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The ascomycete fungus Venturia inaequalis causes scab disease, a major problem in apple production. The utilization of resistant cultivars is hindered by emerging new pathogen races, which erode their resistance. Increasing our knowledge on the population genetic processes of the fungus can contribute to the development of resistance gene deployment strategies and more durable resistance. We investigated the effect of four scab race indicator cultivars, ‘Gala’ (no R-gene), ‘Golden Delicious’ (Rvi1), ‘Geneva’ (Rvi3, complex), and OR45t132 (Rvi5), on the V. inaequalis population genetic structure and diversity. Sixty-six monosporic fungal isolates from the four cultivars were genotyped with seven simple sequence repeat primers. Furthermore, the partial resistance of the indicators and the pathogenicity profile of the conidia from each host were assessed. The genetic diversity and structure of the investigated V. inaequalis subpopulations correspond to the partial resistance of the original hosts as well as the subpopulations’ pathogenicity profiles. Indicators carrying Rvi3 and Rvi5 had strongly diverged and specialized V. inaequalis populations on them and fewer symptoms on the field. In line with the complete breakdown of the Rvi1 gene, the population from ‘Golden Delicious’ did not segregate from the susceptible ‘Gala’, and virulence towards Rvi1 was present in all subpopulations.

The European temperate forest zone has great importance, in terms of maintaining the habitats of not only forests but also anthropogenous grasslands, which were formed as a result of habitat reconstruction. These habitats have great importance, by means of nature conservation, landscape use, economy, and forest and grassland use. The mosaic-like habitat complexes that consist of these grasslands and forest patches help to increase biodiversity and supply the habitat for forest game. In this survey, changes in the vegetation of the temperate forests (Fagetum) of the Mátra Mountains of Hungary were investigated after reconstruction. In 2012, shrub cutting was carried out in the area of Parádóhuta, and then three different management methods (abandoning, mowing, and grazing) were utilized. Our goals were the following: to perform a vegetation survey of the sample areas (i); surveying the natural regeneration of the grassland and analyzing its biodiversity, nature conservation, and economical value (ii); and analyzing the vegetation in terms of nature conservation and valuing its life form spectrum, economy values, and livestock-feeding ability (iii). According to our results, systematic mowing and a less-intensive grazing had a significantly positive effect on biodiversity and the coverage of species, thus increasing the naturalness of the studied grassland habitats, while wild game were able to act as ecological engineers.

The thousands of kilometers of forest steppes in Eurasia belong to the most threatened ecosystems thanks to habitat loss. We have limited knowledge on the recolonization ability of forest steppe species to date, which is the reason we examined the textural and structural changes in these species during secondary succession in areas of different former land use. The species number, cover, and diversity of forest steppe species, especially those of the Festuco-Brometea group, became significant for all three types in the oldest fallows. The number and proportion of forest steppe species have been steadily increasing in abandoned vineyards and arable land, indicating that forest steppe species are able to rapidly recolonize. The increase in the number and cover of forest steppe species in abandoned grasslands reveals that the replacement of the species pool of these grasslands is not necessarily accompanied by degradation, but also by the appearance and spread of valuable natural species if the habitat is sufficiently patchy. The proportions of habitat categories level off in abandoned vineyards and arable land as abandonment progresses. The cover rates of disturbed habitats species were negligible for all three types for the third decade after abandonment, indicating a change in the quality of the species pool.

Loess vegetations of the Carpathian Basin have been ploughed for a thousand years. Therefore, loess steppes of verges of the Transdanubia have nearly disappeared. Therefore, in Hungary, it is also important to find out the composition of loess vegetation. The aims of our study were to date the age of the sample verges and explore types of verges. Is there a correlation between the types, location, expanse and vegetation types of the verges? Which of the coenologically important species of the genus Festuca occur in the verges and patches of loess grassland? The studies were carried out in three areas. We examined the age of the verges and their natural condition. Floristic and coenological surveys were applied to analyse the diversity of the verges. Inflorescence morphological analysis of the dominant Festuca species in the vegetation was carried out by analysing 25 parameters. Our results showed that not only the age of verges was valuable and natural. Most of the loess species did not appear in old verges. Consequently, we should not rely only on the age of the verges to make hypotheses about its natural condition and vegetation. Based on the coenological data, there were two types of verges, which were the interspaced verge and the border verge. Based on the diversity assessment from the survey, data of the interspaced verge showed the highest diversity value, the diversity value was higher than 4. Among the studied taxa, Festuca pseudovina was separated clearly as a homogeneous group. The morphotaxonomic parameters were not enough for species identification of F. valesiaca and F. callieri, but they were not enough for F. rupicola neither, so the examination of the sclerenchyma is required. Overall, in contrast to the previous hypothesis, the age of the grassland fragments is not the most important factor, but rather their location, size, the number of species and the diversity are adapted to them.