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Ideas on the European stone fruit yellows – as an entomologist can see them
30-34Views:196The European stone fruit yellows (ESFY) is an important endemic disease in Europe which causes in both, the Mediterranean countries and Central Europe serious damage. Its pathogen is the ‘Candidatus Phytoplasma prunorum’. The treatment and healing of the diseased trees and plantations with chemicals do not promise success. Thus, prevention may be the only solution. The transmission and spread of the pathogen happen by infected propagation material (grafting) or a vector (the psyllid, Cacopsylla pruni). Mechanism of the pathogen’s transmission and population dynamics of the vector have been extensively investigated in several European countries, which may allow by the control of C. pruni even to hold back the disease. Diseased stone fruit trees and wild Prunus spp. as main host species play an important role in maintaining and spreading the pathogen. C. pruni collects the pathogen by feeding on these plants and it carries persistently ‘Ca. P prunorum’. Researchers in Hungary have been characterized the disease only in terms of plant pathology, but neither the significance of the vector nor the role of wild Prunus spp. have been studied. This summary intends to give clues to these researches, that not only axe and saw should be the instruments of national control, but knowing the role and population dynamics of the vector the stone fruit production should be more successful.
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Old-new disease is maize smut (Ustilago maydis)
43-46Views:216Corn smut disease (Ustilago maydis) is one of the most common maize diseases. In the previous years the disease lost some from its importance, however nowadays it turns into more and more important and widespread one. The control encounters great difficulties, therefore it should be emphasized the preventive and resistance-based protection.
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Sour cherry anthracnose and possibilities of the control with special regard to resident Glomerella population in sour cherry plantations of East Hungary
12-17Views:153Anthracnose is considered one of the most destructive diseases for sour cherry production due to the rapid development of the disease on fruits. Glomerella cingulata (Stoneman) Spauld. & H. Schrenk (anam.: Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. in Penz.) has been the fungal pathogen responsible for anthracnose in last decades. Yield losses greater than 90% may occur under epidemic conditions. C. acutatum (J.H. Simmonds, 1968) strains were isolated of sourcherry plantations in East Hungary and this pathogen, new for Hungarian microbiont became recently dominant. Contrarily to the former species it is certainly transmitted with ants during fruit ripening. About third of strains proved to be cutinase producers that enable them to actively penetrate via cuticule, and these strains infect directly berries of blackberry, grape and tomato as well as plum and apple. Most of cutinase negative strains could also infect these fruits after mechanic injury. All strains of both species produce amylase, cellulase, lecithinase, lipase, polyfenoloxydase and protease in vitro, although the activity of these enzymes highly varied in the medium. The only C. acutatum strains produced noticeable amount of chitinase. Strains, tolerant to recently applied fungicides to control the anthracnose, could be isolated of sour cherry plantations that might be the cause of ineffectiveness of control measures in 2010. The mycofungicide containing mixture of three Trichoderma species in oil carrier could efficiently depress the development of anthracnose in ripening sour cherry.
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Review of the biology of plant psyllid (Cacopsylla pruni, Scopoli 1763), and its role in the spreading of European stone fruit yellows, ESFY-phytoplasma with Hungarian data
25-33Views:360The European stone fruit yellows (ESFY) phytoplasma disease caused by pathogen ’Ca. Phytoplasma prunorum’ induces serious damages in cherry, sour cherry, peach, and apricot orchards mostly in Europe. Its known vector is the plum psyllid (Cacopsylla pruni). Many articles report on the biology (morphology, taxonomy, life cycle etc.) and the method of transmission of the pathogen by the vector, and the possibilities of their control. This paper reviews our knowledge about the vector, and summarises the results of an inland research carried out in a northeastern Hungarian apricot orchards. Our goal was to show some important data for the farmers or anyone who is interested in this disease and its vector. And give some known method that we can protect our orchards against them to prevent the appearance of the disease. As the psyllid that became infected with the pathogen can hold its infectionous capacity during their lifetime, it is very important to have enough knowledge about their lifecycle, that we can determine the right time and method to control them. We also have to know how to identify them; therefore, this paper lists several important data which can be helpful. The most important keys of identification are their wing color, which dark borwn in the apex and brown is in the remaining part of the forewing. The length of the antennae is also an important factor, since other genuse’s species have longer antennae than twice the width of the head. C. pruni has as long antennae as twice the width of the head. They return to Prunus species in early spring and we have to protect our orhards in this period against them. We have to use preparations with a knock down effect on them to prevent the inoculation of the pathogen into the trees in our orchards.
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Susceptibility of stem infected sweet corn hybrids to common smut disease
55-57Views:428The common smut of maize (corn smut, Ustilago maydis /DC/ Corda) can cause large economic losses in susceptible sweet corn hybrids as well. The protection against this pathogen is fundamentally based on prevention. Many methods to control corn smut have been recommended or evaluated, including crop rotation, sanitation, seed treatments, modification of fertility, and biological control. In spite of these frequently mentioned control strategies, the host resistance seems to be the only effective method to manage common smut in those areas where Ustilago maydis is prevalent.
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A dual infection of two microscopic fungi on common milkweed (Asclepias syriaca) in Hajdúság region (East-Hungary)
189-195Views:195Common milkweed (Asclepias syriaca L.) is one of the most noxious and invasive weed species in Hungary. A. syriaca invades arable lands, horticultural and forestry plantations, natural and semi-natural habitats too. In cases of field crops it can cause considerable yield losses mostly in maize (2–10%), soybean (12–32%) and sorghum (4–29%), but only with high rate of coverage. It can also increase these problems that the common milkweed can be serve as reservoir and host for viruses, other pathogens and pests.
Because of the importance of common milkweed and in spite of demand to develop effective biological control, until now has not been developed a proper control program against A. syriaca. The aim of our research was to identify the necrotrophic fungal pathogens, which were involved in notable disease occurrence on this weed in different parts of Hajdúság region of Eastern-Hungary in 2016.
To the isolation of fungi from leaves and their identification were based on morphological colony characters on potato dextrose agar (PDA) and Sabouraud dextrose agar (SDA). To the description of conidia features were used PDA for Alternaria and synthetic low-nutrient agar (SNA) for Fusarium species, respectively. The examination of axenic cultures revealed that the fungi isolated from the leaves of common milkweed were Fusarium sporotrichioides and Alternaria alternata. -
Phytoplasma diseases on fruits in Hungary
24-29Views:175In the last twenty years, three phytoplasma diseases were identified in Hungary, viz. European Stone Fruit Yellows (ESFY) (caused by Candidatus Phytoplasma prunorum), pear decline (caused by Candidatus Phytoplasma pyri), and apple proliferation (caused by Candidatus Phytoplasma mali). Candidatus Phytoplasma prunorum was isolated from apricot, peach, plum and japanese plum. Cacopsylla pruni the vector of ESFY was also isolated and identified. Infection of Candidatus Phytoplasma pyri was diagnosed from pear and Candidatus Phytoplasma mali was found on apple and pear. The three phytoplasmas cause different damages on their host plants. The most economically important phytoplasma disease is the ESFY. It seriously impairs apricot and japanase plum trees. After infection of apricots and japanese plums show yellowing and defoliation, and within a few years die in apoplexy-like symptoms. The disease on japanese plum is so severe that this fruit practically can not be cultivated in Hungary. Pear decline is the most serious problem especially in intensive pear plantations. The vector Cacopsylla pyri, C. pyrisuga and C. pyricola can be found in almost all pear orchards. Because of the regular presence of psyllids in intensive pear orchards the insecticide control is necessary. Apple proliferation is not an important disease in Hungary. All of our isolations of ’Candidatus Phytoplasma mali’ occured in organic orchards and record was not available in Hungary lately.
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Laboratory and small plot fungicide trials to control potato late blight (Phytophthora infestans) next to Sepsiszentgyörgy town (Romania)
72-72Views:127Our experiments were carried out during 2009 and 2010 years on Szépmező field, next to the Sepsiszentgyörgy town, Kovászna county, Romania. The experimental area situated at 520 - 580 m altitude, its soil is a humus rich chernozem, the yearly average temperature is between 7 - 8 oC, the precipitation is 500 - 600 mm/year. 7 different fungicides efficacy were studied for control to potato late blight disease caused by Phytophthora infestans on three potato varieties, viz. Ostara, Santé and Desirée.
In the laboratory the fluanizam (500 g/L, ALTIMA 500) fungicide was the best in inhibition of growing fungus while on the field trial plots cymoxanil + famoxadone (22.1 + 16.6%, EQUATION PRO WP*) and metalaxyl** + mancozeb (200 g/L + 1.600 g/L, RIDOMIL MZ 72WP) were the most effective. This facts were confirmed by statistic Duncan-test and data of yields.
The appearance of Phytophthora infestans epidemic was influenced by the climate conditions too during May and June when the minimum temperature was 12 oC, and the maximum 20 oC, the rain quantity more than 120 mm, the air humidity above 75%, these conditions promote the appearance and spread of fungus.
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Biological control of sweet chestnut on Pécsbánya, Hungary
77-81Views:252The supervision of plant hygiene of sweet chestnut grove on Pécsbánya (South Hungary) started more than four years ago. Hypovirulent strains were applied as a biological process to control Cryphonectria parasitica fungus which causes the chestnut blight disease. By now the performed interventions have shown obvious results, the vitality of the trees has greatly improved, the amount of harvested nuts is increasing, and the hypovirulent strain has been spreading within the area. During plant health inspection the galls of chestnut gall wasp (Dryocosmus kuriphilus) was found in the year of 2015, which is the obvious symptom of new occurrence of the pest. The pest was eradicated by destroy galls, which allows taking out of consideration the damage by now in this area.
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Cytochrome b diversity of Hungarian Botrytis cinerea strains
18-21Views:120In the mitochondrion of eukaryotes, cytochrome b is a component of respiratory chain complex III. Cytochrome b is encoded by the
cytochrome b (CYTB) gene located in the mitochondrial genome. The fungicidal activity of QoIs relies on their ability to inhibit mitochondrial respiration by binding at the so-called Qo site (the outer quinol-oxidation site) of the complex III. Since their introduction, QoIs (like azoxystrobin) have become essential components of plant disease control programs because of their wide-ranging efficacy against many agriculturally important fungal diseases like grey mould on various crops. QoI resistance primarily arises from a target-site-based mechanism involving mutations in the mitochondrial CYTB. As the management of grey mould is often dependent on chemicals, the rational design of control programs requires the information about the diversity of genes connected with resistance in field populations of the pathogen.
Monospore B. cinerea field isolates has been collected during 2008-2009 from different hosts in Hungary. PCR fragment length analysis
indicated the high frequency presence of type large intron in the isolates while in a few strains G143A substitution could also be detected.
These results indicated the heterogeneity of CYTB in the Hungarian B. cinerea populations, which possibly involve the heteroplasmy of this
mitochondrial gene, moreover indicates the existence op azoxystrobin resistant populations in Hungary.
This work was supported by NKFP-A2-2006/0017 grant. Erzsébet Fekete is a grantee of the János Bolyai Scholarship (BO/00519/09/8). -
Effect of fish feed containing two Chinese herbal extracts (Ganodema Iucidum and Lonicera japonica) on the non-specific immune system of Nile tilapia, Oreochromis niloticus (preliminary results)
9-14Views:131The effect of two Chinese herbs (Ganoderma lucidum and Lonicera japonica) on non-specific immune response of tilapia was examined. In addition to the control (no herbs), three diet variations were used. These contained 1.0% of Lonicera, 1.0% of Ganoderma and a mixture of Ganoderma (0.5%) and Lonicera (0.5%). The respiratory burst and phagocytic activity of blood leukocytes were monitored. Three weeks after feeding, the fish were infected with Aeromonas hydrophila. The results of this study showed that feeding tilapia with Ganoderma and Lonicera alone or in combination enhanced the phagocytosis of blood leukocytes, but not the respiratory burst activity. Both herbs, when used alone or in combination, reduced mortality after challenge with A. hydrophila. The highest mortality was observed in the control fish – 56.66%, and fish fed with Lonicera extract – 43.33% while 30% of fish died in the group fed with Ganoderma and the lowest mortality (20%) was observed when the fish were fed with a combination of the two herbs. It can be concluded that the herb extracts added to this diet act as immuno-stimulants and appear to improve the immune response and disease resistance of tilapia.
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Effect of two different cropyear and the agrotechnological factors on the agronomic characteristic of the winter weat in a lon-term experiment
143-149Views:137We studied the effects of crop rotation, fertilization and crop protection technologies on occurence of the major ear- and leaf-diseases (powdery mildew, helminthosporiosis, leaf rust, Fusarium wilt) and the degree of lodging in the winter wheat variety Mv Pálma in two very different years (2006/2007=dry; 2009/2010=rainy). The experiments were carried out at the Látókép Experimental Farm of the University of Debrecen CAAES in triculture (pea-wheat-maize) and biculture (wheat-maize) at five fertilization levels by applying three different crop protection technologies (extensive, average, intensive).
In the cropyear of 2006/2007, the disease severity of leaf diseases was higher than the average in both crop rotations in spite of the fact that the weather during the whole vegetation period was dry. Infection by powdery mildew, helminthosporiosis and leaf rust increased with increasing fertilization, the highest infection was measured at the highest fertilization level (N200+PK) in the extensive crop protection technology. According to the results, no infection of ears by Fusarium and no lodging occurred in either bi- or triculture due to the dry year. The extremely rainy weather in 2009/2010 was favourable not only for the vegetative development of the stand, but also increased the occurance of leaf-, stalk- and ear-diseases and a high degree of lodging was observed. The highest infection by powdery mildew was observed in the plots with the highest fertilizer dosage under an extensive crop protection technology. A much higher helminthosporiosis infection was measured than in the cropyear of 2006/2007. The wet weather and higher than average temperature promoted the occurence and spreading of leaf rust. Under an extensive crop protection technology, a leaf rust infection of 24% and 31% was detected after maize and pea as a forecrop, respectively, in the N200+PK treatment. As opposed to 2006/2007, the disease severity of Fusarium was 3–8% and 2–7% in the control after maize and pea as a forecrop, respectively. This value, similarly to that of other pathogens, increased with increasing fertilization levels. Due to the large vegetative mass, a significant lodging was observed in the wheat stands in both bi- and triculture (17–100%, 12–100%). -
The efficacy of combining paraffin oil with conventional fungicide treatments against grape powdery mildew in Eger
173-180Views:174We aimed to test the combination of paraffin oil (PFO) with regular fungicide treatment to assess its efficacy against grape powdery mildew (GPM) in a small spraying experiment on two Vitis vinifera L. cultivars (Chardonnay and Kékfrankos) with different susceptibility to Erysiphe necator. The visual symptoms of GPM on leaves and clusters were examined at three phenological states. The harvest yield was characterized by two methods, data were analyzed with one-way ANOVA and Tukey post-hoc test. Regular fungicide treatment (CT) and its combinations with PFO showed better results in both varieties to repress GPM in 2015 relative to sole PFO treatments. Mean values of combined treatments were often lower than CT but did not differ significantly from each other. The same was observed in 2016, despite the higher pressure of GPM, and missed the third survey. No significant differences were detected between treatments in yield. In contrast, the mean cluster weight of CT and combined treatments resulted in (insignificantly) higher values in each variety and year. In summary, the sole PFO showed some disease control capability as reported earlier, but this effect was greatly affected by the given vintage. Combining PFO with CT resulted in increased protection against GPM relative to the solely applied fungicides. However, this effect was not significant in all cases. It also depended on the vintage and cultivar characteristics. The beneficial impact of paraffin oil as an additive to CT may be due to the induction of plant stress responses and/or its ability to support the adherence and absorption of the combined agents.
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Effect of anthocyanin-rich sour cherry extract on the level of IL-8 in LPS-induced endothelial cell
27-30Views:235The anthocyanin content of the Hungarian sour cherry is remarkable. Nutraceutical and pharmaceutical effects of the anthocyanins and their role in disease prevention have been studied extensively. Endothelial cells are involved in the pathogenesis of several inflammatory diseases. The objective of this work was to investigate pure sour cherry extract on human umbilical cord vein endothelial cells (HUVECs) as an inflammatory model. HUVECs were treated with 100 ng/mL lipopolysaccharide (LPS) and 50 mg/mL sour cherry extract or M199 medium as control. The optimal concentration range of the sour cherry extract was investigated and selected based on MTT assay measuring the conversion of the tetrazolium salt to formazan by mitochondrial dehydrogenases. The level of interleukine-8 (IL-8), a pro-inflammatory cytokine, was measured in Luminex MagPlex assay. LPS treatment significantly increased the secretion of IL-8. The pure sour cherry extract was able to attenuate this increment indicating the potent anti-inflammatory effect of pure sour cherry extract. Our results emphasize that pure sour cherry extract could reduce the LPS-induced inflammatory response thereby may improve endothelial dysfunction.
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Analysis of the plant physiological effects of late, artificial corn smut infestation using remote sensing methods
31-35Views:177In Hungary, corn is also infected by several important pathogens. In this experiment, we analysed the plant physiological effects of artificial late cron smut infestation using remote sensing methods under field conditions We examined the experimental area from which the data comes from with a DJI Phantom 4 Multispectral Drone NDVI and NDRE indices were calculated and analyzed in GIS programs. Individuals treated with a higher dose remained much greener than the untreated control. They also showed significant differences within the indices used.
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Distribution and damage of bacterial canker on lemon bushes in the conditions of the Southern part of Azerbaijan
41-49Views:133This paper summarises and presents the results of two-year (2020–2021) field and laboratory studies on the spread and harmfulness of bacterial canker of citrus crops (Xanthomonas citri (Hasse) Dowson.) on mid-ripening lemon cultivars (Citrus limon L.). Experimental field research conducted by us in 2020–2021. It has been established that bacterial canker (Xanthomonas citri) is found mainly on lemon bushes (Citrus limon L.). The pathogen also causes canker (Xanthomonas citri) on kinkans (Fortunella margarita (Lour) Swingle.), poncirus (Poncirus (L.) Raf.), lime (Cirtus aurantiifolia (Christm.) Swingle.). Japanese cultivars of oranges (Citrus sinensis (L.) Osbeck.) and citron (Citrus medica L.) are distinguished by significant tolerance. The most resistant are tangerines (Cirtus reticulata Blanco.) – they are almost not affected by bacterial canker (Xanthomonas citri).
We have established environmental factors that contribute to the wide spread and development of bacterial canker (Xanthomonas citri) on lemon bushes in the southern part of Azerbaijan.
The main indicators of the harmfulness of bacterial canker (Xanthomonas citri) have been identified. The potential for the death of canker-infected lemon fruits has been established. The characteristic features of external and internal signs of the disease were established. A scheme for combating bacterial canker (Xanthomonas citri) has been developed, and the optimal concentration of fungicides that retard the growth and development of pathogens has also been established. Photographs of bacterial canker (Xanthomonas citri) damage to lemon fruits are presented.
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The Role of Trichoderma in the Rhizosphere of Tomato Plants
67-69Views:73It is well established that microorganisms are closely associated with the roots of plants can directly influence plant growth and development. Species of Trichoderma, on the other hand are primarily studied for their ability to control plant disease. The ability of species of Trichoderma to directly promote or inhibit plant growth has been noted for many years.
Tomatoes were treated with different Trichoderma strains by seed treatment and soil inoculation. The Trichoderma were grown on malt-agar medium and conidia were washed off by sterile water for making suspension which contained 107 CFU/ml (colony forming unit/ml). The suspension was used for seed treatment and for the soil inoculation by watering as well. The artificial soil inoculation was made by Trichodermas growing on grounded maize were mixed in mould and tomato seed were sown in it. Tomato seeds were also sown in bags made of close-meshed material which allowed the soil microorganisms to colonize the roots but it simultaneously protected the roots from soil contamination. Roots were put on Trichoderma selective medium to check the root colonization of the Trichoderma.
The tomato plants were bedded out in a field in four repetition. After harvesting by hand the results supported by statistics shown that there was significant differences between the yield of the untreated and treated tomato plants by Trichoderma strains. -
Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
45-51Views:115In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harvested. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials.
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Increase of Wheat (Triticum aestivum L.) Resistance to Leaf Rust (Puccinia tritici) via Gene Transformation
127-129Views:81Leaf rust is one of the most significant fungal disease of wheat not only in Hungary but also in other parts of the world. For improving leaf rust resistance of winter wheat variety (Hajdúság, 2003) produced by conventional breeding methods, verified by results of variety tests, showing outstanding results in the aspect of the most important economic values, integration of tissue culture technics, genetic engineering and traditional
methods may provide facilities. Building the gene(s) responsible for resistance into the determined genome can improve the resistance in a way that changes other features of the plant slightly or not at all. In the course of genetical transformation of the variety Hajdúság we applied one of the wheat’s own effecient green-tissue specific insurer genetical regulator, the promoter of ribulose carboxylase 1-5 bisphosphate (RuBisCo) ‘s small
subunit to control the expression of the gene cmg1.