occurred in winter with the snow cover lasting from December to February. In total 1 012 trees and 95.7% of trees were damaged. The cv. Red Spring was damaged more than cv. Melodie/Angold. Almost 90% of the dead trees were killed by common voles. While hares damaged both cultivars equally, voles damaged the cv. Red Spring to a significantly greater extent (P = 0.04). The study confirms the need of further research on the development of methodologies for orchard protection from damage caused by small mammals.

The different materials and methods used to develop biopesticides with entomopathogenic nematodes (EPNs) still limit the quality of the final product, reducing field efficacy and complicating application strategies. Therefore, the objective of this review is to identify priority areas to improve the EPN formulation process based on the scientific and technological research developed so far. The results show great progress in the EPN survival time, from 7 days to 180 days, through two types of formulations: water dispersible granules and calcium alginate capsules. Also, EPNs formulated and applied as insect cadavers showed higher efficacy for the pest control than the EPNs applied in an aqueous solution. We consider that the priority areas of research are: automated massive formulation and exploration of new additives with better properties that may lead to increase the infectivity in the field. It is concluded that the study of these aspects requires a systemic approach with greater involvement of the invertebrate physiology and systems modelling disciplines.

Damage by the blueberry gall midge Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae) was found on different cultivars of highbush Vaccinium corymbosum L. at different localities of Lithuania. D. oxycoccana is a serious insect pest of blueberries in North America. In 1996, unusual damage on blueberries was observed in Europe. This is the first report of the blueberry gall midge occurrence in blueberry plantations in Lithuania.

We investigated moth larvae (Lepidoptera) developing in temperate forests in Central Europe shortly after the tree budburst (the "brumata-viridana complex"). Larvae were collected in southern Slovakia in May 2015 and May 2016 from young and mature trees of late flushing Quercus cerris L. and early flushing Q. pubescens Willd. Although Q. cerris yielded fewer species (40 species) than Q. pubescens (47 species), the rarefied number of species and the Chao index suggested a similar number of species on mature trees of both oak species. Both the total number of moth larvae in assemblages and the abundance of dominant species (pests) were significantly lower on Q. cerris than Q. pubescens. The results suggest the release of Q. cerris with delayed budburst from heavy infestations by folivorous moth larvae. Knowledge obtained can be applied in silvicultural and horticultural practices aimed to protect and maintain forest, fruit, and ornamental trees.

The use of stable isotopes to label an insect species, the Mediterranean fruit fly Ceratitis capitata (Diptera: Tephidae) (medfly) was investigated. Labelling allows mating and life history characteristics to be investigated experimentally. ¹³C₆-glucose was incorporated into the diet of medflies at various stages of development by adding it to larval media or providing adults with sugar water. Data was collected from egg hatching until the death of adults. The results show that stable isotopes successfully labelled medflies in laboratory conditions. There were significant differences between labelled and unlabelled treatments in terms of eggs hatching rates, larval development, pupae emergence, adult survival, and mating behaviour. Labelling during larval development, and combined labelling at the larval and adult stages, resulted in detectable values. Labelling in the larval stage had no effect on mating behaviour, but that in the adult stage did. This study demonstrates that it is possible to label adult medflies and to detect the label after mating.

Limnocharis flava (L.) Buchenau is among the most problematic rice weeds in Malaysia and is also reported to have developed multiple resistance to AHAS inhibitor bensulfuron-methyl and synthetic auxin 2,4-D. In this study, resistance across different AHAS inhibitors was characterised in a L. flava population infesting rice fields in Pulau Pinang, Malaysia. Dose-response experiments were conducted to determine the level of resistance to sulfonylureas, imidazolinone, triazolopyrimidine, and pyrimidinyl-thiobenzoate. Cross-resistance across different AHAS inhibitors was observed in the resistant L. flava population, exhibiting a high level of resistance to bensulfuron-methyl, while exhibiting a moderate level of resistance to metsulfuron-methyl and a low level of resistance to pyrazosulfuron-ethyl and pyribenzoxim. However, all resistant L. flava individuals were still sensitive to imazethapyr, penoxsulam, and bispyribac-sodium. Based on the results, it is likely that resistance to AHAS inhibitors in L. flava is conferred by target-site resistance mechanisms.

The host resistance level of pure line materials was assessed in the genepool for the purpose of breeding. The highest resistance to the pathogen was observed in bell-type pepper. Moreover, genetic diversity of pure lines was investigated using selected inter-simple sequence repeat (ISSR) primers. Generally, genetic markers showed genetic diversity, so that long-type pure lines were separated from the other accessions. This is the first report on host reactions of Turkish pure lines as breeding material. These results provide significant information for future pepper breeding programs.

Downy mildew of sunflower is a recurrent threat for crop production and a permanent challenge for resistance breeding. Since 2016, a new pathotype of the oomycete Plasmopara halstedii has been found in fields of cutting sunflower in Southern Germany. Infection assays based on sunflower differential lines identified the pathogen as pathotype 354 which has not yet been described anywhere else. The new pathotype readily infected the host lines Ha-304, RHA-265, PM13, 803-1, and Ha-335, whereas RHA-274, PM17, HAR-4, and QHP1 remained uninfected. It is the first isolate of Plasmopara halstedii to overcome the Pl-6 resistance of sunflower in Germany.

One of the biotic agents of yellowing and stunting in wheat and barley cultivations is Wheat dwarf virus (WDV) which is naturally transmitted by the leafhopper Psammotettix alienus (Dahlbom). WDV-Wheat and WDV-Barley isolates of WDV were transmitted to wheat and barley, respectively, using the leafhoppers under four temperature regimes of constant 20, 25, 30, and 35°C. Infection rate, symptom development and virus content of the virus-inoculated plants were determined and the data was statistically analysed. The results showed that the temperature of 25°C was associated with the highest infection rate caused by the viruses. Moreover, P. alienus nymphs were found to be more efficient vectors of WDV than adults, highlighting the importance of nymphs in the epidemiology of wheat dwarf disease. WDV-infected plants incubated at 35°C showed less symptoms than those kept at 20, 25, and 30°C. ELISA results showed that these plants had comparatively low virus content. However, there was no significant difference between the infection rate, symptom development and virus content in plants infected by WDV-Wheat or WDV-Barley.

Potato yields and infestation by P. infestans are related to the supply of potassium. Potassium was applied as soil fertilisation combined with split foliar applications or only as split foliar treatments at a maximum dose of 150 kg/ha K₂O in both strategies, Lord and Ditta cultivars were used. Additionally, water spraying was included as an alternative treatment in order to maintain uniform moisture in the rows of plants. Plants fertilised with foliar spraying only were more infested than plants fertilised with combined methods. The fertiliser increased the protection impact of copper treatments against P. infestans. This may suggest a possible synergistic effect in reducing the symptoms of the disease, however not always statistically significant in both cultivars. Plants sprayed with water but without soil application of fertiliser showed a statistically significantly higher infestation rate, both in Lord and Ditta cultivars, compared to plants with soil application of fertiliser but without watering.

The treatment of cucumber plants with Trichoderma atroviride TRS25 (TRS25) provided protection against infection by Rhizoctonia solani. In plants inoculated with the pathogen, nontreated with Trichoderma, disease symptoms were observed on the roots, shoots, and leaves while in plants treated with TRS25 the spread of the disease was limited. The induction of systemic defence response in cucumber against R. solani infection seemed to be strongly related to the enhanced synthesis of phenolic compounds in plants. HPLC analysis indicated remarkable increases in the concentrations of 23 phenolics belonging to hydroxybenzoic acids, cinnamic acids, catechins, flavonols, flavons, and flavanons in the plants without systemic disease symptoms. We suggest that the accumulation of phenolic acids, flavonoids and de novo synthesis of catechins may strongly contribute to cucumber protection against R. solani.

Botrytis cinerea, the causal agent of grey mould, is a predominant agent causing extensive postharvest and quality losses of apples in Tunisia and worldwide. Efforts to manage this disease have met with limited success. For this reason, the use of microorganism preparations to control fungal diseases as an alternative to fungicides became an urgent need. From a total of 60 epiphytic yeasts, 10 were assessed in vitro against B. cinerea and selected isolates showing antagonism were evaluated for their ability to suppress the grey mould in vivo. On Petri plates, the most promising strains (three strains of Aureobasidium pullulans, one Cryptococcus flavescens, and one Citeromyces matritensis) showed a zone of inhibition against the pathogen fungus not exceeding 10 mm. In vivo, these isolates showed a remarkable antifungal activity since they significantly reduced disease severity on apples from 63% to 95% compared to the control. In conclusion, the work has demonstrated that the three strains, L7 of Aureobasidium pullulans, L2 of Citeromyces matritensis, and L10 of Cryptococcus flavescens, were highly effective and can be used as potential biocontrol agents in controlling the post-harvest decay of apples caused by B. cinerea.

An experimental trial was conducted to determine the pathogenicity of Beauveria bassiana strain 202 (Bb-202) against multiple targeted sucking insect species that are serious pests of crops and ornamental plants. The insect species, Myzus persicae Sulzer (Hemiptera: Aphididae), Jacobiasca formosana Paoli (Hemiptera: Cicadellidae), Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), and Stephanitis nashi (Hemiptera: Tingidae) were exposed to conidia of B. bassiana at rates of 1.0 × 10², 3.5 × 10³, 5 × 10⁴, and 6.75 × 10⁵ conidia/mm² to determine the pathogenicity of B. bassiana. The fungal strain Bb-202 showed the highest pathogenicity to M. persicae and 100% corrected mortality observed in the treatments over 1.0 × 10² conidia/mm², followed by the J. formosana with the final corrected mortality of 86.6, 94.4, and 97.4% after 10 days of fungal inoculation with 3.5 × 10³, 5 × 10⁴, and 6.75 × 10⁵ conidia/mm², respectively. The strain Bb-202 also showed good pathogenicity to B. tabaci and corrected mortalities of 77.9 and 81.1% were recorded when exposed to 5 × 10⁴ and 6.75 × 10⁵ conidia/mm². Relatively weak pathogenicity was observed in S. nashi, in which the highest corrected mortality of 63.7% occurred at 6.75 × 10⁵ conidia/mm². Accordingly, the LC₅₀ and LT₅₀ values of concentrations 1 × 10⁵, 1 × 10⁶, 1 × 10⁷, and 1 × 10⁸ conidia/ml were calculated for M. persicae, J. formosana, B. tabaci, and S. nashi that were determined as 6.7 × 10⁴, 1.3 × 10⁶, 3.6 × 10⁶, and 1.2 × 10⁷ conidia/ml and LT₅₀ was observed as 5.2~8.24, 5.1~6.6, 7.2~9.0, and 7.9~9.6 in days, respectively.

The influence of the cultivation of a single crop (potato or winter rye) on mite assemblages was evaluated. Both crops were cultivated in a long-term monoculture (90 years). The response of mites to fertilisation treatment (mineral with manure or mineral alone) was also studied. It was hypothesised that the density of mites as a community and the density of particular mite groups are higher in winter rye crop in comparison with potato. Secondly, the fertilisation with manure is more beneficial for mites than the use of mineral fertilisers alone, both in winter rye and potato crops. Results showed significantly higher mite abundance in potato, mainly due to Prostigmata dominance. Oribatida and Gamasida groups were significantly more numerous in winter rye. The fertilisation type, except for the suborder Astigmata, had no significant influence on the mite community.

The trap catch of Agriotes species and dynamics of the occurrence of adult click beetles using pheromone traps were determined, and the relationship between the dynamics of the caught wireworms and the placement of traps in selected agricultural crops was investigated. The study was conducted in 2011-2014 in the fields of different crops at five localities in two regions in Poland. The effectiveness of trapping the Elateridae beetles using pheromone traps varied in different localities. The results of the analysis of variance indicate statistically significant differences in the number of A. lineatus beetles only in individual years of research. On average, most individuals of this species were observed in the first year of observation (72.62), and the least - in 2012 (18.5). Statistically significant differences in the occurrence of beetles in each month were observed for all species except A. obscurus. No statistically significant differences between populations of the tested Agriotes species were observed in different localities. Their effectiveness was influenced largely by weather conditions. Pheromone traps work well and can be a part of an assessment system for the integrated pest management of Agriotes species.

Damage caused by the Goji berry gall mite, Aceria kuko (Kishida, 1927) was observed on the leaves of Lycium chinense Miller (Solanaceae) in Brno in August 2016 and on L. barbarum L. in Popovice in September 2016. Aceria kuko is a pest of Asian origin which is common in China and occurs only sporadically on Goji berry plants in the European Union. This is the first observation of the Goji berry gall mite occurrence in the Czech Republic.

Blue sticky traps with and without pheromone capsules were used to monitor and control Frankliniella occidentalis Pergande (1895) (Thysanoptera; Thripidae) in pepper crop greenhouses in Tunisia. Traps containing pheromone capsules could catch significantly more thrips than those without capsules, proving their efficiency in attracting and controlling this pest. In fact, greenhouses with traps with pheromone capsules caught 585.1, 526.7, and 668.8 adults/trap in a greenhouse with 10 traps with pheromone capsules on April 12, 19, and 26, 2012, respectively. The capture in a greenhouse with five traps with pheromone capsules was about 456.2, 412.8, and 431 adults/trap while in a greenhouse with five traps without pheromone capsules, the capture of F. occidentalis adults numbered 198, 257, and 302 adults/trap for the same three dates. Furthermore, traps with pheromone capsules captured males and females in equal numbers while traps without capsules caught much fewer males than females: 218.2 males/trap on April 26, 2012 in a greenhouse with five traps with pheromone capsules and 212.8 females/trap, 322.4 males/trap, and 342.3 females/trap in a greenhouse with 10 traps with pheromone capsules. In neither case were the differences significant. In contrast, in a greenhouse with five traps without pheromone capsules, the number of adults was about 88.6 males/trap, a significantly lower amount than the number of females/trap (213.4). This indicates that this pheromone plays a double role as a sex pheromone and as an aggregation pheromone by attracting both sexes. In fact, this double attraction approach improved the efficiency of these capsules by preventing the mating of untrapped females with males. This induced a high percentage of males and led to a decline in the thrips population on pepper flowers. Ten blue sticky traps with pheromone capsules reduced the thrips population more effectively in one week only than the use of five sticky traps, which took two weeks to achieve the control.

The potential impact of future climate change on fruit fly species distribution was assessed in Uganda using two general circulation models (HADCM and CCCMA) and two future predicted CO₂ emission scenarios (A2 and B2), under both full and no species dispersal modes. Future ranges were overall projected to decline by 25.4% by year 2050. Under full-dispersal, D. ciliatus > C. cosyra > B. invadens ranges were predicted to increase, while the rest are likely to decrease. In the no-dispersal scenario, a significant average decrease in size of niches is predicted. Range losses are predicted higher under B2 than A2. Future niches will likely shift to northern Uganda. The results should assist in the development of climate change adaptive pest management strategies.

Alfalfa (Medicago sativa L.) is concluded to be the principal reservoir of Pea streak virus (PeSV, genus Carlavirus) which induces necrotic streaking symptoms in pea. This virus is prevalent in pea growing areas in the USA, but in Europe it was recorded only once almost 60 years ago. Recently, filamentous virus particles 600-700 nm long have been observed in examined plant sap of alfalfa with leaf malformation, local necrotic lesions and yellow spots on leaves. Four kilo base pairs nucleotide sequence of PeSV including partial replicase gene, triple gene block, and capsid protein (CP) gene has been determined. On the nucleotide level, the sequence of the CP has about 80% identity with the North American isolates of PeSV, however, on the amino acid level the sequence has more than 94% identity. This is the first sequence-based proof of PeSV presence in Europe.

Sugar beet yield loss was predicted from early observations of weed density, relative weed cover, and weed biomass using non-linear regression models. Six field experiments were conducted in Germany and in the Russian Federation in 2012, 2013 and 2014. Average weed densities varied from 20 to 131 with typical weed species compositions for sugar beet fields at both locations. Sugar beet yielded higher in Germany and relative yield losses were lower than in Russia. Data of weed density, relative weed cover, weed biomass and relative yield loss fitted well to the non-linear regression models. Competitive weed species such as Chenopodium album and Amaranthus retroflexus caused more than 80% yield loss. Relative weed cover regression models provided more accurate predictions of sugar beet yield losses than weed biomass and weed density.

The effect of a single chemical treatment against Ostrinia nubilalis (Hbn.) on thrips abundance on maize in south-eastern Poland was evaluated. Two insecticides: Karate Zeon 050 CS, containing lambda-cyhalothrin, and Proteus 110 OD, containing thiacloprid with deltamethrin, were tested. Maize was sprayed in the second ten days of July, during the abundant occurrence of O. nubilalis larvae, which coincided with the population peak of thrips on plants. The tested active substances showed high effectiveness against thrips, but a better effect, reflected in a decrease in thrips abundance, was found for the mixture of thiacloprid with deltamethrin. The tested insecticides significantly reduced the population of thrips for up to 14 days after treatment.

Prociphilus (Meliarhizophagus) fraxinifolii (Riley, 1879) (Hemiptera: Eriosomatidae) is an alien species in Europe that has been spreading quickly there. This paper presents the origin and current occurrence, classification, description, identification, and biology of this species. It also discusses the harmfulness and threats, especially the impact on host- plants and ecosystem, invasion rate and facilitating factors.

Natural parasitism of the European corn borer eggs (Hübner) by Trichogramma spp. (Hymenoptera, Trichogrammatidae) was assessed in sweet corn field in north-west Serbia, region Vojvodina at the localities of Ruski Krstur, from 2004 till 2007. The rate of egg parasitism in 2004 varied from 35.89% to 73.58%. The parasitism in 2005 was lower than in 2004. On four different sampling dates in 2005 parasitism varied from 28.48% to 57.05% and averaged 39.4%. In 2006 parasitism fluctuated between 9.31 and 62.9%, averaging 32.15%. In 2007 parasitism varied from 36.8% to 54.54% and averaged 43.48%. The egg parasitoid species was identified as Trichogramma evanescens (Westwood). The study showed that this natural enemy occurred constantly in sweet corn fields but its number greatly fluctuated from year to year.

Ditylenchus weischeri was recently reported in the provinces of Manitoba and Saskatchewan, Canada. Populations of D. weischeri from creeping thistle (Cirsium arvense L.) in Manitoba and D. dipsaci from garlic (Allium cepa L.) in Ontario were examined for their potential to grow on callused carrot (Daucus carota subsp. sativus) disks, alfalfa (Medi- cago sativa L.) and creeping thistle callus tissues, and pure cultures of eight fungal species, Botrytis cinerea, Fusarium solani, Rhizoctonia solani, Verticillium dahliae, Sclerotinia sclerotiorum, Cladosporium cucumerinum, Colletotrichum gloeosporioides, and Chaetomium spp. Ditylenchus weischeri and D. dipsaci could not be reared on any of the fungal isolates nor in the callus tissues of creeping thistle. In contrast to D. weischeri, D. dipsaci was successfully reared on the alfalfa callus tissue. On the callused carrot disks, with no media, an increase of 54 and 244 times the initial density of 80 nematodes was obtained for D. weischeri and D. dipsaci, respectively. Monoxenic rearing was performed using callused carrot disks to provide sufficient D. weischeri inoculum for the microplot study. The effect of D. weischeri on yellow pea varieties Agassiz and Bronco was determined in a microplot trial using initial densities of 0, 100, 200, 400, 800, 1600, and 3200 nematodes/plant. While it had no impact on pea grain yield, D. weischeri slightly reduced plant height, aboveground biomass, and pod length at the population densities of 1600 and 3200 nematodes/plant. The final population densities at harvest were not significantly different from the initial densities indicating the pea varieties were poor hosts to D. weischeri. The results of the present study indicate that D. weischeri is unlikely to be a pest of yellow pea for weather conditions of the Canadian Prairies.

The occurrence of fungal pathogens, associated with cumin production of Turkey, was determined during 2011 and 2012. A total of 379 isolates were classified as Fusarium oxysporum f.sp. cumini, F. solani, F. acuminatum, F. equiseti, F. sambucinum, F. avenaceum, Macrophomina phaseolina, Alternaria burnsii, A. alternata, A. infectoria, Embellisia sp., and Rhizoctonia solani. Pathogenicity tests showed that F. oxysporum f.sp. cumini, F. solani, F. equiseti, M. phaseolina, A. burnsii, and A. alternata were highly pathogenic. A. burnsii and F. oxysporum f.sp. cumini were the major risk factors for cumin cultivation in Turkey. To our knowledge, this is the first report on F. oxysporum f.sp. cumini, F. solani, F. equiseti, M. phaseolina, and A. alternata in Turkey.

The amount and spatial distribution of plants afflicted with cabbage root maggot (Delia radicum; CRM) and clubroot (Plasmodiophora brassicae) in winter oilseed rape crops were assessed in the Olomouc region (Northern Moravia, Czech Republic) over the course of 2012-2014. A total of 16 commercial rape fields were included in the assessments. Plants with tumours showed a significantly lower (P < 0.001) level of infestation induced by CRM (24% of plants infested) compared to plants without tumours (37% of plants infested). According to a generalised linear mixed model, plants with thicker hypocotyls are predisposed to significantly higher levels (P < 0.001) of root surface damage induced by CRM. The correlation analysis indicates rather weak or intermediate levels of correlation between the two variables (hypocotyls thickness × root surface damage induced by CRM). Both CRM and clubroot symptomatic plants showed a significant tendency for aggregation in rape crops, but not in all cases. Distributions of CRM and clubroot symptomatic plants were either significantly spatially dissociated or not associated in crops. Ovipositing D. radicum females showed some tendency to avoid zones with higher number of plants infected by P. brassicae. Distributions of CRM and hypocotyl thickness levels were significantly spatially associated in crops in several cases.

The occurrence of both diseases was evaluated for four years in a selected orchard where 22 different apple progenies, totalling 699 seedlings were planted. During this period, no chemical protection against the diseases was applied in the orchard, and the incidence of the diseases was rated using a 9-point scale (from 9 = not infected to 1 = very highly infected). For the finalisation of the results, each seedling was characterised by the highest rate of infection from all four years of the evaluation. The lowest mean level of mildew infection equal to 7.47 was observed in the progeny of Resista × McIntosh Wijcik. Concerning the scab, the best was the progeny of Resista × Karmína having a rating equal to 8.27. The highest level of segregation of seedlings having joint resistance to both diseases was found out in the progenies obtained by crossings of HL665 × HL782 and Resista × HL447.