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Sensitivity of maize to herbicides in experiments in Martonvásár in 2015
47-52Views:158The phytotoxic effect of herbicides applied post-emergence was investigated in a herbicide sensitivity experiment set up on parental maize genotypes in Martonvásár. A total of 48 Martonvásár inbred lines and 12 single line crosses were included in small-plot experiments set up in two replications. Ten herbicides were applied at the normal authorised rate and at twice this quantity. Compounds intended for pre-emergence application were applied when maize was in the 3–4-leaf stage and post-emergence herbicides in the 7–8-leaf stage of development. The extent of phytotoxicity was scored two weeks after treatment. Some of the herbicides tested are not authorised for use in seed production fields, but it is important to know how the parental genotypes respond to all types of herbicides. Phytotoxic symptoms of varying intensity were only observed on a third of the 60 parental genotypes examined; the majority of the lines exhibited no reaction to any of the herbicides. Averaged over the 60 genotypes the level of phytotoxic damage was less than 10% for the single dose. When the double dose was applied somewhat more severe damage was induced by products containing Mesotrione + Nicosulfuron or Foramsulfuron + Isoxadifen-ethyl, but this was still below 15%. The herbicide dose had a three times stronger influence on the intensity of the symptoms than the type of herbicide. With the exception of Topramezone, there was a significant difference between the effects of the normal and double doses. The greatest dose effect differences, in decreasing order, were observed for Mesotrione + Nicosulfuron, Foramsulfuron + Isoxadifen-ethyl. Nicosulfuron and Mesotrione + Terbutylazine. The Mesotrione + Terbutylazine active ingredient combination only caused mild (<10%) symptoms on a total of 11 genotypes, while the Mesotrione + Nicosulfuron combination induced more severe phytotoxic symptoms on 26 lines. When Nicosulfuron was applied alone it caused milder symptoms on fewer genotypes than in combination with Mesotrione. Among compounds of the sulphonyl-urea type, the least severe symptoms on the fewest genotypes were recorded in the case of Prosulfuron.
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Phytotoxicity levels in a wet year in an experiment on maize sensitivity to herbicides
92-96Views:168The phytotoxic effects of herbicides applied pre-, early post- and post-emergence were studied in maize in a herbicide sensitivity experiment were set up in Martonvásár and Törökszentmiklós. The herbicides were applied in normal and in double doses to 37 Martonvásár inbred lines and to six parental single crosses. The small-plot experiments were set up in two replications. The wet weather that followed the pre- and early post-emergence treatments promoted the appearance of phytotoxic symptoms on maize. The degree of phytotoxicity was recorded on the 14th day after post-emergence treatment and on the 14th and 28th days after the pre- and early postemergence treatments. Herbicides applied pre-emergence only caused slight symptoms on maize. Although the double dose increased the damage, it was still not more than 5% on average. The symptoms caused by herbicides applied in the early post-emergence stage were more intensive than those detected in the pre-emergence treatments. However, the damage caused by the double dose of isoxaflutol + thiencarbazone-methyl and by the split treatment with nicosulfuron remained below 10%. The symptoms became somewhat more severe at the 2nd scoring date. Among the post-emergence treatments the maize genotypes had the least tolerance of the mesotrione + nicosulfuron combination of active ingredients, where the double quantities resulted in 13–14% damage in average.
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Changes in the herbicide tolerance of maize genotypes in wet and dry years
124-127Views:70The tolerance of 15 inbred maize lines grown on chernozem soil with forest residues in Martonvásár was tested against herbicides applied post-emergence in two dry, warm years (2003 and 2011) and in two cool, wet years (2004 and 2010). The herbicides mesotrione + terbutylazine, nicosulfuron and dicamba were applied to maize inbred lines in the 7–8-leaf stage at the maximum dose authorised for practical use and at double this rate. The plants were scored for the intensity of visible phytotoxic symptoms 14 days after treatment.
The level of phytotoxicity observed in dry, warm years was 5.14%, averaged over the lines, herbicides and rates. The intensity of visible symptoms was almost 2.5 times as great in cool, wet years (12.76 %).
Averaged over the four years, the lines and the rates, the least damage was caused by dicamba (5.77 %), followed by mesotrione + terbutylazine (7.23 %). The most severe symptoms were induced by nicosulfuron (16.17 %). This could be attributed to the fact that some of the inbred lines were extremely sensitive to herbicides, especially those of the sulfonylurea type.
A difference of more than 1.5 times was observed between the two doses, but the correlation between the concentration and the severity of the visual symptoms was not strictly linear. Compared to the normal dose (100 %) the double rate resulted in a 162.5% increase in symptom severity. In most cases plants treated with the normal dose were symptom-free or only exhibited a low level of phytotoxicity. -
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.
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An unimportant insect pest with characteristic symptoms: Halticus apterus (Miridae)
19-23Views:166Halticus apterus, a tiny mirid bug with jumping hind legs has not been taught in agricultural entomology courses in Hungary. However, the most detailed agricultural entomology text book, the “Handbook of Agricultural Entomology” briefly presents the pest. Although, it is common in Hungary, its damage is insignificant because of the low density; it can cause quality loss in feed crops only. Nevertheless, its special symptom – spottedness – is worth taking into consideration. The author has been studying pests and natural enemies of alfalfa for a long time (at least ten years), so he focused attention on this species. Occurrence of H. apterus was only sporadic in the alfalfa field, but it showed characteristic and frequent symptoms at a density of averagely three individuals per alfalfa plants in mixed plant associations at the studied field edge. By presenting the damage appearance and form, it was possible to make a more accurate description of H. apterus’symptoms, and with evaluating relevant European references, also the detailed entomological characterisation, economic importance and assessment of future risks have been achieved. As a difference to former descriptions, the special leaf spottedness of H. apterus does not consist of homogenous round spots but rather of spherical conglomerations of tiny whitish dots caused by the piercing and sucking mouthparts and the injected saliva
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Effect of M9, MM106 and Seedling Rootstocks on Sunburn-Sensitivity of 33 Apple Cultivars, and Sunburn Effects on Fruit Quality
236-247Views:77The purpose of this study was to investigate the sunburn-sensitivity of 33 apple cultivars grafted onto 3 rootstocks (M9, MM106 and seedling) in a commercial orchard at Nagykutas (in the western part of Hungary). The authors also searched for any relationship between fruit quality parameters and the frequency of sunburn on the fruit surface.
During the observations, the cultivars had rootstock-specific properties in respect to sunburn-susceptibility. Accordingly, the injury decreased in the order M9, MM106 and seedling rootstocks. The differences in the sensitivity were founded on the foliage-morphological characteristics of trees, caused by the growing vigour of the rootstocks. Accordingly, the highest value of sunburn injury was observed on M9 rootstock, because this rootstock has a dwarfing effect on the grafted main cultivars. Thus, the vegetative area of these trees grew very slowly and the foliage was not compact enough to protect the fruits from the strong rays. The largeness and density of the foliage increased in the order M9, MM106 and seedling rootstocks. Relationships were also demonstrated between the diameter of the upper part of crown, the size of leaves, the number of fruits per tree and the injury from sunburn.
The damage values showed, that the gravity of symptoms did not decrease below a well-defined level of dimension on fruit. Determined potential area of injury was necessary for the symptoms to become visible.
The authors categorized the cultivars in the respect of values of sunburn frequency: I. „Not sensitive”, II. „Moderately sensitive” and III. „Very sensitive” categories were constituted. Generally, the Gala cultivars showed low damage (or were free of symptoms), in contrast, Golden mutants suffered relative strongly. The most sensitive cultivar was Jonica on all three of rootstocks.
We searched for any relationship between the fruit quality parameters and the frequency of sunburn. A significant correlation was found in the cases of fruit weight and colour-coverage. The latter can be related to that fact that highly colour covered fruits are found on the peripherial part of crown, so these are exposed to stronger sun rays -
The role of non-optimum Fe-Zn ratio in the development of latent zinc shortage in cucumber (Cucumis sativus L.)
7-11Views:126The general micronutrient deficiency of the soils influences the quality of food production which causes human health problems in several countries as well. The non optimal Fe-Zn ratio can cause latent zinc deficiency – which the plants response in the function of their sensitivity –what has no visual symptoms or the plant shows deficiency symptoms in case of appropriate zinc supply. This phenomenon can cause significant decrease in the crop yield.
The aim of this study was to prove the role of non optimal Fe-Zn ratio in the evalution of latent zinc deficiency.
The non optimal Fe-Zn ratio caused decrease in the number of the leaves, the number and length of the internodes, the relative chlorophyll contents and in the dry matter production. According to the results the non optimal Fe-Zn ratio caused difficulties in the metabolism, which decreased the examined plant physiological parameters in the most cases. It can be concluded if there are higher iron contents in the tissues than zinc it can result latent zinc deficiency.
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Utility of Winter Wheat According to Visual and Microbiological Fusarium Infection, as Well as Toxin Examination
26-34Views:90In 1998 the Fusarium infection was studied visually and microbiologically and also F-2, T-2, HT-2, DAS and DON contamination were measured using 22 winter wheat samples. The correlation between the different parameters of 22 wheat samples were determined by regression analysis. According to our results we can state the following.
There is no significant connection between the results of visual, microbiological and toxicological examinations. This means that no certain conclusion can be drawn about the toxin contamination of samples – which is a determining factor of its utility – based on the visual symptoms and the plate dilution method.
Our results indicate however – though it is not proven statistically – that those samples in which the Fusarium infection did not exceed the limit of the standard, also had low toxin contamination, therefore they can be used as components of forage.
It is a considerable problem, however, that according to the visual qualification, such samples are excluded from the later utilisation, wherein the toxin contamination does not justify such action. Therefore, it is necessary to examine the toxin content of those samples which show high infection by visual symptoms. To reducing the number of expensive toxin examinations it would be advisable to change the currently used 0,5% limit which is indicated in the standard for a higher value of infection, for example to 2%, as recommended by Mesterházy (1998). -
Yearly change of Wheat dwarf virus infection rate during 1996-2010 in winter barley
22-28Views:96Yearly change of the infection of Wheat dwarf virus was studied in winter barley during 1996-2010. Surveys were carried out at Kompolt (Rudolf Fleischmann Research Institute, Róbert Károly College), in winter barley breeding lines showing leaf yellowing and stunting symptoms. In 1996, 250 winter barley samples were tested. During the period of 1997–2005, 100 samples were collected in each year. In 2006, 490 winter barley samples were tested. In 2007 and 2008 the number of samples collected was 500 from winter barley. In 2009 year 100, and in 2010 year 100 winter barley samples were collected for virus testing. Virus diagnosis was carried out using DASELISA for the detection of Wheat dwarf virus (WDV), Barley yellow dwarf viruses (BYDV-MAV, BYDV-PAV, BYDV-RMV, BYDV-SGV), and Cereal yellow dwarf virus (CYDV-RPV). During the ten of the last fifteen years, the occurrence of Wheat dwarf virus in infected samples exceeded those of other viruses causing leaf yellowing and dwarfing symptoms. There were years (1997, 2002, 2004, 2007, 2009 and 2010) when only the Wheat dwarf virus played the main role in development of yirus symtoms. A contrasting tendency can be observed between the degrees of infection of WDV and BYDV. With a rise of infection in the WDV, the proportion of BYDV decreased and vice-versa.
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Herbicide tolerance of maize genotypes in the wet 2016 year
13-18Views:145The herbicide tolerance levels of 49 Martonvásár inbred parents were examined in Martonvásár in a herbicide susceptibility trial in 2016. The normal dosage recommended in the permit documentations and double dosage were used for the 12 small-plot herbicide treatments performed in two repetitions. Spraying of early post-emergent herbicides was carried out in the 1–2-leaf stage, while post-emergent treatments were applied in the 7–8-leaf stage of maize. The extent of phytotoxicity was scored for the early post-emergent herbicides two and four weeks after treatments and for the post-emergent herbicides two weeks after treatments, respectively. Some of the herbicides examined are not approved in seed production; however it is important to know the reaction of maize parent genotypes for every type of herbicides. The active agent topramezone was withdrawn from the market in 2015, but it was included in the trials as its usage was allowed until stocks run out in 2016. The herbicide agents were examined as follows: mesotrione + S-metolachlor + terbutylazine; isoxaflutol + tiencarbazon methyl + cyprosulfamide; isoxaflutol + cyprosulfamide; mesotrione + terbuthylazine; tembotrione + isoxidifen-ethyl; mesotrione + nicosulfuron; prosulfu ron; nicosulfuron +prosulfuron + dicamba; bentazone + dicamba; nicosulfuron; topramezone; foramsulfuron + isoxadifen-ethyl.
Among early post-emergent herbicides, isoxaflutol + cyprosulfamide caused the less phytotoxic damage in the genotypes. The large amount of precipitation during the spring facilitated the infiltration of the active ingredient S-metolachlor, used regularly and successfully also in seed production, into the root zone, resulting in phytotoxic symptoms on susceptible inbred lines at the time of the first inspection. These genotypes recovered by the end of the vegetation period. The spring weather was cooler than usual, retarding the development of maize and thus led to the slower fermentation of herbicide active ingredients, accordingly, all of the post-emergent herbicides caused visible phytotoxic symptoms on some of genotypes. The most severe damages were generally caused by the double dosage of nicosulfuron + prosulfuron + dicamba, nicosulfuron, and foramsulfuron + isoxadifen-ethyl. -
A morphological survey of Ustilago trichophora, a smut fungi and evaluation as bioherbicidal agent for barnyard grass (Echinochloa crus-galli)
91-93Views:143Ustilago trichophora (Link) Kunze is a widespread smut fungus in all over the world. This fungus is pathogenic on species of Echinochloa genus. The subject of present research was that smut fungi occurrence on barnyard grass (Echinochloa crus-galli). Numerous barnyard grass plants with symptoms of smut galls caused by Ustilago trichophora on stems were collected from two counties, víz. Hajdú-Bihar (East-Hungary) and Jász-Nagykun-Szolnok (Middle-Hungary). The infested plants were examined in laboratory, which included the observation of the symptoms and the morphological properties of the spores and the colonies developed from sporidia. The results suggested that this fungus could be effective against barnyard grass weed so the biological control of this weed plant (Echinochloa cruss-galli) can be managed by using Ustilago trichophora biopreparates. As Ustilago trichophora can produce abundant sporidia in liquid culture, a high effectiveness control should be apply by Ustilago trichophora smut fungus as a mycoherbicide in Echinochloa weed control.
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An unusual occurrence of Taphrina deformans on apricot trees in Hungary
86-92Views:113In 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.
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The effect of sunburn damage on the fruit quality parameters of apple (Malus domestica cv. Idared)
55-64Views:97In the present study the authors investigated the effect of sunburn injury on fruit quality parameters (cover colour, depth of tissue damage, fruit flesh firmness, dry matter content) of apple.
The symptoms of sunburn injury appeared as concentric rings, differing in colour from each other and the cover colour. This can be connected with the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of spots on the surface of the fruit) dark brown (strongly damaged), light brown (moderately damaged), pale red transition (weakly damaged), red surface cover colour (not damaged).
Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low relative humidity. In the initial phase, a light corky layer, golden or bronze discolouration and injuries of the epidermal tissue appear on the surface exposed to radiation. Thus, it detracts from the fruit’s appearance, but in most of the cases it would not cause serious damages in the epidermal tissue. The depth of tissue damage is not considerable, its values are between 1.5-2.0 mm in general. It is commonly known, that tissue structure of the apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
On the basis of the flesh firmness studies, it can be stated that the flesh firmness of the damaged parts increases due to the sunburn effect. This is due to the fact that the damaged plant cells die, the water content of the tissue decreases and it hardens. However, due to this reduction in the water content the dry matter content will increase. -
Field Tests on the Herbicide Tolerance of Various Maize Genotypes
21-23Views:68Investigations were made in Martonvásár on the herbicide tolerance of 22 inbred maize lines and 3 parental single crosses when treated with one herbicide applied after sowing, prior to emergence, and with seven applied post-emergence in the 6-8-leaf stage. Visible damage was scored 14 days after the treatment.
An analysis of the phytotoxic effects led to the conclusion that a single dose of the tested herbicides did not cause any damage to the genotypes investigated, with the exception of one inbred line, which was extremely sensitive to herbicides of the sulphonyl carbamide type and moderately sensitive to both rates of dicamba. In many cases, a double dose of the herbicides caused mild or moderate symptoms on the maize lines. -
Studies of Cryphonectria parasitica (MURR.) BARR subpopulations on Quercus petraea in Ukraine
70-75Views:95Chryphonectria parasitica (Murr.) Barr, the casual agent of chestnut blight disease, which is one of the most important fungal pathogens of chestnut (Castanea sativa). The disease seriously affected the chestnut in Northern-America and in Europe as well. It is important to mention that the pathogen does not only infect the chestnut but oak species (Quercus spp.) also. In the Carpathian-Basin, the chestnut is endemic in the Mecsek mountains, in Zala, in Somogy counties but it also can be found in the Danube-Bend. In the Carpathian-Basin (outside Hungary) the chestnut is found in Slovakia, Ukraine, Romania. In our study bark samples infected by Cryphonectria parasitica were collected from Bobovyshche, Serednje and Rostovjatica (Ukraine). The rate of infected chestnut tree were higher than 90% around Bobovyshche and beside chestnut, the symptoms were detected on oak trees as well. We collected bark samples from chestnut and oak as well and then we isolated the pathogen Cryphonectria parasitica in the lab of University of Debrecen. Symptomatological observations, laboratory examinations on fungus morphology, as well as comparisons of ITS sequency homology were made and approved that the causal agent of new disease was Cryphonectria parasitica. Our results proved that the Cryphonectria. parasitica infects oak trees beside chestnut in the Carpathian-Basin. Further studies are needed to determine the VCG (Vegatative Compatibility Group) group of the Cryphonectria parasitica found on oak trees.
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Heat stress of cattle from embryonic phase until culling
11-22Views:246Heat stress becomes a serious problem in the livestock sector as it affects cows' performance negatively. The objective of this paper review is to investigate the effects of heat stress during the different phases of the life cycle of cows; embryos, calves, heifers, and cows. Heat stress during early maternal gestation affects the ability of embryos to develop increasing the risk of abortion and early embryonic death. Heat stress during late maternal gestation affects the performance of calves and heifers later in their life, as it reduces growth performance, conducts physiological changes, impaired immunity, changes the behavior, and reduces the length and intensity of the estrus in heifers with decreasing in milk production in the first lactation. On the level of cows, milk quality and production, meat quality, and the final body weight decrease under hot temperatures. Heat stress decreases the conception rate, alters follicle growth, and estrous symptoms. Hormones secretion and physiological changes because of the heat stress conduct to impair the immunity system, and in oxidative stress and death in some cases. Same as for calves and heifers a change in the behavior of cows was detected in order to decrease their temperature.
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Preliminary estimation of the efficacy of Fusarium sporotrichioides Sherb. as biological control agent against common milkweed (Asclepias syriaca L.)
201-204Views:248A study of fungi responsible for severe leaf spots of common milkweed (Asclepias syriaca L.) in the Hajdúság region (East Hungary), Fusarium sporotrichioides and Alternaria alternata were isolated from infested leaf tissues. F. sporotrichioides was the most virulent fungus in pathogenicity tests conducted on healthy leaves of common milkweed plants. Inoculation of common milkweed (A. syriaca) in different growth stages with F. sporotrichioides yielded similar symptoms as the original ones. Spray mixtures containing 1.0×106 conidia/ml gave effective control when common milkweed plants were sprayed until runoff occurred. Laboratory (wet chamber) and field experiments showed that asexual spores of the fungal pathogen, F. sporotrichioides, exhibited bioherbicidal activity against common milkweed (A. syriaca).
More efficient control efficacy was observable on elder plants (at flowering stage) than younger ones. These results initiate that this fungus may be a biocontrol agent for controlling this invasive weed but should clarify its hosts because it could infect cultivated plants as well.
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The Effect of Sunburn on Fruit Quality of cv. Idared Apple
23-31Views:78The aim of this study is to investigate the effect of sunburn injury on fruit quality parameters (colour-coverage, depth of affected tissue, fruit flesh firmness, soluble solids content) of apple.
The symptoms of sunburn injury appeared in concentric ring shape, differed from each other and surface colour-coverage. This can be due to the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of the blotch on the transversal diameter of the fruit) dark brown (strongly affected), light brown (moderately affected), pale red transition (poorly affected), red surface colour-coverage (not affected).
Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low air relative humidity that in the initial phase results in a light corky layer, golden or bronze discolouration, and injuries to the epidermal tissue, in the surface exposed to radiation. Thus it detracts from its appearance, but in most cases, it would not cause serious damage to the epidermal tissue. The depth of affected tissue is not considerable, its values are between 1.5-2.0 mm generally. It is commonly known that the tissue structure of apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
On the basis of flesh firmness research, the authors established that the measure of flesh firmness of the affected part of apple fruit increases with the effect of sunburn. The consequence of this is the suffered plant cells will die, the water content of this tissue decreases and the fruit gets harder. This water-loss caused the increase of soluble solids content. -
The role of some elicitors in inducing chilling stress resistance in apricot fruit
27-32Views:139This study aimed to study the role of 2 mM salicylic acid and 0.2 mM methyl Jasmonic acid in reducing the chilling injuries on two different apricot varieties fruits (Bergarauge and Flavor cot). These treatments were applied for apricot fruit directly after harvest after measuring the zero time data. Then the fruit were stored at 1 oC for three weeks and were examined 7 day periodically, other group of fruit was stored at 1 oC for 15 days then transport to room temperature and examined after 4 and 8 days. The fruit samples were collected at each examination time, and the measurements containing the fruit firmness (Kg cm-2), chilling and decay index, membrane electrolyte leakage, total phenol content and phenylalanine ammonia lyase mechanism (PAL) activity. The results showed that there are no obvious differences between the tested varieties and the differences may back to genetic variations and they took the same trend for most of measurement after treated with SA and MJ. SA and/or MJ treated fruit achieved low percentage of fruit softening in comparison to water treated fruit. At the same time the chilling and decay index showed that the SA and/or MJ reduced the decay or breakdown symptoms in either tested varieties. The treated fruit with those elicitor help the fruit to keep about stable phenol content while water treated fruit lose the phenol content sharply at early storage and this stable level of phenol my because of the ability of those chemical to raise PAL activity in treated fruit.
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Fruit melanotic ringspot (FMRS) – a disease of resistant Capsicum genotypes infected with Tomato spotted wilt virus (TSWV) on the fruits
64-69Views:64Etiology of pepper fruit melanotic ringspot (FMRS) disease (Salamon, 2009) was studied on fruit samples collected in forced pepper populations. It was noticed that in spite of heavy thrips (Frankliniella occidentalis) infestations and of TSWV epidemy detected in the forcing houses, FMRS occurred only in plants having healthy foliage. Symptomatological surveys strongly suggested that FMRS appeared exclusively in specific pepper genotypes. The size of melanotic ringspots has been observed to grow at room temperature during postripening of diseased fruits. A mechanically transmitted plant virus was isolated from symptomatic parts of 9 white pepper fruits affected by FMRS. On test plants each of the virus isolates caused systemic symptoms characteristic to TSWV. Using cDNA/PCR technique and TSWV N-gene specific primers a ca. 300 bp long DNA fragment has been amplified from total nucleic acid extracted from symptomatic tissues but never from asymptomatic parts of the fruits showing FMRS. Plant progenies grown from seeds of FMRS diseased fruits segregated in respect of resistance and/or susceptibility to TSWV infection. TSWV was also detected in and isolated from three fruits showed non-melanotic yellow rings (one of them was infected with a tobamovirus, too). Seedlings derived from these fruits proved to be susceptible to TSWV. Based on the above results we could conclude that the FMRS disease developed on fruits of “cecei” type white peppers that carry a TSWV resistance gene, most likely the Tsw gene in heterozygous form. These fruits were infected with thrips transmitted TSWV and FRMS appeared as a hypersentive reaction (HR) manifested in fruits.
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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.
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Fungi detected in trunk of stone fruits in the Czech Republic
121-127Views:206This study was focused on detection of the spectrum of fungi in the wood of stone fruits using molecular genetic methods. Samples were obtained from apricots, plums and sweet cherry trees from region of Moravia, one sample was obtained from Myjava (Slovakia). Segments of symptomatic wood were obtained from dying stone fruit trees with very significant symptoms. This study describes detection of the fungi in the wood of 11 trees in general in 5 localities. The cultivation of the fungi from symptomatic wood and sequencing of ITS was carried out. Eleven fungal genera were determined in the stone fruits wood, particularly Irpex lacteus, Fomes fomentarius, Neofabraea corticola, Calosphaeria pulchella, Cytospora leucostoma, Phellinus tuberculosus, Stereum hirsutum, Collophora sp., Pithomyces chartarum, Aureobasidium pullulans,Fusarium sp. The results of this study demonstrate that the reason of declining of stone fruit trees in Moravia is caused probably by trunk pathogens.
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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 Fattening and Slaughtering Examination at the Hungarian Racka Sheep
37-42Views:88Fattening and slaughtering characteristics of both types (black and white) of the Hungarian racka sheep were investigated at the site of the National Institute for Agricultural Quality Control in Atkár. The Hungarian merino, the dairy cigaja and the British milksheep were applied as control groups. 10 animals were examined from both sexes in each genotype. The examination was carried out according to the principles set in the Codex for sheep breeding. During the test acute diarrhoea occurred in each control group. However, only few lambs were excluded from the test from the British milksheep and the Hungarian merino groups because of significant changes in their condition. Consequently, the results obtained were not significantly influenced. No symptoms of any illness could be recognised in the Hungarian racka sheep, though. The significance of the difference between the average of the examined groups were checked by T-tests.
Daily gain was significantly less compared to the control groups, except for the white racka males. The lambs starving for 24 hours before slaughtering weighed 25.3-30.0 kgs on average. The black and white racka females weighed the least while the Hungarian merino females weighed the most. The quantity of abdominal and kidney fat was significant in the case of our native females. The quantity of abdominal fat was significantly bigger compared to each control group. On comparing the investigated groups it turned out that the white racka males had the biggest skin weight while the white Hungarian racka females had the smallest, that is the two extremes were recognised in the same colour (white) of one bred. On qualifying the slaughtered animals females had better results than males in each bred; the racka sheep were better than the dairy cigaja but were worse than the Hungarian merino and British sheep groups.
The huge differences in the carcasses of the groups were seen clearly when chopping. Examining the leg, it was noticed that the native groups proved to be smaller than the control groups, except for the black racka males. As for the short loin, the Hungarian racka and the Hungarian merino sheep proved to be the best, whereas the dairy cigaja and the British milk males had much smaller ones. The results gained when investigating the rack were similar to those of the short loin. As far as the rib and shoulder are concerned, the black racka females and the dairy cigaja females had the worst results. After chopping, the right side was also boned in every group. The small proportion of bone in the case of racka sheep was easily noticeable that resulted in the fact that the white racka females had the highest quantity of short loin compared to the other groups. When examining the back quarter, the bone proportions of the 4 racka groups proved to be significantly less than those of the control groups but it was not true for the meat proportions. As for the front quarter meat, the racka males were prominent in the great shoulder meat and in the small proportion of bone. The quantity of the first quarter bone was the least in the case of racka sheep and was the biggest for dairy cigajas. This difference proved to be significant in most cases.
In short, the Hungarian racka groups had the best results in meat quantity, which was especially significant compared to the dairy cigaja sheep. However, the quantity of external fat increased. -
Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
9-14Views:267Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.