The most dangerous pathogen for the European and American chestnuts is the blight fungus Cryphonectria parasitica (Murrill) Barr. Short after its introduction a big number of chestnut trees were destroyed on the infested area. The control could be really complicated, because of the numerous vegetative compatibility groups of the fungus. There i...s a type that carries a mycovirus viz. hypovirus in the cytoplasm. We are able to control effectively this pathogen by using mycovirus-carrying strains (called hypovirulent fungal strains also). In laboratory it is easy to multiply the virulent and the hypovirulent strains of the fungus but do not easy to differentiate colonies visually on simple PDA medium. During our research, we tested different types of media, based on potato and chestnut bark extract respectively. It was observed that on potato medium the virulent strains produce more orange pigments. So it is more easy to differentiate virulent or hypovirulent isolates of chestnut blight fungus based on colony colour and morphology.
Our botanical survey at the great pasture of Hajdúbagos is a part of a broad research that aims to predict the production of the grass at the given area. As the mentioned pasture is a nature conservation area, the usage of artificial fertilizers or other classic grassland management methods in its handling are prohibited. Thus grazing is an im...portant tool for the management of this area, however the not suitably regulated grazing order and the poorly calculated carrying capacity cause serious problems at some parts of the pasture. The prediction of the grass yield is essential to
avoid both over- and both under-grazing and for determining the optimal number of the grazing animal stock and the grazing method, thus the most suitable management strategy.
The potential grass yield is easily calculable with a computer model that will be established as a basis for determining the grass production. For the sake of getting an accurate view of the plant associations of the pasture, we created examination quadrates and determined all plant species found in the quadrates. After plant determination, we compiled a coenological table in which we marked besides the scientific name and families, the life forms of each species that refer to the structure, morphology and thus the adaptability of plants to their environment. We determined the
TWR, so the thermoclimate, water and soil reaction values, the nature conservation values, as well as the covering values of each plant species (DB), and the total coverage of the examination quadrates (B%).
According to the covering values, grasses proved to be characteristic plants at the examined pasture, thus we need to consider them influential in calculating the animal carrying capacity and with the rest of the information, we need to supply the model.
The life forms and TWR indicators, all together with the nature conservation values provide further important data to the development of the management suggestion of the protected pasture. By examining these values to different parts of the area, we could get an exact view on the measure of the degradation effects. This promotes the determination of grazing methods and the forming of the boundaries of certain pasture sections, to avoid those harmful anthropogenic effects that seriously endanger this extensive sandy pasture.
Chryphonectria 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 spec...ies (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.
Laboratory methods of semen evaluation are used to select males for artificial insemination. The current review describes several techniques that have been recently used for sperm analysis. Conventional microscopic methods in combination with the objective computerassisted sperm motility and morphology analyzers and flow cytometry, allows to ob...tain more precise information about the membrane and functional status of spermatozoa. By using several methods to detect motility, viability, acrosomal and capacitation status besides DNA integrity sperm biology and some of the mechanism involved in sperm cry injury can be better understood. The number of possible targets related to sperm quality is increasing, and possible that some of them could enable sperm analysis for predicting freezability and fertility to be improved.
Mg-treatment increased solid soluble content in roots probably due to the larger assimilation area.
The applied foliage fertilization affected inner colour intensity and uniformity in roots positively.
The 2% Mg-sulphate solution affected pigment quantity favourably depending on varieties.
Close correlation (r=0,71) was found between t
The Mg-sulphate foliage fertilization improves quality considerably but the individual reaction of varieties needs further studies.
Grapevine Trunk Diseases (GTD) is one of the most important diseases in vineyards worldwide, which can be found in Hungarian vineyards as well. In Hungarian wine regions there is very little information about the occurrence of pathogens which cause GTD, in case of Tokaj wine region there is no knowledge about that, what kind of pathogens can be... found in the vineyards.
The objective of our research is to assess the situation and occurrence of GTD in Tokaj wine region in cooperation with local specialists, as well as identification of pathogens which were isolated from the diseased trunks by morphological and genetic basis.
We were able to isolate endophytic fungi from all sampled grape trunk. The majority of them were determined as Diplodia seriata not only based on colony morphology, but also determined by rDNA sequences.
Morphological diversity of melon (Cucumis melo); phenotype reconstruction of a medieval sample. Morphological diversity among 47 melon (Cucumis melo) cultivars and landraces from Hungarian germplasm collection (ABI, Tápiószele) were analyzed with an ultimate aim to characterize morphologically cv. Hógolyó, which showed the closest genetic s...imilarity to a medieval melon recovered from the 15th century. Cultivars based on fruit morphology were grouped into the three main types of melon as reticulatus, cantalupensis and inodorus. Cluster analysis (by SPSS-11) based on 23 morphological (quantitative and qualitative) traits recorded revealed an extreme diversity among accessions, nevertheless cultivars were clustered into main melon clusters with only two exceptions of inodorus type cv. Zimovka J. and Afghanistan. Cultivars Sweet ananas and Ezüst ananász; and two Hungarian landraces Kisteleki and Nagycserkeszi showed close similarity. Cultivars Hógolyó and Túrkeve of inodorus type
were also grouped in one cluster, which provide insight into the morphological reconstruction of the medieval melon recovered from the 15th century. These results also indicate that old Hungarian landraces could be re-introduced into breeding programs for broadening genetic base of melon.
The cosmopolitan Phoma genus contains mainly phytopathogenic, opportunistic parasites, and saprophyte fungal species. Up to now, the characterization of Phoma species and other taxa of Phoma has been determined on the basis of morphology on standardized media, and gene sequence analysis was only used as a confirmative or distinctive complement....
In this study, we tried to find molecular markers which can be used as phylogenetics markers in the molecular based classification in the Phoma genus.
We employed a part of the translation elongation factor 1 subunit alpha (EF-1α=tef1) containing both introns and exons and ITS region containing the internal transcribed spacer regions 1 and 2 and the 5.8S rDNA, as potential genetic markers to infer phylogenetic relationships among different Phoma taxa. Twelve different Phoma species sequences were analysed together with the closely related Ascochyta ones. The constructed phylogenetic trees, based on tef1 and ITS sequences, do not support the traditional Phoma sections based on morphological characterization. However, we managed to distinguish between the Phoma strains and Ascochyta species by comparing their tef1 sequences through parsimony analysis. We proved that a tef1 can be a useful phylogenetic marker to resolve phylogenetic relationships at species level in Phoma genus.
Both parsimony sequence analyses confirmed that the Phyllosticta sojicola species is identical to the Phoma exigua var. exigua species as Kövics et al. (1999) claimed. However, the evolutionary distance by ITS sequences within Phoma species is too small to get well based consequences for the phylogenetic relationships of Phoma genus.
Further investigations would be necessary to clarify whether the tef1 and ITS sequences as phylogenetic molecular markers are well suited for the classification of Phoma species.
The European stone fruit yellows (ESFY) phytoplasma disease caused by pathogen ’Ca. Phytoplasma prunorum’ induces serious damages in cherry, sour cherry, peach, and apricot orchards mostly in Europe. Its known vector is the plum psyllid (Cacopsylla pruni). Many articles report on the biology (morphology, taxonomy, life cycle etc.) and the m...ethod of transmission of the pathogen by the vector, and the possibilities of their control. This paper reviews our knowledge about the vector, and summarises the results of an inland research carried out in a northeastern Hungarian apricot orchards. Our goal was to show some important data for the farmers or anyone who is interested in this disease and its vector. And give some known method that we can protect our orchards against them to prevent the appearance of the disease. As the psyllid that became infected with the pathogen can hold its infectionous capacity during their lifetime, it is very important to have enough knowledge about their lifecycle, that we can determine the right time and method to control them. We also have to know how to identify them; therefore, this paper lists several important data which can be helpful. The most important keys of identification are their wing color, which dark borwn in the apex and brown is in the remaining part of the forewing. The length of the antennae is also an important factor, since other genuse’s species have longer antennae than twice the width of the head. C. pruni has as long antennae as twice the width of the head. They return to Prunus species in early spring and we have to protect our orhards in this period against them. We have to use preparations with a knock down effect on them to prevent the inoculation of the pathogen into the trees in our orchards.
The cosmopolitan Phoma genus contains mainly phytopathogenic, opportunistic parasite, and saprophyte fungal species. Up to now the characterization of Phoma species and other taxa of Phoma has so far been determined on the basis of morphology on standardized media, and gene sequence analysis was only used as a confirmative or distinctive comple...ment.
In this study we have tried to study phylogenetic relationships by maximum likelihood method in the Phoma genus. We employed a part of the gene responsible for the synthesis of translation elongation factor 1 subunit alpha protein (tef1) containing both introns and exons, a part of the gene responsible for synthesis of tubulin protein and ITS region containing the internal transcribed spacer regions 1 and 2 and the 5.8S rDNA as potential genetic markers to infer phylogenetic relationships among different Phoma taxa. Twenty-four isolates of eleven different Phoma species were firstly characterised by morphologically, and then their tef1, tubulin and ITS sequences were sequenced and analysed by maximum likelihood method carried out by PAUP*4.0b program. According to constructed phylogenetic trees, the different Phoma taxons are well separated. However these trees do not support the traditional Phoma sections based on morphological characterization.
The maximum likelihood analyses of all three sequences confirmed that the Phyllosticta sojicola species is clustered with the Phoma exigua var. exigua group and the Phoma sojicola is grouped with Phoma pinodella group. The experienced molecular evidences initiate the demand of reclassification of formerly mentioned soybean pathogens.
Maize (Zea mays L.) is the most important consuming cereal crop in the world after rice and wheat. This requires an understanding of various management practices as well as conditions that affect maize crop performance. Water deficit stress during crop production is one of the most serious threats to crop production in most parts of the world a...nd drought stress or water deficit is an inevitable and recurring feature of global agriculture and it is against this background that field study of crops response to water deficit is very important to crop producer and researchers to maximize yield and improve crop production in this era of unpredicted climatic changes the world over.
A pot experiment was carried out to determine the effects of water deficit on growth and yield formation of maize. Two maize cultivars were used Xundan20 and Zhongdan5485. Three levels of soil water content were used in two stages of water control levels at two stages of the maize plant development
1. The JOINTING STAGE: A. CONTROL (CK) soil water content: from 70% to 80% of soil water holding capacity at the field, soil water content: from 55% to 65% of soil water holding capacity at the field, soil water content: from 40% to 50% of the Soil water holding capacity at the field.
2. The BIG FLARE PERIOD: A. CONTROL (CK) soil water content: from 75% to 85% of soil water holding capacity at the field, soil water content: from 58% to 68% of soil water holding capacity at the field, soil water content: from 45% to 55% of the soil water holding capacity at the field.
This research mainly studied the effects of water deficit on physiological, morphology and the agronomical characteristics of the maize plant at the different water stress levels.
The importance of these results in this experiment will enable plant producers to focus and have a fair idea as to which stage of the maize plant’s development that much attention must be given to in terms of water supply.