Search
Search Results
-
Testing of paraffin oil efficiency against grape powdery mildew in Eger wine region
73-80Views:362The aim of the present study was to examine the efficiency of paraffin oil against powdery mildew in Eger wine region. The experiment has been carried out in 2013 and 2014 with Chardonnay and Kékfrankos grape varieties, which have different resistance against powdery mildew. The effectiveness of the oil was examined on leaves and clusters (frequency and intensity). This oil was effective against Erysiphe necator infection on field trials in Chile and Brazil. The spread of downy mildew (Plasmopara viticola) was also inhibited by this material in some experiments conducted in Spain and France.
The differences between oil treatments represented the sensitivity of the grape varieties in accordance with the applied dosages. The oil was effective against powdery mildew with different extent as a result of the so called ”vintage effect”. In 2013, the treatment of the highest dosage (D3) didn’t differed significantly in frequency and intensity of infection from the regular treatment (clusters of Kékfrankos, leaves of Chardonnay). In 2014, the oil was not so effective against powdery mildew compared to 2013. No remarkable differences were detected between the treatments due to the strong pressure of powdery mildew. Furthermore, no any effect of the lowest dosage (D1) was detected in the case of the sensitive clusters of Chardonnay and leaves of Kékfrankos in both experimental years.
In summary, the oil treatment has an effect against powdery mildew, however this efficiency largely depends on the vintage characteristics and the pressure of powdery mildew. Further investigations are neccessary, for example field trials with combinations of other sprays. The oil can be useable as fungicide with proper care in eco-friendly integrated and bio (ecological) viticulture.
-
Selection of powdery mildew resistant and susceptible grapevine genotypes with molecular markers
100-104Views:108Incorporation of competitive quality and resistance against the most important fungal diseases (powdery and downy mildew) in a cultivar is one of the most important aims of grapevine breeding. In the 20th century, the most advanced results in grapevine resistance breeding were achieved by French researchers. They used resistant cultivars in more than 30% of their growing areas. In these varieties, North American wild Vitis
species were the resistance gene sources. The discovery of immunity-like resistance of Muscadinia rotundifolia opened new perspectives in resistance breeding. M. rotundifolia harbours a dominant powdery mildew gene, providing resistance in highquality cultivars after back-crosses with V. vinifera varieties. M. rotundifolia has been involved in the Hungarian grape breeding programs since 1996, thanks to a French-Hungarian variety exchange. In addition to traditional selection methods, application of MAS (Marker Assisted Selection) based on various types of
molecular markers, can provide additional tools for these efforts. Run1 locus, responsible for powdery mildew resistance, was identified in Muscadinia rotundifolia. Molecular markers closely linked to this locus are very significant in screening progenies deriving from M. rotundifolia and V. vinifera crosses, making possible the discrimination between resistant and susceptible genotypes at DNA level. In our analyses BC5 progeny of {(M. rotundifola×V. vinifera) BC4}×Cardinal (V. vinifera) tested for powdery symptoms were analysed with PCR-RFLP (GLP1- 12P1P3) and microsatellite markers (VMC4f3.1, VMC8g9). Our results proved the applicability of the linked markers and reliability of marker assisted selection. -
The Effect of Forecrop and Plant Protection on the Pathology Parameters and Yields of Winter Wheat
84-89Views:88We carried out our experiment in the cropyears of 2000/2001, 2001/2002 and 2002/2003, on calcareous chernozem soil, at the experimental site of the Debrecen University Farm and Regional Research Institute, at Látókép. We examined the disease resistance and the yield quantity of Mv Magvas variety by adopting different forecrops and plant protection technologies, at 30+30 N level and at normal cereal row spacing. We applied two forecrops (wheat and pea) and two plant protection technologies (extensive and intensive). We measured the rate of infection by population survey in the first ten days of June.
In the course of our examinations, we found, that the rate of powdery mildew infection was higher in the thicker population sown after pea forecrop in all three years, as powdery mildew is not a typical cereal disease.
The infection rate of leaf mildew and DTR (Dreschlera tritici-repentis) was higher after wheat forecrop in all examined years, because these are typical wheat diseases and infection centres in the soil promote the spreading of these diseases. However, it was possible to parry the adverse effect of forecrops by intensive plant protection.
Due to the chernozem soil, wich has good water management features, and due to the good preparation of the seedbed, the effect of forecrops on yield quantity did not appear in the examined years. The quantity of the yield was only slightly larger after pea forecrop in the cropyears of 2000/2001 and 2002/2003 than after wheat. Nonetheless, the data of technical literatures state that the yield quantity can be larger, even by 15-20%, after pea forecrop.
In the course of intensive plant protection technology, we applied systemic pesticides, while in the course of environmentally sound technology, we used contact pesticides of sulphur content. In those populations that were treated with environmentally sound plant protection technology, infection rate was higher in all three years.
Yield quantities were somewhat lower in the course of applying extensive, environmentally sound technology, because diseases appeared in these populations to the higher degree. Powdery mildew does not, but leaf mildew and Dreschlera tritici-repentis have a significant yield decreasing effect. With appropriate, well-selected fungicides, we were able to keep every leaf diseases well in hand, and the rate of infection was almost independent of the influence of the breeding year. -
Study of plant production modells with different intensity in winter wheat production
51-60Views:91The effects of crop rotation, nutrient supply and plant protection technologies were examined on the yield of Mv PÁLMA winter wheat variety and on the most important diseases of ear and leaf. Our experiments were carried out on chernozem soil in the Hajdúság in 2006 and 2007, and three plant protection technologies (extensive, average, intensive) and three irrigation variations (without irrigation, irrigated with 50 mm, irrigated with
100 mm) were applied in different crop rotation systems.
In the triculture crop rotation a higher rate of infection was observed than in the biculture crop rotation, because the vegetative growth was more expressed after pea and these microclimatic factors were favourable for the development of pathogens.
In the triculture crop rotation (pea – wheat – maize) the powdery mildew, DTR and leaf rust of wheat were present in both examined years (powdery mildew 5-15%, DTR 14-42%, leaf rust 8-37% in cropyear 2005/2006, powdery mildew 12-32%, DTR 9-29%, leaf rust 8-26% in cropyear 2006/2007). Fusaria could be observed in 2006 (depending on the plant protection technologies and nutrient supply in the biculture 7-27% and in the
triculture 5-19%). With higher amounts of fertilizers the rate of infection increased and reached its maximum at the highest dose of nutrient supply (N200 +PK).
We observed the highest rate of infection by ear and leaf diseases in the case of the extensive technology, while this rate could be considerably reduced by the application of the intensive technology.
Both in 2006 and 2007, yields were the highest at the N100-200+PK levels in the triculture after pea (6028-7939 kg ha-1 in cropyear 2006, 6578-8690 kg ha-1 in cropyear 2007 depending on plant protection technologies), and at the N150-200+PK levels in the biculture after maize (6096-7653 kg ha-1 in cropyear 2006, 4974-8123 kg ha-1 in cropyear 2007 depending on the plant protection technologies). The highest yield maximums were
reached when pea was the forecrop. The yields on the experimental plots of the intensive plant protection technology was 224-2198 kg ha-1 higher (depending on the forecrop) compared to the plots where the extensive technology was used.
The highest yield without irrigation was at the N150+PK both in biculture and triculture crop rotation. Among the irrigated variations Ö2 and Ö3 at N200+PK fertilisation resulted in the highest yield in the biculture crop rotation, while the N100+PK level in triculture system. In the biculture crop rotation the extra yield was 14-51% higher (575-1225 kg ha-1 depending on plant protection technology) when 50 mm water was irrigated, and
15-54% higher (778-2480 kg ha-1) if 100 mm irrigation was applied comparing to the non-irrigated versions. The yield was 7-17% higher (560-1086 kg ha-1) in the Ö2 irrigation variation, and 8-23% (691-1446 kg ha-1) higher in the Ö3 irrigation variation compared to Ö1 irrigation variation (non-irrigated).
A correlation analysis was made to reveal the connection between the yield, the amount of fertilizers, the rate of infection, the plant protection technologies and the forecrops. Strong positive correlation (0.846) was found between year and fusaria infection. Strong positive correlation was observed between fertilization and powdery mildew infection (0.525), fertilization and DTR (0.528), fertilization and yield quantity (0.683). Lower
correlation was found between fertilization and leaf rust infection (0.409), and forecrop and yield (0.472), recpectively. Negative correlation was calcutated between plant protection technologies and DTR (-0.611), and plant protection technologies and leaf rust (-0.649). -
Preliminary test: Evaluation and selection of tomato (Lycopersicon esculentum Mill.) varieties resistant to drought and powdery mildew
33-37Views:117Powdery mildew (Leveillula taurica) and (Oidium neolycopersici) are two harmful fungi that invade the tomato (Lycopersicon esculentum Mill.) plant and grow in dry conditions. Under the influence of polyethylene glycol 6000 at a concentration of 12%, the total seedlings fresh weight, total seedlings dry weight, seedling growth rate of one seedling, seedling length, and tissue water content percentage for three tomato varieties were assessed. Despite the superiority of the (Mobil) tomato variety in terms of numerical values, the results revealed no significant differences between varieties. As a result, (Mobil) has greater vigor under environmental drought stress of lower osmotic stress than other tomato varieties. More work is required to evaluate the research selection of varieties resistant to biotic stresses in dry areas, such as powdery mildew disease.
-
Effect of two different cropyear and the agrotechnological factors on the agronomic characteristic of the winter weat in a lon-term experiment
143-149Views:109We 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:111We 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.
-
The effect of reduced sprinkler programs on the main fungal pathogens of apple in environmentally sound production systems
13-16Views:75Aim of our two-year study was to evaluate the possibilities of chemical use against key fungal pathogens (apple scab, apple powdery mildew and brown rot) in integrated and organic apple production. Therefore, first, disease incidence was compared in standard and reduced spray programmes and then each technological variation was evaluated from practical point of view. Altogether four spray programmes were compared. Standard and reduced spray programmes were performed in the integrated production. The same pesticides were used in the reduced spray
programme compared to standard one but numbers of spray were reduced by 25% at the second half of the season. Standard and reduced spray programmes were also performed in the organic production and the numbers of spray were reduced by 40% in the reduced spray programme. Incidence of diseases was low in both standard and reduced spray programmes in integrated production. Diseases level was high in the organic production and disease increased significantly in the reduced spray programmes compared to standard programmes. Results showed that reduction in spray numbers at the second half of the season can be used practically in integrated production. Omission of sprays in organic
production resulted in serious disease management risk; therefore, it is not recommended for practical use. -
Spectral analysis of stress symptoms caused by apple powdery mildew (Podosphaera leucotricha
83-88Views:157An orchard can be examined on the basis of spectral data, using methods with which the reflected radiation can be divided into a large number of (several hundreds) small spectral channel (some nm). Calculated on the basis of such hyperspectral data from different index numbers the water supply of foliage conditions can be well characterized.
The research site is an intensive apple orchard, which located in University of Debrecen, Agricultural Sciences Centre, Farm and Regional Research Institute at Pallag. During my experiments the preliminary evaluation of spectral, non-invasive measurement method are carried out for detecting stress symptoms caused by Podosphaera leucotricha.
Based on the results narrow band greenness indices (NDVI705, mNDVI705, mSR705 and REP) can be used for determination of diseased canopy and for the detection of stress symptoms of Podosphaera leucotricha,. These statements can be utilized in precision plant protection systems, since it can be a basis for such integrated active sensors with LED or laser light source, measuring reflectance at the certain spectral range, which can facilitate real time status assessment of orchards and can control precision fungicide utilization.
-
Comparison of Integrated and Conventional Production of Young Nonbearing Apple Orchards
3-5Views:76The 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. -
The effects of agrotechnological factors on winter wheat yield in humid cropyear
162-167Views:77The effects of crop rotation, nutrien supply and crop protection technologies, as well as the appearance of the main ear- and leafdiseases
(powdery mildew, helminthosporium leaf spot, leaf rust, fusarium) were studied on the crop yields of winter wheat variety MV
Pálma during the 2009/2010 crop year. The experiments were conducted in triculture (pea – wheat – corn) and biculture (wheat – corn), at
five nutrition levels, with the use of three crop protection technologies (extensive, conventional and intensive) at the Látókép Research Site of
the University of Debrecen, Centre of Agricultural Sciences. Our results proved that the appearance of leaf- and ear-diseases were
significant in the wheat cultures during the 2009/2010 crop year, because of the rainy, warmer than usual weather, the lodging, and the huge
vegetative mass developed. The most severe infections by the four examined diseases after pea and corn pre-crops were observed at
extensive crop protection levels, when fertilizers were used at the highest dose.
Following corn pre-crop, in the case of all the three crop protection technologies the maximum rate of wheat yield results were achieved
at N150+PK level. The highest yield was reached at intensive crop protection level (6079 kg ha-1). In triculture, in case of all the three crop
protection technologies the maximum yields were achieved at N50+PK level; in extensive technology 5041 kg·ha-1 yield, in conventional
technology 6190 kg ha-1 yield was realised, while in the intensive technological model the yield was 7228 kg ha-1.
The relationship between yield and fertilizer amounts, the rate of pathogen contaminations, crop protection technologies and pre-crops
was defined with correlation analysis in case of different crop rotations during the 2009/2010 crop year. Based on the results of the
experiment, we found that in stands after corn pre-crop strong positive correlation was established between the crop protection level and the
crop yield (0.543), the nutrient levels and the emergence of the four examined pathogens, and between the nutrient levels and the yield
(0.639). Extremly strong positive correlation was observed between crop protection and yield (0.843) in triculture. Strong positive
correlation was detected between the nutrient levels and the presence of the four examined pathogens, as well as between nutrient and
lodging (0.688). Strong negative correlation was between the crop protection level and the four examined diseases both in biculture and
triculture.