This is a continuation of a series focused on providing a stable platform for the taxonomy of phytopathogenic fungi and fungus-like organisms. This paper focuses on one family: Erysiphaceae and 24 phytopathogenic genera: Armillaria, Barriopsis, Cercospora, Cladosporium, Clinoconidium, Colletotrichum, Cylindrocladiella, Dothidotthia,, Fomitopsis, Ganoderma, Golovinomyces, Heterobasidium, Meliola, Mucor, Neoerysiphe, Nothophoma, Phellinus, Phytophthora, Pseudoseptoria, Pythium, Rhizopus, Stemphylium, Thyrostroma and Wojnowiciella. Each genus is provided with a taxonomic background, distribution, hosts, disease symptoms, and updated backbone trees. Species confirmed with pathogenicity studies are denoted when data are available. Six of the genera are updated from previous entries as many new species have been described.

(I. Majláth). 2 SUMMARYThe rate of carbon and nitrogen assimilation is highly sensitive to stress factors, such as low temperature and drought. Little is known about the role of light in the simultaneous effect of cold and drought. The present study thus focused on the combined effect of mild water deficiency and different light intensities during the early cold hardening in durum wheat (Triticum turgidum ssp. durum L.) cultivars with different levels of cold sensitivity. The results showed that reduced illumination decreased the undesirable effects of photoinhibition in the case of net photosynthesis and nitrate reduction, which may help to sustain these processes at low temperature. Mild water deficiency also had a slight positive effect on the effective quantum efficiency of PSII and the nitrate reductase activity in the cold. Glutamine synthesis was affected by light rather than by water deprivation during cold stress. The invertase activity increased to a greater extent by water deprivation, but an increase in illumination also had a facilitating effect on this enzyme. This suggests that both moderate water deficiency and light have an influence on nitrogen metabolism and sucrose degradation during cold hardening. A possible rise in the soluble sugar content caused by the invertase may compensate for the decline in photosynthetic carbon assimilation indicated by the decrease in net photosynthesis. The changes in the osmotic potential can be also correlated to the enhanced level of invertase activity. Both of them were regulated by light at normal water supply, but not at water deprivation in the cold. However, changes in the metabolic enzyme activities and osmotic adjustment could not be directly contributed to the different levels of cold tolerance of the cultivars in the early acclimation period.

Developing ‘climate smart forestry’ (CSF) indicators in mountain forest regions requires collection and evaluation of local data and their attributes. Genetic resources are listed among the core indicators for ‘forest biological diversity’. This study is a report on the evaluation of the standing genetic diversity within and across 12 pure beech stands (<i>Fagus sylvatica</i> L.) established within the CLIMO project, using nuclear microsatellite markers. The sampling sites were set along the species’ distribution range, including the Balkan region and extending towards the Iberian Peninsula. Cores or leaves from 20-23, old, mature trees per plot were sampled for DNA analysis. Genetic diversity indices were high across the range (H_E = 0.74 - 0.81) with the highest in the Bosnian Mountains. Genetic divergence increased significantly with the geographical distance (Mantel test: r=0.81. p<0.001). Most of the stands exhibited an excess of heterozygotes, with the highest value at the Hungarian site (H_O/H_E = 1.177), where beech persists close to the eastern xeric limit of the species’ distribution. STRUCTURE revealed within–region differentiation in the Balkan Peninsula, where Bulgarian stand was the most outstanding. The genetic parameters of each stand could be assessed as a resource for CSF indicators interpreted especially at the local level.

Maize is sensitive to cold injury, especially during germination. Since cold causes oxidative stress, compounds that promote the accumulation of free radical forms, such as the reactive aldehyde (RA) methylglyoxal (MG), may be suitable to trigger a systemic defense response. In this study, maize seeds were soaked in MG solution for one night at room temperature, before germination test at 13°C. The exogenous MG enhanced the germination and photosynthetic performance of maize at low temperature. Transcriptome analysis, hormonal, and flavonoid profiling indicated MG‐induced changes in photosystem antenna proteins, pigments, late embryogenesis abundant proteins, abscisic acid (ABA) derivatives, chaperons, and certain dihydroflavonols, members of the phenylpropanoid pathway. MG‐response of the two maize cultivars (A654 and Cm174) were somewhat different, but we recorded higher endogenous hydrogen peroxide (H2O2) and lower nitric oxide (NO) level in at least one of the treated genotypes. These secondary signal molecules may provoke some of the changes in the hormonal, metabolic and gene expression profile. Decreased auxin transport, but increased ABA degradation and cytokinin and jasmonic acid (JA) synthesis, as well as an altered carbohydrate metabolism and transport (amylases, invertases, and SWEET transporters) could have promoted germination of MG‐pretreated seeds. While LEA accumulation could have protected against osmotic stress and catalase expression and production of many antioxidants, like para‐hydroxybenzoic acid (p‐HBA) and anthocyanins may have balanced the oxidative environment for maize germination. Our results showed that MG‐pretreatment could be an effective way to promote cold germination and its effect was more pronounced in the originally cold‐sensitive maize genotype.

Ecologically extreme habitats at a species’ distribution edges bear significance for biota under adverse climatic conditions and climate change. Range-edge populations adjust their functional traits to the special local ecological conditions, leading to increased intraspecific variability in their morpho-anatomical structure and, consequently, favor population survival in the absence of competitors. On the basis of wood anatomical traits, such as tracheid lumen area (CA), cell wall thickness (CWTrad), cell diameter-to-radial cell wall thickness ratio (CD/CWT), and the number of tracheids in the radial tracheid files (TNo), we investigated the xylem adjustment of Pinus sylvestris L. populations from six ecologically extreme habitats from the Eastern Carpathians and the Pannonian Basin. Results indicated significant differences among all studied sites in case of all wood anatomical traits as signs of the local adaptation of trees. Peat bog populations adapted their wood anatomical traits to the generally hydric, cool and anaerobic conditions of the peat bogs, exhibiting smaller CA and proportionally thick CWTrad to ensure the hydraulic safety of the stem, whereas, on the lowland site, trees were characterized by a more effective water-conducting system, developing larger CA with relatively thin CWTrad with lower carbon-per-conduit-costs at the expense of higher vulnerability to cavitation. Radial tree ring growth and TNo also differed markedly among sites, following the temperature and groundwater constraints of the habitats. Wood anatomical variability among tree rings and the corresponding short-term climate response of populations differed from the adaptive responses of the trees to the ecological characteristics of the habitat. In addition to the different phylogeographic origin evidenced in former studies, phenotypic differentiation by the habitat type of the studied populations linked to the variance in morpho-anatomical traits have contributed to the survival of the peripheral Scots pine populations at the species’ range margins.