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  • Phytoplasma infection status survey in plum psyllid (Cacopsylla pruni) population
    45-48
    Views:
    164

    European Stone Fruit Yellows (ESFY) phytoplasma disease causes an increasing amount of damage. This is especially true to the Gönci growing region. The insect vector of the disease, which has been shown to have a vector role during transmission experiments, is the plum psyllid (Cacopsylla pruni). In 2018, during the swarming period of plum psyllid, in 3 different settlements (Boldogkőváralja, Nagyvárad and Bekecs) 265 psyllidswere collected, from which 165 were plum psyllid. Molecular biology studies showed 106 individuals infected with phytoplasma, of which 20 were males and 86 were females.

  • Effect of two different cropyear and the agrotechnological factors on the agronomic characteristic of the winter weat in a lon-term experiment
    143-149
    Views:
    147

    We 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%). 

  • Examination of the plum psyllid (Cacopsylla pruni Scopoli), a vector of European Stone Fruit Yellows (ESFY) phytoplasma in the countryside of Boldogkőváralja (Hungary)
    5-11
    Views:
    243

    European Stone Fruit Yellows(ESFY) phytoplasma disease on apricot was identified by molecular methods for the first time in 1992 in Hungary. Currently, the pathogen is known as’ Ca. Phytoplasma prunorum’. Since, the pathogen become wide-spreaded and manyof the apricot-plantations had to be eliminated. In 2009 and 2010 in the countryside of Boldogkőváralja the infection of the apricot-plantations was about 77%. As the disease spreading and causing large damages, we studied the roleo fpossible vector,the plum psyllid (Cacopsylla pruni Scopoli) in the areas of Boldogkőváralja, North-East-Hungary. Studies were done in the year of 2016, monitoring the behaviour of the psyllids in four different areas, and caught 41 them for further examination. We collected plant samples from those apricot trees, on which the plum psyllids were caught.

  • Examination of the presence and effect of udder edema in Holstein-Friesian cattle
    125-130
    Views:
    193

    Mastitis is the most common disease of dairy cows and the most expensive in terms of treatment. For this reason, great emphasis must be placed on its prevention. Based on literature sources, it can be said that there is a positive correlation between the prevalence of udder edema and the occurrence of mastitis. Our studies were carried out in a dairy farm in Csongrád-Csanád county. So far we have collected data from 64 cows with udder edema. The severity of udder edema was evaluated on a scale of 0–3 points one week before calving and for 3 weeks after calving. We observed that udder edema occurred in 78% of the studied cows at the time of the first calving. After calving, the length and diameter of the four udder teats were examined. Both anterior and posterior teats were shortened in severely edematous cows. When examining the diameter of the teat, we found that, depending on the severity of the edema, the anterior and posterior udder teats were 2.5 and 1.6 and 1.6 and 1.5 mm thicker respectively than those of cows without edema.

  • Laboratory diagnoses of the isolates of chestnut blight disease fungus Cryphonectria parasitica (MURR. BARR)
    45-52
    Views:
    124

    Chryphonectria parasitica, the casual agent of chestnut blight, is one of the most important fungal pathogens of chestnut (Castanea spp.) in Europe and Hungary. In this study, we analyzed the ITS region of five Cryphonectria parasitica strains isolated from different location of Hungary. The differences among the Cryphonectria parasitica isolates were not insignificant because only two sites were considered as informative for the parsimony analysis. As the differences among geographically different isolates were insignificant, we mean that the evolutionary distance by ITS sequences within Hungarian Cryphonectria parasitica isolates is too small to get well based consequences for the phylogenetic relationships.

  • Biological control of sweet chestnut on Pécsbánya, Hungary
    77-81
    Views:
    268

    The 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.

  • Testing disease resistance in autumn wheat genotypes by means of field experiments
    30-40
    Views:
    122

    According to our scientific results we can state that we have to use integrated pesticides management in crop protection against the diseases of winter wheat. One of the most important elements of IPM is to select a genotype characterised by good resistance to diseases (and by high yield ability and excellent baking quality). It is especially important that the wheat variety have tolerance against not only to one or two leaf and spike (grain) diseases, but „complex” tolerance. It is not necessary to give up the growing of a variety which has susceptibility to different diseases because we can protect it using appropriate chemical management. In the intensive growing stage of wheat (BBCH 32-37) we can use a noncompulsary fungicide-treatment (depending on e. g. the infection, ecological conditions) and, at the beginning of the flowering stage
    (BBCH 59-65), we have to use a compulsary fungicide-treatment (in spite of e. g. special weather conditions, resistance genotype)to ensure high yield and good quality.

  • Study of animal welfare status in dairy cow herds in Hungary – looking for causes of lameness
    47-50
    Views:
    206

    In the last 20–30 years lameness in cattle was found to be third the most influential disease next to mastitis and reproduction disorders. Studies have been established to explore reasons for lameness and prevention. The problem with more robust prevention plans is that knowledge and research evidence is not strong enough to run an effective prevention plan. The aim of the research is to look for reasons of lameness by observing number of cows on 6 farms during 2 lactations. Performance data will be put together to body condition score (BCS) and lameness scores. Other examination is focused on monitoring of 40 farms. This part of the project is more related to extension, collecting and sharing solutions for decreasing lameness. Producers are advised what kind of measures are possible to reduce occurrence of lameness. Effectiveness of those actions will be measured at the end of the study. The first preliminary results show lack in almost all preventive measures needed to be taken in minimising lameness. Those areas are related to poor facilities, lack of straw, problems with labour and basic management.

  • Effect of anthocyanin-rich sour cherry extract on the level of IL-8 in LPS-induced endothelial cell
    27-30
    Views:
    242

    The 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.

  • Study of animal welfare status in dairy cow herds in Hungary – looking for causes of lameness
    25-29
    Views:
    151

    In the last 20-30 years, lameness in cattle was found to be third the most influential disease next to mastitis and reproduction disorders. Studies have been established to explore reasons for lameness and prevention. The problem with more robust prevention plans is that knowledge and research evidence is not strong enough to run an effective prevention plan. The aim of the research is to look for reasons of lameness by observing number of cows on 6 farms during 2 lactations. Performance data will be put together to body condition score (BCS) and lameness scores. Other examination is focused on monitoring of 40 farms. This part of the project is more related to extension, collecting and sharing solutions for decreasing lameness. Producers are advised what kind of measures are possible to reduce occurrence of lameness. Effectiveness of those actions will be measured at the end of the study. The first preliminary results show lack in almost all preventive measures needed to be taken in minimizing lameness. Those areas are related to poor facilities, lack of straw, problems with labor and basic management.

  • Analysis of the plant physiological effects of late, artificial corn smut infestation using remote sensing methods
    31-35
    Views:
    186

    In 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.

  • Susceptibility of stem infected sweet corn hybrids to common smut disease
    55-57
    Views:
    435

    The 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.

  • Food allergy, safety and analytics
    323-326
    Views:
    132

    The food allergy is a hypersensitivity reaction against naturally occurring proteins in food. These types of disease can cause not only personal inconvenience to the patient but serious health, food safety and food analysis, social-economic problems. The only effective treatment for these illnesses is a life-long diet avoiding the allergenic foods or components of food. In the interest of the patients’ health 14 allergenic components must be labeled on the food packaging. To meet the requirement of regulation reliable and valid analytical methods are necessary which for the most allergenic foods are not available.

  • The role of type traits of dairy cattles in long productive life
    11-18
    Views:
    132

    In the last few decades, a new intensive milking stock has developed as a result of breed-converter crossing in Hungary. Additionally, the reproduction biology of the population was adversely affected by keeping and feeding technologies. Productive lifetime has shortened and the service period has lengthened. However, profitable milk production requires cows with longer productive lives and larger life-time productions. In our study, we made a comparison between production, culling causes, and type traits of culled Holstein Friesian cows after first calving and of cows with a minimum of eight lactations. We established that the first lactation production of cows with longer productive lives was more or less homogeneous. Disease of metabolism as well as digestive and respiratory problems, were the main causes of the culling of cows with short productive lives, and reproduction and udder problems as well as low production, were the main causes of the culling of cows with long productive lives. We found a significant difference in the distributions of strength, body depth, dairy form, croup width, rear leg side view, foot angle, fore udder attachment and teat placement between the two groups. Furthermore, we established that cows with lower stature, less strength, a somewhat deeper body, better dairy form, narrower croup width, smaller foot angle, looser fore udder attachment and some outside teat placement had longer productive lives.

  • Management of phytopathogens by application of green nanobiotechnology: Emerging trends and challenges
    15-22
    Views:
    334

    Nanotechnology is highly interdisciplinary and important research area in modern science. The use of nanomaterials offer major advantages due to their unique size, shape and significantly improved physical, chemical, biological and antimicrobial properties. Physicochemical and antimicrobial properties of metal nanoparticles have received much attention of researchers. There are different methods i.e. chemical, physical and biological for synthesis of nanoparticles. Chemical and physical methods have some limitations, and therefore, biological methods are needed to develop environment-friendly synthesis of nanoparticles. Moreover, biological method for the production of nanoparticles is simpler than chemical method as biological agents secrete large amount of enzymes, which reduce metals and can be responsible for the synthesis and capping on nanoparticles.

    Biological systems for nanoparticle synthesis include plants, fungi, bacteria, yeasts, and actinomycetes. Many plant species including Opuntia ficus-indica, Azardirachta indica, Lawsonia inermis, Triticum aestivum, Hydrilla verticillata, Citrus medica, Catharanthus roseus, Avena sativa, etc., bacteria, such as Bacillus subtilis, Sulfate-Reducing Bacteria, Pseudomonas stutzeri, Lactobacillus sp., Klebsiella aerogenes, Torulopsis sp., and fungi, like Fusarium spp. Aspergillus spp., Verticillium spp., Saccharomyces cerevisae MKY3, Phoma spp. etc. have been exploited for the synthesis of different nanoparticles. Among all biological systems, fungi have been found to be more efficient system for synthesis of metal nanoparticles as they are easy to grow, produce more biomass and secret many enzymes. We proposed the term myconanotechnology (myco = fungi, nanotechnology = the creation and exploitation of materials in the size range of 1–100 nm). Myconanotechnology is the interface between mycology and nanotechnology, and is an exciting new applied interdisciplinary science that may have considerable potential, partly due to the wide range and diversity of fungi.

    Nanotechnology is the promising tool to improve agricultural productivity though delivery of genes and drug molecules to target sites at cellular levels, genetic improvement, and nano-array based gene-technologies for gene expressions in plants and also use of nanoparticles-based gene transfer for breeding of varieties resistant to different pathogens and pests. The nanoparticles like copper (Cu), silver (Ag), titanium (Ti) and chitosan have shown their potential as novel antimicrobials for the management of pathogenic microorganisms affecting agricultural crops. Different experiments confirmed that fungal hyphae and conidial germination of pathogenic fungi are significantly inhibited by copper nanoparticles. The nanotechnologies can be used for the disease detection and also for its management. The progress in development of nano-herbicides, nano-fungicides and nano-pesticides will open up new avenues in the field of management of plant pathogens. The use of different nanoparticles in agriculture will increase productivity of crop. It is the necessity of time to use nanotechnology in agriculture with extensive experimental trials. However, there are challenges particularly the toxicity, which is not a big issue as compared to fungicides and pesticides.

  • Flesh firmness examination of scab-resistant apple varieties in a storage experiment
    93-98
    Views:
    149

    Of the different physical characteristics of fruits, one of the most essential qualities is flesh firmness, as is an important parameter when selling fresh apples, processing the fruit (processing industry) and during its storage. In the scope of our research, we examined five apple varieties originating from the Derecske horticultural site of KITE cPlc. in 2016. The plantation was planted to be suitable for intensive apple production. Samples were collected at the time of maturity (August-October) of the given variety. The five examined apple varieties (Gaia, Isaaq, Modí, Smeralda and Fujion) are all resistant to apple scab (fungal disease caused by Venturia inaequalis). The two-month storage experiment was conducted at 16-17 °C, which had an aggressive effect on our stored apples. Flesh firmness, weight and diameter were measured on three dates for each of the five apple varieties. Our results were evaluated using IBM SPSS Statistics 20 software. We aimed to compare flesh firmness, weight and diameter of the five apple varieties and their changes during storage. Isaaq (86.34 N/cm2), Modí (94.06 N/cm2) and Fujion (84.90 N/cm2) had outstanding initial flesh firmness results. The Modí apple variety provided the best storage parameters.

  • An unusual occurrence of Taphrina deformans on apricot trees in Hungary
    86-92
    Views:
    146

    In 2011 a very rare occurence of leaf curl (leaf blaster) disease symptoms of apricot (pathogen: Taphrina deformans) was observed in different apricot plantations in Eastern-Hungary (Debrecen-Józsa, Hajdú-Bihar county) and Northern-Hungary (Bekecs district, Borsod-Abaúj-Zemplén county). The pathogen is common on peach and nectarine resulting serious symptomps and considerable damages in almost every year, although in this year infections of peaches were very low close to the locations. Although there are some references that apricot and even almond are hosts of the fungus but in Hungarian circumstances the infestation on apricot counts unique and rare. Observations were made on symptoms, microscopic photos and measures were taken on exoasci, ascospores and blastospores, respectively. As far as we know this is the first description of Taphrina deformans fungus on apricot in Hungary.

  • Distribution and damage of bacterial canker on lemon bushes in the conditions of the Southern part of Azerbaijan
    41-49
    Views:
    136

    This 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.

  • Inland and foreign Erwinia amylovora isolates by carbohydrate utilization
    29-33
    Views:
    90

    Fire blight, a plant disease caused by the bacterium Erwinia amylovora, produces serious losses in apple and pear orchards all over the world. Since the appearance of fire blight in Hungary (Hevesi, 1996) Erwinia amylovora isolates were collected in different years, from different hosts and areas in order to establish gene bank for future epidemiological studies. We had isolates from foreign countries as well. The aim of our research was to compare all of the Hungarian and foreign isolates by carbohydrate utilization. 
    In our experiments effect of carbohydrates on E. amylovora multiplication was determined using API 50 CH strip (bioMérieux, France). By the API 50 CH strip method we checked a number of unstudied carbohydrates. The results of the tests shows colour changes. Based on utilization of 49 carbohydrates of API 50 CH kit by E. amylovora isolates, two groups of carbohydrates can be defined: “Utilized” - and “Not utilized”  carbohydrates. All isolates utilized 20 different carbohydrates after 164 hour incubation. Conversely, isolates also could be divided into four groups (1, 2, 3, 4) by arbutin and raffinose utilization. In group 1.-isolates utilize arbutin; 2.- utilize raffinose; 3.- utilize both arbutin and raffinose; 4. -utilize neither arbutin nor raffinose. Presumably carbohydrate content of nectar could play an important role on invasion of the (E. amylovora) bacterium via flower.
    It could be concluded that the carbohydrate utilization – completed with genetic analysis – can be used for characterization of Erwinia amylovora isolates.

  • The Effect of Plant Density on the Yield of Sunflower Hybrid’s in 2001-2002
    184-189
    Views:
    126

    Nowadays, for increasing efficiency of sunflower production treating hybrid-specific technologies was required. Increasing of hybrid choice gave reasons for trials in respects of critical factors, as well as in case of genotype-enviroment interactions. The effect of changing plant density show up as determinant factor which affects on yield as well as on plant hygienic conditions. Trials were established on calcareous chernozem soil (Hajdú-Bihar county), in 2001-2002. The field trials were randomized, in four repetition on small parcels. The plant density trials were established in 35.000-75.000 plant/hectar interval using a scale of 10.000 plant/hectar. 10 hybrids were used in both year.
    In 2001, 55.000 plant/hectar density was the optimal, in case of most of the hybrids. The yield of tested hybrids did not show significant difference. Yield decreasing effect of using less than optimal density was more significant than in case of using optimal plant density. In 2002, the optimal density was in 45.000-65.000 plant/hectar interval, there was no possibility to find narrower optimum.
    Presence of Diaporthe helianthi and the damage caused by the pathogen was significant in 1997-1999, whereas in 2001-2002 the large-scale appearance of the pathogen did not occur. In 2001, the affect of high plant density on disease caused by Diaporthe helianthi showed just tendency-like appearance, in 2002, the infection showed up just in the end of the vegetation period, without significant damage. In spite of the low infection level, the difference between the infection of the diverse plant density treatment was significant. Increasing plant density made increase the frequency of the Diaporthe helianthi infection. The rate of the flower diseases was around 3-16% in 2001, the highest infection level emerged in 65.000-75.000 plant/hectar density, whereas in 2002, the rate of infection level was less than 10%. The increasing plant density helped the development of flower diseases.

  • Examination of feral pigeon populations at animal breeding farms
    52-56
    Views:
    140

    In the course of our examination, we assessed biometric data that determine gender, we evaluated sexual activity, measured the nourishment and necropsies of two feral pigeon populations feeding and nesting at animal breeding farms. The changes in the body weight of the different genders were significant on both farms (p<0.05).
    The body weight and the crop volume of the birds were not significantly different at the examined farms.
    On both farms, the elemental food source of the birds was the fodder and corn kernels given to cattle, and was supplemented by that of the pigeons living at the Debrecen farm with food from surrounding farms and with other seeds (pea, millet, rye).
    By the examination of the genitals, the birds collected from the Nyírbátor farm showed sexual activity from the beginning of spring, and in the summertime decreasing activity is characteristic, while the pigeons from the Debrecen farm are only active from the summer months. In the course of the examinations in the Veterinary Institute of Debrecen, the birds proved to be free of parasites and the results of the Newcastle disease analysis were negative as well. The bacteriologic analyses showed a different proportion of E.coli, Pasteurella multicoda, haemolysing Staphylococcus bacteria at the two cattle farms. During the examinations for the statement of Salmonellas, this causative agent was stated only in case of birds that spend nights and nested in the town, which allude to human origin. We demonstrated Eimeria oocysts during the parasitological examination of the fecal samples in 5 cases at the Debrecen, and in 1 case at the Nyírbátor farm.

  • Sorghum and millet as alternative grains in nutrition
    91-95
    Views:
    280

    Sorghum (Sorghum bicolor L.) and millet (Panicum miliaceum L.) are the fifth and sixth most important cereal crops in the world. Gluten-free grains, therefore persons with coeliac disease could consume them also. In addition, they have a lot of positive effects due to their phenolic compounds (phenol acid, flavonoid, tannin). The total phenol content of sorghum is high, but Panicum miliaceum and Eleusine coracana have higher antioxidant activity. Fiber and mineral contents are also high, the protein contents are also higher than in standard cereals. Sorghum use is similar to corn: starch, glucose, syrup, and oil can be produced. Moreover, it can be used in preparing whole grain products, bread, pancake, dumpling, mush, cake, pasta and beer from sorghum. Broom and forage are also can be prepeared from them. Millet used such as mush, steamed food, cake, bread, alcoholic and non-alcoholic beverages.

  • Comparison of Integrated and Conventional Production of Young Nonbearing Apple Orchards
    3-5
    Views:
    90

    The large number of pesticide applications in apple orchards creates serious problems with pesticide residues and their side effects on beneficial organisms, the environment and human health. This is the reason behind the search for new systems for apple protection.
    The investigations were made in apple orchards of the Institute of Agriculture at Kyustendil, during the period from 1997-1999. Three scab resistant cultivars grafted on rootstocks MM106 were planted in 1996. The orchard was divided into four plots. Two plots were treated as „conventionally” and the other two were treated as „integrated” according to the general principles, rules and standards of integrated apple production.
    The key disease during the experimental period was powdery mildew, which can be controlled only with pruning of infected clusters and shoots during the first three years after planting. The key pests in the orchard during the nonbearing period were the green apple aphid and San Jose scale. In the integrated plant protection system, it is possible to reduce the number of insecticide treatments depending on the density of the main pests.

  • Seed biology and possibility of improvement of seed germination capacity on Virginia mallow (Sida hermaphrodita L. Rusby)
    71-76
    Views:
    159

    Sida hermephrodita or Virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through the last two decades. Additionally, the plants have a lot of uses and benefits for instance it can use as a fodder crop, honey crop, ornamental plant in public gardens. It has favourable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in the beginning phase of domestication therefore it has a serious disadvantage: the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seeds/acre instead of 10–20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a available, basically wild Sida population. In the first stage of our experiments we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65 oC, 80 oC, 90 oC), from 29,3% to 46% germinated from those samples which were collected from the population of Sida hermaphrodita in Debrecen. The average germination for all season was 5–10% without treatment and rinsed using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46%) after the hot water operation in spite of the previous studies. We discovered that apparently there are close relationship between the seed fresh weight or water uptake capability and the percentage of infection. Following these recognition we modified our technique,in such a way that we fractionated the seeds based on their fresh weight/or relative density before we carried out the treatment. When we filtered the floating seeds on the surface of water, the hot water treatment was performed considerably better on the sunk seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination).

  • Examination of the efficacy of different fungicides against Macrophomina phaseolina and Sclerotinia sclerotiorum in laboratory conditions
    21-24
    Views:
    271

    Macrophomina phaseolina and Sclerotinia sclerotiorum are two significant fungal pathogens of sunflower. M. phaseolina causes charcoal rot and ashy stem blight in several important crop species. Sclerotinia sclerotiorum causes white mold disease which can occur as middle stalk rot, head rot and premature plant death. Due to the wide host range of the two pathogens and their survival structures, crop rotation cannot provide sufficient protection against them. In our experiment, we selected two fungicides, Mirage and Prosaro, which are widely used in practice, and we tested their efficacy against the two pathogens. The efficiency of these fungicides was tested at a concentration of 10; 20; 50; 100 and 500 ppm. The Prosaro totally inhibited the mycelial growth of both pathogens at a concentration of 50 ppm, 100 ppm and 500 ppm. The Mirage caused total mycelial growth inhibition in all treatments against both pathogens.